JP7780949B2 - Laser marking device and laser marking system - Google Patents

Description

This disclosure relates to a laser marking device and a laser marking system.

Patent Document 1 discloses a laser marking device with an external monitor camera. Specifically, this laser marking device is equipped with a monitor camera for capturing an image of the workpiece, and a display means for displaying the monitor image obtained by the monitor camera. Here, the monitor camera is attached to the side of the scanning head, and can capture an image of the workpiece from diagonally above.

According to Patent Document 1, a certain working distance (hereinafter simply referred to as "WD") is maintained between the bottom surface of the scanning head and the top surface of the workpiece. This also makes it possible to position the monitor camera away from the workpiece, allowing a wide range to be captured within the imaging field of view.

JP 2016-034654 A

However, when the working distance cannot be secured as far as in the case disclosed in Patent Document 1, the gap between the underside of the scanning head and the workpiece becomes very small. In this case, using a conventional monitor camera would only be able to capture a narrow range within the imaging field of view, making it difficult to use.

The technology disclosed here was developed in light of these issues, and its purpose is to improve the usability of camera-equipped laser marking devices.

A first aspect of the present disclosure relates to a laser marking device that includes a laser light generation unit that generates laser light, a laser light scanning unit that reflects the laser light generated by the laser light generation unit and scans the laser light over the surface of a workpiece, and a housing that houses the laser light generation unit and the laser light scanning unit.

According to a first aspect of the present disclosure, the housing includes a storage section in which an optical element that transmits the laser light reflected by the laser light scanning section is provided, a pair of extension sections that extend from the storage section along the emission direction of the laser light so as to sandwich the optical axis of the laser light that has transmitted through the optical element, and a camera mounting section to which an imaging device can be mounted so that the imaging optical axis passes through the internal space formed by the pair of extension sections.

According to the first aspect, by laying out the imaging optical axis so that it passes through the space between the pair of extensions (the internal space), it is possible to extend the imaging optical axis from the imaging device to the work surface even when the distance between the housing and the work is very short. This makes it possible to fit a wider area into the imaging field of view, improving the usability of the laser marking device.

Furthermore, according to a second aspect of the present disclosure, the housing may have a bottom surface on which the optical member is provided and a top surface opposite the bottom surface, and the housing may be configured to be suspended via the top surface.

When the housing is suspended from above, as in the second aspect, the distance between the housing and the workpiece may be shorter than when it is supported from the side, below, etc. Even when adopting such a layout, the configuration disclosed herein can ensure a wider imaging field of view, which is advantageous in improving the usability of the laser marking device.

Furthermore, according to a third aspect of the present disclosure, at least one of the pair of extension portions may house a heat sink thermally coupled to the laser light generating portion.

According to the third aspect, the internal space of the pair of extensions can be used as a space to accommodate the heat sink. This makes it possible to effectively utilize the internal space of the pair of extensions without leaving it as dead space.

Furthermore, according to a fourth aspect of the present disclosure, the pair of extension portions may comprise a first extension portion disposed on one side in a first direction with respect to the optical axis of the laser light, and a second extension portion disposed on the other side in the first direction across the optical axis of the laser light and spaced apart from the first extension portion; the housing may have a wall portion connecting the first and second extension portions and dividing the internal space, and a mirror mounting portion disposed on the wall portion and configured to be able to mount a reflecting mirror; and the camera mounting portion may be configured to install the imaging device such that the imaging optical axis passes through an opening formed in a position facing the wall portion and intersects with the mirror surface of the reflecting mirror.

According to the fourth aspect, by configuring the wall portion to be able to have a reflective mirror attached, it is possible to bend the imaging optical axis using the reflective mirror. This makes it possible to adopt a wider variety of layouts when arranging the imaging optical axis so that it passes through the internal space. Increasing the degree of freedom in the layout of the imaging optical axis contributes to improving the usability of the laser marking device.

Furthermore, according to a fifth aspect of the present disclosure, the reflecting mirror may be attached to the mirror mounting portion, and the mirror surface of the reflecting mirror may be positioned so as to bend the imaging optical axis toward the surface of the workpiece.

According to the fifth aspect, a reflecting mirror attached to the wall can guide the imaging optical axis to the surface of the workpiece. This allows the laser light irradiation area set on the workpiece surface to coincide with or be close to the imaging field of view of the imaging device. This makes it possible to capture an image of the workpiece immediately after or immediately before marking, for example, which is advantageous in improving the usability of the laser marking device.

Furthermore, according to a sixth aspect of the present disclosure, the laser marking device may be provided with a lighting mounting portion disposed within the internal space and configured to allow lighting to be mounted thereto.

According to the sixth aspect, it is possible to lay out lighting within the interior space. This improves the quality of captured images, such as visibility, and is therefore advantageous in improving the usability of the laser marking device.

Furthermore, according to a seventh aspect of the present disclosure, the lighting may be attached to the lighting attachment portion, and the lighting may be positioned so as to be oriented in a direction intersecting the imaging optical axis.

According to the seventh aspect, the imaging optical axis and the direction in which the illumination light is emitted differ, making it possible to suppress halation and other problems caused by specular reflection of the illumination light. This improves the quality of the captured image and is advantageous in improving the usability of the laser marking device.

Furthermore, according to an eighth aspect of the present disclosure, the imaging device may be mounted within the housing, and the imaging device may be configured as a wide-angle camera having a wide-angle lens.

A ninth aspect of the present disclosure relates to a laser marking system including the laser marking device and a transport device that transports a workpiece along a predetermined transport direction, wherein a plurality of printable areas are set on the surface of the workpiece at equal intervals along the transport direction, and the laser marking device is configured to sequentially mark each printable area transported by the transport device.

According to a ninth aspect of the present disclosure, the laser marking system may include an approach monitoring unit that detects approach between the housing and one of the printing areas, the conveying device stops conveying upon receiving a detection signal from the approach monitoring unit, the laser marking device performs marking on the one of the printing areas while the conveying device has stopped conveying, and the imaging device performs imaging of the one of the printing areas on which marking has been performed by the laser marking device while conveying by the conveying device has stopped.
A laser marking system characterized by:

According to the ninth aspect, the quality of the captured image can be improved by configuring the system to capture images while transport is stopped. This is advantageous in improving the usability of the laser marking device.

Furthermore, according to a tenth aspect of the present disclosure, the laser marking system may include an inspection device that inspects the marking content made by the laser marking device based on the imaging results of the imaging device, and the inspection device may inspect the marking on the one printing area after the imaging device has imaged the one printing area and the conveying device has resumed conveying.

According to the tenth aspect, the inspection device inspects the markings while the workpiece is being transported. Whether or not to inspect the markings does not depend on whether or not the workpiece is being transported. This allows for more efficient inspection.

An eleventh aspect of the present disclosure relates to a laser marking system including the laser marking device and a transport device that transports a workpiece along a predetermined transport direction, wherein a plurality of printable areas are set on the surface of the workpiece at equal intervals along the transport direction, and the laser marking device is configured to sequentially mark each printable area transported by the transport device.

According to an eleventh aspect of the present disclosure, the laser marking system may include a proximity monitoring unit that detects the proximity of the housing to one of the printable areas, and the laser marking device may mark the one of the printable areas being transported by the transport device each time it receives a detection signal from the proximity sensor, and the imaging device may capture an image of the one of the printable areas within a period from when the laser marking device marks the one of the printable areas to when the proximity monitoring unit outputs a detection signal for another of the printable areas being transported following the one of the printable areas.

Furthermore, according to a twelfth aspect of the present disclosure, the imaging device may be configured as a line scan camera having an imaging field of view extending along a conveying width direction perpendicular to the conveying direction.

Furthermore, according to a thirteenth aspect of the present disclosure, the laser marking system may include an inspection device that inspects the marking content performed by the laser marking device based on the imaging results from the imaging device, and the inspection device may inspect the marking for one printable area within the period from when the laser marking device performs marking on one printable area to when the approach monitoring unit outputs a detection signal for the other printable area.

As described above, this disclosure can improve the usability of camera-equipped laser marking devices.

FIG. 1 is a diagram illustrating an example of the overall configuration of a laser marking system. FIG. 2 is a block diagram illustrating a schematic configuration of a laser marking device. FIG. 3 is a diagram for explaining the replacement of the printing device and the marker head. FIG. 4 is a perspective view illustrating an example of the appearance of the marker head. FIG. 5 is a view corresponding to FIG. 4 illustrating a state in which the cover member is removed from the marker head. FIG. 6 is a side view of the marker head. FIG. 7 is a perspective view illustrating a state in which the cover member is removed from the marker head. FIG. 8 is a perspective view illustrating an example of a housing structure for the marker head. FIG. 9 is a perspective view illustrating an example of a housing structure for the marker head. FIG. 10 is a cross-sectional view schematically illustrating the internal structure of the marker head. FIG. 11 is a diagram for explaining the positional relationship between the marker head and the workpiece. FIG. 12 is a perspective view for explaining the attachment of the marker head to the support member. FIG. 13 is a perspective view illustrating the configuration of the camera attachment portion and the camera unit. FIG. 14 is a diagram illustrating a schematic example of the relationship between the imaging optical axis and the internal space. FIG. 15 is a diagram illustrating a schematic example of the relationship between the irradiation area and the imaging area. FIG. 16 is a flowchart showing the control process carried out when operating the laser marking system, focusing on the processing related to the imaging device. FIG. 17 is a time chart illustrating the time series of still printing. FIG. 18 is a time chart illustrating the time series of moving and printing. FIG. 19 is a table illustrating the contents of the inspection log. FIG. 20 is a view corresponding to FIG. 11 and showing a first modified example of the laser marking device. FIG. 21 is a view corresponding to FIG. 11 and showing a second modified example of the laser marking device. FIG. 22 is a diagram showing a modified example of the camera unit.

Embodiments of the present disclosure will be described below with reference to the drawings. Please note that the following description is for illustrative purposes only.

In other words, although this specification describes a laser marker as an example of a laser processing device, the technology disclosed herein can be applied to laser-applied equipment in general, regardless of whether it is called a laser processing device or a laser marker.

In other words, in this embodiment, printing processing (hereinafter referred to as "marking", "printing", or simply "processing") will be described as a representative example of marking using laser light, but this disclosure can be applied to any marking consisting of multiple scanning lines, such as graphic marking.

<Overall structure>
Fig. 1 is a diagram illustrating the overall configuration of a laser marking system S, and Fig. 2 is a diagram illustrating the schematic configuration of a laser marking device L in the laser marking system S. Also, Fig. 3 is a diagram for explaining the replacement of a printing device 1001 with a marker head 1, Fig. 11 is a diagram for explaining the positional relationship between the marker head 1 and a workpiece W, and Fig. 12 is a perspective view for explaining the attachment of the marker head 1 to a support member 501.

The laser marking system S illustrated in Figure 1 includes a laser marking device L, an external device 400 connected to it, and processing equipment 500 to which the laser marking device L is attached and which transports a workpiece W. Of these, the laser marking device L illustrated in Figures 1 and 2 irradiates a laser beam toward a predetermined irradiation area R1 and scans the laser beam over the surface of the workpiece W.

By scanning the laser light as described above, this laser marking device L can mark a sheet-like flexible workpiece W using the laser light (hereinafter, "flexible workpiece" will be simply referred to as "workpiece"). This marking is performed in accordance with a pre-set printing pattern Pp, etc.

The irradiation area R1 referred to here is an area set on the surface of the workpiece W, and is an area corresponding to the printing surface that is pre-assigned to the set plane R2 on the display unit 102. The irradiation area R1 as the printing surface can take various forms depending on the relative positional relationship between the laser marking device L and the workpiece W, the specifications of the laser marking device L, the movement path of the workpiece W, etc. For example, the irradiation area R1 of a workpiece W moving along a two-dimensional plane will be a plane that follows the movement path. On the other hand, the irradiation area R1 of a workpiece W moving in three-dimensional space can be a curved surface that follows the movement path.

In addition, the printing pattern Pp in the following description includes not only character patterns to be marked on the workpiece W, but also graphic patterns to be marked on the workpiece W, such as ":", "x", barcodes, and QR codes (registered trademarks).

In particular, the laser marking device L according to this embodiment can emit laser light having a wavelength of around 350 nm as laser light for processing the workpiece W. This wavelength is included in the ultraviolet wavelength range. Therefore, in the following description, the laser light for processing the workpiece W will sometimes be referred to as "UV laser light" to distinguish it from other laser light, such as near-infrared light.

The following describes a case where the marking target is a workpiece W made of a sheet-like film (the aforementioned "flexible workpiece"), and the film contains a UV-reactive layer (not shown) that chemically reacts with UV laser light.

The workpiece W in this disclosure may be made of a plastic film, a film containing an aluminum layer, a film containing an aluminum vapor deposition layer, or a film containing a paper layer. The workpiece W can be made of films made of various materials. The film that makes up the workpiece W may also have a three-layer structure, or a multi-layer structure with three or more layers.

Also, as shown in FIG. 1, the workpiece W according to this embodiment is composed of multiple workpiece elements We arranged along a predetermined conveying direction At. The workpiece elements We may be integrally connected along the conveying direction At, or may be arranged at intervals in the conveying direction At. Each workpiece element We is individually marked by a laser marking device L. The workpiece elements We can also be described as multiple processed areas or printed areas set on the surface of the workpiece W and arranged at equal intervals along the conveying direction At.

Here, in order to apply similar markings to each of the multiple workpiece elements We, it is possible to detect the relative position of each workpiece element We with respect to the marker head 1 each time. For this purpose, alignment marks Mr are provided on the surface of the workpiece W at equal intervals along the transport direction. As shown in Figure 1, each alignment mark Mr may be provided in a location between workpiece elements We lined up in the transport direction At. Alternatively, each alignment mark Mr may be provided on one side of each workpiece element We in the transport width direction (the +X side or -X side in Figure 1) (not shown).

In addition, the laser marking device L according to this embodiment is configured to perform so-called two-dimensional printing by scanning the laser light in two dimensions, but because this laser marking device L is configured to have a deeper focal depth than conventional products, it can also perform so-called three-dimensional printing. Therefore, this laser marking device L can even mark workpieces W that are transported along a three-dimensional movement path.

As shown in Figures 1 and 2, the laser marking device L according to this embodiment includes a marker head 1 and a marker controller 100. In this embodiment, the marker head 1 and the marker controller 100 are separate entities and connected by a cable 200. The cable 200 according to this embodiment may be configured by bundling together at least a portion of the electrical wiring for transmitting power from inside the marker controller 100 to the marker head 1, and the signal wiring for transmitting and receiving analog signals, digital signals, etc.

(Marker Controller 100)
The marker controller 100 has a controller main body 100a for controlling the marker head 1, and a user terminal 100b for accepting various inputs from the user.

Of these, the controller main body 100a can scan the laser light over the surface of the workpiece W by controlling the marker head 1 according to settings related to the print pattern Pp, for example. The controller main body 100a has a memory device 120 for storing these settings. This memory device 120 is made up of a combination of volatile memory and/or non-volatile memory.

For example, the controller main body 100a is equipped with a marking control unit 109, as shown in FIG. 2, as a functional element for controlling the marker head 1. This marking control unit 109 is electrically connected to the laser light generating unit 2 and laser light scanning unit 3 (described below) in the marker head 1, and by controlling these, it is possible to mark the workpiece W using laser light. Other details of the controller main body 100a will be described later.

On the other hand, the user terminal 100b has, for example, a central processing unit (CPU) and memory, and is connected to the controller main body 100a via wire or wirelessly so as to be able to send and receive electrical signals.

In particular, the user terminal 100b according to this embodiment can be configured as a touch panel console. The user terminal 100b can be configured separately from the controller main body 100a, or can be configured as an integrated unit. If configured separately, the user terminal can be configured as a tablet terminal, desktop computer, laptop computer, etc., instead of a touch panel console.

The user terminal 100b functions as a terminal for setting various printing conditions and presenting information related to marking on the workpiece W to the user. This user terminal 100b is equipped with a display unit 102 for displaying information to the user, an operation unit 101 for accepting operation inputs from the user, and a storage device (not shown) for storing various information. The user terminal 100b may also be called a print setting device for setting various printing conditions. The marker head 1 and marker controller 100 may also be collectively called a laser marker.

The display unit 102 can display a setting plane R2 defined by Cartesian coordinates. This display unit 102 is an example of a "display means" in this embodiment. Also, as shown in FIG. 1, an input interface Iu that accepts input of characters to be marked (hereinafter referred to as "print pattern Pp") is arranged on the setting plane R2 displayed by the display unit 102. This input interface Iu consists of user interfaces such as a frame indicating the range of the setting plane R2 and a graphic that indicates the position of the print pattern Pp on the setting plane R2, and can accept input of the print pattern Pp based on operation input to the operation unit 101 and display the contents of the accepted print pattern Pp on the setting plane R2.

Specifically, the display unit 102 can be configured as a liquid crystal display or an organic EL panel. If the user terminal 100b is incorporated into the controller main body 100a or a touch panel console is used, the display screen provided on the controller main body 100a or the console can serve as the display unit.

The operation unit 101 can be composed of a keyboard and a pointing device. Pointing devices include a mouse, joystick, etc. If the user terminal 100b is incorporated into the controller main body 100a or a touch panel console is used, the operation unit can be a switch, button, or the display itself provided on the controller main body 100a or the console.

The user terminal 100b configured as described above can set printing conditions for marking based on operational input by the user. These printing conditions include details of the printing pattern Pp, as well as the target output of the laser light (laser power) and the scanning speed of the laser light on the workpiece W (scan speed).

The printing conditions set by the user terminal 100b are output to the controller main unit 100a and stored in the memory device 120 of the controller main unit 100a. If necessary, the printing conditions may also be stored in the memory device of the user terminal 100b.

(Marker head 1)
On the other hand, the marker head 1 is electrically connected to the marker controller 100. The marker head 1 can communicate with the marker controller 100 via wire or wirelessly, and is controlled by the marker controller 100 to emit UV laser light toward the irradiation area R1.

The marker head 1 according to this embodiment is installed on processing equipment 500, which processes a workpiece W made of a sheet-like film. As shown in FIG. 3, this processing equipment 500 includes a support member 501 that supports the marker head 1 and a transport roller 502 around which the workpiece W is wrapped.

As shown in Figures 11 and 12, the processing equipment 500 further includes two rail members 503l and 503r that slidably support the marker head 1 via the support member 501, two fixed members 505 and 506 to which the ends of the two rail members 503l and 503r are attached, and a first driven roller 504l and a second driven roller 504r that are driven when the workpiece W is transported by the transport roller 502.

In this way, the workpiece W in this embodiment can be transported while wrapped around the transport roller 502, and the transport roller 502 used in this case may be positioned so that it overlaps with the irradiation area R1 in the vertical direction (Z direction, described below), as shown in Figure 11, for example.

Furthermore, as shown in FIG. 11, the center line Ar, which passes through the rotation axis of the conveying roller 502 and extends in the Z direction, is offset upstream or downstream relative to the laser emission axis Al, which will be described later. In other words, the laser emission axis Al, which extends in the Z direction, and the rotation axis of the conveying roller 502, which extends in the X direction, are laid out so that they do not intersect with each other.

As shown in Figure 3, the support member 501 can mount the laser marking device L, particularly the housing 10 of the marker head 1, at a predetermined mounting position. As an example of the configuration of the support member 501 shown in Figures 1 and 3, the housing 10 can be suspended from above. In particular, the housing 10 according to this embodiment is designed to be suspended from its top surface 10u.

On the other hand, the transport roller 502 is cylindrical with a central axis extending in the short direction of the workpiece W. In this case, the workpiece W is transported in the long direction along a predetermined movement path by the rotation of the transport roller 502.

Here, as shown in the upper and lower diagrams of Figure 3, the processing equipment 500 according to this embodiment is shared between the marker head 1 according to this embodiment and a printing device 1001 that prints using a method other than laser light marking.

In other words, the marker head 1 according to this embodiment is configured to be attached in place of the printing device 1001 to the support member 501 of the processing equipment 500 configured to mount the printing device 1001.

An example of a printing device 1001 that can replace the marker head 1 is a thermal transfer overprinter (TTO), but it can also be replaced with other printing devices 1001.

In more detail, the replaceable printing device 1001 as described above may be, for example, one that includes a housing 1010 configured in a roughly rectangular parallelepiped shape and that includes a printing surface 1010d that exposes the printing section 1006 that contacts the printing area on the workpiece W, and a connection surface 1010u that is a surface different from the printing surface 1010d and that can be connected to the support member 501.

In this case, as shown in the upper and lower diagrams of Figure 3, the marker head 1 is supported by a support member 501 that can be connected to the connection surface 1010u, similar to the printing device 1001. The supported marker head 1 marks the workpiece W by irradiating UV laser light toward the irradiation area R1 that is set corresponding to the printing area (the area that comes into contact with the printing unit 1006 in the printing device 1001).

The laser marking device L according to this embodiment is also configured with an imaging device 92 for capturing images of the marking results. This imaging device 92 is located on the exterior surface of the housing 10 of the marker head 1 or inside the housing 10, and is capable of capturing images of the surface of the workpiece W. This imaging device 92 is electrically connected to the image sensor 404, which is part of the external device 400. This imaging device 92 can be attached to the housing 10 of the marker head 1 via, for example, a camera attachment 91 as shown in FIG. 13.

Specifically, the imaging device 92 according to this embodiment is configured as a line scan camera having an imaging field of view extending along the transport width direction (X direction in Figure 1), which is perpendicular to the transport direction At. The use of a line scan camera is particularly effective when performing moving printing, which will be described later.

The external device 400 is connected to the marker controller 100 as needed. In the example shown in FIGS. 1 and 2, the external device 400 is composed of an encoder 401, a programmable logic controller (PLC) 402, a mark detection sensor 403, and the image sensor 404 described above. Of these devices, the encoder 401 is connected to the marker controller 100 via the first interface unit 106. Similarly, the PLC 402 is connected to the marker controller 100 via the second interface unit 107, and the mark detection sensor 403 is connected to the marker controller 100 via the third interface unit 108. Although not shown, the image sensor 404 may be connected to the marker controller 100 via a so-called "fourth interface unit," or the image sensor 404 may be connected to the PLC 402 via an interface unit external to the laser marking device L.

Hereinafter, the first interface unit 106, the second interface unit 107, and the third interface unit 108 may be referred to as the first IF unit 106, the second IF unit 107, and the third IF unit 108, respectively.

In this embodiment, the encoder 401 is configured as a rotary encoder and is capable of detecting the transport speed of the workpiece W. The encoder 401 outputs a signal (detection signal) indicating the detection result to the marker controller 100. The marker controller 100 controls the two-dimensional scanning of the laser light, etc., based on the detection signal input from the encoder 401.

As shown in FIG. 1, the encoder 401, which is a rotary encoder, is arranged to rotate its own wheel in conjunction with the rotation of the conveying roller 502. The encoder 401 is configured to convert the rotation of its wheel into a pulse signal (known as an "encoder pulse") and output it.

PLC 402 is configured, for example, by a microprocessor and can input control signals to marker controller 100. PLC 402 is used to control laser marking system S according to a predetermined sequence.

The mark detection sensor 403 is configured, for example, by a light-receiving type photoelectric sensor (a so-called color sensor), and is capable of detecting the position of the alignment mark Mr attached to the surface of the workpiece W. The mark detection sensor 403 outputs a signal (trigger signal) indicating the detection signal to the marker controller 100. The marker controller 100 controls the start timing of marking, etc., based on the trigger signal input from the mark detection sensor 403.

The image sensor 404 is electrically connected to the imaging device 92 and receives an image signal (a signal indicating the image capture result by the imaging device 92) generated by the imaging device 92. Based on the input image signal, the image sensor 404 inspects the markings made by the laser marking device L and processed on the surface of the workpiece W. In doing so, inspection may be performed based on the shape, color, gloss, etc. of the marking, or, in the case of marking text, inspection may be performed using an OCR (Optical Character Reader). The inspection log generated by the image sensor 404 may be stored in the image sensor 404 itself, or in the storage device 120 of the marker controller 100. Details of the processing related to the imaging device 92 and image sensor 404 will be described later with reference to specific examples of control processes.

The image sensor 404 may be incorporated into the marker controller 100. In other words, by directly connecting the imaging device 92 and the marker controller 100, the functions that should be performed by the image sensor 404 can be performed by the marker controller 100.

In addition to the above-mentioned devices and equipment, the laser marking device L can be connected wirelessly or via wire to devices for operation and control, computers for performing various other processes, storage devices, peripheral devices, etc.

<Marker head 1>
Fig. 4 is a perspective view illustrating the appearance of the marker head 1, and Fig. 5 is a view corresponding to Fig. 4 illustrating the state in which the cover member 13 has been removed from the marker head 1. Fig. 6 is a side view of the marker head 1, and Fig. 7 is a perspective view illustrating the state in which the cover member 13 has been removed from the marker head 1. Figs. 8 and 9 are perspective views illustrating the housing structure of the marker head 1, and Fig. 10 is a cross-sectional view that schematically illustrates the internal structure of the marker head 1.

Furthermore, Figure 13 is a perspective view illustrating the configuration of the camera mounting portion 19 and camera unit 9, Figure 14 is a diagram illustrating a schematic example of the relationship between the imaging optical axis Ax and the internal space (optical path partition H3), and Figure 15 is a diagram illustrating a schematic example of the relationship between the illumination area R1 and the imaging area R3.

(Schematic configuration of marker head 1)
2, the marker head 1 includes, as its main components, a laser light generating unit 2 and a laser light scanning unit 3. The laser light generating unit 2 generates laser light (e.g., UV laser light) based on power supplied from outside the marker head 1. The laser light scanning unit 3 reflects the laser light generated by the laser light generating unit 2 in a desired direction, thereby scanning the laser light over the surface of the workpiece W.

The marker head 1 also includes a housing 10 that houses the aforementioned components, namely the laser light generation unit 2 and the laser light scanning unit 3. The housing 10 has an exit window 4 that transmits the laser light reflected by the laser light scanning unit 3. While details are omitted, the housing 10 has a roughly rectangular parallelepiped outer shape and includes an exit surface 10d on which the exit window 4 is formed, and a mounting surface 10u that is different from the exit surface 10d and can be connected to a support member 501. The mounting surface 10u is connected to the support member 501 via an attachment 5 (see Figure 3). In this embodiment, the mounting surface 10u is composed of a top surface 10u that faces the exit surface 10d in the Z direction.

(Laser light generating unit 2)
The laser light generating unit 2 generates excitation light in accordance with the power supplied via the cable 200. The excitation light source 21 for generating the excitation light may be, for example, a laser diode. This excitation light source 21 may be housed in the marker controller 100 instead of the housing 10. In that case, a part of the laser light generating unit is housed in the marker controller 100, and the other part is housed in the housing 10.

The laser light generating unit 2 also has a solid-state laser crystal 22 that generates a fundamental wave based on the generated excitation light, and a nonlinear optical crystal (not shown) that generates UV laser light by modulating the fundamental wave.

For example, a rod-shaped Nd:YVO ₄ (yttrium vanadate) can be used as the solid-state laser crystal 22. The fundamental wave can be generated by any method, such as a one-directional excitation method using end pumping.

The nonlinear optical crystal can be composed of multiple optical crystals, such as an optical crystal for generating the second harmonic and an optical crystal for generating the third harmonic. Various optical materials can be used for each optical crystal.

(Laser light scanning unit 3)
The laser light scanning unit 3 is configured using a so-called two-axis (X-axis and Y-axis) galvanometer scanner, and has a first scanner 31 that drives a first mirror 31a to scan the laser light in the Y direction, a second scanner 32 that drives a second mirror 32a to scan the laser light in the X direction, and a control board 33 that controls each part of the laser light scanning unit 3 (shown only in Figure 10).

The laser light scanning unit 3 drives the first scanner 31 and the second scanner 32 according to pre-created print data, polarizing the laser light generated by the laser light generating unit 2 so that it is irradiated toward the irradiation area R1. The deflected laser light then passes through the exit window 4 and is irradiated onto the irradiation area R1.

(Outer surface of the housing 10)
As shown in Fig. 4, the housing 10 of the marker head 1 is configured as a roughly rectangular parallelepiped with a longer dimension in the front-to-rear direction (the direction from the right and front side to the left and depth side in Fig. 4) than in the left-to-right direction (the direction from the left and front side when viewed from the front of the housing 10 to the right and depth side when viewed from the front of the housing 10 in Fig. 4). Note that "left and right" in this specification refers to left and right as seen by a user facing the housing 10.

Hereinafter, the front-to-back direction of the housing 10 will be referred to as the X direction, the left-to-right direction as the Y direction, and the height direction as the Z direction. In particular, the depth of the paper in Figure 4 in the X direction will be referred to as the +X direction, and the front side of the paper in Figure 4 will be referred to as the -X direction. Similarly, the front side of the paper in Figure 4 in the Y direction will be referred to as the +Y direction, and the depth side of the paper in Figure 4 will be referred to as the -Y direction. Similarly, the top side of the paper in Figure 4 in the Z direction will be referred to as the -Z direction, and the bottom side of the paper in Figure 4 will be referred to as the +Z direction.

For convenience, the definition given here is based on the external shape of the housing 10, but instead of, or in addition to, this definition, a definition based on the operating direction and positional relationship of each component housed in the housing 10 can also be used.

For example, the direction in which the laser light irradiation position moves when the first mirror 31a is driven can be defined as the Y direction, and the direction in which the laser light irradiation position moves when the second mirror 32a is driven can be defined as the X direction.

In the following description, we will assume that the definition based on the external shape of the housing 10 and the definition based on the irradiation positions of the first mirror 31a and the second mirror 32a are the same.

As shown in Figures 4 to 7, the housing 10 has a bottom surface 10d on which the exit window 4 is formed, and a top surface 10u that faces the bottom surface 10d and therefore the exit window 4. For example, the bottom surface 10d faces the +Z direction, while the top surface 10u faces the -Z direction, and both are made of one or more plate-like members that have a thickness in the Z direction. Note that "facing" here refers to conceptual facing when the housing 10 is considered to be a conceptual rectangular parallelepiped.

The housing 10 further has a bottom surface 10d and a top surface 10u, as well as a front surface 10f, a back surface 10b, a left side surface 10l, and a right side surface 10r that surround the laser light generation unit 2 and the laser light scanning unit 3.

The front surface 10f, rear surface 10b, left side surface 10l, and right side surface 10r all face in a direction perpendicular to the top surface 10u and bottom surface 10d (i.e., in a direction along the XY plane). For example, the front surface 10f faces in the -X direction, while the rear surface 10b faces in the +X direction, and both are made of one or more plate-like members that have a thickness in the X direction. Similarly, for example, the left side surface 10l faces in the +Y direction, while the right side surface 10r faces in the -Y direction, and both are made of one or more plate-like members that have a thickness in the Y direction.

The six sides of the housing 10 will be described in order below. Note that the term "side" in the context of the bottom side 10d, top side 10u, front side 10f, back side 10b, left side side 10l, and right side side 10r also includes plate-like members having a certain thickness. Furthermore, these six sides are merely classified for convenience and do not need to be separate from one another. For example, at least one of the left side side 10l and the right side side 10r and at least a portion of the bottom side 10d (particularly the non-offset portion 18, described below) may be integrally formed.

-Top surface 10u-
As shown in Fig. 4, the top surface 10u of the six surfaces constituting the housing 10 extends along the X and Y directions and is formed as a rectangular plate with a dimension in the X direction longer than that in the Y direction. In this embodiment, the top surface 10u is configured as a mounting surface that is connected to a support member and attached to the mounting position. In this case, the thickness of the top surface 10u is greater than the thicknesses of the left side surface 10l and the right side surface 10r.

The top surface 10u, which serves as the mounting surface, is provided with an attachment 5 that can be attached to a target position. The attachment 5 is configured as a plate-like member that extends in directions (X and Y directions) substantially parallel to the top surface 10u and has a thickness in a direction (Z direction) perpendicular to the top surface 10u. The attachment 5 is placed on the top surface 10u and, as shown in Figure 10, is fastened to the top surface 10u with fasteners 5b such as bolts. As mentioned above, the thickness of the top surface 10u is greater than the thicknesses of the left side surface 10l, right side surface 10r, etc. Increasing the thickness of the top surface 10u is advantageous in ensuring an insertion clearance for the fasteners 5b.

The top surface of the attachment 5 has fastening holes 5a that correspond to the support member 501 that will be placed at the mounting position. With the support member 501 placed on the attachment 5, the support member 501 can be attached to the attachment 5 by fastening a fastener such as a bolt into the fastening holes 5a. This allows the top surface 10u to be attached to the mounting position via the attachment 5, and simultaneously allows the housing 10 to be suspended from the support member 501.

-Bottom 10d-
6, the bottom surface 10d of the six surfaces is disposed on the opposite side of the top surface 10u across the laser light scanning unit 3. As shown in FIG. 7, the bottom surface 10d is formed in a curved shape that extends along the X direction and has a central portion in the Y direction recessed toward the −Z side.

Specifically, as shown in Figures 7 and 10, the bottom surface 10d according to this embodiment has an offset portion 16a located in the center in the Y direction and offset toward the -Z side, an inclined portion 16b also located in the center in the Y direction, and non-offset portions 18 located at both ends in the Y direction and protruding toward the +Z side compared to the offset portion 16a. Both the offset portion 16a and the non-offset portion 18 are formed to extend substantially flat along the X direction.

In detail, the bottom surface 10d according to this embodiment has an offset portion 16a as its upper base and a groove with a trapezoidal cross section that widens toward the +Z side. The exit window 4 is provided in the offset portion 16a, which serves as the upper base. The bottom surface 10d according to this embodiment is configured as an exit surface on which the exit window 4 is formed. Details of the exit window 4 will be described later.

More specifically, as shown in FIG. 6, the center of the bottom surface 10d in the Y direction is configured by connecting an offset portion 16a located on the -X side with an inclined portion 16b located on the +X side. Of these, the offset portion 16a according to this embodiment extends flatly from the center of the bottom surface 10d in the Y direction toward the +X side, as shown in FIGS. 6, 7, and 9.

Sloped portion 16b is also located in the center of bottom surface 10d in the Y direction, and extends at an angle from the +X side end of offset portion 16a toward the +X side. This sloped portion 16b slopes toward the +Z side as it approaches the +X side, and is arranged so as to be inclined with respect to the X and Z directions and to form a plane parallel to the Y direction. As shown in Figure 7, the +X side end of sloped portion 16b is set to be at approximately the same height as the +Z side end of non-offset portion 18.

The surface of the inclined portion 16b forms an inclined surface 16c facing the -X side and the +Z side, and this inclined surface 16c is configured to be able to mount a reflecting mirror 71, as shown in Figure 7 and elsewhere. This inclined surface 16c is an example of the "mirror mounting portion" in this embodiment. As shown in Figure 14, the reflecting mirror 71 intersects with the imaging optical axis Ax of the imaging device 92 described above and can reflect the imaging optical axis toward the illumination area R1.

Furthermore, the reflecting mirror 71 according to this embodiment is made of stainless steel (also known as SUS) that has been subjected to a mirror finish. By using stainless steel, cracks in the reflecting mirror 71 can be reduced.

On the other hand, the non-offset portion 18 constitutes the portion of the bottom surface 10d that extends from the hypotenuse of the trapezoid to the +Z end. The non-offset portion 18 in this embodiment is composed of a first plate-shaped member 18l located on the +Y side of the offset portion 16a, and a second plate-shaped member 18r located on the -Y side of the offset portion 16a.

As shown in Figure 10, the first plate-shaped member 18l is formed in a thin plate shape and has an inverted L-shape when viewed from the -X side. Here, "inverted L-shape" refers to a shape obtained by inverting an L-shape with respect to an axis of symmetry extending in the Z direction. The first plate-shaped member 18l is disposed on the opposite side of the second plate-shaped member 18r across the offset portion 16a. The vertical side of the inverted L-shape of the first plate-shaped member 18l forms the oblique side on the +Y side of the trapezoid, and the horizontal side of the inverted L-shape forms the +Z side end of the +Y side.

As shown in Figure 10, the second plate-shaped member 18r is formed in a thin plate shape and is L-shaped when viewed from the -X side. The second plate-shaped member 18r is positioned on the opposite side of the first plate-shaped member 18l, with the offset portion 16a sandwiched between them. The vertical side of the L-shape of the second plate-shaped member 18r forms the oblique side on the -Y side of the trapezoid, and the horizontal side of the L-shape forms the +Z side end of the -Y side.

Also, as shown in FIG. 10, the first plate-shaped member 18l, together with the lower half of the left side surface 10l, covers the exit window 6 from the +Y side. Meanwhile, the second plate-shaped member 18r, together with the lower half of the right side surface 10r, covers the exit window 6 from the -Y side. In this way, the first plate-shaped member 18l and the second plate-shaped member 18r, together with the lower half of the left side surface 10l and the lower half of the right side surface 10r, form a skirt-shaped cover (skirt portion).

-Front 10f-
As shown in Figures 4, 5 and 7, the front surface 10f of the six surfaces extends along the YZ direction and is formed in a plate shape having an indicator 11, two ventilation holes 12, 12, and a notch 10c.

The indicator 11 is located near the upper right edge of the front surface 10f and consists of three lamps 11a, 11b, and 11c aligned in the Y direction (see Figure 7). Each of the three lamps 11a, 11b, and 11c is composed of a light-emitting diode (LED) electrically connected to the marker controller 100.

As shown in Figures 5 and 7, one of the two ventilation holes 12, 12 is located on the lower side of the front face 10f near the left end, and the other of the two ventilation holes 12, 12 is located on the lower side of the front face 10f near the right end. Both of the two ventilation holes 12, 12 penetrate the front face 10f in the thickness direction, and each communicates with the second storage section H2, which will be described later.

As shown in Figures 5A and 7, the cutout 10c is formed by cutting out a portion of the front surface 10f that includes the lower end, and is connected to the front end (the end on the -X direction side) of the offset portion 16a. The cutout 10c is positioned between the two air vents 12, 12 in the Y direction.

More specifically, the notch 10c is formed in a generally trapezoidal shape that tapers in diameter in the +Z direction so that its cross section roughly matches the cross section of the trapezoid with the offset portion 16a as its upper base. The front surface 10f in this embodiment is configured as an at least partially open user-access surface (open surface) that leads to the exit window 4 via the offset portion 16a, due to the provision of the notch 10c in its lower half.

In addition, a cover member 13 capable of closing the cutout 10c on the front surface 10f, which serves as the open surface, is attached (see Figures 4 and 6). The cover member 13 can be used to replace an existing front cover (for example, a cover equipped with a hinge that can open and close the cutout 10c). Details of the cover member 13 will be described later.

-Back side 10b-
4 to 6 , the rear surface 10b, one of the six surfaces, is disposed on the opposite side of the laser beam scanning unit 3 from the front surface 10f, and is formed in a plate shape extending along the YZ direction. The rear surface 10b according to this embodiment can be regarded as one outer surface of the housing 10 (an outer surface different from the cover member 13), and serves as a connection surface to which a cable 200 that supplies power to the inside a of the housing 10 is connected. The rear surface 10b as a connection surface surrounds the laser beam scanning unit 3 together with the front surface 10f as an open surface, the top surface 10u as a mounting surface, and the bottom surface 10d as an emission surface.

As shown in Figure 6, a connection cover 14 is provided on the rear surface 10b, which serves as the connection surface, to cover the connection portion between the rear surface 10b and the cable 200. This connection cover 14 restricts the extension direction of the cable 200 so that the cable 200 is unwound in the in-plane direction (YZ direction) of the rear surface 10b.

-Left side 10l-
As shown in FIGS. 4, 5 and 10, the left side surface 10l of the six surfaces is disposed on the +Y side with respect to the laser light scanning unit 3, and is formed in a plate shape extending along the ZX direction.

-Right side 10r-
7 and 10, the right side surface 10r of the six surfaces is disposed on the -Y side with respect to the laser beam scanning unit 3, and is formed in a plate shape extending along the ZX direction. The right side surface 10r is disposed on the opposite side of the left side surface 10l with the laser beam scanning unit 3 in between.

(Internal space of the housing 10)
The housing 10 defines an internal space surrounded by six sides: a bottom side 10d, a top side 10u, a front side 10f, a rear side 10b, a left side side 10l, and a right side side 10r. This internal space is divided into multiple storage sections by plate-like members arranged inside the housing 10.

The marker head 1 according to this embodiment has a first base plate 15, a second base plate 16, and a third base plate 17 as such plate-like members. In this embodiment, the first base plate 15, the second base plate 16, and the third base plate 17 are separate from one another. Of these plate-like members, the first base plate 15 is configured as a support plate capable of supporting a solid-state laser crystal 22.

The structure of each plate-shaped member will be explained in order below.

-First base plate 15-
8, 9, and 10, the first base plate 15 is configured as a metal plate-like member extending in the X direction and is housed in the housing 10 (in other words, it is surrounded by six sides of the housing 10). The thickness of the first base plate 15 is set to be greater than the thickness of at least the left side surface 10l and the right side surface 10r of the six sides of the housing 10.

In particular, the first base plate 15 according to this embodiment has an inverted L-shape when viewed from the -X side. Here, "inverted L-shape" refers to a shape obtained by inverting an L-shape with respect to an axis of symmetry extending in the Z direction. Hereinafter, the portion of the first base plate 15 corresponding to the vertical side of the inverted L-shape may be referred to as the vertical side portion 15a, and the portion corresponding to the horizontal side of the inverted L-shape may be referred to as the horizontal side portion 15b.

The first base plate 15 is disposed between the left side surface 10l and the right side surface 10r in the Y direction, and is disposed on the +Y side of the second base plate 16. The first base plate 15 is disposed on the +Y side of the third base plate 17, sandwiching the second base plate 16 between them. The first base plate 15 is disposed below the top surface 10u in the Z direction. The first base plate 15 is disposed between the front surface 10f and the back surface 10b in the X direction.

The first base plate 15, which serves as a support plate, is attached to the housing 10 via the front surface 10f and back surface 10b, while remaining separate from the top surface 10u, which serves as the mounting surface.

Next, to describe the vertical side portion 15a in more detail, the vertical side portion 15a in this embodiment is formed in the shape of a thick plate that extends along the Z direction, which is the irradiation direction, and the X direction.

Of the two left and right side surfaces of the vertical side portion 15a, the left side surface facing the +Y side forms a partition surface that separates the crystal housing section H12, which will be described later. Various optical components, including the solid-state laser crystal 41, are fastened to this partition surface.

Furthermore, of the left and right side surfaces of the vertical side portion 15a, the right side surface facing the -Y side supports the first casing 50, which defines the mirror housing section H11 (described below), from the left. Instead of supporting the first casing 50 with this right side surface, this right side surface may also define part of the mirror housing section H11.

Next, to describe the horizontal side portion 15b in more detail, the horizontal side portion 15b in this embodiment is formed as a thick plate extending in the X and Y directions. As shown in Figure 10, a first heat sink 81, which serves as a heat sink in this embodiment, is provided on the underside of the horizontal side portion 15b.

The first heat sink 81 is composed of multiple fins that protrude in the +Z direction. These fins are aligned in the Y direction. Each fin is formed to extend in the X direction. The first heat sink 81 is thermally coupled to a part of the laser light generation unit 2 (specifically, the solid-state laser crystal 22) via the first base plate 15.

In the example shown in Figure 10, the horizontal side portion 15b and the first heat sink 81 are formed integrally, but this is not limiting; the horizontal side portion 15b and the first heat sink 81 may also be formed separately.

- Second base plate 16 -
As shown in Figures 8, 9, and 10, the second base plate 16 is configured as a metal plate-like member extending in the X direction, and defines some of the six surfaces of the housing 10, particularly the offset portion 16a and the inclined portion 16b on the bottom surface 10d.

In particular, the second base plate 16 according to this embodiment is formed in a Z-shape when viewed from the -Y side. When the second base plate 16 is considered to be Z-shaped, the upper edge corresponds to the offset portion 16a, and the edge connecting the upper edge and the bottom edge corresponds to the inclined portion 16b. In the X direction, the length of the offset portion 16a as the upper edge is set to be longer than the length of the bottom edge when the second base plate 16 is considered to be Z-shaped.

The second base plate 16 is disposed between the left side surface 10l and the right side surface 10r in the Y direction, more specifically, between the first base plate 15 and the third base plate 17.

The second base plate 16 is positioned below the top surface 10u in the Z direction. The second base plate 16 is positioned on the -Z side of the horizontal side 15b of the first base plate 15. Specifically, on the second base plate 16, the offset portion 16a, which serves as the upper side of the Z shape, is positioned at approximately the same Z position as the +Z side portion (lower portion) when the vertical side 15a of the first base plate 15 is divided in half in the Z direction. Furthermore, on the second base plate 16, the portion corresponding to the bottom of the Z shape is positioned at approximately the same Z position as the +Z side ends (lower ends) of the left side surface 10l and right side surface 10r.

The second base plate 16 is disposed between the front surface 10f and the rear surface 10b in the X direction. The second base plate 16 is fixed to the front surface 10f and the rear surface 10b via the first base plate 15 and the third base plate 17. The second base plate 16 may also be directly fastened to the front surface 10f and the rear surface 10b.

Next, to explain the offset portion 16a in more detail, the offset portion 16a in this embodiment is formed as a thick plate extending in the X and Y directions. When the offset portion 16a is divided in half in the X direction, the exit window 6 in this embodiment is formed in the +X side (the rear portion in the front-to-rear direction). This exit window 6 is positioned near the boundary between the offset portion 16a and the inclined portion 16b.

The exit window 4 has an exit hole 41 that penetrates the +X side portion of the offset portion 16a, a cover glass 42 that fits into this exit hole 41, and a sealing member (not shown) that liquid-tightly seals the gap between the exit hole 41 and the cover glass 42 (see Figure 10). The cover glass 42 is configured as an optical member that transmits laser light that is reflected by the laser light scanning unit 3 and heads toward the irradiation area R1. This cover glass 42 can be formed in a rectangular shape that corresponds to the shape of the irradiation area R1, for example, a rectangular shape that is approximately similar to the irradiation area R1 but smaller than the irradiation area R1.

Furthermore, as shown in Figures 8, 9, and 10, of the upper and lower surfaces of the offset portion 16a, the upper surface facing the -Z side supports the first casing 50 from below. More specifically, the first casing 50 can be fastened to the upper surface of the offset portion 16a, and this fastening allows the first casing 50 to be fixed to the second base plate 16. Instead of the upper surface of the offset portion 16a supporting the first casing 50, the upper surface may also define part of the mirror housing portion H11.

-Third base plate 17-
8, 9, and 10, the third base plate 17 is configured as a metal plate-like member extending in the X direction and is housed in the housing 10 (in other words, it is surrounded by six sides of the housing 10). The thickness of the third base plate 17 is set to be greater than the thicknesses of at least the left side surface 10l and the right side surface 10r of the six sides of the housing 10.

In particular, the third base plate 17 according to this embodiment has an L-shape when viewed from the -X side. Hereinafter, the portion of the third base plate 17 corresponding to the vertical side of the L-shape may be referred to as the vertical side portion 17a, and the portion corresponding to the horizontal side of the L-shape may be referred to as the horizontal side portion 17b.

The third base plate 17 is positioned between the left side surface 10l and the right side surface 10r in the Y direction, and is positioned on the -Y side of the second base plate 16. The third base plate 17 is positioned on the -Y side of the first base plate 15, with the second base plate 16 in between.

The third base plate 17 is positioned below the top surface 10u in the Z direction.

The third base plate 17 is disposed between the front surface 10f and the rear surface 10b in the X direction. The third base plate 17 is fixed to the front surface 10f and the rear surface 10b by fasteners (not shown).

Next, the vertical side 17a of the third base plate 17 will be described in detail. In this embodiment, the vertical side 17a is formed as a thick plate extending along the -Z direction, which is the irradiation direction, and the X direction. In the Z direction, the dimension of the vertical side 17a of the third base plate 17 is shorter than the dimension of the vertical side 15a of the first base plate 15. This vertical side 17a supports the second base plate 16 from the -Y side.

Next, regarding the horizontal side portion 17b of the third base plate 17, the horizontal side portion 17b in this embodiment is formed as a thick plate extending in the X and Y directions. Various components can be attached to this horizontal side portion 17b. Components that can be attached to the horizontal side portion 17b include the control board 33 of the laser light scanning unit 3. In addition, as shown in FIG. 10, a second heat sink 82, which serves as a heat sink in this embodiment, is provided on the underside of the horizontal side portion 17b facing the -Z side.

The second heat sink 82 is composed of multiple fins that protrude in the +Z direction. These fins are aligned in the Y direction. Each fin is formed to extend in the X direction. This second heat sink 82 is thermally coupled to other parts of the laser light generating unit 2 (specifically, the excitation light source 21) via the third base plate 17.

In other words, in this embodiment, the first heat sink 81 for cooling the solid-state laser crystal 22 is configured separately from the second heat sink 82 for cooling the excitation light source 21.

In the example shown in Figure 10, the horizontal side portion 17b and the second heat sink 82 are formed integrally, but this is not limiting; the horizontal side portion 17b and the second heat sink 82 may also be formed separately.

Furthermore, when the first base plate 15 and the third base plate 17 are separate bodies, as in this embodiment, the first heat sink 81 provided on the first base plate 15 and the second heat sink 82 provided on the third base plate 17 are separate bodies. However, the present disclosure is not limited to such a configuration, and the first heat sink 81 and the second heat sink 82 can also be configured as an integrated unit.

(Outline of the first storage section H1 and the second storage section H2)
As described above, the internal space of the housing 10 is partitioned into a plurality of storage sections by the first base plate 15 , the second base plate 16 , and the third base plate 17 .

As such storage sections, the housing 10 according to this embodiment has a first storage section H1 in which a cover glass 62 serving as an optical member is provided, and a second storage section H2 in which at least a portion of the periphery of the cover glass 62 protrudes beyond the cover glass 62 toward the irradiation area R1 (see dashed line S1 in Figure 10).

The first storage unit H1 and the second storage unit H2 are aligned along the irradiation direction (-Z direction), with the first storage unit H1 located on one side of the irradiation direction (-Z side) and the second storage unit H2 located on the other side of the irradiation direction (+Z side). The boundary between the first storage unit H1 and the second storage unit H2 is defined by the first base plate 15, the second base plate 16, and the third base plate 17.

The first housing unit H1 houses optical components related to the generation of excitation light, the generation of laser light, and the deflection of laser light. Specifically, the first housing unit H1 in this embodiment houses the laser light generation unit 2 and the laser light scanning unit 3.

In the example shown in Figure 10, the first storage section H1 is configured as a space surrounded by the top surface 10u, the upper portion of the front surface 10f, the lower portion of the back surface 10b, the upper portion of the left side surface 10l, the upper portion of the right side surface 10r, the portion of the bottom surface 10d formed by the second base plate 16, the first base plate 15, and the third base plate 17.

On the other hand, the second housing section H2 houses cooling components related to cooling the optical components housed in the first housing section H1. Specifically, the second housing section H2 according to this embodiment houses a first heat sink 81 and a second heat sink 82 that are thermally coupled to the optical components housed in the first housing section H1, as well as blower fans (not shown) for the first heat sink 81 and the second heat sink 82. The crystal-side housing section H21 and the light source-side housing section H22, which serve as a pair of extensions, define the housing spaces for the first heat sink 81 and the second heat sink 82.

(Details of the first storage section H1)
Here, of the first housing section H1 and second housing section H2 described above, the first housing section H1 is further divided into three housing sections aligned in directions (X and Y directions) perpendicular to the irradiation direction, for example, along the Y direction. Specifically, the housing 10 according to this embodiment has a mirror housing section H11, a crystal housing section H12, and a substrate housing section H13.

The mirror housing section H11 houses the first mirror 31a and second mirror 32a of the laser light scanning unit 3. In this embodiment, the mirror housing section H11 is defined by a first casing 50 that can airtightly seal the first mirror 31a and second mirror 32a. As described above, the first casing 50 may be defined using an offset portion 16a.

The crystal housing section H12 is defined by a support plate (first base plate 15) having a partition surface 15g extending along the irradiation direction, and is positioned on the opposite side of the partition surface 15g from the mirror housing section H11 (the +Y side in the illustrated example) to house a solid-state laser crystal 22. The crystal housing section H12 houses some of the optical components that make up the laser light generation section 2, such as the solid-state laser crystal 22. The crystal housing section H12 is defined by a second casing 40 that can hermetically seal these optical components. The crystal housing section H12 of this embodiment can house nonlinear optical crystals and the like in a sealed state.

The substrate housing section H13 is located on the opposite side of the mirror housing section H11 from the crystal housing section H12, and houses the control board 33. In this embodiment, the substrate housing section H13 is defined as the internal space of the first housing section H1 excluding the mirror housing section H11 and the crystal housing section H12.

(Details of the second storage section H2)
On the other hand, the second housing H2 is partitioned into the +Z side portion of the housing 10 by a first plate-like member 18l and a second plate-like member 18r. The second housing H2 has two spaces spaced apart in a direction perpendicular to the irradiation direction, for example, in the arrangement direction (Y direction) of the mirror housing H11, the crystal housing H12, and the substrate housing H13.

The second housing section H2 in this embodiment has two such spaces: a crystal-side housing section H21 and a light source-side housing section H22. Because the crystal-side housing section H21 and the light source-side housing section H22 are spaced apart in the Y direction, a space that does not belong to the second housing section H2 is separated between the crystal-side housing section H21 and the light source-side housing section H22.

In this embodiment, the first plate-shaped member 18l and the second plate-shaped member 18r are configured to separate the second storage section H2, which serves as a space for storing the members, as well as a space that includes the optical path of the laser light connecting the first mirror 31a (scanner mirror) and the irradiation area R1, which is closer to the irradiation area R1 (the optical path on the +Z side). Hereinafter, this space will be referred to as the "optical path partition section" and will be denoted by the symbol H3. The optical path partition section H3 in this embodiment is configured as a space surrounded on three sides, the +Y side, the -Y side, and the -Z side, by the first plate-shaped member 18l, the second plate-shaped member 18r, and the cover glass 62.

In the illustrated example, the optical path partition H3 is configured as an open space at the lower end on the +Z side, but this configuration is not limited to this. The +Z side end of the optical path partition H3 may be covered with an optical member such as glass. The optical member covering the +Z side end of the optical path partition H3 may be provided alternatively to the cover glass 62, or may be used in combination with the cover glass 62.

Of the two spaces that make up the second housing section H2, the crystal-side housing section H21 houses a first heat sink 81. In this embodiment, the first heat sink 81 is thermally coupled to at least the solid-state laser crystal 22 attached to the first base plate 15, among the optical components that make up the laser light generation section 2.

The light source-side housing H22 houses a second heat sink 82. In this embodiment, the second heat sink 82 is thermally coupled to at least the excitation light source 21 attached to the third base plate 17, among the optical components housed in the substrate housing H13.

(Configuration related to the layout of the imaging device)
The laser light generated by the laser light generation unit 2 is reflected in turn by the second mirror 32a and the first mirror 31a of the laser light scanning unit 3. The laser light reflected by the first mirror 31a is transmitted through a defocus lens 37 shown in FIG. 10 and other figures. This defocus lens 37 is configured to diffuse the laser light transmitted through the lens 37 in an outward direction perpendicular to the irradiation direction. In the present embodiment, when the Z direction is the irradiation direction, the outward diffusion direction is a direction along the XY plane.

Specifically, the defocus lens 37 can be configured, for example, from a single biconcave lens. In this case, the defocus lens 37 is fitted into the through-hole of the first casing 50 with its central axis aligned in the Z direction.

The defocusing lens 37 is also arranged on a straight line connecting the first mirror 31a and the center of the cover glass 42 at the exit window 4. The defocusing lens 37 is arranged between the first mirror 31a and the cover glass 32 in the Z direction (in other words, on the +Z side of the first mirror 31a and the -Z side of the cover glass 42).

The defocusing lens 37 is further positioned so that its optical axis is coaxial with the optical axis of the cover glass 42. Hereinafter, the optical axes of the defocusing lens 37 and the cover glass 42 will be collectively referred to as the "laser emission axis," which will be denoted by the symbol Al (see also Figure 6). This laser emission axis Al extends along the Z direction and is offset toward the +Y side relative to the second mirror 32a, while intersecting with the mirror surface of the first mirror 31a. Because the laser emission axis Al is configured to approximately coincide with the optical axis of the laser light reflected by the first mirror 31a, the two axes will be considered to be the same in the following description.

Note that the configuration of the defocus lens 37 as an optical element is not limited to using a single biconcave lens. The optical element may be configured using multiple lenses, or may be configured using lenses other than a biconcave lens.

Here, as shown in FIG. 11, the crystal-side housing H21 and light source-side housing H22 that make up the second housing H2 can be considered to be members extending from the first housing H1 along the irradiation direction (emission direction) of the laser light so as to sandwich the optical axis (laser emission axis Al) of the laser light that has passed through the cover glass 42 as an optical element.

In the following description, these components may be referred to as a "pair of extensions" as a term that takes into account the shapes of the crystal-side housing portion H21 and the light source-side housing portion H22.

The pair of extension portions H21, H22 can be classified into a first extension portion (crystal-side housing portion) H21, which is located on one side (+Y side) of the first direction (Y direction) with respect to the laser emission axis Al, and a second extension portion (light source-side housing portion) H22, which is located on the other side (-Y side) of the first direction across the laser emission axis Al. As shown in Figures 10 and 11, the second extension portion H22 is spaced apart in the Y direction from the first extension portion H21.

As mentioned above, the pair of extension portions H21, H22 form the optical path partition portion H3 as an internal space. This optical path partition portion H3 is formed in the space between the first extension portion H21 and the second extension portion H22.

As shown in FIG. 7, the first extension portion H21 and the second extension portion H22 are connected by the inclined portion 16b, which serves as a wall portion. The inclined portion 16b, which serves as a wall portion, forms the optical path dividing portion H3 together with the first extension portion H21 and the second extension portion H22. The cover member 13 also forms the optical path dividing portion H3 together with the first extension portion H21 and the second extension portion H22. The cover member 13 is positioned so as to face the inclined portion 16b in the X direction.

More specifically, the cover member 13 in this embodiment is formed in the shape of a rectangular plate that can cover the area from the upper half of the front surface 10f to the cutout 10c in the lower half. The cover member 13 is fixed to the front surface 10f with fasteners such as screws.

The cover member 13 has a through-hole (number omitted) formed in approximately the same position as the indicator 11, and two through-holes (number omitted) formed in approximately the same positions as the two air vents 12, 12. A detailed description of these through-holes will be omitted.

Furthermore, the lower half of the cover member 13 is provided with a camera mounting section 19 to which the aforementioned imaging device 92 can be attached. This camera mounting section 19 is composed of a first opening (aperture) 19a formed in a position facing the inclined section (wall section) 16b on which the reflective mirror 71 is disposed, and a second opening 19b for mounting a camera mounting fixture 91 as shown in FIG. 13.

As shown in Figures 13 and 14, the camera mounting portion 19 according to this embodiment is configured to allow mounting of an imaging device 92 so that the imaging optical axis Ax passes through the optical path partition H3 formed by the pair of extension portions H21, H22.

More specifically, the camera mounting portion 19 in this embodiment is configured to be able to mount a camera unit 9 equipped with an imaging device 92, and is configured to support the imaging device 92 via this camera unit 9.

As shown in FIG. 13, the camera unit 9 includes a camera mounting fixture 91, an imaging device 92, and a light 93. The camera mounting fixture 91 is configured as an inverted L-shaped plate member that is mirror-symmetrical with respect to the Y direction of an L-shaped plate member, and has multiple fastening holes 91b at positions corresponding to the first opening 19a. By using the camera unit 9, the relative position of the light 93 with respect to the imaging device 92 is fixed. This makes it easier to position the optical axis of the illumination light with respect to the imaging optical axis Ax, compared to a configuration in which the imaging device 92 and the light 93 are positioned independently.

A portion of the camera mounting fixture 91 protrudes toward the -X side. This protruding portion forms a camera mounting section 91c to which the imaging device 92 can be attached. With the imaging device 92 attached to the camera mounting section 91c, the camera mounting fixture 91 is attached to the camera mounting section 19, completing the attachment of the imaging device 92 to the marker head 1.

A portion of the camera mounting fixture 91 protrudes toward the +X side. This protrusion constitutes a lighting mounting section 91d that is configured to allow the mounting of a lighting 93. When the camera mounting fixture 91 is mounted to the camera mounting section 19 with the lighting 93 attached to the lighting mounting section 91d, the lighting 93 is positioned within the optical path partition section H3, which serves as the internal space, as shown in FIG. 14. As shown in FIG. 13, the lighting 93 is positioned so as to point in a direction that intersects with the imaging optical axis Ax. In particular, the lighting 93 in this embodiment is positioned so as to be perpendicular to both the imaging optical axis Ax and the irradiation direction (Z direction). The lighting of the lighting 93 can be controlled, for example, by the image sensor 404.

In this embodiment, the light 93 is positioned so as to point in a direction intersecting the imaging optical axis Ax. However, the present invention is not limited to this. The light 93 may be positioned so as to point in approximately the same direction as the imaging optical axis Ax. For example, in the camera unit 9' shown in FIG. 22, the light 93' is provided on the outside of the housing 10, similar to the imaging device 92. This light 93' is configured as a so-called bar-shaped light, and is positioned with its longitudinal direction (the direction in which the light-emitting elements are arranged) aligned with the Y direction and its light-emitting surface facing approximately in the +X direction. Like this light 93', it may be oriented in approximately the same direction as the imaging optical axis Ax (approximately the +X direction in the illustrated example) (see optical axis Af in FIG. 22) and illuminate the workpiece obliquely through the first opening 19a. This arrangement allows the lighting fixture to be provided outside the housing 10, improving installation ease. Furthermore, by illuminating the workpiece obliquely through the first opening 19a, specular reflection from the workpiece can be prevented.

Returning to the description of the camera mounting portion 19, the first opening (opening) 19a constituting the camera mounting portion 19 is configured to allow the imaging optical axis Ax of the imaging device 92 and the illumination 93 to pass through. In this case, the camera mounting portion 19 according to this embodiment has the first opening 19a formed in a position opposite the inclined portion 16b, so that the imaging device 92 can be installed so that the imaging optical axis Ax intersects with the mirror surface of the reflecting mirror 71.

The mirror surface of the reflecting mirror 71 is positioned so that the imaging optical axis Ax is bent back toward the surface of the workpiece W. This allows the imaging optical axis Ax to intersect with the surface of the workpiece W, allowing the surface to be imaged.

As shown in FIG. 14, a cover glass 72 may be provided on the underside of the housing 10. In this case, both the laser emission axis Al and the imaging optical axis Ax intersect with the surface of the workpiece W through the cover glass 72. Although not shown in the figure, the cover glass through which the laser emission axis Al passes and the cover glass through which the imaging optical axis Ax passes may be separate.

Also, as shown in Figure 15, the imaging area R3 captured by the imaging device 92 may have a similar shape to the laser light irradiation area R1, and is set to be smaller than the irradiation area R1. Furthermore, the center position of the imaging area R3 is positioned to coincide with the center position Op of the irradiation area R1. Note that Figure 15 illustrates an example in which a general camera is used as the imaging device 92, but if the imaging device 92 is configured using a line scan camera as described above, the imaging area R3 will be a vertically elongated region along the conveying direction At.

Furthermore, when the camera mounting fixture 91 is attached to the camera attachment portion 19 with the imaging device 92 attached to the camera mounting portion 91c, the first opening (aperture) 19a is open to the outside. Therefore, this first opening 19a may be covered with a light-shielding plate, along with the imaging device 92. This light-shielding plate is preferably made of a material such as metal or transparent resin that does not transmit ultraviolet light. For example, if it is covered with transparent resin that does not transmit ultraviolet light, the imaging device 92 may capture images through the transparent resin.

Further Details of Marker Controller 100
The marker controller 100 includes the user terminal 100b described above, as well as a controller main body 100a for controlling the marker head 1. The controller main body 100a includes, as main components, a setting unit 103, a receiving unit 104, a display control unit 105, the first IF unit 106, the second IF unit 107, and the third IF unit 108 described above, the marking control unit 109 also described above, and a trigger monitoring unit 110.

(Setting unit 103)
Based on user input through the operation unit 101, the setting unit 103 sets a printing block that corresponds the character string (printing pattern Pp) to be marked on each work element We by the marking control unit 109 with the attribute information of that printing pattern Pp.

Here, the attribute information of the print pattern Pp includes, for example, one or more of the character font, font size, character thickness, character spacing, and the position of the print pattern Pp as viewed on the setting plane R2.

The various information and parameters set by the setting unit 103 are stored temporarily or continuously in the storage device 120.

In addition, the setting unit 103 can also set information other than character strings, such as the transport speed of the workpiece W and parameters that characterize the timing of marking start, as attribute information (hereinafter also referred to as "job information") for a print job consisting of multiple print blocks.

For example, the setting unit 103 can set, as job information, the offset amount (so-called "trigger delay") from the laser light irradiation area R1 by the laser light scanning unit 3 to the marking start position of the print pattern Pp on each work element We when a specified trigger signal is received. Here, the trigger signal is output each time the mark detection sensor 403 detects the alignment mark Mr.

Therefore, if the waiting time from when the mark detection sensor 403 detects the alignment mark Mr until it starts marking the work element We corresponding to that alignment mark Mr is called the "delay time," then the trigger delay here can be considered to be the amount of movement of the workpiece W during that delay time. By appropriately setting the trigger delay, marking can be performed at more appropriate timing for each workpiece We.

In addition, the setting unit 103 can also set, as job information, whether printing is to be performed while the transport of the workpiece W is temporarily stopped (so-called "static printing"), or whether printing is to be performed while the transport of the workpiece W is continuing without stopping (so-called "moving printing").

The setting unit 103 also accepts a print job selection operation by the user and switches to the selected print job. The setting unit 103 then determines the trajectory that the laser light should follow when marking the character string that makes up each print block of the selected print job. The trajectory that the laser light should follow varies depending on the attribute information described above, such as character thickness and character spacing. The data determined by the setting unit 103 is temporarily or continuously stored in the storage device 120 of the controller main body 100a.

Hereinafter, the data indicating the trajectory that the laser light should follow will be referred to as "expanded data," and the process for determining this expanded data will be referred to as "expanded processing."

(Reception unit 104)
The reception unit 104 receives user input via the operation unit 101 and reflects the input content in the setting items, etc. set by the setting unit 103. The content reflected in the setting items, etc. is overwritten and saved in the storage device 120. For example, the reception unit 104 can receive a change to the character string of a print block when switching print jobs.

(First IF unit 106)
The first IF unit 106 is electrically connected to the PLC 402, and receives a control signal output from the PLC 402 when operating the laser marking system S. This control signal is input to the marking control unit 109 and the like via the first IF unit 106, and is used to control the controller main body 100a.

(Second IF section 107)
The second IF unit 107 is electrically connected to the mark detection sensor 403, and receives a trigger signal indicating that the mark Mr has been detected each time the alignment mark Mr is detected during the transport of the workpiece W.

The trigger signal received by the second IF unit 107 is input to the trigger monitoring unit 110 and the marking control unit 109 via the second IF unit 107. The trigger signal, together with the trigger delay mentioned above, is used to control the timing of marking each work element We.

(Third IF section 108)
The third IF unit 108 is connected to an encoder 401 that outputs a pulse signal (encoder pulse) according to the conveying speed of the workpiece W so as to be able to receive the encoder pulse. The encoder pulse received by the third IF unit 108 is input to the trigger monitoring unit 110, the marking control unit 109, and the setting unit 103 via the third IF unit 108.

(Trigger monitoring unit 110)
The trigger monitoring unit 110 is electrically connected to the second IF unit 107 and the third IF unit 108, and each time the second IF unit 107 receives a trigger signal, it determines whether the movement amount of the work element We corresponding to the trigger signal has reached the offset amount (trigger delay) set by the setting unit 103.

The trigger monitoring unit 110 can make this determination based on, for example, the number of encoder pulses input to the third IF unit 108 after receiving a trigger signal, or the time that has elapsed since receiving a trigger signal. If it determines that the offset amount has been reached after receiving a trigger signal, the trigger monitoring unit 110 inputs a signal indicating this to the marking control unit 109.

When the movement amount of the work element We reaches the offset amount, the housing 10 of the marker head 1 and one work element We corresponding to the trigger signal will be close enough to be marked. Therefore, the trigger monitoring unit 110 of this embodiment exemplifies the "proximity monitoring unit" in this embodiment in that it can detect the proximity of the housing 10 of the marker head 1 and one printing area (i.e., one work element We).

(Marking control unit 109)
The marking control unit 109 reads out the decompressed data stored in advance in the storage device 120, and controls the laser light scanning unit 3 to scan the laser light along the trajectory indicated by the read out decompressed data.

The marking control unit 109 marks each work element We by scanning the surface of each work element We with laser light. As described above, the timing at which marking begins on each work element We can be controlled by a trigger signal and a determination related to the offset amount.

In more detail, when the second IF unit 107 receives a trigger signal, the marking control unit 109 controls the laser light scanning unit 3 based on the determination result by the trigger monitoring unit 110 so that the printing pattern Pp set by the setting unit 103 is marked on the flexible workpiece W.

More specifically, after receiving a trigger signal, the marking control unit 109 is configured to read out the expanded data and control the laser light scanning unit 3 using the expanded data when it determines that the movement amount of the work element We corresponding to that trigger signal has reached the offset amount (trigger delay).

(Display control unit 105)
The display control unit 105 displays a predetermined display screen on the display unit 102 based on various electrical signals, and can also switch the display screen appropriately based on the on/off of a key switch, user input, etc. Furthermore, the display control unit 105 is configured to transition the display mode of each display screen based on the state of the laser marking system S. Details of the display modes will be omitted.

<Example of laser marking system L operation>
Fig. 16 is a flowchart showing the control process performed when operating the laser marking system S, focusing on the processing related to the imaging device 92. Fig. 17 is a time chart illustrating the time series of stationary printing, Fig. 18 is a time chart illustrating the time series of moving printing, and Fig. 19 is a table illustrating the contents of the inspection log.

(moving printing)
In the case of moving printing, in step S1, the marker controller 100 determines whether or not a print trigger signal has been received from the external device 400, such as the PLC 402. If this determination is YES, the control process proceeds to step S2, while if this determination is NO, the determination related to step S1 is repeated. This print trigger signal can be configured to be input from the PLC 402 to the marker controller 100 at a timing slightly delayed from the input timing of an electrical signal (stop signal) input from the PLC 402 to the processing equipment 500 to stop the transportation of the workpiece W by the processing equipment 500, for example.

The top row of Figure 16 illustrates the input period Ts0 of the stop signal. During this period, the transport of the workpiece W is stopped. Also, in the second row of Figure 16, the delay time Ts1 until the print trigger signal is input from the PLC 402 to the marker controller 100 represents the time required for the workpiece W to come to a standstill.

In the following step S2, the trigger monitoring unit 110 determines whether the movement amount of the workpiece W has reached the trigger delay. If the determination is YES, the control process proceeds to step S3, whereas if the determination is NO, the determination related to step S2 is repeated. Note that the determination related to step S2 may also be made based on the elapsed time corresponding to the trigger delay, the number of input pulses, etc.

In the following step S3, the processing equipment 500 as a conveying device receives a detection signal from the trigger monitoring unit 110 as an approach monitoring unit and stops conveying the workpiece W. Then, while the processing equipment 500 is stopping conveying the workpiece W, the laser marking device L performs marking on one workpiece element We (see period Ts2 in Figure 16). Period Ts2 represents the time required for marking.

Then, while transport by the processing equipment 500 is stopped, the imaging device 92 captures an image of a work element We that has been marked by the laser marking device L.

More specifically, in step S4, which follows step S3, the image sensor 404 receives a signal (print completion signal) from the PLC 402 and/or marker controller 100 indicating that marking has been completed. Upon receiving the print completion signal, the image sensor 404 turns on the light 93.

Then, in step S5, which follows step S4, the image sensor 404 determines whether the time elapsed since receiving the print completion signal has reached the predetermined image capture delay Ts3. If the determination is YES, the control process proceeds to step S6, while if the determination is NO, the process related to step S5 is repeated.

By setting the imaging delay Ts3, imaging will be performed a certain amount of time after marking is completed. This prevents smoke generated by marking from appearing in the image. This allows inspection by the image sensor 404 to be performed with high accuracy.

In addition, although there are concerns about heat transfer from the imaging device 92 to the workpiece W, in reality, the workpiece W only spends a short time near the housing 10, so such heat transfer can be minimized as much as possible.

Then, in step S6, which follows step S5, the image sensor 404 inputs an imaging trigger signal to the imaging device 92 and performs imaging of one work element We. Here, as shown in FIG. 16, the timing when marking is performed by the laser marking device L and the timing when imaging is performed by the imaging device 92 fall within the input period Ts0 of the stop signal. In other words, both of these processes are performed while the workpiece W is stopped. After imaging is complete, the image sensor 404 turns off the light 93.

Then, in step S7, which follows step S6, the image sensor 404, which serves as an inspection device, inspects the markings on one work element We after the imaging device 92 has captured the image of that work element We and the processing equipment 500 has resumed transport. As shown in FIG. 16, the timing for the imaging inspection does not fall within the input period Ts0 of the stop signal. Note that inspection by the image sensor 404 may also be performed while transport of the workpiece W is stopped. The period Ts4 in FIG. 16 represents the time required to read the marking contents.

Then, in step S8, which follows step S7, the image sensor 404 determines whether the inspection results were good. If the determination is YES, the image sensor 404 advances the control process to step S9. If the determination is NO, the image sensor 404 advances the control process to step S10.

In step S8, the image sensor 404 also creates an inspection log, as shown in FIG. 19. The first column of this inspection log indicates the identification number (JOB number) assigned to the print job. The second column of the inspection log indicates the cumulative number of marked work elements We. The third column of the inspection log indicates the print content of the print job, as preset by the marker controller 100. The fourth column of the inspection log indicates the OCR results obtained by the image sensor 404. In this case, if the character strings in the third column and the character strings in the fourth column match, the determination in step S8 is YES; if the character strings in the third column and the character strings in the fourth column do not match, the determination in step S8 is NO. The fifth column of the inspection log indicates this determination result. The sixth column of the inspection log indicates the file name of the OCR image. Note that each record (column) of the inspection log may be associated with parameters on the marker controller 100 side (e.g., laser power, scan speed, etc.).

Furthermore, if a barcode, QR code (registered trademark), or the like is used as a marking rather than a character string, the judgment in step S8 may be made based on whether the code was successfully read and whether the read content matches the content set in advance. Alternatively, it may be determined whether marking has been applied (whether there are traces of marking on the surface of the workpiece W). Furthermore, these judgments may be combined, for example, using an OR condition.

In the following step S9, the image sensor 404 stores the OCR image in various storage devices and then returns. Meanwhile, in step S10, the image sensor 404 stores the OCR image in various storage devices, as in step S9, and then returns. In the latter case, the image sensor 404 may stop operation of the entire laser marking system L via the PLC 402, etc.

The flow shown in Figure 16 is based on the assumption that the marking content will be inspected after marking, but the surface condition of the workpiece W may also be inspected before marking. In this case, inspection items include, for example, defect inspection to monitor whether or not there are holes on the surface of the workpiece W, inspection related to the alignment of the workpiece W, and foreign matter inspection to monitor whether or not there are foreign matters on the surface of the workpiece W.

(moving printing)
In the case of moving printing, in step S1, the marker controller 100 determines whether or not a trigger signal has been received (whether or not the alignment mark Mr has been detected) from the mark detection sensor 403. If this determination is YES, the control process proceeds to step S2, whereas if this determination is NO, the determination related to step S1 is repeated.

The top row of Figure 17 shows an example of a pulse indicating that a trigger signal has been received. Regardless of whether or not this trigger signal has been received, the transport of the workpiece W will continue.

In the following step S2, the trigger monitoring unit 110 determines whether the movement amount of the workpiece W has reached the trigger delay. If the determination is YES, the control process proceeds to step S3, whereas if the determination is NO, the determination related to step S2 is repeated. Note that the determination related to step S2 may also be made based on the elapsed time corresponding to the trigger delay, the number of input pulses, etc.

Furthermore, the period Td2 in the second row of Figure 17 indicates the elapsed time until the movement amount of the workpiece W reaches the trigger delay.

In the following step S3, the laser marking device L performs marking on one work element We being transported by the processing equipment 500. Here, the period Td2 in Figure 17, like the period Ts2 in Figure 16, refers to the time required for marking.

The imaging device 92 is configured to capture an image of a work element We within the period Td0 from when the laser marking device L performs marking on the work element We until the trigger monitoring unit 110 receives a detection signal regarding another work element We that is transported following the work element We.

More specifically, in step S4, which follows step S3, the image sensor 404 receives a signal (print completion signal) from the PLC 402 and/or marker controller 100 indicating that marking has been completed. Upon receiving the print completion signal, the image sensor 404 turns on the light 93.

Then, in step S5, which follows step S4, the image sensor 404 determines whether the time elapsed since receiving the print completion signal has reached a predetermined imaging delay Td3. If the determination is YES, the control process proceeds to step S6, while if the determination is NO, the process related to step S5 is repeated.

Then, in step S6, which follows step S5, the image sensor 404 inputs an imaging trigger signal to the imaging device 92 and performs imaging of one work element We. After imaging is complete, the image sensor 404 turns off the light 93.

Then, in step S7, which follows step S6, the image sensor 404, acting as an inspection device, inspects the marking on one work element We within the period Td0 from when the imaging device 92 performs marking on the former work element We until the trigger monitoring unit 110 receives a detection signal for the other work element We.

From this point on, the details of the inspection process are the same as in the static printing case, so we will omit the explanation.

<Layout of the imaging optical axis Ax>
As described above, according to this embodiment, by laying out the imaging optical axis Ax so that it passes through the internal space (optical path partition H3) between the pair of extensions H21, H22, it is possible to extend the imaging optical axis Ax from the imaging device 92 to the surface of the workpiece W even when the distance between the housing 10 and the workpiece W is very short (see, for example, FIG. 14 ). This makes it possible to fit a wider range into the imaging field of view, improving the usability of the laser marking device L.

Furthermore, as shown in Figure 3, if the housing 10 is suspended from above, the distance between the housing 10 and the workpiece W may be shorter than if it is supported from the side, below, etc. The configuration disclosed herein can ensure a wider imaging field even when such a layout is adopted, and is advantageous in improving the usability of the laser marking device L.

Furthermore, as shown in Figures 10 and 11, at least one of the pair of extension portions H21, H22 (in this embodiment, both) can be used as storage space for the heat sinks 81, 82. This makes it possible to effectively utilize the internal space of the pair of extension portions H21, H22 without it becoming dead space.

Furthermore, as explained using Figure 14, by configuring the inclined portion 16b, which serves as a wall portion, to be able to mount a reflecting mirror 71, it becomes possible to bend the imaging optical axis Ax using the reflecting mirror 71. This makes it possible to adopt a wider variety of layouts when arranging the imaging optical axis Ax so that it passes through the optical path partition portion H3. Increasing the degree of freedom in the layout of the imaging optical axis Ax contributes to improving the usability of the laser marking device L.

Furthermore, as explained using Figure 14, the reflection mirror 71 makes it possible to guide the imaging optical axis Ax to the surface of the workpiece W. This allows the laser light irradiation area R1 set on the surface of the workpiece W to coincide with or be close to the imaging field of view (imaging area R3) of the imaging device 92, as shown in Figure 15. This makes it possible to image the workpiece W, for example, immediately after or immediately before marking, which is advantageous in improving the usability of the laser marking device L.

Furthermore, as explained using Figures 14 and 15, it is possible to lay out the lighting 93 within the optical path partition H3. This improves the quality of the captured image, such as visibility, and is therefore advantageous in improving the usability of the laser marking device L.

Furthermore, as explained using Figures 14 and 15, the imaging optical axis Ax and the direction in which the illumination light is emitted differ, making it possible to suppress halation and other problems caused by specular reflection of the illumination light. This improves the quality of the captured image, and is further advantageous in improving the usability of the laser marking device L.

Other Embodiments
Although the imaging device 92 according to the embodiment is configured to be attached to the outer surface (front surface 10f) of the housing 10, the present disclosure is not limited to such a configuration. For example, the imaging device 92 may be laid out inside the housing 10.

Here, Figure 20 is a diagram corresponding to Figure 11 showing a first modified example of the laser marking device, and Figure 21 is a diagram corresponding to Figure 12 showing a second modified example of the laser marking device.

In the case of the marker head 1' according to the first modified example, the camera mounting section is composed of the first casing 50 and a through-hole provided in its bottom surface. In this case, the imaging device 92 is mounted within the housing 10 and housed in the mirror housing section H11, similar to the first mirror 31a. The imaging optical axis Ax of the imaging device 92 extends at an angle toward the +Z side, passing sequentially through the cover glass 42 and the optical path partition section H3, which serves as the internal space.

On the other hand, in the case of the marker head 1" according to the second modified example, the camera mounting portion is configured in the space between the defocus lens 37 and the cover glass 42. In this case, the imaging device 92 is mounted inside the housing 10 and housed in the space between the defocus lens 37 and the cover glass 42. The imaging optical axis Ax of the imaging device 92 extends at an angle toward the +Z side, just like the laser marking device 1' according to the first modified example, and passes in turn through the cover glass 42 and the optical path partition section H3, which serves as the internal space.

When the imaging device 92 is housed within the housing 10 as in the first and second variants, it is preferable that the imaging device 92 be configured as a so-called wide-angle camera having a wide-angle lens.

In addition, in this embodiment, the imaging device 92 is located outside the housing 10. However, for example, a dust collector (vacuum cleaner) may be located instead of the imaging device 92. That is, the first opening 19a may be configured so that the tip of the dust collector's hose can be attached. This allows the fumes (smoke) generated during film printing to be sucked in, allowing the imaging device 92 to capture a clearer image of the printing result (an image that does not include smoke).

Furthermore, the cover glass 42 attached to the housing 10 may become contaminated by the fumes mentioned above. If the cover glass 42 becomes contaminated, this may lead to a decrease in laser output, which may have a negative impact on print quality. Therefore, a cleaning tool with a rubber roller attached to the tip of a long, thin handle may be provided. This cleaning tool can be inserted through the first opening 19a to wipe off dirt adhering to the cover glass 42.

If a strong force is applied to the cover glass 42 when wiping it with a cleaning tool, there is a risk that the cover glass 42 may be damaged (e.g., broken). Therefore, a guide groove (guide rail) may be provided on the inner wall of the housing 10, and the cleaning tool may be moved back and forth (inserted and removed) from the front along the guide groove. This prevents unnecessary force from being applied to the cover glass 42.

S Laser marking system L Laser marking device 1 Marker head 2 Laser light generating unit 3 Laser light scanning unit 4 Exit window 42 Cover glass (optical member)
10 Housing 10u Top surface 10d Bottom surface 16b Inclined portion (wall portion)
16c Inclined surface (mirror mounting part)
19 Camera mounting portion 71 Reflecting mirror 81 First heat sink 82 Second heat sink 9 Camera unit 91 Camera mounting fixture 91d Lighting mounting portion 92 Imaging device 93 Lighting 100 Marker controller 100a Controller main body 100b User terminal 110 Trigger monitoring unit (approach monitoring unit)
404 Image sensor (inspection device)
500 Processing equipment (transportation equipment)
At: conveying direction Al; laser emission axis Ax: imaging optical axis H1: first storage section (storage section)
H21 Crystal-side accommodation section (first extension section)
H22 Light source side housing section (second extension section)
H3 Optical path partition (internal space)
W Work We Work element (printed area)

Claims (16)

a laser light generating unit that generates a laser light;
a laser beam scanning unit that reflects the laser beam generated by the laser beam generating unit to scan the laser beam on a surface of a workpiece;
a housing that houses the laser light generating unit and the laser light scanning unit,
The housing includes:
a housing portion provided with an optical member that transmits the laser light reflected by the laser light scanning portion;
a pair of extension portions extending from the housing portion along an emission direction of the laser light so as to sandwich an optical axis of the laser light transmitted through the optical member;
a camera mounting portion to which an imaging device can be mounted so that an imaging optical axis passes through an internal space formed by the pair of extension portions ,
Each of the pair of extending portions has a partition member that defines the internal space and forms an accommodation space for accommodating a component inside the extending portion.
A laser marking device characterized by: 2. The laser marking device according to claim 1,
the housing has a bottom surface on which the optical member is provided and a top surface opposite the bottom surface,
The laser marking device is characterized in that the housing is configured to be suspended via the top surface. 3. The laser marking device according to claim 1,
A laser marking device characterized in that a heat sink thermally coupled to a laser light generating unit is accommodated in at least one of the storage spaces partitioned inside the pair of extension portions. 4. The laser marking device according to claim 1,
The pair of extension portions are
a first extension portion disposed on one side in a first direction with respect to an optical axis of the laser light;
a second extending portion disposed on the other side in the first direction across the optical axis of the laser light and spaced apart from the first extending portion;
The housing includes:
a wall portion connecting the first and second extension portions and dividing the internal space;
a mirror mounting portion provided on the wall portion and configured to be able to mount a reflecting mirror;
The laser marking device is characterized in that the camera mounting portion is configured to allow the imaging optical axis to pass through an opening formed in a position opposite the wall portion, and to install the imaging device so that the imaging optical axis intersects with the mirror surface of the reflecting mirror. 5. The laser marking device according to claim 4,
The reflecting mirror is attached to the mirror attachment portion,
A laser marking device characterized in that the mirror surface of the reflecting mirror is arranged so as to bend the imaging optical axis toward the surface of the workpiece. 6. The laser marking device according to claim 1,
A laser marking device comprising a lighting mounting portion disposed in the internal space and configured to be able to mount lighting. 7. The laser marking device according to claim 6,
The lighting fixture is attached to the lighting fixture attachment portion,
A laser marking device, characterized in that the illumination is arranged so as to be oriented in a direction intersecting the imaging optical axis. 8. The laser marking device according to claim 1,
the imaging device is mounted within the housing;
The laser marking device is characterized in that the imaging device is configured as a wide-angle camera having a wide-angle lens. A laser marking device according to any one of claims 1 to 8;
a conveying device that conveys the workpiece along a predetermined conveying direction,
A plurality of printable areas are set on the surface of the workpiece at equal intervals along the transport direction,
A laser marking system configured such that the laser marking device sequentially performs marking on each of the marking areas conveyed by the conveying device,
an approach monitoring unit that detects approach between the housing and one printing area;
the transport device stops transporting upon receiving a detection signal from the approach monitoring unit;
the laser marking device performs marking on the one print area while the conveying device is halting conveyance;
The laser marking system is characterized in that the imaging device performs imaging of the one printing area on which marking has been performed by the laser marking device while transportation by the transport device is stopped. 10. The laser marking system according to claim 9,
an inspection device that inspects the marking content by the laser marking device based on the imaging result by the imaging device;
A laser marking system characterized in that the inspection device inspects the marking on the one printing area after the imaging device has performed an image of the one printing area and the conveying device has resumed conveying. A laser marking device according to any one of claims 1 to 8;
a conveying device that conveys the workpiece along a predetermined conveying direction,
A plurality of printable areas are set on the surface of the workpiece at equal intervals along the transport direction,
A laser marking system configured such that the laser marking device sequentially performs marking on each of the marking areas conveyed by the conveying device,
an approach monitoring unit that detects approach between the housing and one printing area;
the laser marking device performs marking on the one print area being transported by the transport device every time the laser marking device receives a detection signal from the approach monitoring unit ;
A laser marking system characterized in that the imaging device performs an image of the one printing area within the period from when the laser marking device performs marking on the one printing area to when the approach monitoring unit outputs a detection signal for another printing area that is transported following the one printing area. 12. The laser marking system according to claim 11,
The laser marking system is characterized in that the imaging device is configured by a line scan camera having an imaging field of view extending along a conveying width direction perpendicular to the conveying direction. 13. The laser marking system according to claim 11 or 12,
an inspection device that inspects the marking content made by the laser marking device based on the imaging result of the imaging device;
A laser marking system characterized in that the inspection device inspects the marking on one printable area within the period from when the laser marking device performs marking on the one printable area to when the approach monitoring unit outputs a detection signal for the other printable area. a laser light generating unit that generates a laser light;
a laser beam scanning unit that reflects the laser beam generated by the laser beam generating unit to scan the laser beam on a surface of a workpiece;
a housing that houses the laser light generating unit and the laser light scanning unit,
The housing includes:
a housing portion provided with an optical member that transmits the laser light reflected by the laser light scanning portion;
a pair of extension portions extending from the housing portion along an emission direction of the laser light so as to sandwich an optical axis of the laser light transmitted through the optical member;
a camera mounting portion to which an imaging device can be mounted so that an imaging optical axis passes through an internal space formed by the pair of extension portions,
At least one of the pair of extension portions accommodates a heat sink thermally coupled to the laser light generating portion.
A laser marking device characterized by: a laser light generating unit that generates a laser light;
a laser beam scanning unit that reflects the laser beam generated by the laser beam generating unit to scan the laser beam on a surface of a workpiece;
a housing that houses the laser light generating unit and the laser light scanning unit,
The housing includes:
a housing portion provided with an optical member that transmits the laser light reflected by the laser light scanning portion;
a pair of extension portions extending from the housing portion along an emission direction of the laser light so as to sandwich an optical axis of the laser light transmitted through the optical member;
a camera mounting portion to which an imaging device can be mounted so that an imaging optical axis passes through an internal space formed by the pair of extension portions,
The pair of extension portions are
a first extension portion disposed on one side in a first direction with respect to an optical axis of the laser light;
a second extending portion disposed on the other side in the first direction across the optical axis of the laser light and spaced apart from the first extending portion;
The housing includes:
a wall portion connecting the first and second extension portions and dividing the internal space;
a mirror mounting portion provided on the wall portion and configured to be able to mount a reflecting mirror;
The camera mounting section is configured to have the imaging device installed so that the imaging optical axis passes through an opening formed in a position facing the wall section and intersects with the mirror surface of the reflecting mirror.
A laser marking device characterized by: a laser marking device comprising: a laser light generating unit that generates laser light; a laser light scanning unit that reflects the laser light generated by the laser light generating unit to scan the laser light on a surface of a workpiece; and a housing that houses the laser light generating unit and the laser light scanning unit, wherein the housing has: a housing portion in which an optical member that transmits the laser light reflected by the laser light scanning unit is provided; a pair of extension portions that extend from the housing portion along the emission direction of the laser light so as to sandwich the optical axis of the laser light that has transmitted through the optical member; and a camera mounting portion on which an imaging device can be mounted so that an imaging optical axis passes through an internal space formed by the pair of extension portions;
a conveying device that conveys the workpiece along a predetermined conveying direction,
A plurality of printable areas are set on the surface of the workpiece at equal intervals along the transport direction,
A laser marking system configured such that the laser marking device sequentially performs marking on each of the marking areas conveyed by the conveying device,
an approach monitoring unit that detects approach between the housing and one printing area;
the transport device stops transporting upon receiving a detection signal from the approach monitoring unit;
the laser marking device performs marking on the one print area while the conveying device is halting conveyance;
The imaging device captures an image of the one printing area on which marking has been performed by the laser marking device while the conveyance device is stopped.
A laser marking system characterized by: