JP7565014B2 - Image forming apparatus, image forming apparatus main body, system for image forming apparatus and installation parts - Google Patents

Description

The present invention relates to an image forming device, an image forming device main body, a system for an image forming device, and installation parts.

2. Description of the Related Art Conventionally, there has been known an image forming apparatus that includes a recording unit that records an image on a recording medium and a housing for the apparatus that houses the recording unit.
For example, Japanese Patent Application Laid-Open No. 2003-233662 describes a portable image forming apparatus that forms an image on a recording material by moving the image forming apparatus main body in a scanning direction so as to rotate a rotatable roller in contact with the surface of the recording material (recording medium). It is said that the use of the rotatable roller provides straight running performance.

In addition to straight-line running ability, it is desirable to be able to suppress image distortion when forming an image on a recording medium with an uneven surface.

In order to solve the above-mentioned problems, the present invention provides an image forming device having a recording unit that records an image on the side facing a recording medium and a rotatable roller, characterized in that the device is provided with a contact portion that is arranged to contact the recording medium at at least three points, a holding means that holds the roller so that it can move back and forth between a position where it protrudes toward the recording medium side from the contact portion and a position where it does not protrude toward the recording medium side from the contact portion, and a biasing means that biases the roller toward the protruding position.

The present invention makes it possible to suppress image distortion when forming an image on a recording medium that has a straight-line running property and an uneven surface, compared to conventional methods.

Schematic diagram for explaining the operation of the HMP1 of the present embodiment. FIG. FIG. 4 is a schematic cross-sectional view of the HMP as viewed from the left side. FIG. 4 is a schematic top view showing the positional relationship between the HMP and a print image on a recording paper. FIG. 2 is a block diagram showing a part of the electrical circuit of the HMP. FIG. 2 is an external perspective view of the HMP as viewed obliquely from below. FIG. 2 is an external perspective view of the HMP as viewed obliquely from below. FIG. 6A to 6C are explanatory diagrams illustrating the sliding movement of the claw members of the print medium contact unit. 5 is an explanatory diagram of a movable engagement portion of the print medium contact unit. FIG. FIG. 4 is an explanatory diagram of a head cover member of the HMP. FIG. 2 is an explanatory diagram of an HMP1 equipped with a roller-advancing/retracting type print medium contact unit according to the present embodiment. 13 is a cross-sectional view taken along line B-B of FIG. 12 . A cross-sectional view taken along the line CC in FIG. FIG. 13 is an explanatory diagram of the operation of HMP1 in FIG. 12 . FIG. 13 is an explanatory diagram of a modified example of HMP1 in FIG. 12. FIG. 11 is an explanatory diagram of another example of the print medium contact unit.

The following describes an embodiment in which the present invention is applied to a handy mobile inkjet printer (hereinafter referred to as HMP), which is a portable image forming device. First, the basic configuration of the device body of the HMP according to the embodiment will be described.

2 is a perspective view of the HMP1 according to the embodiment. The housing of the HMP1 is mainly composed of an upper unit 2 and a lower unit 3. The upper unit 2 is supported by the lower unit 3 so as to open and close relative to the lower unit 3. The illustrated state shows a state in which the upper unit 2 has been rotated counterclockwise from the state shown in FIG. 3 with respect to the lower unit 3 about the upper unit rotation shaft 3a as a fulcrum so that an operator can access the inside of the lower unit 3 (open state relative to the lower unit 3). An ink cartridge 40 is housed inside the lower unit 3 as a recording unit or a removable unit. FIG. 2 also shows the removed ink cartridge 40. This ink cartridge 40 is integrally equipped with an inkjet head 41 and an ink tank. The ink tank contains ink, which is a recording material. The ink cartridge 40 is mounted so that the inkjet head 41, which ejects droplets of ink, which is an image forming material, faces vertically downward. This inkjet head 41 ejects droplets of ink from an ejection port (nozzle) to record an image, thereby forming an image. The ink tank contains ink.

When the upper unit 2 is closed relative to the lower unit 3, the HMP1 has a generally rectangular parallelepiped shape. The inkjet head 41 is exposed on the underside of the main body (image forming device main body) of the HMP1. The left-right direction (short side direction) on this underside is the X-axis direction, and the longitudinal direction of the main body perpendicular to the X-axis direction on the underside is the Y-axis direction. The length of the short side direction (X-axis direction) is long enough for a user to hold it in the palm of their hand.

The HMP1 is equipped with a print medium contact unit 100, which is an installation part that is integral with the lower unit 3, which is part of the main body of the housing, and is detachable. The print medium contact unit 100 has a portion that contacts the recording medium in the HMP1 at at least three points. This will be described in detail later. The side of the lower unit 3 shown in FIG. 2 is the left side 32, and the surface of the upper unit 2 that constitutes the side of the housing when the upper unit 2 is closed is the front 35. As shown in FIG. 1, the side opposite the left side 32, which is the side of the lower unit 3, is the right side 33, and the surface of the lower unit 3 that opposites the front 35, which is the surface of the upper unit 2 that constitutes the side of the housing when the upper unit 2 is closed, is the back 34.

Figure 3 is a schematic cross-sectional view of the HMP1 as viewed from the left side (left side surface 32 side). As shown in Figure 3, the upper unit 2 is L-shaped with a horizontal extension portion 2a extending in the Y-axis direction and a vertical extension portion 2b extending in the Z-axis direction. Inside the vertical extension portion 2b of the upper unit 2, a battery 15 is disposed, which is a power source for supplying power to each device of the HMP1. A control board 14 is disposed in the horizontal extension portion 2a. A print button 5a and a power button 5b are connected to the control board 14.

The lower unit 3 is provided with an upper unit rotating shaft 3a on the rear surface 34 side that rotatably supports the upper unit 2. It also has an FPC contact portion 13 as a connection portion with the ink cartridge 40. The FPC contact portion 13 is electrically connected to a control board 14 in the upper unit 2 via a flexible flat cable 25. It also has a position detection sensor 18, an upper unit locking claw 11, etc. The interior of the lower unit 3 is a storage space for the ink cartridge 40. By rotating the upper unit 2 relative to the lower unit 3 in the direction of arrow "B" in Figure 3, with the upper unit rotating shaft 3a as a fulcrum, an opening at the top of the internal space of the lower unit 3 is exposed, and the ink cartridge 40 placed inside the housing 80 can be removed.

The position detection sensor 18 is a sensor that detects the distance to the surface of the recording material, the surface condition (e.g. unevenness), and the movement distance of the HMP1. The position detection sensor 18 shines light onto the location (recording material) where it is placed, and reads the condition of that area as a "pattern." The amount of movement is then calculated by continuously capturing how the "pattern" moves in response to the movement of the position detection sensor 18.

Figure 4 is a schematic top view showing the positional relationship between the HMP1 and the print image on the recording paper P as a recording medium. The illustrated recording paper P is, for example, A4 size. The HMP1 shown by the dashed line in Figure 4 indicates the position before moving in the scanning direction, and the HMP1 shown by the solid line in Figure 4 indicates the position after moving in the scanning direction. When the user presses the print button 5a once and then moves the HMP1 in the scanning direction, the HMP1 main body moves in the scanning direction and ink is ejected from each of the multiple ejection holes in the printing area corresponding to the width of the row of ejection holes, and is printed (recorded) on the recording paper P as a recording medium. When the HMP1 is moved from the position before the movement shown by the dashed line in Figure 4 to the position after the movement shown by the solid line in Figure 4, images are formed in the order of "A", "B", "C", "D", "E", and "F" in Figure 4. The print operation using the HMP1 is not limited to the above-mentioned operation.

FIG. 5 is a block diagram showing a portion of the electrical circuit of the HMP1.
The control board 14 has a CPU 155 that performs various calculation processes and executes programs, a Bt (Bluetooth (registered trademark)) board 152 for short-range wireless communication, a RAM 153 that temporarily stores data, a ROM 154, a recording control unit 156, and the like.

The Bt board 52 communicates data with external devices such as smartphones and tablet terminals via short-range wireless communication (Bluetooth (registered trademark) communication). The ROM 154 stores firmware that controls the hardware of the HMP1, drive waveform data for the inkjet head, and the like. The recording control unit 156 processes data to drive the inkjet head and generates drive waveforms.

The control board 14 is electrically connected to a gyro sensor 157, a position detection sensor 18, a capping sensor 158, an LED lamp 5c, an inkjet head 41, a print button 5a, a power button 5b, a battery 15, etc. A USB connection port 15a is connected to the battery 15.

The gyro sensor 157 detects the inclination and rotation angle of the HMP1 using well-known technology and transmits the results to the control board 14. The LED lamp 14a is provided inside the exterior cover of the print button 5a, which is made of a light-transmitting material, and causes the print button 5a to emit light.

When the power button 5b is pressed to turn on the HMP1, power is supplied to each module, and the CPU 155 begins startup operations based on the programs stored in the ROM 154, and loads the programs and each data into the RAM 153. When image data is received from an external device via communication such as short-range wireless communication, the recording control unit 156 generates a drive waveform according to the received image data. Then, it controls the ejection of ink from the inkjet head so as to form an image according to the position on the surface of the recording material detected by the position detection sensor 18. This recording control unit 156 corresponds to the drive control means that controls the drive of the recording unit based on the detection results of the position detection means.

When the control board 14 is acquiring image data through short-distance wireless communication with an external device, it causes the LED lamp 14a to flash, thereby causing the light-transmitting print button 5a to flash and emit light. After that, when the control board 14 has completed acquiring the image data, it causes the LED lamp 14a to light continuously, thereby causing the print button 5a to emit light continuously. Seeing this, the user knows that the HMP1 has finished acquiring the image data, and places the HMP1 on the recording material and presses the print button 5a.

Meanwhile, when the control board 14 starts controlling the continuous lighting of the LED lamp 14a, it waits for the print button 5a to be pressed. Then, when the print button 5a is pressed, the LED lamp 14a is made to flash, causing the print button 5a to flash with light. Seeing this, the user starts moving the HMP1 in the direction perpendicular to the scanning direction (manual scanning).

After completing the movement operation (manual scanning) of the HMP1, the user presses the print button 5a again. This causes the control board 14 to turn off the LED lamp 14a and stop the emission of light from the print button 5a. Furthermore, if the HMP1 is picked up from the recording material and placed on a table or the like without pressing the print button 5a, the position detection sensor 18 will not be able to detect the position when the HMP1 is picked up from the recording material. Therefore, the control board 14 turns off the LED lamp 14a and stops the emission of light from the print button 5a at the timing when the position detection sensor 18 no longer detects the position.

It is not necessary to keep pressing the print button 5a during the movement operation (manual scanning). If the print button 5a is pressed and released prior to the movement operation, the image formation process based on the detection result by the position detection sensor 18 will continue until the next timing. In other words, it will continue until the end of image formation, until the print button 5a is pressed again, or until the position detection sensor 18 is unable to detect the position or detects that it has moved away from the recording material by more than a predetermined distance.

The recording medium is not limited to paper such as recording paper P, but includes any medium on which recording can be performed, such as overhead projectors, cloth, cardboard, packaging containers, glass, and substrates. A known configuration can be applied to the so-called inkjet mechanism that performs recording by ejecting liquid or droplets such as ink from the ink cartridge 40. In addition, any inkjet mechanism that can be mounted on the HMP1 can be used as appropriate.

The area that can be printed simultaneously by the inkjet head 41 corresponds to the area where the ejection holes are formed, and the ink (liquid) ejected from the ejection holes is not particularly limited as long as it has a viscosity and surface tension that allows it to be ejected from the ejection holes. However, it is preferable that the viscosity of the ink (liquid) is 30 mPa·s or less at room temperature and normal pressure, or by heating or cooling. In detail, the ink (liquid) is a solution, suspension, emulsion, etc. that contains a solvent such as water or an organic solvent, a colorant such as a dye or a pigment, a functionalizing material such as a polymerizable compound, a resin, a surfactant, a biocompatible material such as DNA, amino acids, proteins, calcium, an edible material such as a natural dye, etc. These can be used for applications such as inkjet ink, surface treatment liquid, a liquid for forming a resist pattern of a component of an electronic element or a light-emitting element, a material liquid for three-dimensional modeling, etc.

The print medium contact unit 100 in this embodiment achieves both straight-line and curved running properties by switching the print medium contact unit 100 used, and also reduces physical constraints compared to conventional methods.

The portable image forming device described in Figures 15 and 17 of Patent Document 1 uses a detachable spacer member (e.g., spacer member 75) for the portable image forming device body. This spacer member has multiple protrusions (protrusions 76) for point-supporting the portable image forming device body. When attached to the portable image forming device body, the spacer member is interposed between the portable image forming device body and the surface of the recording material, and the roller for ensuring straightness is lifted from the surface of the recording material. This improves curvature. By attaching and detaching such a spacer member, both straight-line running ability and curved running ability are achieved.

However, the specific example of how the spacer member in Patent Document 1 can be made detachable uses magnets, and there is a need to improve the stability of maintaining the attached state. Furthermore, not only is it necessary to achieve both straight-line and curved running properties, but when printing on a different print medium, a contact portion configuration that is suitable for that print medium is required. As in Patent Document 1, there are many physical constraints when adding a new contact portion configuration such as a spacer member to the contact portion configuration of the rollers that are already installed, and there are limits to the contact portion configurations that can be supported.

In this embodiment, the print medium contact unit 100, which is the part that contacts the recording medium at at least three points, is configured as an installation part that is integral with the main body of the housing and can be attached and detached, and the print medium contact unit 100 is attached to the main body of the housing by mechanical engagement. The part that contacts at least three points defines a plane at these points, and at least one of the points is located outside the straight line connecting the other two points.

Figure 6 is an external perspective view of the HMP1 of this embodiment, seen from diagonally below. This figure shows the state in which the ink cartridge 40 is not set. The illustrated state also shows the print medium contact unit 100 separated from the main body (lower unit 3) of the housing of the HMP1. A position detection sensor 18 is located on the lower surface (bottom surface) 30 of the lower unit 3. An opening 30a is also formed to expose the inkjet head 41. A hook plate portion 210 with a hook hole 210a formed therein is provided in the approximate center in the X-axis direction on the rear surface 34 side of the lower surface 30. A hook plate portion 220 with a hook hole 220a formed on each end side in the X-axis direction is provided on the front surface 35 (see Figure 3) side of the lower surface 30.

The print medium contact unit 100 is a plate-shaped base member 100a that holds four rollers 37a, 37b, 38a, 38b whose rotation axes are parallel to each other to ensure straightness. These rollers can rotate about their parallel rotation axes. These rollers correspond to the parts that come into contact with the recording medium. The base member 100a is formed with an opening 100b for exposing the detection parts such as the optical sensor of the position detection sensor 18, and an opening 100c for exposing the inkjet head 41. The base member 100a is also provided with hooks 110, 120, 120 that enter into the hook holes 210a, 220a of the lower unit 3 to perform hooking engagement as a mechanical engagement.

Figure 7 is an external perspective view of the HMP1, seen from diagonally below, with the print medium contact unit 100 attached to the lower unit 3 by hooking and engaging it. The reference numeral 300 in Figures 6 and 7 denotes the attachment portion of the head cover member 310 (see Figure 11), which will be described later.

8 is an enlarged perspective view of the print medium contact unit 100, where (a) is a view from the lower surface (bottom surface) side and (b) is a view from the upper surface side (the side facing the lower unit 3 when attached to the lower unit 3). As shown in FIG. 8(a), the four rollers 37a, 37b, 38a, and 38b are held by the base member 100a as follows. That is, the left first roller 37a and the left second roller 37b are fixed to the left rotating shaft 37c, and the left rotating shaft 37c is held rotatably relative to the base member 100a. Similarly, the right first roller 38a and the right second roller 38b are fixed to the right rotating shaft 38c, and the right rotating shaft 38c is held rotatably relative to the base member 100a. The left rotating shaft 37c and the right rotating shaft 38c are configured to extend in the Y-axis direction and be parallel to each other when the print medium contact unit 100 is attached to the lower unit 3.

As shown in FIG. 8(a), the hook portion 110 on the side (back side) located on the back side 34 shown in FIG. 7 has a vertical portion 110a extending vertically upward (Z-axis direction) from the base member 100a, and a horizontal portion 110b extending horizontally (-Y-axis direction) from its tip toward the back side 34. The horizontal portion 110b fits into and engages with the hook hole 210a on the lower unit 3 side.

The left and right hook portions 120 on the side located on the front surface 35 side (front surface side) shown in FIG. 3 have a symmetrical structure. As shown by the reference numerals attached to the right hook portion 120 in FIG. 8(a), an operation portion 121 for releasing the lock is provided. The base member 100a has a side wall portion 130 extending upward to guide the sliding of the operation portion 121 in the horizontal direction (±Y axis direction). A guide hole 130a extending horizontally is formed in the side wall portion 130. A shaft portion 121a that passes through the guide hole 130a is attached integrally to the operation portion 121.

As shown in FIG. 8(b), a retaining member 123 for fixing the claw member 124 to the shaft portion 121a is fixed to the tip portion of the shaft portion 121a that penetrates the side wall portion 130. The claw member 124 is fixed to this shaft portion 121a so as to slide together with the operation portion 121. The claw member 124 is integrally formed with a claw portion 124a that enters and engages with the hook hole 220a (see FIG. 6) on the lower unit 3 side. A storage portion 132 for a compression spring for biasing is also formed at a location of the base member 100a facing the claw member 124. The claw member 124 corresponds to the movably provided engagement portion. The operation portion 121 corresponds to the operation portion provided on the side portion (outer side wall portion) that intersects with the surface that exposes the recording portion among the multiple surfaces around the main body of the housing.

9 is an explanatory diagram of the sliding movement of the claw member 124, where (a) shows the state where it has slid to the most front side (Y-axis direction), and (b) shows the state where it has slid to the most rear side (-Y-axis direction) by the movement of arrow A7. As shown in FIG. 9(a), a compression spring 125 is housed in the housing portion 132, and the claw member 124 is biased to the front side, which is the right side in the figure. The tip of the claw portion 124a abuts against the inner surface of the front side side wall portion 131, which is formed to rise upward (Z-axis direction) from the upper surface of the base member 100a. Normally, it is in this abutting state. When the print medium contact unit 100 is attached to the lower unit 3, the claw portion 124a enters the engagement hole on the lower unit 3 side in this state and is in an engaged state. The compression spring 125 corresponds to a biasing means that biases the movable engagement portion to an engagement position where it engages.

As shown by arrow A7 in Figure 9(b), when the operating part 121 is operated against the compression spring 125 to slide the claw member 124 to the rearmost position, the claw member 124a comes completely out of the hook hole 220a (see Figure 6) on the lower unit 3 side. In other words, by shifting (moving) this operating part 121, the claw member 124 of the hook part 120 shifts, and the hook (engagement) with the lower unit 3 is released. The engagement is released when the claw member 124 comes out of the hook hole 220a on the lower unit 3 side.

Figure 10 is an explanatory diagram of the movable hook portion 120 when the print medium contact unit 100 is attached to the lower unit 3 (when the print medium contact unit 100 is pressed against the lower unit 3). Figure 10(a) is an explanatory diagram of the cross-sectional position of the X-X cross section, and Figures 10(b) to (d) are views of the X-X cross section in Figure 10(a) as viewed from the direction of arrow A. The attachment proceeds in the order of Figures 10(b), (c), and (d). In the state of Figure 10(b), the claw member 124 is positioned in the state of Figure 9(a) by the compression spring 125. As shown in an enlarged view of the claw portion 124a of the claw member 124 on the right side of (b), the claw portion 124a has a tapered portion 124b that abuts against the tip portion 220b of the hook plate portion 220 on the lower unit 3 side. The attachment proceeds from Figure 10(b) to (c) as the print medium contact unit 100 is pushed into the lower unit 3 side. During this time, the contact force that the tapered portion 124b receives from the tip portion 220b causes the claw member 124 to slide (move) to the left in the figure against the compression spring 125.

Then, as shown in Figure 10(c), the tip of the claw portion 124a comes into contact with the inner side surface 220c of the hook plate portion 220. When the installation proceeds further from this Figure 10(c), as shown in Figure 10(d), the claw portion 124a faces the hook hole 220a of the hook plate portion 220, and is pushed into the hook hole 220a by the biasing force of the compression spring 125, completing the engagement. At this point, the claw member 124 is in the state shown in Figure 9(a).

Instead of making the print medium contact unit 100 movable, the lower unit 3 can be made movable, or both can be made movable. Instead of the front side, the rear side, which is fixed, can be made movable, or both can be made movable.

Figure 10(a) shows the head cover member 310 attached to the main body (lower unit 3) of the housing of the HMP1. The head cover member 310 is rotatably attached by a rotation shaft 301 that is held at both ends by an attachment part 300 (see Figure 6) of the lower unit 3. The head cover member 310 is provided with a capping part 311 for capping the inkjet head area (the area where the nozzle row 41a is formed).

Figure 11 is an explanatory diagram of the head cover member 310. Figure 11(a) is a left side view of the head cover member 310 in an open state, and Figure 11(b) is a bottom view of the same state (a view rotated 90 degrees so that the bottom surface shown in Figure 11(a) is the front). Figure 11(c) is a left side view of the head cover member 310 in a closed state, and Figure 11(d) is a bottom view of the same state (a view rotated 90 degrees so that the bottom surface shown in Figure 11(a) is the front). When the head cover member 310 is closed, it partially covers the print medium contact unit 100 attached to the lower unit 3 from the outside. It has a bottom wall portion 310a, which is the bottom surface in Figure 11(c) in this covering state, and a side wall portion 310b provided upright from both sides in the X-axis direction of the bottom wall portion 310a. An engagement portion 310c is formed on each of the side wall portions 310b. Locking members 32b, 33b of the head cover member 310 are provided on the left side surface 32 and the opposite right side surface 33 of the lower unit 3. A claw at the lower end of each locking member 32b, 33b engages with each engagement portion 310c, and this engagement maintains the capping of the inkjet head area. Each locking member 32b, 33b is configured so that its lower end swings in the X-axis direction with its upper end as the swing fulcrum.

When the print medium contact unit 100 is attached to the main body, the positional relationship between the head cover member 310 and the print medium contact unit 100 is such that the print medium contact unit 100 is located between the lower unit 3 and the head cover member 310. When the head cover member 310 is closed, the head cover member 310 partially covers the print medium contact unit 100 and caps the lower unit 3. Therefore, the presence or absence of the print medium contact unit 100 does not affect the closure of the head cover member 310. Also, by adopting such a positional relationship, it is possible to make it impossible to remove the print medium contact unit 100 when the head cover member 310 is closed.

The range indicated by L3 in FIG. 11(b) is a specific shape range 100d that is recessed (specific shape) more than other areas provided on both sides of the X-axis direction of the opening 100c for exposing the inkjet head 41 in the base member 100a of the print medium contact unit 100 (see FIG. 8(a)). It is desirable to make the width L3 of this specific shape range 100d coincide with the width range L2 of the inkjet area (corresponding to the area of the nozzle row 41a) which is the recording position by the inkjet head 41 as the recording unit. In this way, as shown by the width range L3 in FIG. 11(a), when viewed from the side, the operator can confirm the area of the inkjet head 41 by the unevenness in the vertical direction (the upward recess is L3). In the figure, L1 indicates the distance between the center positions of the roller pair.

In the print medium contact unit 100 described above, the left rotation shaft 37c and the right rotation shaft 38c of the four rollers 37a, 37b, 38a, and 38b are all rotatably attached to the base member 100a. The attachment positions on the base member 100a are fixed in the Z-axis direction, which is the direction of contact and separation with respect to the recording medium. With such a print medium contact unit 100, it has been found that when scanning a recording medium with an uneven surface, such as a surface shape (continuous uneven shape) like the flute structure of cardboard, a problem occurs in which the magnification of the printed image fluctuates.

Figure 1(d) is an explanatory diagram of the state in which an image is formed on a recording medium having an uneven surface. The concave and convex portions are assumed to have an uneven shape extending in a direction perpendicular to the paper surface. The left rotating shaft 37c and the right rotating shaft 38c are also assumed to be scanned in the left-right direction in the figure in a position parallel to the direction perpendicular to the paper surface. When the right side, for example the right second roller 38b, is located in the concave portion and the left side, for example the left second roller 37b, is located in the convex portion, the HMP1 is tilted so that the left side is higher by an angle θ as shown by the auxiliary line for the position detection sensor 18 in the figure. During the travel, the HMP1 may become parallel or incline in the opposite direction, and the distance between the HMP1 main body and the recording medium may change. This causes the direction and distance of the inkjet head 41, which is the recording unit, to change with respect to the recording medium, resulting in a change in the magnification of the image. In this way, it is affected by the unevenness of the recording medium.

Therefore, in this embodiment, the following print medium contact unit 100 is prepared so that the inclination and height variation of the HMP1 body due to unevenness of the print medium can be reduced, and the straightness function of the roller can be improved. In other words, the print medium contact unit 100 is equipped with a contact portion provided on the outer surface with a recording portion so as to contact the recording medium at at least three points, a holding means for holding the roller so that it can be advanced and retreated between a position where it protrudes toward the recording medium side from the contact portion and a position where it does not protrude toward the recording medium side from the contact portion, and a biasing means for biasing the roller toward the protruding position. Because the roller can be advanced and retreated, it is called a roller advancement and retreat type print medium contact unit 100 as necessary.

Figure 1 (a) shows a roller-type print medium contact unit 100 placed on recording paper P. In this state, only the roller is in contact with the print medium, and the sliding part 180, which serves as the contact part, is a certain distance away from the print medium. The sliding part 180 and the bottom part of the roller are at different heights. The bottom part of the roller is closer to the print medium than the sliding part.

Figure 1(b) shows the state in which the HMP1 is pressed downward by a manual pressure F, and the sliding part 180 as a contact part is brought into contact with the recording paper P together with the roller. The roller is biased toward the print medium, and when the HMP1 body is pressed toward the print medium, the position of the roller changes with respect to the HMP1 body including the sliding part 180 in a state in which the roller abuts the print medium. Specifically, the roller moves to the upper side of the HMP1 body by receiving a force from the print medium side. In the initial state, the roller is closer to the print medium than the sliding part 180, but by pressing the HMP1 body, the roller moves to the upper side of the HMP1 body, narrowing the distance between the sliding part 180 and the recording medium. If the HMP1 body is continued to be pressed toward the print medium, the sliding part 180 abuts against the print medium. By the sliding part 180 abutting against the print medium, the positions of the inkjet head 41 and the position detection sensor 18 relative to the print medium are stably determined.

When the roller and sliding part 180 are in contact with the recording medium and scanned over an uneven surface, the roller is constantly biased toward the recording medium, so as shown in FIG. 1(c), the roller moves up and down while following the unevenness of the print medium. As a result, the sliding part 180 is maintained in contact with the print medium, and the positions of the inkjet head 41 and the position detection sensor 18 relative to the print medium, which are determined by this contact, remain stable.

As shown in FIG. 1(a), it is desirable to set the biasing force of the biasing means so that the sliding part 180 can be separated from the recording paper P against the weight of the image forming apparatus when placed on the recording medium. According to this, the HMP1 is placed on the recording medium, the position of the HMP1 is finely adjusted to the position where image formation is to start with the sliding part 180 raised above the recording medium, and then the HMP1 is pressed with pressure force F. When pressed, the roller is in contact with the print medium, so the position of the HMP1 body is unlikely to shift relative to the recording paper P.

Figure 12 is an explanatory diagram of a specific example of a roller-advance/retractable print medium contact unit 100. Figure 12(a) is a left side view of this specific example of the device, seen from the same direction as the print medium contact unit 100 in Figure 11(a) where the roller does not advance/retract, and Figure 12(b) is a bottom view of the same state (a view rotated 90 degrees so that the bottom surface shown in Figure 12(a) is the front). As shown in Figure 12(b), the roller parts (37a, 37b, 38a, 38b) are located outside the main body (lower unit 3) of the HMP1 in the X-axis direction. This is to ensure the vertical movement stroke of the roller parts so that the rollers can follow the uneven surface of the recording medium.

Figure 13(a) is a view of the Y-Y cross section in Figure 12(b) from the direction of the arrow B. Figure 13(b) is an enlarged view of the area C circled by the two-dot chain line in Figure 13(a). As shown in Figure 13(b), the base member 100a is formed with a guide portion 100e that guides the bearing member 190 of the left rotating shaft 37c so that it can move up and down. A biasing member 191 such as a compression spring that presses the bearing member 190 downward is also provided. As shown in an enlarged view on the right side, the bearing member 190 is also formed with a descent stop portion 190a that determines the descent position where the guide portion 100e abuts. Such a structure of the bearing member and guide portion is also provided on the shaft end portion on the other roller 37b side of the left rotating shaft 37c, forming a holding means that holds the roller so that it can move back and forth between a position where it protrudes toward the recording medium side from the contact portion and a position where it does not protrude toward the recording medium side from the contact portion. Also, similar structures are provided on both ends of the right rotating shaft 38c.

Figure 14 is a view of the Z-Z cross section in Figure 12 (b) seen from the direction of the arrow D. The end of the left rotating shaft 37c is inserted and received in the bearing hole 190b of the bearing member 190. The right rotating shaft 38c has a similar structure. Two rollers are attached to the same shaft, and the front and rear rollers on the left and right rotate on the same shaft. Around the periphery of each of the front and rear rollers is a biasing member 191 such as a compression spring as a spring member for pressing the rollers toward the print medium side. This biasing member 191 presses the rollers and bearing parts toward the print medium side. This allows the rollers on the left and right front and rear to follow the unevenness of the print medium. In the example shown, two are attached to the same shaft, but three or more may be attached. Also, in the example shown, the rollers are fixed to the shaft so that they cannot rotate, but they may be attached so that they can rotate. In any case, they are a unit (roller unit) attached to the bearing member 190 as a whole. Instead, each roller may be independently biased by ensuring an independent vertical movement stroke.

The biasing force of the biasing member 191 is set to a level that allows the roller portion to bear the entire weight of the print medium contact unit 100 when the print medium contact unit 100 is attached to the main body of the HMP1 with a full ink cartridge 40 attached, and allows the bottom surface of the base member 100a of the print medium contact unit 100 to be spaced apart from the contact surface. Preferably, the biasing force is set to a level that allows the roller portion to be in the lowest position in this state, determined by the descent stop portion 190a of the bearing member 190 being regulated by the guide portion 100e.

As shown in FIG. 12(b), the bottom surface of the base member 100a is provided with a sliding portion constituting a three-point support portion to allow the HMP1 to assume a position in which the inkjet head 41 faces vertically downward when placed on a horizontal surface. Specifically, a sliding portion 180 is formed on the front surface 35 side of the position detection sensor 18, extending almost the entire width in the width direction (X-axis direction). Between the position detection sensor 18 and the ink head region where the nozzle row 41a is present, short sliding portions 181 and 182 are formed on both sides in the width direction, avoiding the inkjet region. Then, a short sliding portion 183 is formed in the center in the width direction on the rear side of the ink head region. All of the sliding portions protrude from the bottom surface. The protruding heights from the bottom surface are equal to each other.

The arrangement of the sliding parts 180, 181, 182, and 183 can be described as follows. When the image forming device is viewed from the recording medium side, the sliding parts 180, 181, and 182 are provided on one side (+Y direction) of the inkjet head 41 (recording unit) in a direction (Y direction) perpendicular to the scanning direction (X direction) when the user forms an image, and the sliding part 183 is provided on the other side (-Y direction). In addition, the position detection sensor 18 as a detection means for detecting the movement distance and the inkjet head 41 (recording unit) are arranged side by side in a direction (Y direction) perpendicular to the user's scanning direction (X direction), and when the image forming device is viewed from the recording medium side, the sliding part 180 is provided on one side (+Y direction) of the position detection sensor 18 in a direction (Y direction) perpendicular to the scanning direction (X direction), and the sliding parts 181, 182, and 183 are provided on the other side (-Y direction). At least two sliding parts 181, 182 are provided as contact parts between the position detection sensor 18 and the inkjet head 41 (recording part), with the sliding part 182 being arranged on one side (+X direction) of the inkjet head 41 (recording part) or the position detection sensor 18 in the scanning direction (Y direction), and the sliding part 181 being arranged on the other side (-X direction).

It is preferable that each of the above sliding parts is formed from a material that has a smaller coefficient of friction with the recording medium than other parts of the base member 100a. This is to reduce the sliding load and improve linearity. It is also preferable that at least the surface parts of the sliding parts and rollers that come into contact with the recording medium are formed from a fluororesin. Forming with fluororesin can be done by coating. This makes it difficult for ink to adhere, and can prevent ink from being transferred to the recording medium via the rollers and sliding parts.

As shown in FIG. 13(b), when the roller 37a or the like is supporting its own weight, the height level H1 of the sliding parts 181 etc. is above the installation surface level H2 (the surface of the recording material). The urging force of the urging member 191 is set to an extent that the sliding parts 180-183 can be brought into contact with the surface of the recording material by the operator pressing downward with the HMP1 placed on the recording material in this manner. Recording is performed by moving the sliding parts 180-183 in this pressed-down state.

Figure 15 is an explanatory diagram of the pressed-down state of HMP1 in Figure 12. Figure 15(a) is a rear view, Figure 15(b) is an enlarged view of the vicinity of recording paper P when placed on recording paper P and not pressed down, and Figure 15(c) is an enlarged view of the vicinity of recording paper P when pressed down. In the state of Figure 15(b), sliding part 183 is separated from recording paper P. In the state of Figure 15(c), sliding part 183 is in contact with recording paper P. The other sliding parts 181, 182 also contact recording paper P. In this way, HMP1 is moved while sliding parts 181-183 are in contact with recording paper P, and recording is performed.

In the specific example shown in Figures 12 to 15, as shown in Figure 12(a), the side wall portion 140 of the print medium contact unit 100 is also formed in a range that covers the inkjet area in the longitudinal direction (Y-axis direction), and the width range L2 of the side wall portion 140 that faces the inkjet area is recessed inward.

The boundary lines 140a and 140b of the recess can be seen with the naked eye, so they stand out more than the width range L3 of the upper and lower unevenness in FIG. 11. Moreover, in FIG. 12, the boundary line can be set in a range L2 narrower than the width range L3 of FIG. 11, which is closer to the inkjet head area where the nozzle row 41a is formed. By checking the external shape of the print medium contact unit 100, it is possible to check the inkjet area. Since it is only necessary to show the inkjet area, a convex shape may be used instead of a concave shape. The side surface of the print medium contact unit 100 may further be provided with a concave or convex shape corresponding to the width range L3 of the upper and lower unevenness. This makes it easier for the operator to check. Such side shapes of widths L2 and L3 can also be provided in the print medium contact unit 100 of FIG. 11.

As is clear from a comparison of Fig. 12(b) and Fig. 11(b), the roller portion is positioned closer to the front in Fig. 12(b). This is to prevent the portion of the side wall surface portion 310b of the head cover member 310 in Fig. 12(a) that is taller in the vertical direction from interfering with the roller portion that is positioned further outward in the X-axis direction than the main body (lower unit 3) of the HMP1 when the head cover member 310 is closed. As a result of positioning the roller portion closer to the front, the distance between the roller pair is shorter than L1 in the example of Fig. 10(b), as shown by L4 in the figure.

In addition, unlike the example of FIG. 12, the roller parts may be arranged in the same manner as in FIG. 11(b). FIG. 16 illustrates an example of a configuration in which the roller parts are arranged in such a manner. The same reference numerals are used to designate the same members as in FIGS. 11 to 15.

The printing medium contact unit 100 described with reference to Figures 12 to 15 can be set as a permission condition for the recording operation when the sliding parts 180 to 183 are pushed down by the operator to a height where they contact the recording medium. Alternatively, the recording operation can be permitted if the sliding parts 180 to 183 are at a height where they are not in contact but the rollers are in contact. The permission/prohibition control for the above recording operation can be performed by the control board 14 using the output of the position detection sensor 18. In other words, the control board 14 corresponds to a control means that prohibits image formation when the distance of the recording unit to the virtual plane is less than a predetermined value. The prohibited state of the recording operation can be notified to the user by controlling the LED lamp 14a. For example, when the recording operation is prohibited, the LED lamp 14a is turned off and the print button 5a stops emitting light, just as when the HMP1 is removed from the recording material and the position detection sensor 18 can no longer detect the position.

Figure 17 is an explanatory diagram of another example of the print medium contact unit 100. Figure 17(a) is a perspective view of the device of this example seen from approximately the same direction as shown in Figure 7, and Figure 17(b) is a bottom view of the device of this example with the right side 33 facing upward in the figure. The print medium contact unit 100 of this example does not have a roller part, and only has multiple sliding parts 180-183 as the three-point support part, the same as the embodiment of Figures 12 and 13. This contact unit is suitable for cases where the movement operation involves little linear movement and many curved movement scans. In Figure 17, the cover member has been removed, as in Figure 7. Unlike Figure 7, the state in which the ink cartridge 40 and lock member 33b are set is shown.

By preparing different print medium contact units 100 such as those described in Figures 6 to 11, those described in Figures 12 to 15, and those described in Figure 17, and forming a system, it is possible to accommodate a wide variety of scanning methods and also prevent problems with recording media with uneven surfaces.

In the print medium contact unit 100 described above using Figures 1, 12 to 15, a sliding part is provided in the print medium contact unit 100, but the sliding part may be formed in the HMP1 main body, and the print medium contact unit 100 may be provided with an opening that exposes the sliding part of the HMP1 main body to the bottom surface.

In addition, in the HMP1 equipped with the print medium contact unit 100 described using Figures 1, 12 to 15, the rollers can be made to follow the surface irregularities of the recording medium, thereby suppressing defects caused by surface irregularities. However, instead of using the print medium contact unit 100, it is also possible to provide the HMP1 main body with rollers and sliding parts, and to provide holding means for these rollers that can move between a position where the rollers protrude toward the recording medium side from the sliding part and a retracted position, and biasing means for biasing the rollers toward the protruding position.

In addition, in this embodiment, an example of applying the present invention to an inkjet type HMP10 has been described, but the configuration of the present invention can also be applied to devices using other image forming methods. For example, it can be applied to recording devices using appropriate methods such as a thermal type or a thermal transfer type.

1: HMP
2: Upper unit 2a: Horizontal extension portion 2b: Vertical extension portion 3: Lower unit 3a: Upper unit rotating shaft 5a: Print button 5b: Power button 5c: LED lamp 11: Upper unit locking claw 13: FPC contact portion 14: Control board 14a: LED lamp 15: Battery 15a: USB connection port 18: Position detection sensor 25: Flexible flat cable 30: Lower surface 30a: Opening 32: Left side surface 32b: Locking member 33: Right side surface 33b: Locking member 34: Rear surface 35: Front surface 37a: Left first roller 37b: Left second roller 37c: Left rotating shaft 38a: Right first roller 38b: Right second roller 38c: Right rotating shaft 40: Ink cartridge 41: Inkjet head 41a: Ejection hole row 52: Bt board 75: Spacer member 76 : Protrusion 80 : Housing 100 : Printing medium contact unit 100a : Base member 100b : Opening 100c : Opening 100d : Specific shape range 100e : Guide portion 110 : Hook portion 110a : Vertical portion 110b : Horizontal portion 120 : Hook portion 120a : Hook hole 121 : Operation portion 121a : Shaft portion 123 : Stop member 124 : Claw member 124a : Claw portion 124b : Tapered portion 125 : Compression spring 130 : Side wall portion 130a : Guide hole 131 : Front side wall portion 132 : Storage portion 140 : Side wall portion 140a : Boundary line 140b : Boundary line 152 : Board 153 : RAM
154: ROM
155: CPU
156: recording control section 157: gyro sensor 158: capping sensor 180: sliding section 181: sliding section 182: sliding section 183: sliding section 190: bearing member 190a: descent stop section 191: biasing member 210: hook plate section 210a: hook hole 220: hook plate section 220a: hook hole 220b: tip section 220c: side surface 300: mounting section 301: rotating shaft 310: head cover member 310a: bottom wall section 310b: side wall section 310c: engagement section 311: capping section A: arrow A7: arrow B: arrow C: range H1: height level H2: installation surface level L2: width range L3: width range P: recording paper

JP 2019-155890 A

Claims (15)

An image forming apparatus including a recording unit for recording an image and a rotatable roller on a side facing a recording medium,
a contact portion provided so as to come into contact with the recording medium at at least three points;
a holding means for holding the roller so as to be movable between a position where the roller protrudes toward the recording medium from the contact portion and a position where the roller does not protrude toward the recording medium from the contact portion;
a biasing means for biasing the roller toward the protruding position;
An image forming apparatus comprising: 2. The image forming apparatus according to claim 1,
an image forming apparatus, wherein said roller, said holding means and said biasing means are provided on an installation part which is detachably attached to a main body of the image forming apparatus as one unit; 3. The image forming apparatus according to claim 2,
An image forming apparatus, comprising: the installation part provided with the contact portion. 4. The image forming apparatus according to claim 1,
An image forming apparatus, characterized in that the biasing force of the biasing means is set so that, when placed on a recording medium, the contact portion can be separated from the recording medium against the weight of the image forming apparatus itself. 5. The image forming apparatus according to claim 1,
The image forming apparatus according to claim 1, wherein the contact portion is made of a material having a smaller coefficient of friction with the recording medium than other portions on the opposing side. 6. The image forming apparatus according to claim 1,
At least one of the contact portion and the roller has a surface made of a fluorine-based resin. 7. The image forming apparatus according to claim 1,
An image forming apparatus comprising: an image forming unit that forms an image on a recording medium while moving the roller along with the rotation of the roller. 8. The image forming apparatus according to claim 7,
1. An image forming apparatus comprising: a position detection means for detecting a position on a recording medium; and a drive control means for controlling the drive of said recording section based on a detection result of the position detection means. 9. The image forming apparatus according to claim 1,
The image forming apparatus is characterized in that at least two of the rollers are attached to one of the rotation shafts to form a roller unit. 10. The image forming apparatus according to claim 1,
the image forming device records an image by scanning in a scanning direction;
an image forming apparatus, characterized in that, when the image forming apparatus is viewed from the recording medium side, the contact portions are provided on one side and the other side of the recording unit in a direction perpendicular to the scanning direction. 11. The image forming apparatus according to claim 1,
the image forming device records an image by scanning in a scanning direction;
a detection unit for detecting a moving distance of the image forming apparatus,
The detection means and the recording unit are arranged side by side in a direction perpendicular to the scanning direction,
An image forming apparatus characterized in that, when the image forming apparatus is viewed from the recording medium side, the contact portions are provided on one side and the other side of the detection means in a direction perpendicular to the scanning direction. 12. The image forming apparatus according to claim 1,
the image forming device records an image by scanning in a scanning direction;
a detection unit for detecting a moving distance of the image forming apparatus,
The detection means and the recording unit are arranged side by side in a direction perpendicular to the scanning direction,
2. An image forming apparatus comprising: at least two contact portions provided between said detecting means and said recording unit in said orthogonal direction. An image forming apparatus main body to which a removable unit having at least one of a recording unit and a recording material container used in a recording unit for recording an image on a recording medium is detachably attached,
A rotatable roller;
a contact portion provided so as to come into contact with the recording medium at at least three points;
a holding means for holding the roller so as to be movable between a position where the roller protrudes toward the recording medium from the contact portion and a position where the roller does not protrude toward the recording medium from the contact portion;
and a biasing means for biasing the roller toward the protruding position. a housing to which a removable unit having at least one of a recording unit that records an image on a recording medium and a recording material storage unit used in the recording unit is detachably attached;
a contact portion provided so as to come into contact with the recording medium at at least three points;
and two or more installation parts selectively attached to the housing,
At least one of the two or more installation parts is
A rotatable roller;
a holding means for holding the roller so as to be movable between a position where the roller protrudes toward the recording medium from the contact portion and a position where the roller does not protrude toward the recording medium from the contact portion;
and a biasing means for biasing the roller toward the protruding position. An installation part to be attached to a side of an image forming apparatus facing a recording medium, the image forming apparatus including a recording unit that records an image on the recording medium,
a contact portion provided so as to come into contact with the recording medium at at least three points;
A rotatable roller;
a holding means for holding the roller so as to be movable between a position where the roller protrudes toward the recording medium from the contact portion and a position where the roller does not protrude toward the recording medium from the contact portion;
and biasing means for biasing the roller toward the extended position.

Images