JP4847269B2 - Sheet conveying method and apparatus - Google Patents

Description

  The present invention relates to a sheet conveying method and a conveying apparatus that are used when a sheet having a fixed size is supplied from a sheet supply source to a first process press machine of a press machine.

  Conventionally, as shown in FIG. 7, a fixed-size sheet 102 supplied from a sheet supply source to a first press machine of a press machine by a conveying device can be corrected in advance to a regular posture on an idle stage 104. It was done.

  The conveying apparatus 100 having such a sheet posture correcting function has a plurality of actuators 105 opposed to an upper surface of an idle stage 104 on which a sheet is placed, and is arranged outside a substantially trapezoidal sheet having corners. The peripheral edge is pressed inward for positioning.

For example, pneumatic and hydraulic cylinders are used as the actuator 105, and the pneumatic and hydraulic cylinders are controlled to position the seat 102 in a normal posture.
Specifically, the sheet is positioned in a normal posture by controlling the actuator by pressing the contact portion 105a at the tip of each rod of each of the plurality of actuators against the outer peripheral edge of the sheet placed on the idle stage 104. Is possible.

As described above, in the conveying apparatus 100 employing the mechanical method, a hydraulic cylinder is used as an actuator, and the outer periphery of the sheet 102 is pressed and positioned by individual rods.
Therefore, there is a problem that the contact portion 105a at the tip of each rod acts as an excessive load on the outer peripheral edge of the sheet 102, and a dent or a scratch is generated at the pressed portion.
Further, when the sheet 102 has a complicated shape, it is necessary to increase the number of actuators in order to correspond to the outer shape, resulting in a complicated structure.
Along with that, there were various problems such as increased wiring, piping, etc., increasing construction costs and making maintenance difficult.

For this reason, a sheet conveying apparatus having a relatively simplified arrangement has been proposed (see Patent Document 1).
In this sheet conveying apparatus, abutting bodies (including rollers) are arranged in the vicinity of each of the four corners of the sheet, and each abutting body is equal to each side surface near the corner of the sheet. The sheet can be positioned in an appropriate posture by being moved and pressed.

JP-A-9-150340

However, although the sheet conveying apparatus described in Patent Document 1 has a simplified arrangement configuration, it employs a mechanical positioning mechanism to position the sheet, The problem is still not resolved.
For this reason, a conveyance device that does not employ a mechanical positioning mechanism by pressing the peripheral side surface of the sheet has been desired.
However, if the positioning mechanism is not employed, the sheet placement posture varies on the idle stage, and when the sheet is gripped, the conveying device cannot be gripped in an appropriate state.
As a result, there is a problem in that the vacuum pad provided in the transport device comes off the sheet and causes a suction failure, which needs to be solved.

  The present invention has been made in view of such circumstances, and a sheet conveying method and apparatus capable of gripping a sheet in an appropriate state by a gripping portion of the conveying apparatus without using a mechanical positioning mechanism as in the prior art. Is intended to provide.

  Thus, as a result of earnest research on the background of such problems, the present inventor has corrected the above-mentioned problems by correcting the position of the grip portion according to the posture position on which the sheet is placed. The present invention has been completed based on this finding.

That is, the present invention is Li, (1), a sheet conveying apparatus for supplying a sheet of a fixed size supplied and mounted on an idle stage from a sheet supply source to a press machine, the sheet on the idle stage. comprising a plurality of CCD cameras for imaging the attitude position of said plurality of CCD cameras disposed below the mounting surface of the idle stage, the mounting surface of the upper Symbol idle stage, at least on the placing The supply sheet on the surface is made of a translucent material that can be imaged by the CCD camera, and a light source is disposed above the mounting surface of the idle stage, and is mounted on the mounting surface when the CCD camera is imaged. so as to throw light from location to supply sheet upper surface toward the CCD camera, the CCD camera, which captures at least two corners of the sheet, these CC A control device that captures two imaging coordinates that are corners of the sheet imaged by the camera, and in the control device, the model sheet positioned as a normal position on the idle stage previously captured in the storage unit; Sheet that grips the sheet on the idle stage by comparing and calculating the amount of deviation between the coordinates of the two points serving as corners and the imaging coordinates of the two points, and correcting and controlling the gripping portion of the conveying device by the amount of deviation Exist in the transport device.

Further, the present invention is (2), the said pressing machine is a tandem press machine (1) lies in the conveying device for a seat according.

The present invention also relates to (3), the said pressing machine is a transfer press machine (1) lies in the conveying device for a seat according.

The present invention also relates to ( 4 ) a sheet conveying method for supplying a fixed-size sheet supplied and placed on an idle stage from a sheet supply source to a press machine, wherein the sheet on the idle stage is A plurality of CCD cameras having at least two corners disposed below a mounting surface made of a light-transmitting material of the idle stage, and are mounted above the light source disposed above the mounting surface of the idle stage. On the idle stage, which is projected from the upper surface of the supply sheet placed on the surface toward the CCD camera and picked up an image, the two imaging coordinates are taken into the control device, and are taken into the storage unit of the control device in advance. The shift amount between the coordinates of the two points that are the corners of the model sheet positioned as the normal position and the imaging coordinates of the two points is compared and calculated, and the gripping portion of the transport device is moved by the shift amount. Positive control to reside in a sheet conveying method which is adapted to grip the donor sheet on the idle stage.

In addition, as long as the objective of this invention is followed, the structure which combined suitably said (1)-( 4 ) is also employable.

  According to the sheet conveying method and apparatus of the present invention, since a plurality of CCD cameras for imaging the posture of the sheet on the idle stage are provided, the posture position of the sheet can be fed back to the conveying device as imaging coordinate information. .

  The CCD camera captures at least two corners of the sheet, and includes a control device that captures imaging coordinates of two points that are corners of the sheet imaged by the CCD camera. Comparing and calculating the amount of deviation between the coordinates of the two points serving as the corners of the model sheet positioned as the normal position on the idle stage previously captured in the storage unit and the imaging coordinates of the two points, Since the gripping part is corrected and controlled by the amount of deviation, the sheet on the idle stage is grasped, so that a conventional positioning device is not required for the idle stage, and the sheet is properly displaced by a simplified device. It is possible to grip in the absence of

FIG. 1 is a plan view showing an arrangement configuration of a plurality of press machines configured in a line and an apparatus for conveying sheets supplied from a sheet supply source to the press machines.
FIG. 2 is a perspective view showing a schematic configuration of the sheet conveying apparatus.

As shown in FIG. 1, the press processing line R2 of the press processing apparatus 1 is configured by arranging a plurality of (four in this embodiment) press machines 2A, 2B, 2C, and 2D in parallel at predetermined intervals. Yes.
In the press processing line R2, for example, sheet drawing is sequentially performed.
This processing line is a tandem press processing device line consisting of multiple press processing machines with different processing times in the figure, but a transfer press processing device with a constant processing time (tact time) is provided. A line configuration is also possible.

A sheet is supplied to the pressing line R2 from a sheet carry-in line R1 that is a sheet supply source via an idle stage S (specifically, a sheet placing table 10) described later.
Examples of the sheet include an iron plate and an aluminum plate. Specifically, for example, an iron-shaped sheet having a thickness of 0.5 to 4 mm and having a thickness of about 2000 mm × 4000 mm is used.

In the present embodiment, the supply sheet W is described as an example of a regular supply sheet W formed in a quadrangular shape close to a substantially trapezoid as shown in FIG.
In the sheet carry-in line R1, a direction substantially orthogonal to the press processing line R2 is a conveyance direction, and the supply sheet W is continuously conveyed on the sheet carry-in line R1 as described above.
Further, a sheet unloading line R3 for unloading the pressed product that has been pressed is disposed behind the press machine 2D that executes the last process of the press line R2.

  Between the sheet carry-in line R1 and the idle stage S on which the supply sheet placement table 10 is provided, the supply sheet W sent through the sheet carry-in line R1 is gripped and supplied to the table 10 described above. A sheet supply device 4 is disposed.

The sheet supply apparatus 4 grips the supply sheet W sent on the sheet carry-in line R1, and then rotates the arm portion 4A and the like to transfer the supply sheet W onto the idle stage S.
In this case, on the idle stage, the seat may be placed at a posture position different from the appropriate position (that is, a position shifted from the position of the model seat described later).

  Further, between the idle stage S and the press machine 2A that performs the initial process, the supply sheet W supplied from the sheet carry-in line R1 to the idle stage S (specifically, on the mounting table 10) is supplied to the press machine 2A. The first transfer robot 5A is disposed here.

The first delivery robot 5A has basically the same structure as that of the sheet feeding device 4, and the rotation shaft (not shown) of the angle adjusting device G provided at the tip of the arm portion 5A1 A central portion of the linear support member 5A2 is attached.
The support member 5A2 is provided with a plurality (four in the figure) of attachment members 5A3 at regular intervals in a direction orthogonal to the longitudinal direction of the support member 5A2.
Then, a pair of vacuum pads 5A4 facing downward are provided at both ends in the length direction of these attachment members 5A3.
These vacuum pads 5A4 are arranged so as to be able to adsorb a standard-sized supply sheet W in a balanced manner.

Further, between the press machine 2A and the press machine 2B, between the press machine 2B and the press machine 2C, and between the press machine 2C and the press machine 2D, the sheet W that has been press-processed in the previous step is respectively used. A transfer device for transferring to the next process, that is, a second transfer robot 5B, a third transfer robot 5C, and a fourth transfer robot 5D are arranged.
Between the last press machine 2D and the sheet carry-out line R3, a fifth delivery robot 5E for delivering the sheet W that has been subjected to the press process to the sheet carry-out line R3 is disposed.

The supply sheet W is taken out from the sheet carry-in line R <b> 1 and then placed on the mounting table 10 of the idle stage S by the supply device 4.
Two CCD (Charge Coupled Device) cameras for imaging the positions of at least two corners of the supply sheet W are attached to the lower surface of a top plate 15 (to be described later) of the mounting stage 10 of the idle stage S. Yes.
In the figure, an example in the case of diagonal positions (corner sections facing each other) as the positions of the two corners is shown.

Here, in the mounting table 10, the top plate 15 is horizontally provided at the upper ends of the four support columns 12 erected at the four corners of the sheet metal base 18 laid on the floor surface.
In addition, a square-shaped opening 16 formed substantially at the center of the top plate 15 is provided with a wire net-like translucent mounting plate 14 having a predetermined strength.
The outer shape of the supply sheet W placed on the top plate 15 can be viewed from below through the placement plate 14 and can be easily imaged with a CCD camera.
The mounting plate 14 is not limited to a wire mesh structure, and any mounting material can be used as long as the mounting surface is flat and has a supporting strength and a light-transmitting material.

FIG. 3 is a diagram for explaining a system in which the position of a sheet is imaged by a CCD camera and the shift amount is corrected and controlled by a conveyance device.
FIG. 4 is an explanatory diagram showing a deviation amount between two reference points that are corners of the model sheet and two points that are measured corresponding corners of the supplied sheet.

As shown in FIG. 3, the two CCD cameras 8a and 8b described above are attached to the front and rear surfaces of the plate 14 via a pair of brackets 17a and 17b.
As shown in the figure, these two CCD cameras 8a and 8b are connected to a control device N. The control device N includes a central processing unit CPU and an arithmetic processing unit (not shown) provided in a normal control device. A storage unit, an image processing unit, an input / output device (keyboard, display), and the like, which are connected to the drive unit H of the first delivery robot 5A.

The movement of the arm portion 5A1 of the first delivery robot 5A is controlled via the drive unit H in response to a command from the control device N, and the supply sheet W that has been imaged on the idle stage S is transferred to the arm portion 5A1. Adsorption is performed by the eight vacuum pads 5A4 of the support member 5A2, which is a grip portion at the tip of the arm portion 5A1.
The eight vacuum pads 5A4 can be controlled to rotate at a predetermined angle around the rotation axis by the diagonal adjustment device G as a whole.

As shown in FIG. 4, the supply sheet W mounted on the mounting table 10 of the idle stage S is imaged through the mounting plate 14 by the two CCD cameras 8a and 8b.
The coordinates of the two diagonal points [A ′, B ′] as the measurement points of the imaged supply sheet W are taken into the control device N.
However, the coordinates of the two points [A, B] which are the diagonals of the model sheet MW on the idle stage are captured and stored in the control device N in advance.

Similarly, the position of the grip portion when gripping the model sheet MW is captured and stored in the control device.
Specifically, any two reference position coordinates (for example, the position coordinates of the angle adjusting device G and one of the vacuum pads 5A4 among the eight vacuum pads 5A4) when the model sheet MW is gripped at an appropriate position by the gripping portion. Position coordinates) is taken in and stored in the control device.
Therefore, in the above control device, two points [diagonal of the supplied sheet W] with respect to two reference points [A, B] that are diagonally captured by the model sheet MW previously captured as a normal posture [ A ′, B ′] is compared and calculated by the image processing unit of the control device N.
And the amount of deviation is calculated.

That is, in the image processing unit of the control device N, the coordinates A ′ (X1 ′, Y1 ′), B ′ (2) [A ′, B ′] that are diagonal as the measurement points of the captured supply sheet W are measured. X2 ′, Y2 ′) are the coordinates A (X1, Y1) and B (X2, Y2) of the two points [A, B] that are the diagonals of the model sheet MW previously stored in the storage unit of the control device N. And the amount of deviation is obtained.
Note that the X and Y coordinates described above are obtained by setting an arbitrary reference position on the mounting table 10 as the origin O.

When the deviation amount is obtained as described above, the driving unit H is controlled by the control device N, and the position of the gripping portion (the position where the model sheet is properly gripped) is corrected based on the deviation amount. At the appropriate position.
The correction is corrected from the position for properly holding the model sheet to the position for holding the supply sheet W at the appropriate position.

  Thereafter, the supply sheet W gripped by the gripper is supplied to the processing position of the press machine 2A.

By the way, in the idle stage S, it is preferable to set it as the structure which has arrange | positioned the light source above the mounting base 10. FIG.
Thus, when the supply sheet W is imaged through the mounting plate 14 by the CCD cameras 8a and 8b below the mounting table 10, the light source disposed above the mounting plate 14 is directed toward the CCD cameras 8a and 8b. Since the light is projected, it is possible to image the supply sheet W in a backlight state.
Therefore, the color of the supply sheet W and the influence of disturbance light can be reduced.

The two points that are diagonal to the reference point of the model sheet MW may be based on at least two corners of the model sheet MW.
The reference points of the model sheet MW may be two points at two adjacent corners instead of the two diagonal points.

  FIG. 5 is an explanatory diagram showing the amount of deviation between the coordinates of the two adjacent corners of the supplied sheet relative to the coordinates of the two adjacent corners of the model sheet.

In FIG. 5, in the image processing unit of the control device N, the coordinates A ′ (X1 ′, Y1) of two points [A ′, B ′] that are adjacent corners taken in as the measurement posture of the captured supply sheet W are captured. '), B' (X2 ', Y2') with respect to the imaging coordinates, coordinates A (X1, Y1) of two points [A, B] that are adjacent corners of the model sheet MW previously taken into the control device , B (X2, Y2) is obtained by a comparison operation.
As described above, the gripping unit is corrected based on the amount of deviation and can grip the supply sheet W at an appropriate position.

  FIG. 6 is a flowchart showing a procedure (method) for correcting and controlling the supply sheet by the conveying device.

In FIG. 6, first, when the drive unit H of the sheet supply device 4 is driven, in step ST1, the movement of the arm portion 4A is controlled by a command from the control device N, and the supply sheet W on the sheet carry-in line R1 is changed. It is adsorbed by the vacuum pad 4D and supplied onto the idle stage S.
In this case, it is assumed that the supply sheet W is in a posture position that is shifted from the model sheet MW.

  In step ST2, the supply sheet W supplied onto the idle stage S is imaged from the lower surface side by the two CCD cameras 8a and 8b, and two points [A ′, B ′] that are opposite to the supply sheet W are taken. Obtain imaging coordinates.

  In the next step ST3, the coordinates of the two points [A, B] on the diagonal of the model sheet MW positioned as the normal position on the idle stage previously fetched in the storage unit are supplied on the idle stage S. The imaging coordinates of the two points [A ′, B ′] of the supplied sheet W are compared and calculated, and the amount of deviation between the two sheets is obtained.

In step ST4, when the amount of deviation between the coordinates of the two points is obtained in step ST3, the grip portion of the arm portion 5A1 of the first delivery robot 5A is corrected and controlled by the amount of deviation based on this, and the idle stage The supply sheet W on S is gripped.
In this case, as described above, the gripper grips the supply sheet W on the idle stage S with the position corrected by the shift amount with reference to the grip position of the model sheet MW.
This completes the routine for correction control by the transport device.

  As described above, according to the sheet conveying apparatus described in the above embodiment, a plurality of, for example, two CCD cameras, each having two diagonals of the supply sheet W supplied and placed on the idle stage S from the sheet carry-in line R1. Images are taken at 8a and 8b, and the image pickup coordinates of the two points [A ′, B ′] are taken into the control device N.

  Next, the imaging coordinates of the two points [A ′, B ′] and the two points [A, B] which are diagonally opposite to the model sheet MW on the idle stage S previously fetched into the storage unit of the control device N. The amount of deviation of the coordinates is obtained.

The amount of deviation between the coordinates of the two points serving as the corners of the model sheet positioned as the normal position on the idle stage previously captured in the storage unit and the imaging coordinates of the two points is compared and calculated, and The grip portion is corrected and controlled by the amount of deviation so as to grip the sheet on the idle stage.
As described above, when a conventional mechanical positioning device is not required at all, it is possible to grip the sheet without a proper shift by a simplified device, which is extremely useful.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.
For example, the corner to be imaged depends on the shape of the supply sheet, which is a workpiece, but at least two of the plurality of corners may be selected, and the CCD camera selects the selected corner. What is necessary is just to be able to image.
The structure of the mounting table 10 on the idle stage can be changed as long as the supply sheet mounted on the mounting table can be imaged by the CCD camera.

FIG. 1 is a plan view showing an arrangement configuration of a plurality of press machines configured in a line according to an embodiment of the present invention and a conveyance device that conveys a sheet supplied from a sheet supply source to the press machine by controlling its posture. It is. FIG. 2 is a perspective view illustrating a schematic configuration of the sheet conveying apparatus according to the embodiment of the present invention. FIG. 3 is a diagram for explaining a system for taking an image with a CCD camera according to an embodiment of the present invention and correcting and controlling a deviation amount with a feeding device. FIG. 4 is an explanatory diagram showing a deviation amount between two reference points that are corner portions of the model sheet and two measured corner portions of the supplied supply sheet in the embodiment of the present invention. . FIG. 5 is an explanatory diagram showing the amount of deviation between the coordinates of the two adjacent corners of the supplied sheet with respect to the coordinates of the two adjacent corners of the model sheet in the embodiment of the present invention. FIG. 6 is a flowchart showing a procedure for correcting and controlling the supply sheet by the transport device according to the embodiment of the present invention. FIG. 7 is a plan view showing a conventional sheet conveying apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Press processing apparatus 2A, 2B, 2C, 2D ... Press processing machine 4 ... Sheet supply apparatus 5A ... 1st delivery robot 5A1 ... Arm part 5A2 ... Support member 5A3 ... Mounting member 5A4 ... Vacuum pad 5B-5E ... 2nd-2nd 5th delivery robot 8a, 8b ... CCD camera 10 ... mounting table 12 ... column 14 ... mounting plate 15 ... top plate 16 ... square opening 17a, 17b ... bracket 18 ... base G ... angle adjusting device H ... drive unit N ... Control device MW ... Model sheet R1 ... Sheet carry-in line R2 ... Press processing line R3 ... Sheet carry-out line S ... Idle stage W ... Supply sheet

Claims (4)

A sheet conveying device for supplying a sheet of a fixed size supplied and placed on an idle stage from a sheet supply source to a press machine,
A plurality of CCD cameras for imaging the posture position of the sheet on the idle stage,
The plurality of CCD cameras are disposed below the mounting surface of the idle stage ,
The mounting surface of the upper Symbol idle stage is fed sheets on at least the mounting surface is made of a material of the imageable translucency by the CCD camera,
A light source is disposed above the mounting surface of the idle stage so that light is projected toward the CCD camera from the upper surface of the supply sheet placed on the mounting surface when the CCD camera is imaged .
The CCD camera images at least two corners of the sheet, and includes a control device that captures imaging coordinates of two points that are corners of the sheet imaged by the CCD camera,
The control device compares and calculates the amount of deviation between the coordinates of the two points that become the corners of the model sheet positioned as the normal position on the idle stage that has been previously captured in the storage unit and the imaging coordinates of the two points. A sheet conveying apparatus characterized in that the sheet on the idle stage is gripped by controlling the gripping portion of the conveying apparatus by the amount of deviation .   The sheet conveying apparatus according to claim 1, wherein the press machine is a tandem press machine.   2. The sheet conveying apparatus according to claim 1, wherein the press machine is a transfer press machine. A sheet conveying method for supplying a sheet of a fixed size supplied and placed on an idle stage from a sheet supply source to a press machine,
A plurality of CCD cameras in which at least two corners of the sheet on the idle stage are disposed below the mounting surface made of a light-transmissive material of the idle stage, and are disposed above the mounting surface of the idle stage. The light source projects the light from the upper surface of the supply sheet placed on the placement surface toward the CCD camera, captures the two imaging coordinates into the control device, and stores them in the storage unit of the control device in advance. Comparing and calculating the amount of deviation between the coordinates of the two points serving as the corners of the model sheet positioned as a normal position on the captured idle stage and the imaging coordinates of the two points, A sheet conveying method, characterized in that a correction sheet is controlled by an amount of misalignment to hold the supplied sheet on the idle stage.

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