JPH03245984A - Work loading method - Google Patents

Abstract

PURPOSE:To remove the strain caused on a work by pressing and to improve the quality of the work, by performing a heat treatment on the work on the way of the work being transferred to the unloading position of a conveyor device from a press machine. CONSTITUTION:A heat treatment is performed by a heat treatment device 3 on a work W on the way of the work W being transferred from a press machine to the unloading position of a conveyor device. Thereafter, the infrared pattern of this work W is subjected to image processing by an image processing device 6 and the infrared pattern subjected to image processing is recognized as the position and direction of the work W in comparison with the basic pattern in a control unit 8 and the direction and the holding position of a hand robot 7 to the work W are controlled in accordance with this recognized result.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a workpiece loading method in which a hand robot picks up a workpiece from a conveyor device and loads the workpiece onto a pallet.

Conventional technology Works that are integrally constructed by hemming the inner panel and outer panel using a press machine, such as a hood or trunk lid as vehicle body components, are large and heavy, so it is difficult to use a press machine. The workpiece discharged from the machine is conveyed to a pallet placed on the installation floor using a conveyor device such as a belt conveyor, and when the workpiece is conveyed to the unloading position of the conveyor device, the conveyor device is stopped. Irradiate the workpiece with light at this position,
The reflection pattern of this workpiece is imaged with a COD camera, the position and orientation of the workpiece are recognized from this image, and the gripping position and orientation of the hand unit of the hand robot with respect to the workpiece is controlled according to the recognition result, and the hand The unit grasps the workpieces on the conveyor device and loads them onto the pallet.

Problems to be Solved by the Invention Workpieces such as hoods and trunk lids that constitute vehicle body components often have curved surfaces. The reflection pattern of this workpiece with many curved surfaces is C.
When imaging with an OD camera, a local part of the workpiece causes specular reflection, and the COD camera receives halation, which may make it impossible to recognize the position and orientation of the workpiece.

Means for Solving the Problem The work discharged from the press machine is conveyed toward the pallet by a conveyor device, and when the workpiece is conveyed to the unloading position of the conveyor device, the conveyor device is stopped, and the conveyor device is stopped. In a workpiece loading method in which a workpiece stopped at an unloading position is gripped by a hand unit of a hand robot and loaded onto a pallet, the workpiece is subjected to heat treatment while being transported from the press machine to the unloading position of a conveyor device. After performing image processing on the infrared pattern of this workpiece, this image-processed infrared pattern is compared with the basic pattern to recognize the position and orientation of the workpiece, and the hand unit grips the workpiece according to this recognition result. Control position and orientation.

Embodiment Figures 1 to 3 are block diagrams showing an embodiment of the entire system used in the workpiece loading method of the present invention. It includes a device 3, a third conveyor device 4, an infrared camera 5, an image processing device 6, a hand robot 7, a line control device W8, and a pallet 9.

The first conveyor device I conveys a workpiece W discharged from a press machine (not shown) to the heat treatment device 3 side, and includes a pair of left and right conveyor belts la. Each of the conveyor belts la is straddled over a driving pulley ld and a driven pulley le, which are attached to the front and rear ends of the left and right side frames lc at the top of the device body 1b placed on the installation floor. There is. For each drive pulley ld,
An output shaft of a motor Ig that is attached to a front frame If that is horizontally suspended across the front ends of the left and right side frames lc and rotates synchronously is connected thereto. This motor Ig is driven and controlled by a line control device 8. In other words, when a work discharge signal is input from the press machine side to the line control device w8, the line control device 8 rotates the motor 1g, and the rotation of this motor 1g drives the conveyor belt la. , the workpiece W discharged from the press machine is conveyed in the direction of the heat treatment apparatus 3 shown by the arrow in FIG. Further, a first work sensor lh is attached to the upper surface of the front end of at least one of the left and right side frames lc. When the detection signal of this first work sensor lh is output to the line control device 8,
The line control device 8 rotates the motor 2h of the second conveyor device 2.

The second conveyor device 2 transports the work W received from the first conveyor device l into the heat treatment device 3, and also transports the work W that has been heat-treated in the heat treatment device 3 to the third conveyor device 4. It is provided with a pair of left and right conveyor belts 2a.

This conveyor belt 2a is raised and lowered by a lift cylinder 2b attached to a substantially central portion of a base plate 3d of the heat treatment apparatus 3 so as to be aligned in the vertical direction. Specifically, a movable frame 2d is attached to an operating rod 2c that protrudes above the lift cylinder 2b. This movable frame 2d
The pair of left and right conveyor belts 2a are straddled over a driving pulley 2f and a driven pulley 2g attached to the front and rear ends of the left and right side frames 2e.

Each drive pulley 2r has a left and right side frame 2e.
The output shaft of a motor 2h that is attached to a front frame (not shown) that is horizontally suspended across the front end of the motor 2h and rotates synchronously is connected thereto. This motor 2h is driven and controlled by a line control device 8. Here, the conveyor belt 2a protrudes above the apparatus main body 3c of the heat treatment apparatus 3 at the lifting limit position where the lift cylinder 2b is extended, and is disposed at a height between the conveyor belt la of the first conveyor unit W1 and the path. Then, the workpiece W is received from the first conveyor device 1 and discharged to the third conveyor device 4, while the conveyor belt 2a enters the main body 3c of the heat treatment device 3 at the lowering limit position where the lift cylinder 2b is contracted and is heat treated. The workpiece W placed on the workpiece support table 3h of the apparatus 3 is freely disposed below the workpiece W. Further, on the upper surface of the front end of at least one of the left and right side frames 2e,
A work sensor 21 is attached. When the workpiece detection signal from the second workpiece sensor 21 is output to the line control device 8, the line control device 8 stops the motors Ig and 2h of the first and second conveyor devices 1.2 and contracts the lift cylinder 2b. drive In other words, in a state where the second conveyor device 2 is stopped at the upper limit position, the first conveyor device 2
The workpiece detection signal from the workpiece sensor Ih is sent to the line control device 8.
, the line control device 8 rotates the motor 2h of the second conveyor device 2, and the rotation of this motor 2h drives the conveyor belt 2a.
The workpiece W is transferred from the first conveyor device to the second conveyor device 2 by the drive of a, and this workpiece W is completely transferred to the second conveyor device 2 as shown by the dashed line in FIG. When W reaches a predetermined position where it can be placed on the workpiece support stand 3h of the heat treatment device 3 as shown by the imaginary line in FIG. 2, the second workpiece sensor 21 of the second conveyor device 2 detects the workpiece W as described above. Then, this workpiece detection signal is output to the line control device 8. Then, the line control device 8 switches to the first. Motor 1 of the second conveyor device 1, 2. g and 2h are stopped, and the lift cylinder 2b is driven to contract. In the process of the second conveyor device 2 moving from the upper limit position to the lower limit position, the work W on the second conveyor device 2 is stored in the space 3e of the heat treatment device 3 and is not received by the work support stand 3h. After the line control device 8 stops the lift cylinder 2b at the lowering limit position, the high frequency power source 3a of the heat treatment device 3 is turned on after a predetermined time delay.
Outputs a heat treatment signal to Next, after heat treatment is applied to the workpiece W, the line control device 8 drives the lift cylinder 2b to extend from the lower limit position, and in the process of extending the lift cylinder 2b from the lower limit position to the upper limit position,
The conveyor belt 2a of the second conveyor device 2 lifts the workpiece W from the workpiece support base 3h. After the line control device 8 stops the lift cylinder 2b at the upper limit position, the second. Conveyor belt 2a of third conveyor device 2°4
, 4a. Then, the work W is transferred from the second conveyor device 2 to the third conveyor device 4.

The heat treatment device 3 is operated while the workpiece W is being conveyed from the press machine to the unloading position T of the third conveyor device 4.
The workpiece W is subjected to heat treatment, and in this embodiment, the workpiece W is composed of an inner panel and an outer panel.
In order to remove the distortion caused by the hemming process of the press machine, annealing is performed on the periphery of the workpiece W, which is the hemmed part. A high frequency current is supplied to 3b to inductively heat the peripheral portion of the workpiece W into the annealing greenhouse. The coil 3b is formed of a single copper pipe in two stages, upper and lower, having a similar shape to the outer shape of the work W when viewed from the plane, and cooling water is allowed to flow inside the single copper pipe. Further, the coil 3b is attached to the device main body 3c.

This device body 3c includes a base plate 3d disposed on the installation floor in front of the first conveyor device l in the conveying direction, and an upper open space 3e on which the workpiece W can be stored in a loose state. wall 3f defining
has been erected. As shown in FIG. 3, the upper part of the coil 3b is attached to the inside of the upper part of each wall 3f with a bracket 3g made of an insulating material. A plurality of workpiece support stands 3h are erected diagonally upward inside the middle part of each wall body 3f, and each workpiece support stand 3h has a lower part of a coil 3b made of an insulating material, as shown in FIG. It is attached with bracket 3i. The upper and lower parts of these coils 3b are horizontally offset, and when the workpiece W is placed on the workpiece support stand 3h, the coils 3b
The upper part of is released upward and outward from the peripheral edge of the workpiece W,
The lower portion of the coil 3b is separated from the peripheral edge of the workpiece W downwardly and inwardly. Specifically, when the line control device 8 stops the lifton cylinder 2b at the lower limit position and outputs a heat treatment signal to the high frequency power source 3a of the heat treatment equipment W3, the high frequency power source 3a supplies a high frequency current to the coil 3b through which cooling water is flowing. for a predetermined period of time. Then, the peripheral edge of the workpiece W placed on the workpiece support table 3h is induction heated by the coil 3b and annealed. After the annealing process is completed, that is, after the high-frequency current supply time to the coil 3b has elapsed, the line control device 8 drives the lift nolinder 2b to extend from the lower limit position. Note that the amount of water consumed may be reduced by controlling the cooling water to flow for a slightly longer time than the high-frequency current is supplied to the coil 3b and stopping the water after the annealing process.

The third conveyor device 4 transports the work W that has been annealed from the heat treatment device 3 side to the unloading position T on the pallet 9 side. It is provided with a pair of left and right conveyor belts 4& arranged at a height. Each of the conveyor belts 4a includes a drive pulley 4d and a driven pulley attached to the front and rear ends of the left and right side frames 4c on the upper part of the device main body 4b, which are placed on the installation floor in front of the second conveyor device 2 in the conveyance direction. The hook is passed across 4e and 4e. Each drive pulley 4d has a left and right side frame 4.
The output shaft of a motor 4g that is attached to a front frame 4f that is horizontally suspended across the end of the plane c and that rotates synchronously is connected thereto. This motor 4g is driven and controlled by a line control device 8. Further, a third work sensor 4h is attached to the upper surface of the front end of at least one of the left and right side frames 4c. This third work sensor 4
h detects that the workpiece W has arrived at the unloading position T of the third conveyor device 4, and when the workpiece detection signal is output to the line control device 8, the line control device 8 Motors 2h and 4g of the third conveyor device 2.4 are stopped. In other words, the work W transferred from the conveyor belt 2a of the second conveyor device 2 at the ascending limit position to the conveyor belt 4a of the third conveyor device 4 is transferred to the third conveyor belt 4a.
Arriving at the unloading position T of the conveyor device 4,
When the workpiece detection signal from the third workpiece sensor 4h is input to the line control device 8, the workpiece W is stopped at the unloading position T of the third conveyor device 8.

The infrared camera 5 detects the unloading position T based on an instruction output from the image processing device 6 when the workpiece W is transported to the unloading position T of the third conveyor device 4 and the second conveyor device 4 stops. The device captures an image of infrared rays generated from the peripheral edge of a workpiece W that is stationary, and outputs the image signal to an image processing device 6,
For example, it is attached to a frame 5a placed on the installation floor so as not to interfere with the third conveyor device 4, hand robot 7, etc., and images the entire workpiece W above the unloading position T of the second conveyor device 4. spaced apart from each other at a necessary and sufficient distance.

When the workpiece W is conveyed to the unloading position T of the second conveyor device 4 and the second conveyor device 4 stops, the image processing device 6 first performs step 101 in FIG.
As shown in FIG. 2, an instruction including a workpiece identification signal is received from the robot controller 70 of the hand robot 7. Then, as shown in step 102 of FIG.
While outputting a synchronization signal to
As shown at 109, the image signal from the infrared camera 5 is subjected to image processing. In other words, in step 104, step 103
Contour processing is performed using the image signal received in step 105 (see FIG. 5(a)), and in step 105, statistical processing such as maximum, minimum, average standard deviation, etc. is performed to determine a threshold value δ, and step 106
Then, perform quantization processing such as binarization, and proceed to step 107.
In step 108, the contour part is smoothed, and in step 108, the values inside the contour are made constant to create an infrared pattern P1. In step 109, the center of gravity position and inclination of the infrared pattern P are calculated (see Fig. 5(b)). , step 110
Now, the coordinates of the infrared pattern P are corrected so that the above-mentioned inclination becomes zero (see FIG. 5(c)). Next, step I
In II, a basic pattern P corresponding to the work identification signal is selected from a group of basic patterns stored (set) in the image memory in the image processing device 6 in advance. Describe. Then, in steps 112 and 113, the infrared pattern P subjected to the image processing is converted into the basic pattern P drawn as described above.

The position and orientation of the workpiece W, which is stationary at the unloading position T, is recognized by comparing it with the unloading position T. Thereafter, in step 114, the workpiece position signal and workpiece orientation signal as the recognition results are output to the controller 70 of the hand robot 7. In other words, the X-Y coordinate position data X of the hand robot 7 is determined by the workpiece position signal and the workpiece orientation signal.
Output Y and rotation angle data θ.

The hand robot 7 includes a robot controller 70, a robot main body 71 whose drive is controlled by the robot controller 70, and a hand unit 72 whose drive is controlled by the robot controller 70. This hand unit 72 includes a base plate 72a attached to an arm 71a of the robot body 71. A rectangular frame 72b is attached to the lower surface of the base plate 72. A pair of right and left clampers 72d are rotatably attached to the front and rear frame portions 72c of the frame 72b. In other words, the vertical middle part of the front and rear clampers 72d is the bracket 7 provided on the outside of the front and rear frame parts 72c.
2e with a pin 72f. Front and rear clamper 72
A hook portion 72g is formed inwardly at the lower end that protrudes below the frame 72b. A connecting rod 72h is horizontally suspended across the upper end of the front and rear clamper 72d that protrudes above the frame 72b.

An operating rod of a clamp cylinder 72i rotatably attached to the lower surface of the base plate 72λ is rotatably connected to a left-right intermediate portion of the connecting rod 72h. Further, a pub door 2j is attached to the lower surface of the base plate 72a around the clamp cylinder 72i in the left and right direction in a state where it is suspended by a spring 72. This pad 72j is the hook of the front and rear clampers 72d*
When the workpiece W is supported (grasped) on the workpiece 72g, the spring 72k contacts the upper surface of the workpiece W in a compressed state. When the robot controller 70 receives the instruction including the workpiece identification signal from the line control device 8, the robot controller 70
While outputting a workpiece identification signal to the image processing device 6 as shown in steps 120 and 121 of the figure, when receiving a workpiece position signal and a workpiece orientation signal from the image processing device 6 as shown in step 122 of FIG. , robot body 71
The arm 71a and the hand unit 72 are driven, and the workpiece W, which is stationary at the unloading position T, is gripped by the hand unit 72 and loaded onto the palibutton 9. That is, when the robot controller 70 receives the workpiece position signal and the workpiece orientation signal, the robot controller 70 receives the arm 7 of the robot main body 71.
By aligning the vertical axis of 1λ with the center of the workpiece W stationary at the unloading position T, the gripping position of the hand unit 72 is aligned with the workpiece W as shown in step 123 in FIG. 4, and the arm 71a The front and rear clampers 72d of the hand unit 72 are positioned on the front and rear edge sides of the workpiece W by rotating horizontally about its vertical axis, and the hand unit 72 is aligned with the direction of the workpiece W. Lower the arm 71a with the front and rear clampers 72d of the unit 72 open,
The arm 7Ia stops descending when the hook portion 72g at the tip of the front and rear clampers 72d is positioned below the workpiece W, and at this stop position, after closing the front and rear clampers 72d as shown in step 124 in FIG. By raising 71a, the workpiece W is transferred to the hand unit 72.
Grip with.

Next, as shown in step 125 in FIG. 4, while holding the work W, the arm 71a is raised to move the work W to the third position.
The arm 71 moves horizontally toward the pallet 9 side upwardly away from the conveyor device 4, and stops when it reaches directly above the pallet 9.
a and the hand unit 72, and then move the arm 7.
1a is lowered, and when the workpiece W reaches near the loading position of the pallet 9, the arm 71a is stopped, and the front and rear clampers 72d of the hand unit 72 are opened to place the workpiece W on the pallet 9.

According to the above embodiment structure, first, the workpiece W discharged from the press machine is transferred from the first conveyor device l to the second conveyor device 2 at the upper limit position, and then the workpiece W is lowered by the second conveyor device 2. When the workpiece W is housed in the heat treatment device 3 and fixed on the workpiece support stand 3h, the peripheral edge of the workpiece W is subjected to an annealing process as a heat treatment in the heat treatment device 3.

Next, the annealed workpiece W is moved above the heat treatment apparatus 3 by the rise of the second conveyor apparatus 2, and is transferred from the second conveyor apparatus 2 to the third conveyor apparatus 4.

Then, when the workpiece W is transported to the unloading position T of the third conveyor device 4, the 23rd conveyor device 2
．． 4 stops, and at this unloading position T, the infrared camera 5 images the infrared rays generated from the peripheral portion of the workpiece W. Then, the image processing device 6 generates an infrared pattern P,
is image-processed, and a predetermined basic pattern P corresponding to the workpiece W is selected from a group of basic patterns set in advance.
is extracted from the image memory, and the above-mentioned image-processed infrared pattern P1 is compared with the above-extracted basic pattern Pa,
The position and orientation of the workpiece W that is stationary at the unloading position T is recognized.

In accordance with this recognition result, the gripping position and orientation of the hand unit 72 of the hand robot 70 with respect to the workpiece W are controlled.

Then, the hand unit 72 moves toward the pallet 9 while holding the workpiece W stopped at the unloading position T of the third conveyor device 4. and hand unit 7
2 reaches the work discharge position of the pallet 9, the works W are released and loaded onto the pallet 9 one after another.

Effects of the Invention As described above, according to the present invention, by heat-treating the work while the work is being conveyed from the press machine to the unloading position of the conveyor device, the strain caused in the work by press processing can be reduced. It can be removed and the quality of the workpiece can be improved. Moreover, since the infrared pattern is image-processed using the infrared rays emitted from the workpiece during the heat treatment, the position and orientation of the workpiece stopped at the unloading position can be reliably determined, even if the workpiece has a curved surface. can be recognized. Furthermore, since the gripping position and orientation of the hand unit with respect to the workpiece are controlled in accordance with the recognition result, the hand unit can suitably grip the workpiece stopped at the unloading position and load it onto the pallet.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the entire system used in the present invention, FIG. 2 is an explanatory diagram of the operation of the same embodiment, and FIG. 3 is a sectional view taken along the line ■-■ shown in FIG. FIG. 4 is a flowchart of the image processing device and hand robot of the same embodiment, and FIG. 5 is an infrared pattern diagram of a workpiece of the same embodiment. l...first conveyor device (conveyor device), 2...
Second conveyor device M (conveyor device), 3... heat treatment device, 4... third conveyor device (conveyor device), 5...
- Infrared camera, 6... Image processing device, 7... Hand robot, 8... Line control device, 9... Valet. Figure 5 (0) (b) (C)

Claims (1)

[Claims] (1) The workpiece discharged from the press machine is conveyed toward the pallet by a conveyor device, and when the workpiece is conveyed to the unloading position of the conveyor device, the conveyor device is stopped, and the conveyor device is stopped at the unloading position of this conveyor device. In a workpiece loading method in which a stopped workpiece is gripped by a hand unit of a hand robot and loaded onto a pallet, the workpiece is transferred from the press machine to the unloading position of the conveyor device after heat treatment is applied to the workpiece. , image-process the infrared pattern of this workpiece,
A workpiece loading method characterized by comparing this image-processed infrared pattern with a basic pattern to recognize the position and orientation of the workpiece, and controlling the gripping position and orientation of the hand unit with respect to the workpiece according to the recognition result. .