JPH0133390B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a workpiece positioning device, and more specifically, an industrial robot (automatic assembly system) that automatically assembles parts such as windows and glass onto a workpiece, that is, a car body, on an automobile assembly line. machine)
On the other hand, the present invention relates to a workpiece positioning device that is applied when stopping a vehicle body in a fixed position.

In this specification, "back and forth" refers to the direction of conveyance of the workpiece, and "front" refers to the direction of conveyance of the workpiece.
Rear means the opposite direction, and left and right means both sides of the front.

Traditionally, for example, in the automobile manufacturing process, simple tasks such as specific welding and bolt tightening tasks have been automated using industrial robots installed on the side of the assembly line. -Glass is difficult to assemble, so automation using industrial robots has not yet been carried out. However, if it is possible to stop the car body conveyed by a conveyor on the assembly line at an accurate position relative to the robot, then such a window system can be used.
Glass assembly work can also be performed automatically by robots, and there has been a strong desire in the industry for a device that can accurately position workpieces such as automobile bodies.

The present invention is intended to meet the above-mentioned needs, and is to provide a workpiece that can constantly and reliably align the relative position of an automobile body with respect to an industrial robot on an automobile assembly line as mentioned above. The object of the present invention is to provide a positioning device.

In order to achieve the above-mentioned object, the present invention first provides a first aspect in which a left-right movable table is provided on a base so as to be movable left and right, a left-right movable table drive mechanism that operates the left-right movable table, and a pivot shaft on the left-right movable table. a workpiece positioning device equipped with a rotary table rotatably mounted on the rotary table and having a workpiece holder, and a rotary table drive mechanism for operating the rotary table; It is equipped with a pair of scales that automatically measure the distance from two reference points to the workpiece placed on the position adjustment device, and the difference in the measured distances measured by these scales is calculated. Based on the length measuring device that calculates and converts this into a signal, and the signal representing the difference between the measured distances sent from the length measuring device, this is compared with the set value to determine the necessary correction angle for the workpiece. and a control device that determines left and right correction distances, converts these into adjustment signals, and operates the rotary table drive mechanism and the left and right moving table drive mechanism using the adjustment signals. The gist is the device.

According to the first invention, since a workpiece such as an automobile body can be positioned at a fixed distance from a reference point, an industrial robot placed at a fixed distance from the same reference point and a workpiece after positioning can be The distance between the workpiece and the workpiece is always constant, so that the industrial robot can automatically perform various operations on the workpiece.

In the first invention, after correcting the angle and the horizontal distance of the workpiece, the workpiece is moved forward at a constant speed, and the industrial robot is synchronized and moved in the same direction. By moving them and relatively matching their front and rear positions, various operations on the workpiece may be automatically performed, for example, the task of assembling a window glass to the body of an automobile.

Next, a second invention of the present invention further develops the first invention and also positions the workpiece in the front-back direction.

That is, the second invention provides a back-and-forth moving table provided on a base so as to be freely movable back and forth, a back-and-forth moving table drive mechanism for operating the same, a left-right moving table provided on the back-and-forth moving table so as to be movable left and right, and a system for operating the same. A workpiece position adjustment device comprising: a left-right moving table drive mechanism, a rotary table rotatably mounted on the left-right moving table by a pivot shaft and having a workpiece receiver on the upper surface; A pair of scales are disposed on one side of the positioning device at the location where the object is to be positioned, and are equipped with a pair of scales that automatically measure the distance from two reference points to the workpiece placed on the positioning device. ,
A first length measuring device that calculates the difference between the measurement distances measured by these scales and converts it into a signal, and a first length measuring device that is placed above or to the side of the positioning device at the location where the workpiece is to be positioned. The machine is equipped with a scale that automatically measures the distance in the longitudinal direction from one reference point to the workpiece placed on the position adjustment device, and converts the measured distance measured by this scale into a signal. a second length measuring device;
Based on the signal representing the difference in measured distance sent from the first length measuring device, this is compared with the set value to determine the necessary correction angle and left and right correction distance for the workpiece, and these are converted into adjustment signals. Then, using this adjustment signal, the rotary table drive mechanism and the left and right moving table drive mechanism are operated, and based on the signal representing the measured distance sent from the second length measuring device, this is compared with the set value, Workpiece positioning comprising a control device that determines a necessary longitudinal correction distance for the workpiece, converts it into an adjustment signal, and operates the longitudinal movement table drive mechanism based on the adjustment signal. The gist is the device.

According to the second aspect of the invention, the relative position between a workpiece such as an automobile body and an industrial robot placed on the floor can always be kept constant and reliably aligned, thereby allowing the industrial robot to perform various tasks. This has the effect of reliably automating the work, especially the work of assembling windows and glass to the vehicle body.

Further, a third invention of the present invention is a further development of the second invention, in which the workpiece is also positioned while being lifted to a predetermined height.

That is, in this third invention, an elevating table and an elevating table driving mechanism are provided on the front-back movable table of the position adjusting device in the second invention, and the workpiece is moved to a predetermined height by the operation of the elevating table driving mechanism. According to the third invention, for example, in an automobile assembly line, a car body (workpiece) conveyed by a slat conveyor is separated from the conveyor. Even if the height of the workpiece varies depending on the type of vehicle, the height of the workpiece can be adjusted accordingly, making it easy to perform various tasks. This has the effect that automation can be achieved more completely.

Further, according to the first to third aspects of the present invention,
A left/right moving table and a rotary table are installed together on the base of the workpiece position adjustment device, or these and a front/rear moving table are installed together, and furthermore, an elevating table is installed in addition to these. Because of this, the workpiece positioning device is very compact, so it can be placed in the middle of a double-slat conveyor in an automobile assembly line, requiring very little installation space and Since the first and second length measuring instruments are placed to the side and above the position of the workpiece, the workpiece positioning operation can be carried out efficiently without any hesitation. It is something that plays.

Next, embodiments of the present invention will be described in detail based on the drawings. In this embodiment, the present invention is applied to the case where parts such as windows and glass are attached to the body of an automobile in an assembly line of an automobile manufacturing process.

FIG. 1 schematically shows the process of positioning an automobile body (workpiece) 1 using the apparatus of the present invention. Referring to FIG. 1, the car body 1
is lifted to a predetermined height from a slat conveyor at a location where it is to be positioned, that is, in front of the location where an industrial robot (not shown) is installed (see A in the figure), and then transferred to a location where the vehicle body 1 is to be positioned; There, it is stopped (Figure B). In this stopped state, first the angle of the vehicle body 1 is corrected (Figure C), then the distance in the left-right direction is corrected (D in the figure), and finally the distance in the longitudinal direction is corrected (E in the figure). Therefore, the relative position between the vehicle body 1 and the industrial robot is kept constant. After the robot automatically assembles, for example, a window glass, the vehicle body 1 is moved forward a required distance and placed on a slat conveyor (FIG. 1).

2 to 4 show the entire positioning device for a vehicle body 1 on an automobile assembly line.

In the figure, 2 is a floor, 3 is a pair of left and right slat conveyors, and 4 is a positioning device for the vehicle body 1, which is installed in a pit 5 between the two slat conveyors 3.

In the vehicle body positioning device 4, A is a position adjustment device which can be moved back and forth within the pit 5. 6 is a base of the position adjustment device A, and 7 is four rollers attached to the base 6, which roll on a pair of rails 8 installed in the pit 5. Reference numeral 9 denotes an endless drive chain for operating the base 6 with rollers, which is connected to the lower end of the base 6 and moves the base 6, and therefore the entire position adjustment device A, back and forth by the operation of the servo motor 10. It is something that forces you to do something. B is a first length measuring device installed on the floor 2 outside the left slat conveyor 3 in the standby area of the industrial robot. It is equipped with a pair of front and rear scales 11 and 12 that are expandable and retractable in the left-right direction and measure the distance to the left and right. C is a second measuring device that is also installed at a predetermined height above the assembly line in the standby area for industrial robots.
5. A scale 1 that is attached to the tip of the horizontal arm 16 at the upper end and that can be expanded and contracted in the front-rear direction and measures the distance from the reference point to the front end of the top wall of the vehicle body 1.
It has 3. Furthermore, these scales 11,
High precision scales with magnetic graduations are used as 12 and 13.

D is also in pit 5 at the robot standby area.
This is a stop device installed on the machine base 17 in the machine, and is used to firmly stop the base 6 with rollers of the position adjustment device A, and after this stop, the positioning operation of the vehicle body 1 on the position adjustment device A is performed. will be carried out.

5 to 13 show details of the position adjustment device A.

Here, in FIGS. 5 and 6 showing the whole of the device A, the position adjustment device A is a rectangular back and forth moving table 21 which is provided on a rectangular base 6 having rollers 7 so as to be movable back and forth. , a back-and-forth moving table drive mechanism 22 that operates this, a rectangular lifting table 23 that is provided on the back-and-forth moving table 21 so as to be able to rise and fall freely, a lifting table drive mechanism 24 that operates this, and a lifting table 23.
A rectangular left-right moving table 25 is provided on the top so that it can be moved left and right, a left-right moving table drive mechanism 26 that operates the left-right moving table 25 is rotatably mounted on the left-right moving table 25 by a pivot shaft 29, and a vehicle body support 30 is mounted on the upper surface. It is provided with a rectangular rotating table 27 and a rotating table driving mechanism 28 that operates the rotating table.

Turntable 2 provided at the upper end of position adjustment device A
7 and the details of the rotational drive mechanism 28 are shown in FIG.

In the figure, four vehicle body supports 30 for supporting the vehicle body 1 are attached to the four corners of a rotary table 27 by shafts 31 so as to be horizontally movable. Reference numeral 32 denotes a lever provided coaxially with each vehicle body receiver 30, and the end of this lever is connected to the tip of the piston rod 34 of the air cylinder 33 by a pin. By retracting the piston rods 34, the body holders 30 protrude outside the rotating table 27 and the car body 1 is received therein, and when they are not needed, by protruding the piston rods 34, the body holders 30 are moved inside the rotating table 28. It is designed so that it can be accommodated in

Details of the rotary table drive mechanism 28 are shown in FIGS. 7 and 8. In the figure, reference numeral 35 denotes a mounting plate provided in an overhanging manner at the front end of the left-right moving table 25;
A rotary table drive mechanism 28 is fixed to the upper surface of this. In this rotary table drive mechanism 28, 36 is a servo motor, 37 is a horizontal threaded rod rotatably attached to the servo motor 36 via a coupling, and the tip of this rod is erected on the mounting plate 35. It is rotatably supported on a vertical bracket 38. Reference numeral 39 denotes a substantially box-shaped sliding body that is attached to the middle part of the length of the threaded rod 37 via a female thread so as to be movable left and right, and a pair of front and rear linear ball bearings 40 are attached to the lower end of this sliding body. . These bearings 40 are guided by a pair of guide bars 41 fixed to the mounting plate 35. In addition, the female screw built into the sliding body 39,
A ball screw is used for the threaded rod 37. A link 42 has one end attached to the upper end of the sliding body 39 with a pin, and the other end is connected by a pin to a bracket 43 provided at the front end of the rotary table 27 in a forward-protruding manner. 44 is rotating table 2
Four vertical rollers are attached to the four corners of the lower left-right moving table 25, and the four corners of the lower surface of the rotary table 27 are supported by these vertical rollers 44.

The rotating table 27 is a sliding body with a built-in female thread that engages with a threaded rod 37 that rotates in a predetermined direction when a servo motor 36 is operated based on an adjustment signal transmitted from a control device to be described later. 39 is made to slide in either the left or right direction along the guide bar 41, and this movement is transmitted to the rotary table 27 via the link 42 and the bracket 43, and the rotary table 27 rotates clockwise or clockwise around the pivot shaft 29. It is designed so that it can be rotated by a required angle in either direction counterclockwise.

Details of the left-right moving table 25 are shown in FIGS. 8 and 9. In the figure, a pivot shaft 29 of a rotating table 27 is vertically attached to the center of the upper surface of a left-right moving table 25. 45 are attached to the four corners of the lower surface of the left and right moving table 25 in a downwardly projecting manner and in the left and right direction.
These protrusions 45 are guided by guides 46 made of linear ball bearings attached to the four corners of the upper surface of the elevator platform 23. Reference numeral 47 denotes a horizontal bracket provided at the rear end of the left-right moving table 25 in a rearwardly projecting manner.

Details of the left and right moving table drive mechanism 26 are shown in FIGS. 8, 10, and 11. In the figure, reference numeral 48 denotes a mounting plate provided in an overhanging manner at the rear end of the lifting table 23, and the left-right moving table drive mechanism 26 is fixed to the upper surface of this mounting plate. This drive mechanism 26 is equipped with a servo motor 36 and has substantially the same configuration as the rotary table drive mechanism 28 described above, and accordingly, the same parts are given the same reference numerals in the drawings. The link 49 connected to the horizontal bracket 47 by a pin is slightly shorter than the link 42 described above.

The left and right moving table 25 is operated by a servo motor 36 based on an adjustment signal transmitted from a control device to be described later.
is activated, the rotary table 27 is moved a required distance along the guide 46 in either the left or right direction.

Details of the lifting table 23 and the lifting table drive mechanism 24 are shown in FIGS. 10 and 11. In the figure, the tip of a piston rod 18 of a lifting table drive mechanism 24 consisting of a hydraulic cylinder is attached to the center of the lifting table 23 via a fixing plate 50. The hydraulic cylinder 24 is attached to the center of the lower back-and-forth movable table 21 via a fixing plate 51. Reference numeral 52 indicates fixed plates 53 at both front and rear ends of the lifting platform 23.
The lower halves of these slide bars are fitted into cylindrical guides 54 made of linear ball bearings attached to both the front and rear ends of the front and rear moving table 21. ing. By the operation of the hydraulic cylinder 24, the elevating table 23, the left-right moving table 25 above it, and the rotary table 27 are raised and lowered together to a required height.

Back and forth moving table 21 and back and forth moving table drive mechanism 22
Details are shown in FIGS. 5 and 6 as well as in FIGS. 11 and 12. In the figure, reference numeral 55 denotes linear ball bearings attached to the four corners of the lower surface of the back-and-forth movable table 21, and these are guided by a guide bar 56 provided on the upper surface of the base 6 in the front-rear direction. Reference numeral 57 denotes a mounting plate fixed to the front left side of the longitudinally movable table 21, and the longitudinally movable table driving mechanism 22 is attached to the lower surface of this plate. In this drive mechanism 22, 58 is a servo motor fixed to the lower front part of the mounting plate 57, and 59 is a threaded rod attached to the servo motor 58. It is rotatably supported by a bracket 60. Reference numeral 61 denotes a substantially box-shaped fixing member that is fitted onto the intermediate portion of the length of the threaded rod 59 via a female thread, and is attached to the base 6 via a bracket.

In the fore-and-aft movable table 21, the servo motor 58 is operated based on an adjustment signal transmitted from a control device to be described later, so that the threaded rod 58 is operated.
9 is rotated, but since the female thread that engages with this is built into the fixing member 61 attached to the base 6, the threaded rod 59 can be rotated in either the front or rear direction by the fixing member 61. As a result, the servo motor 58 further moves the back-and-forth moving table 21 along the guide bar 56 in either the front or rear direction, and the lifting table 23, the left-right moving table 25, and the rotating table 27 on the upper part thereof. The robot is moved the required distance.

Details of the base 6 with rollers are shown in FIGS. 5 and 6,
and shown in FIG. In the same figure,
Reference numeral 62 denotes box-shaped roller mounting members fixed to the four corners of the lower surface of the base 6 and opening downward; each mounting member 62
A vertical roller 7 is fixed to the shaft. Reference numeral 63 denotes a pair of front and rear roller mounting members 62 on the left side edge of the base 6.
A pair of horizontal rollers 63 are attached to the left and right sides of the rail 8 via brackets, and each pair of horizontal rollers 63 sandwich the left rail 8 from both the left and right sides and roll along both sides of the left rail 8. A connecting piece 64 is fixed to a portion near the left edge of the lower surface of the base 6, and the lower end of this connecting piece is connected to a link of the endless drive chain 9. 65 is a pair of upper and lower guide rails that guide the drive chain 9. The endless drive chain 9 is rotated by a predetermined distance by the operation of the servo motor 10, so that the base 6 with rollers is moved forward or backward by a predetermined distance. Reference numeral 66 denotes a shock absorber provided at the center of the lower surface, and a contact piece 67 is provided at the front end of this shock absorber, which is always urged forward by a spring force. Reference numeral 68 denotes a cable chain, the tip of which is attached to the front end of the back-and-forth moving table 21 via a bracket 69.

Details of the stop device D are shown in FIGS. 14 and 15. In the same figure, 70 is a pair of parallel mounting frames fixed on the machine base 17 at the center of the pit 5, and 71 is a pair of parallel mounting frames 71 that are swingably mounted at the center of the length of the mounting frame 70. It is an L-shaped stop piece, the rear end of which is fixed to the mounting frame 70 by a shaft 72, and a backing plate 73 that comes into contact with the contact piece 67 of the shock absorber 66 is provided on the rear surface of the swinging end. A small roller 74 is fixed to the front side of the backing plate 73. Reference numeral 75 denotes a support lever in the shape of a dogleg when viewed from the side, which is rotatably attached to the mounting frame 70 on the front side of the stop piece 71. The central bent part of this lever is fixed to the mounting frame 70 by a shaft 76, and A roller 74 of the stop piece 71 is placed on one end, and the swinging end of the stop piece 71 is supported by this support lever 75. Reference numeral 77 denotes a base stop air cylinder that is swingably and approximately horizontally attached to the tip of the mounting frame 70, and the other end of the support lever 75 is connected with a pin to the tip of this backward piston rod 78. has been done. A lock piece 79 is rotatably attached to the mounting frame 70 on the rear side of the stop piece 71, and its approximately central portion is fixed to the mounting frame 70 by a shaft 80, and its upper end is attached to the shock absorber 66. It is designed to hold down the rear of the Reference numeral 81 denotes a locking air cylinder that is swingably and approximately horizontally attached to the rear end of the mounting frame 70, and the lower end of the locking piece 79 is connected with a pin to the tip of the forward-facing piston rod 82. It is being

In the above-mentioned stopping device D, when the position adjusting device A loaded with the vehicle body 1 is transferred, the stopping piece 71 is positioned at the upper limit by the operation of the stopping air cylinder 77, and the locking air cylinder 81 By this operation, the upper end of the lock piece 79 is positioned at the lower limit. A contact piece 6 of a buffer 66 provided at the lower end of the base 6 with rollers
7 hits the backing plate 73 of the stop piece 71, and the base 6
is loosely stopped by the action of the spring force applied to the contact piece 67. Thereafter, due to the operation of the locking air cylinder 81, the upper end of the locking piece 79 is strongly pressed against the rear surface of the shock absorber 66, and as a result, the backing plate 73 pushes the contact piece 67 against the spring force into the shock absorber 66.
6, the shock absorber 66 is sandwiched between the backing plate 73 and the lock piece 79, and the base 6 with rollers is firmly stopped.

Details of the first length measuring device B are shown in FIGS. 3 and 4, and FIGS. 16 to 18. First, in FIG. 3, the first length measuring device B is constituted by a length measuring system including front and rear length measuring devices 83 and 84 arranged parallel to each other in the left-right direction with a predetermined spacing between them. These front and rear length measuring devices 83, 8
4 have almost the same configuration. 16 to 18 showing details of these length measuring devices 83 and 84.
In the figure, 85 is a long scale cover of the front and rear length measuring devices 83, 84, and scales 11, 12 having magnetic scales are provided inside this cover. 8
6 is a part attached to the tip of the scales 11 and 12, and 87 is a protrusion attached to the bottom surface of the scale cover 85 in the length direction, which is attached to the mounting base 14.
It is slidably fitted onto a pair of left and right linear ball bearings 88 provided above. 8
Reference numeral 9 denotes a detection head fixed to the mounting base 14, the upper end of which is exposed to the scales 11 and 12, and detects the amount of passage of the magnetic scale due to the movement of the scales 11 and 12. , which measures distance. 90 is a scale driving air cylinder, and 91 is its piston rod, which protrudes from the right end of the cylinder 90, and its tip is connected to the tip of the scale cover 85 via a bracket 92. The left end of the air cylinder 90 is connected to a connecting piece 93 with a pin. Reference numeral 94 denotes a mounting rod connected to the connecting piece 93 so as to extend to the left, and this is loosely inserted into a through hole of a fixed bracket 95 erected on the length measuring instrument mount 14. A retaining nut 96 is screwed to the tip of the mounting rod 94 that extends to the left. A coil spring 97 is fitted over the mounting rod 94 between the connecting piece 93 and the fixed bracket 95, and its elastic force constantly urges the connecting piece 93 and the scale driving air cylinder 90 to the right. ing. 98 is a limit switch provided at the left end of the scale cover 85, and 99,100 is a pair of limit switches provided at predetermined locations on the mounting base 14.These switches 99,100
The contactor is adapted to contact the hit point 98. Among these switches 99, 100, one stops the operation of the cylinder 90 when the scales 11, 12 are retracted to the minimum extent, and the other stops the operation of the cylinder 90 when the scales 11, 12 are extended to the maximum extent.
This is to stop the operation of the scale 11,1.
2 can measure distance within this range. 10
1 is a contact provided integrally with the connecting piece 93, 102
A limit switch for adjusting the scale measurement pressure is provided on the mount 14 near the connecting piece 93, and its contact is in contact with the abutment 101 of the connecting piece 93.

In the first length measuring device B, the front and rear length measuring devices 8
The scale cover 85 and the scales 11 and 12 integral therewith are made to protrude by the operation of the scale driving air cylinders 90 of 3 and 84,
Abutments 86 at the tips of the scales 11 and 12 are brought into contact with the straight portions of the lower edge of the vehicle body 1 placed on the position adjustment device A, respectively. At this time, even if the hit 86 contacts the vehicle body 1, the cylinder 90 does not stop immediately and tries to make its piston rod 91 protrude further, but the left end of the cylinder 90 is pushed by the coil spring 97. Therefore, due to the protrusion of the piston rod 91, the cylinder 9 is relatively
0 retreats to the left against the elastic force of the coil spring 97. As a result, the hit 101 pushes down the contact of the limit switch 102 by the required angle, and the operation of the cylinder 90 is stopped, and the scale 11,
12 is subjected to a constant measurement pressure by the coil spring 97. The moving distances of these scales 11 and 12 are automatically read by the reference points set on the detection head 89, and the distance from the two reference points to a predetermined portion of the vehicle body 1 is automatically measured.

Details of the second length measuring device C are shown in FIGS. 19 to 21. First, in FIG. 19, reference numeral 103 denotes a swingable length measuring device mounting member attached to the tip of the arm 16 by a shaft 104, and a second length measuring device C is provided at the front end of this member. 105 is a rising member provided at the tip of the arm 16;
Reference numeral 6 denotes an air cylinder with a lock for lifting and lowering the length measuring device, which is swingably and hangingly attached to the upper end of the air cylinder. It is connected to the upper front end of member 103. This air
By the operation of the cylinder 105, the mounting member 103 and the second length measuring device C integrated therewith are lifted obliquely to a required height or held in a horizontal state.
Distance measurement is performed when the second length measuring device C is in a horizontal state.

Here, the second length measuring device C has almost the same configuration as the front and rear length measuring devices 83 and 84 of the first length measuring device B, as shown in FIGS. 20 and 21. , the following points are different. That is, the Jyo 108 is provided in a hanging manner at the tip of the scale 13, and when measuring the distance in the longitudinal direction, the Jyo 108 of the scale 13 is first positioned in front of this with respect to the stopped vehicle body 1. The scale 13 is gradually moved backward by the operation of the scale driving air cylinder 90, and when the lower end of the jaw 108 comes into contact with the front end of the top wall of the vehicle body 1, the scale of the scale 13 is automatically read. It's getting old. Further, measurement pressure is applied to the scale 13 in the following manner. That is, the spring receiver 109 is attached to the mounting rod 94 at the rear end of the scale driving cylinder 90 at a position rearward of the fixing member 85, and the mounting rod 9 is attached between the fixed bracket 85 and the spring receiver 109.
4 is fitted with a coil spring 97, so that the scale driving cylinder 90 is always urged rearward by the elastic force of the coil spring 97. When the lower end of the jaw 108 of the scale 13 comes into contact with the front end of the top wall of the vehicle body 1, the cylinder 90
The piston rod 91 attempts to retract further, but since the rear end of the cylinder 90 is always urged rearward by the coil spring 97, the retraction of the piston rod 91 causes the cylinder 90 to become relatively It moves slightly forward against the elastic force of the coil spring 97. Along with this, the contact 110 provided on the spring receiver 109 pushes down the contact of the limit switch 102 by a required angle, thereby stopping the operation of the cylinder 90, and the scale 13 is set to a certain measurement level by the coil spring 97. It is something that can be put under pressure.

The other points of this second length measuring device C are substantially the same in configuration as the front and rear length measuring devices 83 and 84, so corresponding parts in the drawings are given the same reference numerals.

Next, the operation of the positioning device 4 will be explained.

When the vehicle body 1 is transported by the double slat conveyor 3 to the location where it should be positioned, that is, in front of the installation location of the industrial robot (Fig. 2 A), a position adjustment device is placed between the slat conveyors 3. A is waiting (solid line area in Figure 2).
Therefore, by operating the hydraulic cylinder 24, the lifting platform 2
The left and right moving table 25 and the rotary table 27 above the rotary table 3 are raised, and the car body 1 is lifted to a predetermined height by the four car body holders 30 of the rotary table 27, and the car body 1 is separated by the slat conveyor 3. Then, by the operation of the endless drive chain 9, the roller-equipped base 6 of the position adjustment device A on which the vehicle body 1 is placed is transferred to the position where positioning is to be performed, and there, the roller-equipped base 6 is firmly stopped by the action of the above-mentioned stopping device D. urge In this state, the vehicle body 1 is measured from the two reference points using the first length measuring device B placed on the left side of the position adjustment device A.
The difference between the two measured distances is calculated, and this is converted into a signal and sent to a control device (not shown). Experimentally set various distances from the point to the vehicle body 1, find the relationship between the difference between the two distances, the necessary correction angle of the vehicle body 1, and the left and right correction distance, and store these values. Then, this control device compares the difference in the measured distance from the first length measuring device B with the difference in the preset distance, determines the necessary correction angle and left and right correction distance for the vehicle body 1, and adjusts them. Convert to signal,
Using these adjustment signals, the rotary table 27 is rotated by a required angle, and the left/right moving table 25 is moved a required distance. The distance in the longitudinal direction from the reference point to the vehicle body 1 is measured, and the obtained measured distance is converted into a signal and sent to the control device. We experimentally set various distances in the longitudinal direction and the required vehicle body 1 for this distance.
The relationship between the longitudinal and longitudinal correction distances is determined, these values are stored, and the control device compares the measured distance from the second length measuring device C with a preset distance, and then The vehicle body 1 is positioned by determining a necessary longitudinal correction distance, converting this into an adjustment signal, and moving the longitudinal movable table 21 a required distance using this adjustment signal. As a result, the relative position between the vehicle body 1 and the industrial robot becomes constant. After the robot automatically assembles, for example, a window glass, the vehicle body 1 is moved forward a required distance and placed on the slat conveyor 3 (FIG. 2).

In addition, in the above embodiment, an example was shown in which the present invention was applied to the case of attaching parts such as a window glass to the car body 1 of an automobile, but the present invention is not limited to this, and the present invention can be applied to various devices, machines, and devices. Applicable to product assembly lines. In addition, in the example,
Although the base 6 of the position adjustment device A is configured to be movable back and forth, the present invention is not limited to this. For example, the base 6 may be fixed at a location where the workpiece 1 is to be positioned, and other conveyance means may be used. After placing the workpiece 1 on the position adjustment device A and positioning it, necessary parts are assembled, and after assembly, the workpiece 1 is carried away from the position adjustment device A by another conveying means. You may also do so. Alternatively, the entire positioning device 4 for the workpiece 1 and the industrial robot may be mounted together, for example on a slat conveyor, and the workpiece 1
In some cases, the positioning is performed on a conveyor. Note that the drive means for the positioning device 4 is not limited to the one shown in the drawings, and other drive means may of course be used. In addition, as the first length measuring device B, the workpiece 1
Depending on the type of scale, three or more scales may be used to measure the distance; in this case, two scales may be used as a set, and the difference between the measured distances of each set may be determined. Note that the scale is not limited to the one shown in the drawings, and various scales may be used.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic block diagram of the workpiece positioning process, and FIG.
The figure is a side view of the positioning device, FIG. 3 is a plan view of the same,
Fig. 4 is a rear view of the same, Fig. 5 is an enlarged side view of the position adjustment device, Fig. 6 is an enlarged rear view of the same, Fig. 7 is an enlarged plan view of the rotating table, and Fig. 8 is an enlarged plan view of the left and right moving table. An enlarged plan view, Fig. 9 is an enlarged side view of the same part, Fig. 10 is an enlarged plan view of the elevating platform, Fig. 11 is an enlarged side view of the same, and Fig. 12 is an enlarged cross section along the line XII-XII of Fig. 11. Figure 13 is an enlarged plan view of the base part, Figure 14 is an enlarged plan view of the base part.
The figure is an enlarged side view of the stopping device, Fig. 15 is an enlarged plan view of the same, and Fig. 16 is an enlarged side view of the first length measuring device.
Figure 7 is an enlarged plan view of the same, Figure 18 is an enlarged front view of the same,
FIG. 19 is an enlarged side view of the attachment portion of the second length measuring device, FIG. 20 is an enlarged side view of the second length measuring device, and FIG. 21 is an enlarged rear view of the second length measuring device. 1... Vehicle body (workpiece), A... Workpiece position adjustment device, B... First length measuring device, C... Second length measuring device, D
...Stopping device, 2...Floor, 3...Slat conveyor, 4...Positioning device, 6...Base, 7...
Roller, 9... Endless chain, 11, 12, 13...
... Scale, 21 ... Back and forth moving table, 22 ... Back and forth moving table drive mechanism, 23 ... Lifting table, 24 ... Hydraulic cylinder (lifting table drive mechanism), 25 ... Left and right moving table, 26 ... Left and right moving table Drive mechanism, 27... Turntable, 28... Turntable drive mechanism, 29... Pivot, 3
0...Car body support (workpiece support).

Claims (1)

[Scope of Claims] 1. A left-right moving table 25 provided on the base 6 so as to be movable left and right, a left-right moving table drive mechanism 26 that operates the left-right moving table 25, and a left-right moving table drive mechanism 26 rotatably mounted on the left-right moving table 25 by a pivot shaft 29. A workpiece position adjustment device A including a rotary table 27 having a workpiece receiver 30 and a rotary table drive mechanism 28 for operating the rotary table 27, and a workpiece position adjustment device A disposed on one side of the position adjustment device A at a location where the workpiece 1 is to be positioned. position adjustment device A
A pair of scales 11 and 12 are provided to automatically measure the distance from two reference points to the workpiece 1 placed on the workpiece 1. Length measuring device B calculates the difference and converts it into a signal.Based on the signal representing the difference in the measured distance sent from length measuring device B, this is compared with the set value and Determine the necessary correction angle and left/right correction distance, convert these into adjustment signals, and use the adjustment signals to drive the rotating table drive mechanism 28 and the left and right moving table drive mechanism 2.
6 and a control device for operating the workpiece positioning device. 2. A back-and-forth moving table 21 provided on the base 6 so as to be freely movable back and forth, a back-and-forth moving table drive mechanism 22 that operates this, a left-right moving table 25 that is provided on the back-and-forth moving table 21 so as to be able to move left and right, and this is activated. A left-right moving table drive mechanism 26, a pivot 29 on the left-right moving table 25
A workpiece position adjustment device A is provided with a rotary table 27 which is rotatably attached and has a workpiece receiver 30 on its upper surface, and a rotary table drive mechanism 28 that operates the rotary table drive mechanism 28, and a workpiece position adjustment device A at a position where the workpiece 1 is to be positioned. With respect to the workpiece 1 placed on one side of the position adjustment device A and placed on the position adjustment device A,
Equipped with a pair of scales 11 and 12 that automatically measure the distance from two reference points to the workpiece 1,
A first length measuring device B that calculates the difference between the measured distances measured by these scales 11 and 12 and converts it into a signal, and a position adjusting device A that calculates the difference between the measured distances measured by these scales 11 and 12 and converts it into a signal, A scale 13 is provided for automatically measuring the distance from one reference point to the workpiece 1 in the front-rear direction with respect to the workpiece 1 placed above or on the side and placed on the position adjustment device A. Based on the signal representing the difference between the measured distance sent from the second length measuring device C, which converts the measured distance measured by the machine into a signal, and the first length measuring device B, this is compared with the set value, and the workpiece is 1, determine the necessary correction angle and left/right correction distance, convert these into adjustment signals, and use these adjustment signals to drive the rotary table drive mechanism 28 and the left and right moving table drive mechanism 26.
At the same time, based on the signal representing the measured distance sent from the second length measuring device C, this is compared with the set value to determine the necessary longitudinal correction distance for the workpiece 1 and adjust it. and a control device that converts the adjustment signal into a signal and operates the back-and-forth moving table drive mechanism 22 based on the adjustment signal. 3. A back-and-forth moving table 21 provided on the base 6 so as to be freely movable back and forth, a back-and-forth moving table drive mechanism 22 that operates this, an elevating table 23 that is provided on the back-and-forth moving table 21 so as to be movable up and down, and an elevating table that operates this. A drive mechanism 24, a left-right moving table 25 provided on the lifting table 23 so as to be movable left and right, a left-right moving table drive mechanism 26 that operates this, a mechanism rotatably attached to the left-right moving table 25 by a pivot 29 and machined on the upper surface. A workpiece position adjustment device A is provided with a rotary table 27 having an object receiver 30 and a rotary table drive mechanism 28 that operates the rotary table drive mechanism 27, and a workpiece position adjustment device A is arranged on one side of the position adjustment device A at a position where the workpiece 1 is to be positioned. and a pair of scales 11 that automatically measure the distances from two reference points to the workpiece 1, which is held lifted at a predetermined height by the operation of the lifting platform drive mechanism 24 of the position adjustment device A. , 12, which calculates the difference between the measurement distances measured by these scales 11 and 12 and converts it into a signal, and A scale that automatically measures the distance from one reference point to the workpiece 1 in the front-rear direction with respect to the workpiece 1 placed above or to the side of the position adjustment device A and held in a lifted state by the position adjustment device A. This is set based on the signal representing the difference in the measured distance sent from the second length measuring device C, which converts the measured distance measured by the scale 13 into a signal, and the first length measuring device B. compared to the value
The necessary correction angle and left-right correction distance for the workpiece 1 are determined, these are converted into adjustment signals, and the above-mentioned rotary table drive mechanism 28 and left-right movable table drive mechanism 26 are operated by this adjustment signal. 2 Based on the signal representing the measured distance sent from the length measuring device C, this is compared with the set value to determine the necessary longitudinal correction distance for the workpiece 1, and this is converted into an adjustment signal. A workpiece positioning device comprising: a control device that operates the back-and-forth movable table drive mechanism 22 in accordance with an adjustment signal;