JPH0341391B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for automatically assembling vehicle parts, and particularly to a vehicle in which vehicle parts are assembled to predetermined parts of a vehicle body via fasteners such as bolts and nuts. This invention relates to a method and device for automatically assembling parts.

Conventionally, on an automobile assembly line, for example,
The work of assembling the strut assembly (hereinafter referred to as strut) of a strut-type front suspension as a vehicle component was generally performed by a worker. That is, one worker positions and holds the strut by fitting the upper part of the strut into the positioning hole of the vehicle body, and in this state, another worker places a fastener tightening device such as a nut in a predetermined position, and
The task involved tightening nuts onto the strut assembly bolts that passed through bolt insertion holes in the vehicle body. However, the work of assembling the above-mentioned struts is extremely troublesome for workers, as the above-mentioned struts are relatively heavy, and there is a growing demand for automating the work of assembling these struts. There is.

Therefore, one possible method of automating such strut assembly work is to use an industrial robot. In this method, for example, a car body on a line is positioned at a predetermined position, one robot grasps and transports the strut, the other robot transports a fastener tightening device, and the strut is automatically assembled to the car body. It was designed to do so.
In this case, each robot is adapted to transport the strut and fastener tightening device to a predetermined position along a predetermined teaching movement locus. However, with this method, the accuracy of the stopping position of the car body on the line is relatively low even with current control technology, and the struts and fasteners that are conveyed based on the teaching motion of each robot are Generally, the attachment device is displaced from the assembly position on the vehicle body side. Therefore, in order to assemble the strut to the vehicle body, the strut and fastener tightening device must be positioned at the assembly position on the vehicle body side, but if the strut and fastener tightening device are positioned separately, Therefore, the time required for positioning the struts and fastener tightening devices increases, which causes the problem that it is not possible to shorten the time required to assemble the struts. If a robot were to perform the work, a control device would be required, which would complicate the automatic strut assembly device.

Incidentally, such a problem is not limited to the case of assembling the strut, but similarly occurs when assembling other vehicle parts.

The present invention has been made based on the above-mentioned viewpoints, and its purpose is to recognize that the accuracy of the stopping position of the vehicle body on the automobile assembly line is relatively low, and to assemble the vehicle body side. A vehicle component that allows vehicle components and fastener tightening devices to be easily positioned in a short time, and that enables automatic assembly of vehicle components without the need to control a robot for the positioning. An object of the present invention is to provide an automatic assembly method and device for the same.

The basic structure of the automatic assembly method for vehicle parts according to the present invention is that a gripping hand attached to a robot grasps and conveys the vehicle component and attaches it to the vehicle body, and a fastener tightening device attached to another robot When tightening the vehicle parts to the car body, the positional relationship between the vehicle parts brought to the car body and the fastener tightening device brought to the car body is determined based on the movement accuracy of both robots, and then the The vehicle parts and the fastener tightening device are made to float relative to the robot while maintaining their positional relationship, so that the positional relationship with the vehicle body can be determined. Furthermore, the basic configuration of the automatic assembly device used to carry out the method for automatically assembling vehicle parts according to the present invention is that a gripping hand for gripping a vehicle part is attached to one robot, and a fastener tightening hand is attached to one robot. The holding device is attached to the other robot via the support device, and the gripping hand and the support device are configured to be husband and wife so as to support the vehicle parts and the fastener tightening device in a fixed or floating state, and the support device includes: An engaging member that engages with vehicle parts and a guide member that engages self-centripetally with a positioning portion formed on the vehicle body are provided, and the grasping hand and support device are fixed and the vehicle is moved based on the operational accuracy of both robots. Both the vehicle component and the fastener tightening device are pre-positioned by engaging the engagement member with the component, and then the guide member is engaged with the positioning portion of the vehicle body with the gripping hand and the support device in a floating state. By doing so, the vehicle body, vehicle parts, and fastener tightening device are positioned.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method and apparatus for automatically assembling vehicle parts according to the present invention will be described in detail based on embodiments of the apparatus for automatically assembling vehicle parts shown in the accompanying drawings.

FIG. 1 is a perspective explanatory view showing an outline of an automatic assembly process for a strut as a vehicle component. In FIG. 1, a vehicle body B is placed on a conveyor 1 and moved, and is positioned when it reaches the strut assembly position. Assembly equipment is installed. This automatic assembly device moves the gripping hand H that grips the strut P to one of the robots Ra.
At the same time, a nut tightening device N for tightening a nut as a fastener is attached to the other robot Rb via a support device S, and the husband's robot Ra, Rb
After transporting the strut P and nut tightening device N to predetermined positions based on the teaching information, fit the upper case 4 of the strut P into the positioning hole 3 on the top surface of the strut tower 2, and The strut P is assembled to the vehicle body B by passing an assembly bolt 6 erected in the upper case 4 through the bolt insertion hole 5 and tightening a nut 7 to the assembly bolt 6. In FIG. 1, reference numeral 8 indicates a temporary holding table for temporarily holding the strut P to be assembled, and reference numeral 9 indicates a nut supplying device for supplying the nuts 7 to the nut tightening device N.

In this embodiment, the gripping hand H that grips the strut P includes a main body 11 fixed to the multi-joint arm 10 of the robot Ra, and a main body 11 provided on this main body 11, as shown in FIGS. 1 to 5. It is composed of a pair of clamp members 12 that grasp the shaft part Ps of the strut P in a floating manner on a plane parallel to the vehicle body mounting surface (upper surface of the strut tower 2), and a lock member 13 that fixes the clamp members 12. .

As shown in FIGS. 3 and 4, the main body 11 has a robot on the bottom surface of a plate-shaped base plate 14.
While installing the mounting bracket 19 connected to the multi-joint arm 10 of Ra, the base plate 1
A support shaft 15 that supports one end of the strut P coaxially with the arm 10 of the robot Ra is attached to the hole 14a of the robot Ra in a vertically slidable manner. A spring 16 is interposed between the upper end flange 15b of the support shaft 15 and the base plate 14 to always urge the support shaft 15 upward. The base plate 14 has a support 17 parallel to the support shaft 15.
A pair of anti-rotation plates 18 are protruded from the support shaft 15 side of the strut 17 so that a fixing bracket Pb protruding from the shaft Ps of the strut P is inserted into the support strut 17. It's summery. Furthermore, a pair of cylindrical portions 20 are formed on both front and rear sides of the upper part of the support column 17, and each cylindrical portion 2
0, a support rod 22 is attached via a ball bush 21 so as to be slidable in the axial direction.A stopper portion 22a is provided at the lower end of the support rod 22, and a clamp member is provided at the upper end of the support rod 22. Twelve mounting brackets 23 are attached, and a spring 24 is interposed between the mounting brackets 23 and the cylindrical portion 20, so that the support rod 22 is always urged upward.

Further, as shown in FIG. 5, the clamp member 12 includes a pair of movable arms 26 that are pivotally attached to the mounting bracket 23 with a pivot 25 and that open and close in a plane parallel to the base plate 14, and these movable arms 26. and a contact plate 28 which is attached to opposing portions of the strut P via a pair of floating mechanisms 27 and abuts against the shaft portion Ps of the strut P. In this type, the movable arm 26
and the abutting plates 28 each have an expanded U-shape and are arranged symmetrically, and each floating mechanism 27 is provided between the movable arm 26 and the expanded portion of the abutting plate 28, They are arranged every 90° in the radial direction of the shaft portion Ps of the strut P. The floating mechanism 27 includes a spherical bearing 30 fitted and fixed in the mounting hole 29 of the movable arm 26, a sleeve 32 pivotally supported by the spherical bearing 30 via a hollow spherical shaft 31, and A sliding body 33 is slidably mounted through the sleeve 32.
A spherical bearing 35 is fitted and fixed into the mounting hole 34 of the contact plate 28, and the spherical bearing 35 is pivotally supported via a hollow spherical shaft 36a, and is connected and fixed to the tip of the sliding body 33. It is interposed between the connecting body 36, a washer 37 attached to the tip of the sliding body 33, and a flange 32a integrally provided on the sleeve 32, and the sliding body 33 is directed toward the axis Po of the strut P. It is composed of a spring 38 for urging, and a stop washer 39 provided at one end of the sliding body 33 and brought into contact with one end of the sleeve 32 to regulate the amount of movement of the sliding body 33. In FIG. 5, 40 and 41 are retaining rings for fixing the spherical bearings 30 and 35, and 42 is a nut for fixing the sleeve 32. A pair of air cylinders 43 for driving the clamp member 12 are attached to the mounting bracket 23. A piston rod 43a of each air cylinder 43 is connected to the base end of the movable arm 26, and the piston rod 43a is connected to the base end of the movable arm 26.
The movable arm 26 opens and closes in response to the forward and backward movement of the movable arm 26. And the movable arm 2
A bolt stopper 44 is provided protruding from each opposing side of the movable arm 26, and the bolt stopper 44 comes into contact with a stopper piece 45 provided on the mounting bracket 23 to restrict the closed position of the movable arm 26.

Further, the locking member 13 has a piston rod 46 attached to the outside of each movable arm 26.
a is a pair of air cylinders 46 that move forward and backward in the radial direction of the strut P; an insertion hole 47 opened in the movable arm 26 into which the piston rod 46a of the air cylinder 46 is inserted; inserted and the piston rod 46
When the piston rod 46a protrudes, the adapter 49 contacts the side surface of the movable arm 26 of the contact plate 28, and presses the contact plate 28 against the shaft Ps of the strut P. , to fixedly support the clamp member 12.

Further, in this embodiment, the support device S of the nut tightening device N includes a flat base plate 51 fixed to the multi-joint arm 50 of the robot Rb, as shown in FIGS. 1 and 6 to 10. A movable plate 5 is provided on the base plate 51 and supported in a floating manner on a plane parallel to the vehicle body mounting surface of the strut P (the upper surface of the strut tower 2).
2, a locking member 53 for fixing the movable plate 52 at an arbitrary position, a locking mechanism 53' for fixing the movable plate 52 at a normal position, and a lock member 53' for fixing the movable plate 52 at a normal position; An engagement member 55 that engages with the engagement hole 54 of the upper case 4 of the strut P, and a guide member 56 that is provided on the movable plate 52 and engages with the positioning hole 3 on the upper surface of the strut tower 2 in a self-centripetal manner.
A nut tightening device N is mounted on the movable plate 52.

As shown in FIG. 7, a mounting bracket 57 connected to the arm 50 of the robot Rb is attached to the lower surface of the base plate 51, and a floating mechanism 5 is attached to the upper surface of the base plate 51.
A movable plate 52 is attached via 8. As shown in FIGS. 7 and 10, this floating mechanism 58 supports the movable plate 52 at four points, and each floating mechanism 58 supports the movable plate 52 at four points.
The specific configuration of 8 is that the hole 5 of the base plate 51
1a through a bearing 59, a case body 61 connected and fixed to the tip of this rotary shaft 60, and this case body 61.
a sliding shaft 62 that slides on a plane parallel to the base plate 51;
A connecting shaft 64 has one end connected and fixed to the tip of the base plate 5, and the other end is fitted into the hole 52a of the movable plate 52 via a bearing 63.
It is designed to move in any direction while maintaining a positional relationship parallel to 1. Reference numeral 62a is a coil spring that performs self-centering action to some extent even when the nut tightening device N is tilted, and its force is adjusted in consideration of the center of gravity on the movable plate 52. In addition, in FIG. 7, 65 is a bearing holding plate, and 66 is a collar.

Further, as shown in FIGS. 7 and 8, the locking member 53 is provided at two locations, each connected to a rotating shaft 60 constituting the floating mechanism 58.
The magnetic brake is fixed to the lower surface of the base plate 51 and is connected to the rotating shaft 60.
It consists of a cylindrical magnet main body 67 through which the magnet main body 67 passes, and a coupling 68 provided opposite to the lower surface of the magnet main body 67 and connected and fixed to the tip of the rotating shaft 60. When the magnet main body 67 is not energized, the coupling 68 is placed about 0.2mm apart from the magnet body 67,
While the rotating shaft 60 can freely rotate, when the magnet body 67 is energized, the coupling 68 is attracted to the magnet body 67 and the rotation of the rotating shaft 60 is restricted. The positions of the body 61, the sliding shaft 62, and the connecting shaft 64 are uniquely determined, and the movable plate 52 is fixed at a predetermined position.

Further, a locking mechanism 53' is provided between the base plate 51 and the movable plate 52 to fix the movable plate 52 in the normal position, and as shown in FIG. The base plate 5 is located at the front and back of the approximately central portion of 52.
A pair of locating holes 69 are provided that widen toward the first side, and locating pins 70 that fit into the locating holes 69 are attached to the front and rear of the approximate center of the base plate 51 so as to be movable forward and backward. That is, an air cylinder 72 is attached to the center of the base plate 51 by a bolt 71a via a bracket 71 so as to move a piston rod 72a forward and backward in the vertical direction, and a locate pin 70 is attached to the piston rod 72a via an adapter 73. A support plate 74 is attached extending in the front-rear direction, and the locate pin 70 is fixed to this support plate 74. and,
The adapter 73 is slidably fitted into a substantially cylindrical guide bracket 75 fixed to the air cylinder 72, and the anti-rotation plates 76 fixed to the front and rear of the support plate 74 are fitted inside the guide bracket 75.
Since the support plate 74 is always in contact with a planar abutment surface 75a formed by cutting the front and back of the support plate 74, the support plate 74 moves forward and backward without rotating, and the locate pin 70 moves forward and backward at the position corresponding to the locate hole 69. It is movably positioned. The locating pin 70 is composed of a truncated conical portion that fits into the locating hole 69 and a cylindrical portion protruding from the upper surface of the truncated conical portion.
When the second piston rod 72a protrudes, the truncated conical portion of the locate pin 70 moves into the locate hole 69.
The movable plate 52 is tightly fitted into the base plate 5.
1, when the piston rod 72a of the air cylinder 72 moves backward, the cylindrical portion of the locate pin 70 loosely fits into the locate hole 69, and the piston rod 72a of the air cylinder 72 moves backward. The floating amount of the movable plate 52 is set at . The support plate 74 is provided with an adjuster bolt 85 that abuts against the movable plate 52, so that the position of the locate pin 70 can be adjusted.

Furthermore, as shown in FIG. 7, the guide member 56 includes a sliding shaft 78 that is attached to the movable plate 52 via a guide mounting bracket 77 and is provided so as to be slidable in the vertical direction. A guide 79 is attached to the lower end of the shaft 78 and has an inverted truncated conical guide tapered portion 79a that fits into the positioning hole 3 of the strut tower 2, and a guide is installed between the guide 79 and the guide mounting bracket 77. and a spring 80 that always urges the guide 79 downward. Additionally, a stop washer 81 is provided at the upper end of the sliding shaft 78.
is installed.

Further, as shown in FIG. 7, the guide 79 of the guide member 56 has a hollow portion 79b opened downward.
is formed, and in this hollow part 79b, an engagement taper part 82 having an inverted truncated conical shape is formed at the tip.
An engaging member 55 having an engaging portion for engaging the engaging hole 54 of the strut P is incorporated coaxially with the guide member 56. Stepped portion 79
The spring 84 is interposed between the stepped portion 79c and the engagement taper portion 82, so that the spring 84 is always urged downward. The engagement tapered portion 82 of the engagement member 55 is located at a position that always projects downward from the guide 79 of the guide member 56.

Further, in this embodiment, the nut tightening device N is provided corresponding to the bolt insertion hole 5 of the vehicle body, as shown in FIGS. The fixed nut runners 90 are directly fixed to the movable plate 52 via the holding bracket 92, while the movable nut runners 91, 91 are fixed to the fixed nut runners 90. On the other hand, it is arranged symmetrically in the front-rear direction and is fixed via a holding bracket 94 onto a sliding plate 93 that slides in the left-right direction of the movable plate 52. The sliding mechanism 95 of the sliding plate 93 includes an inner case 95a fixed on the movable plate 52, and an outer case 95b slidably fitted to the inner case 95a and fixed to the sliding plate 93. It consists of The sliding plate 93 is attached to an air cylinder 97 attached to the movable plate 52 via a mounting bracket 96.
The adjuster is connected to the piston rod 97a of the piston rod 97a, and is configured to slide in the left-right direction as the piston rod 97a moves forward and backward. By contacting the bolts 99, the stopping position of the sliding plate 93 is regulated. Therefore, the arrangement position of the movable nut runner 91 changes depending on the stop position of the sliding plate 93, so that it is possible to cope with changes in the tightening position of the nut, which differ depending on the type of vehicle. That is, as shown in the embodiment, for vehicle models in which the vehicle body has three bolt insertion holes 5, the movable nut runners 91, 91 may be arranged as shown in FIGS. 7 and 9; For vehicle models that have two bolt insertion holes 5, move the movable nut runners 91, 91 to the left in FIGS. 7 and 9, and use only the movable nut runners 91, 91. All you have to do is tighten the nut.

In addition, the above fixed and movable nut runners 9
As shown in Fig. 7, the rotation axis of 0.91 is
A couple ring 100 is fixed to each, and a joint 10 is attached to the lower end of this couple ring 100.
1 is fixed, and a connecting shaft 102 is attached to the hole of the coupling 100 and the joint 101 so as to be slidable in the vertical direction and prevented from rotating. A nut holding socket 103 is fitted in the lower part of the connecting shaft 102, and a leaf spring 104 is provided in the socket 103 to press against the bitten nut.
Further, a spring 105 is interposed between the lower surface of the joint 101 and a flange 102a provided on the connecting shaft 102, and the connecting shaft 102 is always urged downward.

Therefore, according to the automatic strut assembly apparatus according to this embodiment, as shown in FIG. After that, the vehicle waits at a position where it does not interfere with the vehicle body B being transferred by the conveyor 1. In this process, first of all,
As shown in the figure, in response to a command signal from a control device (not shown), the piston rod 43a of the air cylinder 43 of the gripping hand H is operated to project, and the clamp member 12 is set in the open state. Next, the robot
Ra moves the gripping hand H to the strut P of the temporary stand 8.
After moving it upward and placing the main body 11 facing downward, the gripping hand H is lowered and stopped at a position where the bottom of the strut P contacts the support shaft 15 and the spring 16 balances the weight of the strut P. . Thereafter, in response to a command signal from a control device (not shown), the piston rod 43a of the air cylinder 43 moves backward, the clamp member 12 closes, and the contact plate 28 contacts the shaft Ps of the strut P. Then, since the piston rod 46a of the air cylinder 46 constituting the locking member 13 operates to protrude, the adapter 49 comes into contact with the outer surface of the abutment plate 28, and the abutment plate 28 engages the shaft portion of the strut P.
The strut P is pressed against Ps, and the strut P is securely grasped by the clamp member 12. In this state, as shown in FIGS. 11 and 12, the arm 10 of the robot Ra rotates by a predetermined angle, for example, 30 degrees. At this time, the fixing bracket Pb of the strut P is fitted into the anti-rotation plate 18 of the gripping hand H, and the rotational force of the arm 10 is transmitted to the strut P. assembled bolt 6
is the positioning slit 106 opened in the temporary mounting table 8.
Since the strut P is in the fitted state, the entire strut P rotates while the assembly bolt 6 is moving within the positioning slit 106, but after the assembly bolt 6 contacts the end of the positioning slit 106, the strut P rotates. Only the shaft portion Ps of the strut P rotates, and the upper case 4 rotates idly. Therefore, the relative positional relationship between the assembly bolt 6 and the robot Ra is uniquely determined, and in this state, the robot
Ra pulls out the strut P from the temporary stand 8,
Wait at the designated position. In FIGS. 11 and 12, reference numeral 110 indicates a fitting hole 1 provided in the temporary stand 8 so that the upper case 4 of the strut P fits therein;
Reference numeral 11 denotes a clip that holds the shaft portion Ps of the strut P.

On the other hand, robot Rb, as shown in Figure 1,
After the nut 7 is supplied to the nut tightening device N, the nut 7 is placed on standby at a position where it does not interfere with the vehicle body being transferred on the conveyor 1. In this process, as shown in FIG. 6, first, a vehicle type selection command signal is issued from a control device not shown, and
is moved appropriately and placed in a position according to the vehicle type, and then the piston rod 72a of the air cylinder 72 shown in FIG. positioning is performed. After this,
The robot Rb transports the nut tightening device N to the nut supply device 9 and inserts the nut into the socket 1 of the nut tightening device N.
03 holds the nut 7, and in this state,
Wait at the designated position.

Next, when the vehicle body B stops at a predetermined position, a vehicle body stop completion signal is issued from a control device (not shown), and as shown in FIG. While the robot Rb conveys the strut P so that it faces upward and stops, the robot Rb conveys the nut tightening device N to a position above the strut tower 2 and stops. In this state, the strut P and the nut tightening device N are placed at corresponding positions based on the operating accuracy of the robots Ra and Rb, but the stopping position accuracy of the vehicle body B is determined by the operating accuracy of the robots Ra and Rb. Since the accuracy is low compared to the accuracy, the positioning hole 3 of the strut P is generally shifted in the longitudinal direction of the vehicle body with respect to the positions of the strut P and the nut tightening device N. After this, the robot Rb, as shown in FIGS. 13 and 14,
The nut tightening device N is lowered and stops at a position where the guide tapered surface 79a of the guide member 56 approaches the flange 3a on the edge of the positioning hole 3, while the robot
Ra raises the strut P to a predetermined position.
At this time, the engagement member 55 of the support device S is in a position passing through the positioning hole 3 of the vehicle body, and the engagement taper portion 82 of the engagement member 55 is fitted into the engagement hole 54 of the upper case 4 of the strut P. and the engaging member 55
is pushed up slightly against the spring 84, and the robot Ra stops in this state. This completes the positioning of the strut P and the nut tightening device N. At this time, Natsutranna 90,
The nut 7 held in the socket 103 of 91 is
It is located at a position offset from the bolt insertion hole 5 of the vehicle body.

Thereafter, the vehicle body, strut P, and nut tightening device N are positioned. In this process, first, the locking state of the locking member 13 of the gripping hand H is released as shown in FIG. be done. That is,
The piston rod 46a of the air cylinder 46 moves backward, the adapter 49 comes out of contact with the contact plate 28 of the clamp member 12, and the strut P is floatingly supported in the radial and vertical directions by the floating mechanism 27. That will happen. On the other hand, in response to an engagement completion signal from the control device, the lock mechanism 53' of the support device S is released from the locked state, as shown in FIG. That is, the piston rod 72a of the air cylinder 72 moves backward, causing the locate pin 70 to retreat from the position shown in FIG. The plate 52 is floatingly supported in the plane direction by a floating mechanism 58 shown in FIGS. 7 and 10 in the gap range between the locate pin 70 and the locate hole 69. Thereafter, as shown in FIGS. 13 and 15, when the robot Rb lowers the nut tightening device N, the guide member 56 also lowers accordingly. At this time, the guide tapered portion 79a of this guide 79 comes into contact with the flange 3a on the edge of the positioning hole 3 of the vehicle body. As the guide member 56 further descends from this state, as shown in FIGS. 13 and 16, the guide tapered portion 79 of the guide 79
a is attached to the flange 3 by the action of the spring 80.
Since the guide 79 slides into the positioning hole 3, the guide 79 moves self-centripetally and fits into the positioning hole 3, and the robot Rb stops in this state. During this time,
Guide member 5 via guide mounting bracket 77
A force acts on the movable plate 52 supporting the guide 79 in the same direction as the self-centripetal movement of the guide 79, but since the movable plate 52 is floatingly supported by the base plate 51 by the floating mechanism 58. , the movable plate 52 compresses or expands each coil spring 62a while moving the guide 79.
It will move following the movement of. On the other hand, the engaging member 55 also moves with the self-centripetal movement of the guide 79, but this engaging member 55 is pressed against the strut P by the action of the spring 84, and the strut P Since the strut P is floatingly supported in the radial direction and the vertical direction by the clamp member 12 shown in FIG.
moves following the movement of the engagement member 55. At this time, since the spring coefficients of the springs 16 and 24 that bias the strut P upward are set to be larger than those of the springs 80 and 84 that bias the guide member 56 and the engagement member 55, the strut There is almost no vertical movement of P itself,
Correspondingly, there is almost no vertical movement of the engaging member 55, but the spring 84 is bent in accordance with the downward movement distance of the guide member 56. These operations determine the relative positional relationship of the vehicle body B, strut P, and nut tightening device N, and the nut runners 90 and 91 forming the nut tightening device N are determined.
Each socket 103 corresponds to each bolt insertion hole 5 of the strut tower 2 and
It is placed close to the top surface. After this, the seventh
As shown in the figure and FIG. 10, upon receiving a signal that the robot Rb has stopped, the lock member 5 is
3 is issued, and this command signal causes the magnetic brake, which is the locking member 53, to operate, and the rotating shaft 60 of the floating mechanism 58 is activated.
The rotation of the case body 6 is restricted, and along with this, the case body 6
1. The movement of the sliding shaft 62 and the connecting shaft 64 is restricted, and the movable plate 52 is fixed to the base plate 51. As a result, the nut tightening device N is completely positioned with respect to the vehicle body B, while the strut P is positioned with respect to the vehicle body B via the engagement member 55.

When this state is completed, the robot Ra raises the strut P to the vehicle body assembly position, as shown in FIGS. 13 and 17. At this time, if each assembly bolt 6 of the strut P is set to be shifted in phase by an angle of 2 degrees from each bolt insertion hole 5 of the vehicle body, the assembly bolt 6 is set to the strut tower. 2 Abuts on the lower surface of the upper part. During this time, due to the relationship between the springs 16 and 24 that bias the strut P upward, the guide member 56, and the springs 80 and 84 that bias the engagement member 55, the robot Ra is able to move the strut as shown in FIG. 17a. P is raised, first, the engaging member 55 is pushed up against the biasing force of the spring 84 and brought into contact with the guide member 56, and then, as shown in FIG. 17b, the engaging member 55 and the guide The assembly bolt 6 of the strut P is brought into contact with the upper and lower surfaces of the strut tower 2 by pushing up the member 56 together. In this state, the robot Ra further rises by the axial length of the assembly bolt 6, but the upward movement of the strut P is restrained by the vehicle body, so as shown in Figs.
As shown in the figure, the strut P itself does not rise, and the support shaft 15 and support rod 22 provided on the main body 11 of the gripping hand H face in the axial direction of the strut P, and the springs 16 and 2
It will move against the urging force of 4. As a result, the assembly bolt 6 of the strut P is attached to the spring 1.
The strut tower 2 is brought into pressure contact with the upper and lower surfaces of the strut tower 2 by the biasing forces 6 and 24. After this,
The tip axis of robot Ra is arrow A shown in Fig. 17c.
When the strut P is rotated by a predetermined angle, for example, 4 degrees, the strut P also rotates in the direction of arrow A. At this time, the assembly bolt 6 of the strut P moves while slidingly contacting the upper and lower surfaces of the strut tower 2, and
As shown in Figure d, when the bolt 6 is aligned with the bolt insertion hole 5 of the vehicle body, the bolt 6 passes through the bolt insertion hole 5 by the urging force of the springs 16 and 24, as shown in Figure 17e. do. In this case, the strut P will rotate more than the phase difference between the assembly bolt 6 and the bolt insertion hole 5 (2 degrees in this embodiment), but after the assembly bolt 6 has penetrated the bolt insertion hole 5. Since the rotation of the upper case 4 of the strut P is restricted, the shaft of the strut P
Only Ps will be idle. In this state, the assembly bolt 6 that has passed through the bolt insertion hole 5
As shown in FIG. 17e, the nut runner 9
It comes into contact with the lower surface of the nut 7 fitted into each of the sockets 103 No. 0 and 91, and pushes the sockets 103 upward against the biasing force of the spring 105. Then, when each socket 103 is pushed upward by a predetermined amount, a limit switch or the like (not shown) is activated, and a nut tightening preparation completion signal indicating that the assembly bolt 6 has passed through the bolt insertion hole 5 is sent to the control device. Sent.

Thereafter, each nut runner 90, 91, which is the nut tightening device N, is tightened by a command signal from the control device.
The rotating shaft of the nut 7 rotates, and as shown in FIG. ), the rotation of the rotation shafts of the nut runners 90, 91 is stopped. At this time, the assembly bolt 6 is pulled upward as the nut 7 is tightened, so that when the tightening of the nut 7 reaches the specified torque, the strut P is reliably assembled to the predetermined position on the vehicle body. become.

When the control device issues a nut tightening completion signal, the gripping hand H
The clamp member 12 opens and the shaft of the strut P
After the grip state of Ps is released, the robot Ra will
The gripping hand H is moved back so as not to interfere with the assembled strut P, and returned to its original position in preparation for the next process. At the same time, as shown in FIG. 7, the power supply to the magnetic brake, which is the locking member 53 of the support device S, is cut off, and after the movable plate 52 returns to the floating state, the robot Rb moves as shown in FIG. The nut tightening device N is raised and returned to its original position in preparation for the next process. At this time, since the movable plate 52 is in a floating state, even if the robot Rb rises, there is no concern that an excessive load will be applied to each part of the support device S. At this stage, as shown in FIG. 19, the assembly process for one strut P is completed.

In the above embodiment, the main body 11 of the gripping hand H connects the lower end of the strut P to the support shaft 1.
Although the support shaft 15 is not particularly necessary, the strut P may be gripped using only the clamp member 12. Further, the clamp member 12 has a floating mechanism 27 interposed between the movable arm 26 and the abutment plate 28, but is not necessarily limited to this, and the pair of clamp arms can be connected to the floating mechanism 27. The design may be changed as appropriate, such as by directly attaching it to the main body 11 via a holding mechanism. Furthermore, in the above embodiment, the floating mechanism 27
The strut P is supported in a floating manner in its radial and axial directions, but the design may be modified as appropriate as long as it is supported in a floating manner at least in the radial direction. Furthermore, it goes without saying that the locking means for fixing the clamp member 12 is not limited to the locking member 13 shown in the embodiment. Furthermore, the floating mechanism 58 and locking means of the support device S are not limited to those shown in the embodiments, and may be modified in design as appropriate. Furthermore, in the above embodiment, the guide member 56 of the support device S
and the engaging member 55 are provided coaxially, and the guide member 56 is adapted to engage with the positioning hole 3 of the strut S, but the invention is not necessarily limited to this. For example, as shown in FIG. As shown, the guide member 56 and the engaging member 55 are provided on separate shafts, and the positioning hole, positioning recess 107, etc., with which the guide member 56 engages self-centripetally, is positioned separately from the positioning hole 3 of the strut S. It is also possible to form a section. Further, the above-mentioned engaging member 55 is adapted to engage with the engaging hole 54 of the upper case 4 of the strut P, but it is not necessarily limited to this. For example, as shown in FIG. 21, The upper case 4 of the strut P is provided with the engagement protrusion 108, while the engagement member 55 has the engagement protrusion 10 at its tip.
It goes without saying that the design can be changed as appropriate, such as by providing an engaging recess 109 that engages with 8. Furthermore, in the above embodiment, the strut P is used as an example of a vehicle component, but it goes without saying that the present invention can be applied to the assembly of other vehicle components. In this case, if a weld nut or the like is previously provided on the vehicle component side, a bolt tightening device may be attached to the robot Rb instead of the nut tightening device N.

As explained above, according to the method and device for automatically assembling vehicle parts according to the present invention, a gripping hand attached to a robot can grasp and transport a vehicle part to attach it to a vehicle body, and also attach it to another robot. When tightening the vehicle parts to the vehicle body with the fastener tightening device, based on the operating accuracy of both robots,
Determining the positional relationship between the vehicle parts brought to the vehicle body and the fastener tightening device brought to the vehicle body,
After that, while maintaining the above-mentioned positional relationship, the vehicle parts and fastener tightening device were made to float relative to the robot to determine the positional relationship with the car body, so the accuracy of the stopping position of the car body on the car assembly line was relatively high. Even if it is low, vehicle parts and fastener tightening devices can be easily positioned in a short time with respect to the vehicle body, and there is no need to control a robot for the positioning. Therefore, automatic assembly of vehicle parts can be achieved while reducing the time required for assembly of vehicle parts and without making the assembly apparatus unnecessarily complicated.

[Brief explanation of drawings]

Figure 1 shows a vehicle part (strut) according to the present invention.
FIG. 2 is a perspective view showing an example of a gripping hand for gripping vehicle parts, FIG. 3 is a partially cutaway front view thereof, and FIG. FIG. 5 is a partially broken right side view, FIG. 5 is a partially broken plan view, FIG. 6 is a perspective view showing an example of a support device for supporting a fastener (nut) tightening device, and FIG. 7 is a partially broken front view. Fig. 8 is a partially cutaway right side view of the same, Fig. 9 is a plan view thereof, Fig. 10 is a partially cutaway sectional view taken along the line - - in Fig. 7, and Fig. 11 is an example of a temporary storage stand for vehicle parts. FIG. 12 is a cross-sectional view showing the state of a gripping hand that grips a vehicle component on a temporary storage stand, and FIG. 13 is a relative positional relationship between the vehicle body, vehicle component, and fastener tightening device before the vehicle component is assembled. 14 is an explanatory cross-sectional view of a main part showing the first step of the vehicle parts assembly process, and FIGS. 15 and 16 are main parts showing the second step of the vehicle parts assembly process. Cross-sectional explanatory views, Figures 17a to 17e are cross-sectional explanatory views of main parts showing the third step of the assembly process of vehicle parts (However, Figures 17c and d are views taken from the direction of arrow C in Figure 17b. Fig. 18 is a cross-sectional explanatory view of the main part showing the fourth step of the assembly process of vehicle parts, Fig. 19 is a cross-sectional explanatory view of the main part showing the state when the assembly of vehicle parts is completed, and Fig. 20 is FIG. 21 is a cross-sectional explanatory view of a main part showing a modification example of positioning using a guide member, and FIG. 21 is a cross-sectional explanatory diagram of a main part showing a modification example of an engagement member. B...Vehicle body, H...Gripping hand, N...Nut tightening device (fastener tightening device), P...Strut (vehicle parts), Ra, Rb...Robot, S...Support device, 3... ...Positioning hole (positioning part), 6...
Assembly bolt, 7... Nut (fastener), 11...
Main body, 12... Clamp member, 13... Lock member (locking means), 16, 24... Spring (biasing means), 26... Movable arm, 27... Floating mechanism, 28... Contact plate, 32... Sleeve, 33... Sliding body, 36... Connecting body, 38...
... Spring, 51 ... Base plate (base member), 52 ... Movable plate (movable member), 53
...Lock member (lock means), 53'...Lock mechanism (lock means), 55...Engagement member, 56...
... Guide member, 58 ... Floating mechanism, 6
0... Rotating shaft, 61... Case body, 62...
...Sliding shaft, 64...Connection shaft, 69...
... Locate hole, 70... Locate pin, 79a...
... Guide taper part, 90, 91 ... Nut runner, 107 ... Positioning recess (positioning part).

Claims (1)

[Scope of Claims] 1. A gripping hand attached to a robot grasps and transports a vehicle part and attaches it to the vehicle body, and a fastener tightening device attached to another robot tightens the vehicle part to the vehicle body. After determining the positional relationship between the brought vehicle parts and the fastener tightening device brought to the car body, the vehicle parts and the fastener tightening device are made to float relative to the robot while maintaining the positional relationship, and the car body is A method for automatically assembling vehicle parts, characterized in that the positional relationship with the vehicle parts is determined. 2. In an automatic vehicle parts assembly device that assembles vehicle parts to predetermined parts of a vehicle body via fasteners, a gripping hand for gripping the vehicle parts is attached to one robot, and a fastener for tightening the fasteners is attached to one robot. The tightening device is attached to the other robot via a support device, and the gripping hand is connected to a main body fixed to the robot, a clamp member provided on the main body for movably gripping the vehicle component, and a clamp member for movably gripping the vehicle component. and a locking means for fixing the clamp member so as to restrict its movement, while the support device is comprised of a base member fixed to the robot, and a fastener tightening device fixed to the base member and floatingly supported by the base member. a locking means for fixing and unfixing the movable member to the base member; an engaging member provided on the movable member to engage with a vehicle component gripped by the gripping hand; and a guide member that engages in a self-centripetal manner with a positioning portion formed on the vehicle body, and the clamp member and the movable member are fixed, and the engaging member is engaged with the vehicle component to be fastened to the vehicle component. Next, the clamp member and the movable member are placed in a floating state, and the guide member is engaged with the positioning portion of the vehicle body, thereby positioning the vehicle body, vehicle parts, and the fastener tightening device. An automatic assembly device for vehicle parts characterized by positioning three parts.