JPH06155190A - Workpiece mounting device - Google Patents

Abstract

(57) [Summary] [Purpose] Positioning of a work in a device that positions a work from below on a structure with downward stud bolts and attaches the work to the structure by screwing a nut onto the stud bolt. And the mounting can be done more accurately. [Structure] On the support base 2 that moves up and down while being suspended and supported,
A positioning clamper 3 for gripping the stud bolt S on the vehicle body B side, which is a structure, a lift 4 for mounting a work (subframe S) that moves up and down on the support base 2, and a vertical movement toward the stud bolt S. Work attachment device equipped with a nut runner 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work attachment device used for attaching a work such as a frame to a vehicle body from below in a vehicle assembly process.

[0002]

2. Description of the Related Art FIG. 8 shows a cross member 1 which constitutes a vehicle body.
It is a figure which shows the apparatus which attaches the sub-frame 102 to the 01 from the lower side.

The cross member 101 is provided with a downward stud bolt 103 at a mounting position of the sub-frame 102 and is joined to a side member 104 by spot welding. The sub-frame 102 has a bolt insertion hole 105 and is mounted on a lift 106.

Locate holes 107 and locate pins 108 are provided on the vehicle body side and the lift 106 side.
Since these cannot be provided at the positions of the cross member 101 and the sub-frame 102 facing each other, the side member 104 is provided with a locate hole 107, and the lift 106 is extended to the side of the bracket 10.
Locating pin 108 is provided through 9.

The above-mentioned work attaching device is equipped with a lift 106.
When the locating pin 108 is inserted into the locating hole 107 in the process of raising the stud, the stud bolt 1
03 and the bolt insertion hole 105 of the sub-frame 102 are aligned on the coaxial line, and the stud bolt 103 is inserted into the bolt insertion hole 105.
The attachment of the sub-frame 102 is completed by screwing a nut onto (for such work, for example,
It is introduced in Japanese Utility Model Laid-Open No. 58-22387. ).

[0006]

By the way, as described above, in the conventional work attaching device using the locate hole 107 of the side member 104 and the locate pin 108 of the lift 106, the cross member 101 joined by spot welding. It is necessary to make the joining accuracy of the side member 104 and the side member 104 extremely high, and if the accuracy is impaired, the stud bolt 103 and the bolt insertion hole 105 will be displaced.

However, the joining accuracy of the cross member and the side member has some variation even in the range where the joining state is good because it is welding joining.
This variation has no problem in terms of strength.
On the other hand, the positional accuracy between the stud bolt and the bolt insertion hole is required to be extremely high.

That is, in the conventional work attaching apparatus, there is a problem that the positional relationship between the stud bolt and the bolt insertion hole, which should be more accurate than this, is influenced by the joining accuracy of the vehicle body in the previous process. Resolving such a problem has been a problem in improving the work mounting accuracy.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the conventional state as described above, and accurately positions and attaches a work to a stud bolt on the structure side without using a locate hole and a locate pin. It is an object of the present invention to provide a work attachment device capable of performing the work attachment.

[0010]

According to a first aspect of the present invention, there is provided a work attaching device, wherein a work is positioned from below on a structure having downward stud bolts, and nuts are screwed to the stud bolts. A device for attaching a work to the structure by means of the above, wherein a positioning clamper for holding the stud bolts is provided on a support base that is lifted and lowered in a floating support state, and a work placement lift that is raised and lowered on the support base. And a structure in which the lift is provided with a nut runner that moves up and down toward the stud bolt. Further, according to claim 2, the positioning clamper includes a pair of claws that are closely spaced from each other by a driving cylinder. And a detector for contacting the stud bolt is provided on at least one of the grips of the claws, and the cylinder and the driving fluid are connected to each other. A high-pressure flow path and a low-pressure flow path provided with a pressure reducing valve are provided between the power source and a switching valve for switching the low-pressure flow path to the high-pressure flow path according to a signal from the detector. Therefore, these configurations are used as means for solving the problems.

[0011]

In the work attaching apparatus according to the first aspect of the present invention, since the positioning clamper, the lift on which the work is placed and the nut runner are floatingly supported together with the support base, the stud bolts provided on the structure are In the process of gripping with the positioning clamper, the positions of the lift and nut runner along with the support are corrected corresponding to the positions of the stud bolts, and the work is positioned when the stud bolts are completely gripped by the positioning clamper. Becomes

Therefore, if the work is lifted by the lift in the above state, the stud bolt is inserted into the work while maintaining the mutual positional relationship, and then the nut runner is used to screw the nut to the stud bolt. The work is attached to the structure.

Further, in the work attaching device according to the second aspect of the present invention, when the stud bolt is gripped by the positioning clamper, the driving fluid is supplied to the driving cylinder through the low pressure passage having the pressure reducing valve and the switching valve. Is supplied to gently bring the pair of claws close to each other. As a result, the above-described lift and nut runner position correcting operations are smoothly performed. Furthermore, when the positioning clamper starts gripping, a large impact force is not applied to the stud bolt, and the stud bolt is not deformed.

When the detector comes into contact with the stud bolt, the work attaching apparatus operates the switching valve by a signal from the detector, and supplies the driving fluid to the driving cylinder through the high pressure passage. , Hold the stud bolt tightly with a pair of claws. As a result, the workpiece positioning state is maintained.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

The work mounting device shown in FIGS. 1 and 2 mounts a sub-frame (work) W from below on a cross member C that constitutes a vehicle body (structure) B of an automobile.

The vehicle body B continues to move along the assembly line while being suspended from the hanger H. Also,
On the lower surface of the cross member C, downward stud bolts S, S are provided at two places on the left and right.

The work attaching device is provided with a support base 2 which is raised and lowered in a floating support state on a carriage 1 which can be reciprocally moved along an assembly line. The support base 2 is provided with respective stud bolts S, S. Positioning clampers 3 and 3 to grip,
A lift 4 for placing a work is provided, and the lift 4 is provided.
It is equipped with nutrunners 5 and 5.

The dolly 1 is provided with a base 7 having a substrate 6 provided on the upper part thereof, and a frame 8 is erected at a rear end portion in the traveling direction of the assembly line (left direction in FIG. 1). At the upper end of the frame 8, a trolley synchronizing clamper 9 for holding the hanger H is provided. The base 7 accommodates therein equipment for controlling a cylinder and the like described later, and a cable bear 10 for supplying power is provided between the base 7 and the floor side.

On the front and rear direction side of the carriage of the base plate 6, the whole lifting cylinders 11, 11 are provided with respective cylinder rods 11a, 1c.
1a is provided in an upward direction, and the plate 1 for raising and lowering the entire body is provided at the upper end of each cylinder rod 11a, 11a.
2 is fixed. Also, on the plate 12, 4
The support base 2 is movably provided in the horizontal direction via the individual free bears 13. Thereby, the support base 2
Is capable of moving up and down while being suspended and supported.

The support base 2 is provided with two lift lifting cylinders 14 and 14 with the cylinder rods 14a and 14a facing upward.

The lift 4 includes the cylinder rod 14
The lower plate 15 is fixed to the upper ends of the a and 14a, and the upper plate 17 is rotatably held by a support shaft 16 standing upright in the center of the lower plate 15.
A motor 18 for rotating the work is provided on the lower plate 15, and the gear 1 fixed to the output shaft of the motor 18 is provided.
The upper plate 17 is rotated by the motor 18 by engaging the gear 9 fixed to the support shaft 16 with the gear 9. On the upper plate 17,
Two roller conveyors 20 and 20 for carrying in a work are provided in parallel.

Further, on the left and right sides of the lower plate 15 in the bogie traveling direction, a vertical cylinder mounting plate 21,
21 are fixed, and a nut runner 5 is attached upward to each mounting plate 21 via a vertical guide rail 22 and a slider 23 slidably engaged with the vertical guide rail 22. Each nut runner 5 is driven up and down while being guided by the guide rail 22 by a nut runner lifting cylinder 24 mounted on the mounting plate 21.

The support base 2 has frames 25, 2 which extend to the left and right in the traveling direction of the carriage and rise upward.
5 is fixed, and at the upper end of each frame 25, a cylinder 27 for advancing and retracting the clamper is provided together with a horizontal plate 26. Each of the positioning clampers 3 is driven toward and away from the center of the carriage by the clamper advancing and retracting cylinder 27.

As shown in FIG. 3, each positioning clamper 3 has two holder-shaped air cylinders 29, 29 for driving clampers in a holder 28 having an L-shaped cross section which is connected to the cylinder 27 for advancing and retracting the clamper. , Each other's cylinder rod 29
a and 29a are fixed in the opposite direction,
Arms 30 and 30 extending toward the center of the truck are fixed to the tip ends of the cylinder rods 29a and 29a, and gripping portions 31a and 31a in a substantially V-shaped notch are provided on both arms 30 and 30, respectively. The claws 31 and 31 that it has are provided. The both claws 31, 31 in this embodiment are provided at positions which are vertically different.

Further, as shown in FIG. 4, each of the positioning clampers 3 has two limiters in which a contact 32a is extended in the grip 31a of one of the claws 31 in the depth direction of the grip 31a. Switches (detectors) 32, 32 are provided.

Further, between the air cylinders 29, 29 and the air supply source (driving fluid supply source) 33, a high pressure passage 34 and a low pressure passage 3 having a pressure reducing valve 35 in the middle are provided.
6 and 6 are provided in parallel, and these flow paths 34, 3
An electromagnetically driven switching valve 37 for switching 6 is provided, to which the limit switches 32, 32 are electrically connected. When there is no signal from the limit switch 32, the switching valve 37 uses the low pressure passage 36.
And each air cylinder 29 are in communication with each other.

Next, the operation of the work attaching device having the above configuration will be described with reference to the time chart of FIG.

The work attaching device stands by at the loading side of the vehicle body B in the attachment area of the subframe W,
At this time, the support base 2, the lift 4, and the nut runner 5 are all in the lower limit, and the positioning clamper 3 is in the upper limit. Further, the upper plate 17 of the lift 4 is in the original position rotated by 90 degrees from the state shown in FIGS. 1 and 2, and in this state the subframe W is loaded from the side of the carriage.
Is received on the roller conveyor 20. Therefore, for convenience of carrying in the sub-frame W, the avoidance mechanism may be provided in the frame 25 of the one positioning clamper 3.

In the work mounting apparatus, when the vehicle body B enters the mounting area, the work rotating motor 18 rotates the upper plate 17 by 90 degrees so that the sub-frame W is oriented as shown in FIGS. The hanger H is gripped by the cart synchronizing clamper 9. After that, the work attaching device is moved in parallel with the vehicle body B by the carriage 1.

Next, the work mounting device drives the entire lifting cylinders 11 and 11 to the upper limit to raise the support base 2 and the positioning clamper 3 and the lift 4 and the like. At this time, the positioning clamper 3
Reaches a height at which the intermediate portion of the stud bolt S can be gripped, as shown by the phantom line in FIGS. 1 and 2.

Further, in the work attaching device, each stud bolt S is grasped from the front-rear direction of the vehicle body by each positioning clamper 3 so that each stud bolt S, S and the bolt insertion hole A, A of the sub-frame W are connected. Match on the coaxial line.

That is, since the positioning clamper 3, the lift 4 and the nut runner 5 are floatingly supported together with the support base 2 in the work mounting apparatus, the process of gripping the stud bolt S by the positioning clamper 3 is performed. In the above, the positions of the lift 4 and the nut runner 5 together with the support base 2 are corrected corresponding to the positions of the stud bolts, and when the stud bolts S are completely gripped, the subframe W is consequently positioned. Becomes

At the work mounting position, when the stud bolt S is gripped by the positioning clamper 3,
Air is supplied to the air cylinder 29 for driving the clamper through the low-pressure passage 36 provided with the pressure reducing valve 35 and the switching valve 37, so that the pair of claws 31 and 31 are gradually moved closer to each other, and the lift described above is provided. The positions of the nut 4 and the nut runner 5 are corrected smoothly. Therefore, when the positioning clamper 3 starts gripping, a large impact force is not applied to the stud bolt S, and there is no fear of deforming the stud bolt S at all.

In the positioning clamper 3, when the contact 32a of the limit switch 32 comes into contact with the stud bolt S, as shown in FIG.
The switching valve 37 is actuated by the signal from and the air is supplied to the air cylinder 29 through the high-pressure passage 34, whereby the pair of claws 31, 31 firmly hold the stud bolt S, and the sub-frame W. The positioning state of is surely maintained.

Next, as shown in FIG. 7, the work attaching device raises the lift lifting cylinders 14 and 14 to place the stud bolts S and S in the bolt insertion holes A and A of the subframe W. To do. At this time, the sub-frame W rises while the horizontal positional relationship with the stud bolt S is maintained due to the holding constraint of the positioning clamper 3. Further, in this embodiment, when the stud bolt S enters the bolt insertion hole A while the lift 4 is rising, the gripping by the positioning clamper 3 is released, and the respective clamper advancing / retreating cylinders 27 are operated to operate the respective positioning clampers. I am trying to retreat 3.

After this, the work mounting device is operated by the nut runner lifting cylinders 2 as shown by the phantom lines in FIG.
4 is operated to raise the nut runner 5, and the nut is screwed to each stud bolt S, whereby the attachment of the subframe W to the vehicle body B is completed.

After the above installation is completed, the nut runner 5, the lift 4 and the support base 2 are lowered, the positioning clamper 3 is advanced, and then the carriage synchronization clamper 9 is moved.
After releasing the grip of the hanger H by, the carriage 1 is retracted by a drive mechanism (not shown) and stands by for the next loading of the vehicle body B.

The work mounting device according to the present invention is
For example, in the case of having two positioning clampers, one stud bolt may be grasped in the front-rear direction by one clamper and the other stud bolt may be grasped in the left-right direction by the other clamper. The invention is not limited to the above embodiment.

[0040]

As described above, according to the work attaching apparatus of the present invention, the stud bolt on the structure side is directly gripped by the positioning clamper, and the positioning is performed on the floating support table. Since it has a clamper and a lift for placing the work, the work can be accurately positioned with respect to the stud bolt without using the locate holes and locate pins that have been used in the past, and the work can be performed very well. Can be installed.

Further, even when the positional displacement between the positioning clamper and the stud bolt that enters between the pair of claws of the clamper is relatively large when the support base is raised, this should be taken care of. It is possible to perform accurate positioning.

Further, in the work attaching device of the present invention,
When gripping the stud bolt with the positioning clamper,
After the pair of claws are gently moved close to each other, the stud bolt is finally held with a large force, so that when the positioning clamper starts gripping, a large impact force is not applied to the stud bolt. It is possible to completely prevent the risk of deformation of the work, and to make the position correction operation of the work suspended and supported together with the support base and lift even smoother, and to ensure the state after positioning. Can be maintained.

[Brief description of drawings]

FIG. 1 is a side view showing a work mounting apparatus according to an embodiment of the present invention, in which a front side positioning clamper is omitted.

2 is a front view of the work attaching device shown in FIG. 1. FIG.

FIG. 3 is a perspective view illustrating a structure of a work positioning clamper.

FIG. 4 is an explanatory plan view showing a work positioning clamper in an unclamped state together with an air supply system.

FIG. 5 is an explanatory plan view showing a work positioning clamper in a clamped state together with an air supply system.

FIG. 6 is a time chart for explaining the movement of each drive unit in the work attaching device.

FIG. 7 is a front view of an essential part showing a state where a lift is raised.

FIG. 8 is an explanatory view showing a conventional sub-frame attaching device.

[Explanation of symbols]

 B Body (Structure) S Stud Bolt W Sub-frame (Work) 2 Support 3 Positioning Clamper 4 Work Placement Lift 29 Air Cylinder (for Clamper Drive) 31 Claw 32 Limit Switch (Detector) 33 Air Supply Source (Driving fluid supply source) 34 High pressure flow path 35 Pressure reducing valve 36 Low pressure flow path 37 Switching valve

Claims (2)

[Claims] 1. An apparatus for positioning a work from below on a structure provided with downward stud bolts, and attaching a work to the structure by screwing a nut onto the stud bolt, which is floatingly supported. The support table that moves up and down in the state is provided with a positioning clamper that holds the stud bolts and a work placement lift that moves up and down on the support table.The lift includes a nut runner that moves up and down toward the stud bolts. A work attachment device characterized by being provided. 2. The positioning clamper includes a pair of claws that are moved closer to and separated from each other by a driving cylinder, and a gripper of at least one of the claws is provided with a detector that contacts a stud bolt. A high pressure passage and a low pressure passage provided with a pressure reducing valve were provided between the fluid supply source and a switching valve for switching the low pressure passage to the high pressure passage in response to a signal from the detector. The work mounting device according to claim 1, wherein