JPS643625Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an automatic screw tightening machine with a workpiece holding device that is suitable for an automatic assembly line that is intended to be unmanned. In order to fasten the required workpieces to the fastened objects being transported on the assembly line, conventionally, a work supply device was installed on the side of the line to supply a unit number of workpieces to a predetermined position on the fastened objects. A screw tightening machine for screwing the workpiece supplied onto the object to be fastened by the supply device was provided separately. However, in this conventional configuration, the supply and fastening of the workpieces are performed separately, which requires a longer assembly line, and additional costs such as the costs required to install each piece of equipment are high. There is a drawback that it sticks. In addition, since the screw tightening position is determined by the positioning of the workpiece, the relative arrangement between the workpiece supply device and the screwdriver must be adjusted, and this adjustment is very cumbersome. It also has shortcomings.

The present invention attempts to eliminate the above-mentioned drawbacks by making it possible to supply and tighten a workpiece to an object to be fastened using a single screwdriver.

The configuration of the present invention will be explained below based on the drawings. FIG. 1 shows an embodiment of the present invention, in which 1 is an assembly line for transporting objects A to be fastened, 2 is a workpiece take-out section provided on one side of the line 1, and 3 is this workpiece take-out section 2. A screw fastening unit 4 reciprocates between the workpiece and the line 1 to take out a workpiece, for example, a plate, onto the workpiece take-out section 2, supplies it to the object A on the line 1, and fastens it. It is an item equipped with a mechanism for reciprocating the reciprocating movement, and is attached to a main rod 5 erected on the side of the line 1. As shown in FIG. 2, one side of this body 4 is formed with an inverted U-shaped groove 6 consisting of an inclined part extending diagonally downward and a vertical part, and at a position above this groove 6. A rotating block 7 is rotatably supported around a point P. The rotating block 7 has two shaft rods 8,
8 is slidably inserted therethrough, and an instruction block 9 for attaching the screw tightening unit 3 is fixed to the shaft rods 8,8.

A rod 10 is inserted into the support block 9 from the rear side through the groove 6 and into the body 4. As shown in FIG. 3, this rod 10 is held between and engaged with a crank lever 11 having two prongs of sufficient size to have a range of movement that covers the inverted U-shaped groove 6. It is configured.

The crank lever 11 is connected to a pinion 12, and the pinion 12 is meshed with a rack 14 attached to a telescopic cylinder 13. Therefore, when the telescoping cylinder 13 is telescopically operated, the crank lever 11 rotates, and the support block 9 moves along the groove 6, tracing an inverted U-shaped trajectory with the point P of the rotary block 7 as the center. Perform a reciprocating motion. Of the two dead points of the reciprocating movement, one is set so that the tip of the screw tightening unit 3 contacts the fastened object A placed at a predetermined position on the line 1, and the other is set such that the tip of the screw tightening unit 3 contacts the workpiece take-out section 2. Or it is adjusted to the closest position.

As shown in FIGS. 4A and 4, the screw tightening unit 3 includes an air or electric motor 15,
15, and bit 1 rotated by the motor.
6, 16, a nose 17, 17 having a guide hole for the bit and a supply hole for the screw, and a pair of jaws 18, 18 provided at the lower end of the nose. A known screw tightening unit is used. However, above 2
A chuck mechanism 19 is provided between the two noses 17, 17 for taking out and holding a workpiece. In the illustrated example, the chuck mechanism 19 is a vacuum chuck mechanism consisting of a block 21 with the tip of a hole 20 facing downward and connected to a vacuum pump (not shown). As the chuck mechanism, it is also possible to employ a mechanism such as a magnetic chuck that attracts the workpiece by magnetic force. Motor 1 of screw tightening unit 3 with this configuration
5 and 15 are installed on an upper stand 22 that is slidably provided on the shaft rods 8 and 8, and the noses 17 and 17 and the chuck mechanism 19 are slidably provided on the shaft rods 8 and 8 and are mounted on a stopper at the lower end of the shaft rod 8. Lower stand 2 secured with
It is attached to 3. Further, the upper stand 22 is fixed to the rod of a telescopic cylinder 24 provided on the support block 9, and the lower stand 23 is fixed to the upper stand 2 of another telescopic cylinder 29 provided on the support block 9.
It is supported by a nut at the lower end of the rod that passes through 2. A spring 25 biases the lower base 23 downward. The telescopic cylinder 24 expands and tightens the screw when the screw is tightened. On the other hand, another one
The two telescopic cylinders 29 function to temporarily project the bit 16 so that the screw does not remain in the jaws 18, 18 after the screw tightening operation.

Next, the workpiece take-out section 2 includes a table 26 on which a workpiece is placed, a magazine 27 that stores a large number of workpieces in a stacked state, and a magazine 27 that slides.
The cutting tool 28 cuts out the work pieces one by one from the magazine 27 onto the table 26 by entering into the lower end of the magazine 27.

The table 26 is configured to change its posture between a posture suitable for receiving a workpiece cut out from a magazine 27 and a posture suitable for the chuck mechanism 19 to take out the workpiece. Here, the posture suitable for the chuck mechanism 19 to take out the workpiece is the posture in which the chuck mechanism 19 is configuring the block 21.
It is desirable that the lower surface of the table 26 be parallel to the surface on which the table 26 is placed. Therefore, when the workpiece is taken out, the screw tightening unit 3 is at one dead center of its inverted U-shaped movement and its posture at that time is inclined, so that the table 26 must also be inclined in accordance with the inclination. The workpiece cutting operation by the workpiece cutting tool 28 is related to the reciprocating movement of the screw fastening unit 3 by an appropriate mechanism not shown.

According to the above structure, when the telescopic cylinder 13 attached to the body 4 is moved forward, the rack 14 moves forward, the pinion 12 rotates, and the crank lever 11 integrated therewith moves counterclockwise in FIG. Rotate to. Therefore, the rod 10, which is locked to the two prongs at the tip of the crank lever 11, moves along the two prongs and from the vertical part of the inverted U-shaped groove 6 to the inclined part. The support block 9 to which the rod 10 is fixed also rises once and then descends while tilting along the slope of the inverted U-shaped groove 6. As the support block 9 moves, the screw tightening unit 3 fixed thereto also moves, and the chuck mechanism 1 at its lower end moves.
9, the workpiece at the workpiece take-out position is sucked.

After that, when the telescopic cylinder 13 retreats,
The crank lever 11 rotates clockwise, and the rod 1
0 is moved from the inclined part of the inverted U-shaped groove 6 to the vertical part. Therefore, the support block 9 is attached to the assembly line 1.
The chuck mechanism 1 descends from above the upper fastened object.
At step 9, the suctioned workpiece is placed at a predetermined position on the object to be fastened. In this state, the telescopic cylinder 13 further retreats and the support block 9 descends, but the lower stand 23
is locked to a nut fixed to the rod of the telescopic cylinder 29, so the chuck mechanism 19 and the screw feeding device are stopped at that position. After that, only the bit 16 moves forward, and the bit 16 screws the screws held by the jaws 18, 18 of the screw supply device into the workpiece to be fastened. The process up to fastening to an object can be performed with one work machine and in a series of operations.

Since the automatic screw tightening machine with a workpiece holding device according to the present invention is constructed as described above, it has the following effects.

Since the feeding and tightening of the workpieces are performed by a single machine, the space required on the line for feeding and tightening the workpieces is halved compared to the conventional method. Therefore, in addition to being able to shorten the assembly line length, incidental costs such as installation costs can be reduced.

Since the workpiece is supplied and tightened by the same machine at the same time, cycle time is reduced and assembly speed is increased.

Since the workpiece can be supplied and fastened using the same machine, the complicated adjustments required in the past are completely unnecessary.

By continuing the holding action of the workpiece by the chuck mechanism until the workpiece is fastened, it is possible to prevent the workpiece from shifting its position, thereby ensuring reliable fastening.

In addition, the present invention allows a single cylinder to perform the operations from suctioning the workpiece to a position a predetermined distance away, and lowering and operating the screw tightening unit at this position. No equipment is required, the control is simple, and an extremely inexpensive and simple automatic machine can be provided.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a perspective view showing the overall configuration, Figs. 2 and 3 are views showing a mechanism for reciprocating the screw fastening unit according to the invention, and Fig. Figure A is a front view with the main parts of the invention cut away.
FIG. 4B is a side sectional view with a main part of FIG. 4A cut away. 1... Assembly line, 2... Workpiece take-out section, 3
...Screw tightening unit, 19...Chuck mechanism, A
...The object to be concluded.

Claims (1)

[Claims for Utility Model Registration] A body 4 is attached to a main rod 5 erected on the side of the line 1, a rotary block 7 is rotatably arranged on the side of the body 4, and a shaft is attached to the rotary block 7. A rod 8 is slidably inserted through the rod 8, and a support block 9 to which a screw tightening unit 3 is fixed is fixed to the lower end of the rod 8.
An inverted U-shaped groove 6 consisting of an inclined part extending diagonally downward and a vertical part is formed on the side surface of the body 4, and the rod 10 that passes through this groove and moves along it is attached to the support block 9. A rack 1 is fixed to the body 4, and further includes a rack 1 which is reciprocated along the side surface of the body 4 by the operation of a telescopic cylinder 13.
4 and a pinion 12 meshing with this rack 14.
The pinion 12 is provided with the inverted U-shaped groove 6.
A crank lever 11 having a two-pronged portion at its tip that is large enough to have a movement range that covers the two parts is fixed.
While the rod is engaged with the prong, the shaft rod 8 has a screw feeding device having a pair of jaws 18, 18 and a lower end located below this, and supplies a workpiece below the screw feeding device. A lower base 23 to which the chuck mechanism 19 is fixed is slidably inserted, and this lower base 23 is locked by a nut at the lower end of a rod of another telescopic cylinder 29 fixed to the support block 9. Automatic screw tightening machine with workpiece holding device.