JP2877755B2 - Screw fastening device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw tightening device for automatically supplying screws, bolts and other screws necessary for assembling various machines and parts, and tightening the same to a work.
In particular, the present invention relates to a screw tightening device that stably sucks a screw into a suction pipe and eliminates a standby time of the suction pipe when tightening the screw, thereby improving work efficiency.

[0002]

2. Description of the Related Art FIG. 7 is a diagram showing a state of use of a main part of a conventional screw fastening device. In this figure, 1 is a feeder for conveying the screw 2, 3 is a suction pipe having a drive bit 4 therein, and 5 is a separation device 5 for separating the screw 2 conveyed from the feeder 1 to the suction pipe 3 side. is there.

The separating plate 6 of the separating device 5 is formed with a U-shaped cut 7 opened to the side, and is slidably fitted in the concave groove 9 of the block 8. When the cut 7 comes to a position corresponding to the groove 10 of the feeder 1, the screw 2 transported by the feeder 1 fits into the cut 7.
The fitted screw 2 moves to a position directly below the suction pipe 3 by the separation plate 6 sliding in the direction of the suction pipe 3. The suction pipe 3 descends and sucks the screw 2 into the inside. The suction pipe 3 moves right above the work 11 and descends, and is screwed by the drive bit 4.

[0004]

However, in the conventional screw tightening device, the suction pipe 3 descends from the state shown in FIG. 7A to suck the screw 2 therein as shown in FIG. The pipe 3 once rises slightly, and the separation plate 6 has to be retracted backward to wait until it can be lowered. Separation plate 6
This operation has a problem that the waiting time becomes longer due to the slow operation, and the efficiency of the screw tightening operation is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and a screw tightening device which stably sucks a screw into a suction pipe, eliminates a standby time of the suction pipe, and increases work efficiency. The purpose is to provide.

[0006]

According to the present invention, there is provided a screw tightening apparatus, wherein the pick chuck includes a stopper for selectively passing and blocking the screw conveyed to the tip of the feeder, and a screw at the tip of the feeder to the suction pipe side. It consists of a direct chuck that carries and an escape claw that stops the flow of the screw in place of the stopper when the stopper cannot shut off the screw.The direct chuck has a pair of fingers that pinch the screw at the tip of the feeder. An actuator for moving the suction pipe toward and away from the longitudinal Z-axis, and a first position in which the finger picks a screw at the tip of the feeder and a second position in which the picked screw is sucked into the suction pipe; With a slide device to move the stopper. Recess so as not to interfere with retraction when retracted in the first position and sucked into the suction pipe is formed.

[0007] The direct chuck can stably suck the screw at the tip of the feeder into the suction pipe. In addition, the direct chuck has a pair of fingers for picking a screw, and these fingers approach and separate from the Z axis in the longitudinal direction of the suction pipe. It can be carried out.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an overall perspective view of an embodiment of the present invention, FIG. 2 is a plan view of a pick chuck, FIG. 3 is a front view thereof, FIG. 4 is a left side view thereof, and FIG. FIG. 6 is a perspective view of the stopper.

The screw tightening device according to the present invention comprises a main body frame 2
Pick chuck 2 for gripping screw 21 at one end of zero
2, a rotary drum 23 is provided on the other end side, a feeder 24 is disposed between the pick chuck 22 and the rotary drum 23, and a suction pipe 26 that rises and lowers with a ball screw 25 stands upright from the feeder 24. ing.

The pick chuck 22 is arranged at the tip of the feeder 24 and has a stopper 27 for selectively passing and blocking the screw transported to the tip of the feeder 24.
And a direct chuck 28 that picks up the screw 21 sent to the tip of the feeder 24 and transports the screw 21 to a position directly below the suction pipe 26.
And the escape claw 29 for pressing the screw 21 so as not to protrude from the feeder 24 during carrying.

The stopper 27 is provided with a stopper plate 32 that rotates so as to close the tip of the feeder 24 at one end of a shaft 31 of a rectangular parallelepiped bearing 30. The tip portion 33 of the stopper plate 32 prevents the screw 21 from spilling out of the groove of the feeder 24. The concave portion 3 through which one finger 43 of the direct chuck adjacent to and separated from the distal end portion 33 can pass.
5 are formed (see FIG. 4).

At the other end of the shaft 31 of the bearing 30, a pushing plate 38 which is pushed down by a rod 37 of an air cylinder 36 and rotates the stopper plate 32 downward is attached. When the rod 37 is retracted, the shaft 31 is rotated reversely by a spring (not shown), and the stopper plate 3 is rotated.
2 returns to the original state.

The direct chuck 28 has an L-shaped substrate 39, and an actuator 40 is attached to the front end surface of the L-shaped substrate 39. When the actuator 40 supplies air to the element 41 on one side, the element 42 on the other side performs the same operation as this,
Element 4 on one side and the other side about feeder 24
1, 42 slide symmetrically in the Y-axis direction. Fingers 43 and 44 are attached to the lower portions of the elements 41 and 42 on one side and the other side, respectively.
1 can be picked and released.

A slide device 45 operated by air is attached to the upper part of the direct chuck 28 to slide the substrate 39 in the X-axis direction. Substrate 39
The range in which the fingers 43 and 44 of the direct chuck 28 are at least
The position is between the first position where the four screws 21 are picked and the second position where the suction pipe 26 sucks the picked screws.

A locking claw 47 for hooking the screw 21 from a lower end of one end of the lever 46 is attached to the escape claw 29 so as to protrude forward, and a rotor 48 is pivotally supported at an upper end of the one end. The other end of the lever 46 is pivotally supported on the main body frame 20 by a support shaft 49, and the lever 46 rotates about the support shaft 49. The escape claw 29 has a spring 50 at one end of the lever 46 (see FIG. 2).
And the locking claw 47 is normally
Is locked, but the direct chuck 2
When the shaft 8 retracts and its rear portion comes into contact with the rotor 48, the support shaft 4
Rotating around the center 9, the locking claw 47 separates from the screw.

The rotating drum 23 is mounted on the main body frame 20.
Is rotatably suspended on an H-shaped bracket 51 protruding from one end of the bracket. That is, the rotating drum 23 is suspended by the iron band 52 wound around the outer periphery of the drum 23 being attracted by a magnet (not shown) attached to the bottom surface of the bracket 51 and pressed against the rotating roller 53 to be suspended. It is rotated by a motor 54.

The feeder 24 is suspended from a vibrating body fixed to the bottom of the main body frame 20 via a leaf spring. The feeder 24 has one end portion of the rotary drum 2.
3, the other end extends to the pick chuck 22, and vibrates in the longitudinal direction of the main body frame 20 due to vibration of the vibrating body.

Negative pressure is applied to the suction pipe 26 by a pump (not shown), and the suction pipe 26 sucks the screw 21 conveyed by the direct chuck 28 from the lower end opening. The suction pipe 26 is moved Z by the ball screw 25.
Ascend and descend in the axial direction. That is, the drive motor 55 rotates in the forward and reverse directions to move the ball nut 56 up and down, and accordingly, the suction pipe 26 attached to the ball nut 56 also moves up and down in the Z-axis direction. A drive bit (not shown) is built in the suction pipe 26 and a drive motor 57
Turn to tighten the screws.

Next, the operation of the above configuration will be described. A large number of screws housed in the rotating drum 23 are scooped up by blades (not shown) provided on the inner peripheral wall of the rotating drum 23 as the rotating drum 23 rotates, and fall to one end of the feeder 24. Some inside is caught. The hooked screw 21 is conveyed to the distal end side of the feeder 24 by the vibration of the feeder 24 in the longitudinal direction. The screw 21 conveyed to the front end side is blocked by the front end portion 33 of the stopper plate 32 as shown by the solid line in FIG.

As shown in FIG. 2, the direct chuck 28 is at a first position for picking up the screw 21 at the tip of the feeder 24, and the fingers 43 and 44 are separated from each other. The locking claw 47 of the escape claw is separated from the screw 21 because the rear part of the direct chuck 28 pushes the rotor 48 backward. Therefore, it is the stopper 27 that stops the screw 21 from dropping from the tip of the feeder 24 in the state of FIG.

In order to carry the screw 21 from the state shown in FIG.
The feeder 2 is moved by bringing the pair of fingers 43 and 44 close to each other.
4, and pick up the screw 21 at both ends from both ends and slide the device 45.
Slides the substrate 39 to the second position. At that time, the process waits while rotated downward as indicated by the shaded two points of FIG. 4 so that the stopper 27 out of the way. This
The remaining screw 21 in the feeder 24 is escaped
Is stopped by a claw 29 so as not to fall.

When the direct chuck 28 carries the screw 21 to a position directly below the suction pipe 26, or enters a carrying operation, the ball screw 25 rotates to lower the suction pipe 26, and is pinched by the fingers 43, 44 of the direct chuck 28. I go to suck the screw 21 that has been put. While the suction pipe 26 is descending and the screws 21 of the fingers 43 and 44 are being suctioned, the stopper plate 32 rotates and returns to the original state (shown by the solid line in FIG. 4). However , since the rear part of the direct chuck 28 does not abut against the rotor 48 of the escape claw 29, the remaining screws 21 are stopped by the escape claw 29.

When the suction pipe 26 sucks the screw 21,
The mutual fingers 43 and 44 of the direct chuck 28
As soon as is opened, it is lowered and screwed to the work. Therefore, since the direct chuck 28 does not need to retreat to the first position at all, the screw tightening time can be reduced accordingly. The direct chuck 28 retreats to the first position while the fingers 43 and 44 are open while the suction pipe 26 is tightening the screw. When retracting, the concave portion 35 is formed at the tip of the stopper 27.
Therefore, the one finger 43 can be retracted without being hindered by the stopper 27, and unnecessary operation of the stopper 27 and time can be saved.

When the direct chuck 28 retreats to the first position, the rear portion of the direct chuck 28 abuts against the rotor 48 of the escape claw 29, so that the escape claw 29 separates from the screw 21 and the screw 21 that has been dammed is removed. After moving forward by one, the fingers 43 and 44 return to the state shown in FIG. Then, the above operation is repeated.

In the above-described embodiment, the structure has been described in which the fingers 43 and 44 of the direct chuck 28 are horizontally opened and closed by the actuator 40 in the Y-axis direction. However, the present invention is not limited to such a movement. The fingers 43 and 44 may rotate around the axis of the direction to pick and release the screw 21.

Also, the stopper plate 32 may be configured not to rotate about the axis in the X-axis direction but to rotate under the feeder 24 about the axis in the Y-axis direction. Good.

[0027]

According to the present invention, with the above-described structure, the suction pipe can be stably sucked by the screw of the feeder, and the standby time of the suction pipe can be eliminated to improve the working efficiency.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a screw fastening device according to an embodiment of the present invention.

FIG. 2 is a plan view of the pick chuck of the present invention.

FIG. 3 is a front view of the pick chuck of the present invention.

FIG. 4 is a left side view of the pick chuck of the present invention.

FIG. 5 is a perspective view of a direct chuck and escape claws of the present invention.

FIG. 6 is a perspective view of a stopper according to the present invention.

FIG. 7 is a partially used view of a conventional screw fastening device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Screw 22 Pick chuck 23 Rotary drum 24 Feeder 26 Suction pipe 27 Stopper 28 Direct chuck 29 Escape claw 35 Recess 40 Actuator 43 Finger 44 Finger 45 Slide device

Claims (2)

(57) [Claims] 1. A rotary drum is provided at one end of an apparatus main body, and a suction pipe for sucking and tightening a screw is provided upright at the other end, and a suction pipe is provided between the rotary drum and the suction pipe on the suction pipe side. In the screw tightening device with a pick chuck that supplies a screw to the suction pipe from the tip of the feeder, a feeder that transports the screw is provided, wherein the pick chuck selectively passes the screw that has been transported to the tip of the feeder. It comprises a stopper that shuts off, a direct chuck that carries the screw at the tip of the feeder to the suction pipe side, and an escape claw that stops the flow of the screw instead of the stopper when the stopper cannot shut off the screw. And a pair of fingers for picking up the screw of the suction pipe. And a slide device for moving the finger between a first position at which the finger picks the screw at the tip of the feeder and a second position at which the picked screw is sucked into the suction pipe. A screw tightening device, wherein a recess is formed so as not to disturb the retraction when the chuck sucks the screw into the suction pipe and retreats to the first position. The direct chuck acts on the escape claw so that the escape claw is disengaged from the feeder screw in the first position, and the escape claw stops the flow of the feeder screw in the second position. 2. The screw tightening device according to claim 1, wherein the screw tightening device operates.