JP2000005948A - Automatic screw tightening machine - Google Patents

Abstract

(57) [Summary] [Problem] Supply to a narrow place while holding a screw stably,
Provided is an automatic screwing machine capable of fastening. According to the present invention, a driver bit (8) rotatable by a motor is provided, and a suction sleeve (19) that always includes the driver bit (8) is biased toward the tip end of the driver bit (8) so as to be able to move forward and backward. It is arranged so that the screw before tightening can be suction-held by performing air suction from the suction sleeve 19. The suction sleeve 19
Two flank surfaces 21 are formed opposite to each other at the tip end of the work so that the suction sleeve 19 can enter the groove of the work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic screwdriver for fastening a screw to a work, and more particularly to an automatic screwdriver having a suction sleeve for suction-holding a screw.

[0002]

2. Description of the Related Art Conventionally, an automatic screw tightening machine generally includes a driver bit which rotates by being driven by a rotary drive source such as a motor, and a suction sleeve which always contains the driver bit. ing. In this automatic screw tightening machine, the suction sleeve is always urged toward the tip end of the driver bit by a spring or the like, and communicates with the inside to connect an air suction device. At the time of screw tightening, air is previously suctioned from the tip of the suction sleeve in response to the operation of the air suction device, and the screw is sucked and held inside by the air suction.

[0003]

However, in the conventional automatic screw tightening machine described above, for example, a work 50 in which a screw tightening position 52 is provided at a bottom 51a of a slot 51 as shown in FIG. If the screw is to be fastened, the circumferential surface of the suction sleeve interferes with the groove, so that there is a problem that the screw cannot be approached to the tightening position. In order to deal with such a problem, the driver bit itself is usually magnetized, and a means for attracting and holding the screw is taken, but in this case, the driver bit is held at the tip of the driver bit by the action of machine vibration, external force, etc. In many cases, the set screw is tilted, which causes a problem that the screw cannot be stably held in a correct posture.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide an automatic screw tightening machine capable of stably holding a screw and supplying and fastening a narrow place. . In order to achieve the above object, the present invention provides a driver bit that can be rotated by being driven by a rotary drive source such as a motor, and biases a suction sleeve that always includes the driver bit toward the tip of the driver bit. The present invention relates to an automatic screw tightening machine which is arranged so as to be able to move forward and backward and connects this suction sleeve to an air suction device, wherein a relief surface is formed at a predetermined position on an outer circumferential surface of a tip portion of the suction sleeve. It is characterized by. Preferably, the suction sleeve is configured to be rotatable about the axis of the driver bit, and the flank is preferably formed parallel to two surfaces.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3, 1 is an automatic screwing machine, 2 is an upper bracket 3 on an upper portion of a base 3.
3A is an air cylinder as an example of a reciprocating drive source installed in a.
The air cylinder 2 is installed so that its rod 2a is directed vertically downward, and along the guide shaft 4 passed between the upper bracket 3a and the lower bracket 3b below the base 3 at the tip of the rod 2a. A slidable driver base 5 is connected. A driver 6 having an output shaft 6b that is rotated by driving a motor 6a is mounted on the driver base 5. A driver bit 8 is connected to an output shaft 6b of the driver 6 via a connection shaft 7. Have been. The driver bit 8 has a cross-shaped cross-shaped tip that can be engaged with a driving hole in the screw head, and receives the rotation of the output shaft 6b and the connection shaft 7 by the driving of the motor 6a. It rotates together with them.

A chuck base 9 is fixed to the lower end of the guide shaft 4, and the chuck base 9 is fed from an external screw supply device (not shown) on the movement path of the driver bit 8. A chuck unit 10 for holding a screw is connected. This chuck unit 10
Is a chuck body 11 containing a suction sleeve described later.
The chuck body 11 is rotatably connected to a pair (only one side is shown in the drawing) of a pair of chuck claws 12 each having a holding hole 12a into which a screw can be fitted on an opposing surface. . The chuck claw 12 is constantly urged by a spring (not shown) so that the opposing surfaces thereof are kept in contact and closed. A sleeve-shaped connecting member 13 capable of connecting a screw feeding hose (not shown) extending from a screw feeding device is connected to the chuck body 11, and a rotating pipe communicating with the connecting member 13. 14 are rotatably connected. This rotating pipe 1
Numeral 4 is constantly urged to communicate with the holding hole 12a of the chuck claw 12, and is configured to be able to guide the screw fed from the feeding hose to the holding hole 12a.

A hollow guide sleeve 15 is fixed to the lower surface of the driver base 5, and a sliding sleeve 16 is slidably engaged with the guide sleeve 15 so as not to fall off the guide sleeve 15. Is inserted. The sliding sleeve 16 is constantly urged downward by a spring 17 which is compressed and accommodated in the guide sleeve 15, and has a suction sleeve having an inner diameter capable of guiding a screw head via a connecting sleeve 18 at the end thereof. 19 are connected.

The suction sleeve 19 is connected to the connecting sleeve 1.
8, through which an air suction unit (not shown) such as a vacuum pump connected to the sliding sleeve 16 via an air hose 20 is actuated so that air can be sucked from the distal end. It is configured. Also,
Two flank surfaces 21 and 21 are formed at opposite positions on the outer cylindrical surface at the distal end of the suction sleeve 19, so that the suction sleeve 19 can enter a groove having a width smaller than the diameter of the outer cylindrical surface of the suction sleeve 19. Have been. The connecting sleeve 18 is held by screwing a screw portion 18a at one end into the tip of the sliding sleeve 16 and tightening a nut 18b screwed to the screw portion 18a. By rotating the sleeve 18,
The positions of the flank surfaces 21 and 21 of the suction sleeve 19 integrally screwed to the tip can be adjusted.

The above-mentioned automatic screwing machine is mainly used by being attached to a predetermined work station on a conveyor line, and in particular, the bottom 5 of a groove 51 shown in FIG.
Work 5 in which a screw tightening position 52 is provided in 1a
It can adapt to zero. When such a work 50 is sent to the conveyor line and positioned at a predetermined position below the driver bit 8, a screw is fed from the screw feeder to the chuck unit 10 and held. The screw is air-fed from the screw feeding device through a screw feeding hose, reaches the holding hole 12a of the chuck pawl 12 from the connecting tool 13 through the rotating sleeve 14, and is fitted and held therein.

When the screw is held on the chuck pawl 12 as described above, the driver bit 8 starts to move down by the operation of the cylinder 2 and lowers the suction sleeve 19 and the driver bit 8 together. Air suction has already been started from the distal end of the suction sleeve 19 by the operation of the air suction unit. Thus, in the lowering process, the screw held by the chuck claw 12 is sucked and held by the suction sleeve 19. After that, the suction sleeve 19 pushes the chuck pawl 12 forward and advances, and can enter the groove 51 of the work 50 because the flank 21 is provided, so that the front end can contact the bottom 51a. When the suction sleeve 19 abuts on the work 50 in this manner, the guide sleeve 15 slides along the sliding sleeve 16, whereby the driver bit 8 advances in the suction sleeve 19 and removes the screw being sucked. The work 50 is pushed out to the tightening position 52 at the time of rotation, and is rotated by the drive of the motor 6 a, and the pushed out screw is fastened to the work 50.

In the above description, the work in which the screw tightening position is provided at the bottom of the groove has been described. However, if the automatic screw tightening machine according to the present invention is used, not only in such a groove but also in the screw, Screws can be satisfactorily fastened to a work having an obstacle such as a wall adjacent to the fastening position.

[0012]

As described above, in the automatic screw tightening machine of the present invention, since two flank faces are formed at positions opposite to the outer cylindrical surface of the suction sleeve, the screw tightening position is provided on the bottom surface of the groove. The suction sleeve can be brought close to the work even when it is installed or when it is provided adjacent to the wall, and the screw is reliably supplied to the work tightening position.
There are advantages such as being able to be fastened. In addition, by rotating the suction sleeve, the position of the two chamfers can be freely adjusted, and there is an advantage that various types of workpieces can be handled.

[Brief description of the drawings]

FIG. 1 is an enlarged partial cutaway sectional view of a main part of an automatic screwing machine according to the present invention.

FIG. 2 is a front view of the automatic screw tightening machine according to the present invention.

FIG. 3 is an enlarged perspective view of the vicinity of a suction sleeve in the automatic screw tightening machine according to the present invention.

FIG. 4 is a perspective view showing an example of a work.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic screwing machine 2 Air cylinder 5 Driver stand 6 Driver 6a Motor 8 Driver bit 10 Chuck unit 12 Chuck jaw 18 Connecting sleeve 19 Suction sleeve 21 Relief surface

Claims (3)

[Claims] 1. A driver bit rotatable in response to the driving of a rotary drive source is provided, and a suction sleeve which always contains the driver bit is urged toward the tip of the driver bit so as to be capable of moving forward and backward. An automatic screwing machine comprising a sleeve connected to an air suction device, wherein a flank is formed at a predetermined position on an outer circumferential surface of a tip portion of the suction sleeve. 2. The automatic screw tightening machine according to claim 1, wherein the suction sleeve is configured to be rotatable around the axis of the driver bit. 3. The automatic screwing machine according to claim 1, wherein the flank is formed parallel to two surfaces.