JPH11156648A - Automatic screw fastener - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic screw fastener which can freely open and close holding claws and satisfactorily perform screw fastening. SOLUTION: A pair of holding claws 13 which can hold a screw are arranged on a moving passage of a driver bit 8 in a rotatable manner to a main body 12. Engagement members 16 are projected from the holding claws 13. An operation member 17 having operation pieces 17a, 17b, to be alternatively engaged with the engagement members 16 is arranged on the main body 12. The operation member 17 is reciprocated upon receiving operation of a cylinder 18. The operation pieces 17a, 17b are engaged with the engagement members 16, for closing or opening the holding claws 13.

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 for freely opening and closing a holding claw for holding a screw.

[0002]

2. Description of the Related Art Conventionally, various types of automatic screw tighteners have been used for fastening screws to a work. This type of automatic screw tightening machine is generally provided with a magnetized driver bit that can be rotated by being driven by a rotary drive source, and holding means that can hold a screw on a moving path of the driver bit. . The holding means includes a pair of rotatable holding claws, and the holding claws are urged by a spring or the like to be normally closed. Further, a holding hole is formed separately on the opposing surface of the holding claw, so that a screw sent from a screw supply device such as a feeder is fitted.

[0003]

In the above-mentioned conventional automatic screw tightening machine, the screw fitted and held in the holding hole of the holding claw is sucked and held with the movement of the driver bit, and is pushed out from the holding claw. However, at this time, the holding claw attempts to close by the bias of the spring before the screw is completely pushed out to the front of the holding claw, so the screw is flipped off by that force,
Problems such as screws dropping out of the driver bit have occurred.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an automatic screw tightening machine which can freely open and close a holding claw and can perform a good screw tightening. And In order to achieve this object, the present invention has a driver bit configured to be rotatable under the drive of a rotary drive source and reciprocally movable in the axial direction under the drive of a reciprocal drive source. A holding means configured to be able to hold the screw is arranged on the moving path. The holding means includes a pair of holding claws rotatably connected to the main body, and opening and closing means for rotating the holding claws.

The opening / closing means has an engaging member projecting from the holding claw, and a closing operation piece at one end capable of engaging with the engaging member to close the holding claw, and at the other end. An operating member having an operating member for expanding which can open the holding claw by being inserted between the engaging members, and a reciprocating drive for moving the operating member so that each operating member is alternately engaged with the engaging member. And a source.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5, reference numeral 1 denotes an automatic screwing machine having a driver table 4 movable along a guide 3 attached to a base 2. The driver base 4 is connected to a rod 5a of a cylinder 5 which is an example of a reciprocating drive source disposed on the base 2, and a motor 6 which is an example of a rotary drive source is mounted on an upper surface thereof. An output shaft 6a of the motor 6 has a connecting shaft 7
The driver bit 8 is connected via the
Is driven so that the driver bit 8 rotates. The driver bit 8 has been magnetized by being exposed to a magnetic field in advance, and has a hexagonal cross section at its tip end so that a screw with a hexagonal hole can be mainly fastened.

A chuck base 9 is disposed below the guide 3 under the driver base 4, and the chuck base 9 can hold a screw on a moving path of the driver bit 8. Holding means 10 are arranged. The holding means 10 includes a hollow guide sleeve 11 attached to the chuck base 9, a main body 12 provided at the tip of the guide sleeve 11, and a pair of holding claws 13, 13 rotatably attached to the main body 12. And this holding claw 1
Opening / closing means 14 for opening / closing 3, 3;
And a hose connector 15 attached diagonally to the hose.

The guide sleeve 11 encloses the driver bit 8, and a guide path 12a is formed in the main body 12 in communication therewith. The hose connector 15 is hollow inside. A hose (not shown) extending from a screw supply unit (not shown) such as a feeder is connected to one end of the hose connector 15. It is configured to guide to 12 guide paths 12a.

The holding claws 13, 13 are urged by a spring or the like so as to be always closed, and a holding hole 13a communicating with the guide path 12a is formed on the opposing surface thereof. The holding hole 13a is formed on the moving path of the driver bit 8, and the vicinity of the tip is
The diameter of the screw is reduced to a diameter that allows the threaded portion of the screw to pass and the head to be impermeable, so that the head of the supplied screw can be locked and fitted and held.

The opening / closing means 14 includes an engaging member 16 having an inverted V-shape formed by dividing the holding claws 13, 13, an operating member 17 engageable with the engaging member 16, and the operating member 1.
7 and a cylinder 18 to which a rod 18a is connected. The operating member 17 has a closing operation piece 17a and an expanding operation piece 17b with the engaging member 16 interposed therebetween, and the closing operation piece 17a can be engaged with the outer peripheral inclined surface of the engaging member 16. Operating piece 17b
Has a shape that can be inserted into the opening side of the engaging member 16.

In the automatic screw tightening machine 1 described above, the screw supplied by air from the screw supply means is connected to the hose connector 15.
And the guide holes 12a reach the holding holes 13a of the holding claws 13 and are held there. At this time, the rod 18a of the cylinder 18 extends and the engaging member 16 of the holding claws 13, 13 is extended.
, The closing operation piece 17a of the operation member 17 is matched, whereby the holding claws 13, 13 are closed non-rotatably. Therefore, the holding claws 13, 13 are not pushed and opened even by the collision of the screw sent by the air pressure feeding.

When the screw is held on the holding claws 13, 13, and then the cylinder 5 is operated to advance the driver table 4, the driver bit 8 advances inside the main body 12, and It is pressed against the held screw.
Also at this time, since the closing operation piece 17a still matches the engagement member 16, the holding claws 13 and 13 do not rotate. Therefore, in this state, the motor 6 is driven for a predetermined time to rotate the driver bit 8. Then, the tip can be aligned with the hexagonal hole of the screw, and the screw can be sucked in the correct posture.

Thereafter, when the cylinder 18 operates to contract the rod 18a to move the operating member 17 upward, the closing operating piece 17a is disengaged from the engaging member 16, and instead the expanding operating piece 17a is moved. 17b is the engaging member 16
And move to push it away. As a result, since the holding claws 13 and 13 are rotated so as to be opened integrally with the engaging member 16, the held screw is used as the driver bit 8.
It is released while being adsorbed on the. The screw released in this manner is pushed out to the work by further advancement of the driver base 4, and is fastened when the driver bit 8 is rotated. However, since the holding claws 13, 13 are already open, the holding claw 13 is held. The problem that the claws 13 and 13 interfere with the screw attracted to the driver bit 8 and repel the screw does not occur.

As for the embodiment of the present invention, the following example can be considered in addition to the above-mentioned example to obtain the same effect. First, in the second embodiment, as shown in FIG. 6, the holding claws 23, 23 are urged to be always closed by the springs 24, 24, and the cam members are sandwiched between the holding claws 23, 23. The holding claw is opened and closed by reciprocating the holding claw.

In the embodiment of the present invention, a description has been given by taking as an example a driver bit whose tip portion is formed in a hexagonal cross section. However, this driver bit can be arbitrarily adjusted according to the screw to be tightened. Which can be selected,
The effect obtained is the same regardless of which one is selected.

[0016]

As described above, since the automatic screw tightening machine of the present invention has the opening and closing means for opening and closing the holding claws, the holding claws can be opened and closed by this, and the impact at the time of screw supply can be achieved. To prevent the screw from receiving the closing force of the holding claw when the holding claw expands or push out the screw. There are advantages such as being able to. Further, since the operating members having the expanding operation piece and the closing operation piece are arranged so as to be alternately engaged with the engaging members provided on the holding claws, the holding claws can be easily moved simply by reciprocating them. Can be opened and closed, and the opening of the holding claw can be easily adjusted by replacing the operating member.

[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 side view of a main part of the automatic screw tightening machine according to the present invention.

FIG. 4 is an enlarged partial cutaway sectional view of a main part of the automatic screw tightening machine according to the present invention.

FIG. 5 is an essential part enlarged side view showing a state where a holding claw of the automatic screw tightening machine according to the present invention is opened.

FIG. 6 is an explanatory view showing a second embodiment of the automatic screw tightening machine according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic screwdriver 6 Motor 8 Driver bit 10 Holding means 14 Opening / closing means 16 Engaging member 17 Operating member 17a Closing operation piece 17b Expanding operation piece 18 Cylinder

Claims (2)

[Claims] A driver bit configured to be rotatable under the driving of a rotary driving source and reciprocally movable in an axial direction by an operation of a reciprocating driving source, and a screw is provided on a moving path of the driver bit. An automatic screw tightening machine having a holding means configured to be capable of holding, wherein the holding means includes a main body capable of guiding the driver bit, and a pair of holding claws rotatably connected to the main body. An automatic screwing machine comprising: opening and closing means for closing or expanding the holding claw. 2. The opening / closing means includes an engaging member projecting from each of the holding claws, and a closing operation piece which can be engaged with the engaging member to close the holding claw at one end, and at the other end. Is an operating member having an operating member for expanding which can open the holding claw by being inserted between the engaging members; and moving the operating member so that the operating members are alternately engaged with the engaging member. 2. The automatic screwing machine according to claim 1, further comprising a reciprocating drive source for causing the reciprocating drive.