JPH10328946A - Automatic thread fastening machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic thread fastening machine that can suckingly hold a screw in a correct position. SOLUTION: An automatic thread fastening machine is provided with a driver bit 9 rotatable receiving driving of a rotatory-drive source, a first suction sleeve 10 of hollow shape constantly including the driver bit 9 and movable integrally with the driver bit 9 and along the driver bit 9, a second suction sleeve 14 of hollow shape constantly including the first suction sleeve 10, and air suction mechanism provided in such a way as to suck air from the tip of each suction sleeve. The outer diameter of the first suction sleeve 10 is formed to be smaller than the head diameter of a sucked screw, and the inner diameter of the second suction sleeve 14 is formed in such a way as to be able to guide the screw head. The driver bit 9 is so arranged that its tip part is engaged with a screw driving hole when the screw is suckingly held to the first suction sleeve 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic screw tightening machine having a suction sleeve for sucking a screw by suctioning air from the tip.

[0002]

2. Description of the Related Art Conventionally, an automatic screw tightening machine disclosed in Japanese Patent Application Laid-Open No. 4-223883 has been generally used to fasten a screw to a work. Such a conventional automatic screw tightening machine has concentric suction sleeves having different inner diameters corresponding to two types of screws having different head diameters. These suction sleeves are connected to an air suction mechanism so as to perform air suction from the front end, and the outer suction sleeve can be moved along the inner suction sleeve, and is always at the front end side of the inner suction sleeve by a spring. Has been energized. The inner suction sleeve is movable along the driver bit by the operation of a reciprocating drive source such as a cylinder, and is always disposed so as to include the tip of the driver bit. With this configuration, a screw with a large head diameter is sucked into the outer suction sleeve and held in contact with the tip of the inner suction sleeve, and a screw with a small head diameter is sucked into the inner suction sleeve and held at the tip of the driver bit. Is held in contact with

[0003]

However, in the above-mentioned conventional automatic screw tightening machine, when a screw having a large head diameter corresponding to the outer suction sleeve is sucked and held, the head of the screw contacts the inner suction sleeve. However, at this time, the screw comes into contact with the outer suction sleeve and tilts, and is sucked and held by the inner suction sleeve as it is. In the subsequent screw tightening operation, the driver bit is engaged with the drive hole of the screw. However, there is a problem that the screws cannot be tightened and the screws cannot be tightened.

[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 capable of sucking and holding a screw in a correct posture.
In order to achieve this object, the present invention provides a driver bit having a tip end engageable with a driving hole of a screw fastened to a work and rotatable by being driven by a rotary driving source, and A hollow first suction sleeve movable integrally with the driver bit and movable along the driver bit; a hollow second suction sleeve always including the first suction sleeve; An air suction mechanism provided to suck air from the tip. The outer diameter of the first suction sleeve is formed smaller than the head diameter of the screw to be sucked, and the inner diameter of the second suction sleeve is formed to be able to guide the head of the screw. Further, the driver bit is arranged such that when the screw is attracted to the first suction sleeve, a distal end portion is engaged with a driving hole of the screw. Further, the distal end surface of the first suction sleeve is formed in a shape conforming to the upper surface of the head of the screw, and is configured to enhance the confidentiality at the time of screw suction.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1 and FIG. 2, reference numeral 1 denotes an automatic screwing machine, which includes a driver base 4 slidable along a guide 3 arranged on the front surface of a base 2. The driver table 4 is connected to a rod 5 a of a cylinder 5, which is an example of a reciprocating drive source disposed on the base 2, and is configured to be able to reciprocate upon receiving the operation of the cylinder 5. A motor 6, which is an example of a rotational drive source, is disposed on the driver base 4, and a transmission shaft 8 is connected to an output shaft of the motor 6 via a joint 7.
The transmission shaft 8 penetrates a suction unit to be described later, and a driver bit 9 is connected to a tip of the transmission shaft 8 so as to rotate integrally.

The driver bit 9 has a tip 9a which can be engaged with a driving hole of a screw head, and a pin 9b is fixed on the top of the tip 9a so as to protrude in a direction intersecting the axis. Supports the first suction sleeve 10 arranged so as to include the driver bit 9. The first suction sleeve 10 and the driver bit 9 are
The pin 9 is inserted into the elongated hole 10a provided in the first suction sleeve 10.
b are connected by fitting, and can be moved relative to the driver bit 9 by the length of the elongated hole 10a.

[0007] The first suction sleeve 10 is formed in such a shape that its front end surface matches the upper surface of the head of the screw to be held by suction, so that the internal confidentiality when the screw is held by suction can be enhanced. Is configured. In addition, this first
The suction sleeve 10 is constantly urged toward the distal end side of the driver bit 9 by a spring 11 inserted above the driver bit 9. The tip always projects slightly from the first suction sleeve 10. In addition,
The amount of protrusion of the driver bit 9 depends on the first suction sleeve 1.
When the screw is attracted to 0, the tip is set to an amount such that the tip 9a of the driver bit 9 matches the drive hole of the screw.

The suction unit 1, which is constantly urged toward the tip of the driver bit 9 by a spring 12, is attached to the transmission shaft 8.
3 are supported. The suction unit 13 is formed in a hollow shape so as to be able to guide the transmission shaft 8, and a distal end thereof is connected to a hollow second suction sleeve 14 which always includes the first suction sleeve 10 concentrically. Have been.
Further, a hose connector 15 to which a suction hose extending from an external air suction device (not shown) can be connected is fixed to the suction unit 13 so that air can be sucked through the hose connector 15. It is configured.

On the other hand, a chuck base 16 is connected to a lower end of the base 2, and a guide sleeve 17 is connected to the chuck base 16 so as to hang downward. The guide sleeve 17 guides the suction unit 13, and the leading end thereof has the driver bit 9.
The chuck unit 18 is connected to the lower part of the chuck. The chuck unit 18 includes a pair of chuck claws 19 that are urged to always close the movement path of the driver bit 9. The chuck claw 19 can hold a screw on the movement path of the driver bit 9. Holding hole 19a
Is formed, and a screw fed by air from a screw supply device (not shown) can be fitted.

In the automatic screw tightening machine 1, when the screw sent from the screw feeder (not shown) by air pressure is fitted and held in the holding hole 19a of the chuck 19, the cylinder 5 is operated. The driver base 4 starts lowering, and in response to this, the driver bit 9, the suction unit 13, and the first and second suction sleeves 10, 14 also lower integrally. Further, since the motor is driven at the same time, the driver bit 9 and the first suction sleeve 10 rotate integrally while descending.
In this state, the air suction device (not shown) operates and the second
Air suction is started from the tip of the suction sleeve 14, and air suction is also performed from the tip of the first suction sleeve 10 through the elongated hole 10a.

When the second suction sleeve 14 approaches the screw held by the chuck pawl 19, the screw is sucked while being guided by the second suction sleeve 14 on the periphery of the head. At this time, since the tip of the driver bit 9 slightly protrudes from the first suction sleeve 10, the tip of the driver bit 9 is made to enter the drive hole of the screw before the head of the screw contacts the first suction sleeve 10. Can be kept
It is possible to suck the screw while guiding the drive hole with the driver bit 9.

As described above, the screw sucked by the second suction sleeve 14 is sucked and held by the first suction sleeve 10, and at this time, the tip of the driver bit 9 coincides with the driving hole of the screw. Therefore, the screw has the upper surface of the head on the first suction sleeve 10.
In addition, the periphery of the head is supported by the second suction sleeve 14, and the drive hole is supported by the driver bit 9, so that the tip of the first suction sleeve 10 is suction-held in a correct posture. At this time, the distal end surface of the first suction sleeve 10 matches the upper surface of the head of the screw that is properly suction-held, so that the confidentiality in the first and second suction sleeves can be improved.

Thereafter, when the second suction sleeve 14 comes into contact with the surface of the work and stops, the first suction sleeve 10 is guided by this and moves forward to supply the screw held at the tip to the female screw position of the work. . At this time, since the driver bit 9 has already been rotated, the screw is tightened to the female screw. In addition, since the outer diameter of the first suction sleeve 10 is formed smaller than the head diameter of the screw, a work in which a female screw is formed in the back of a hole slightly larger than the head diameter of the screw is required. Even so, it is possible to make the first suction sleeve 10 enter the hole and securely tighten the screw. Further, since the outer diameters of the first and second suction sleeves 10 and 14 are different, it is also possible to suck and hold screws having different head diameters.

[0014]

As described above, in the automatic screw tightening machine of the present invention, the outer diameter of the first suction sleeve is smaller than the diameter of the head of the screw, and the inner diameter of the second suction sleeve is formed so as to guide the head of the screw. In addition, the driver bit is slightly projected from the first suction sleeve, and when the screw is sucked to the first suction sleeve, the tip of the driver bit is engaged with the drive hole of the screw. There is an advantage that the screw can be supported by the first suction sleeve, the second suction sleeve, and the driver bit, and the screw can be sucked to the first suction sleeve in a correct posture. In addition, for example, there is an advantage that the screw can be securely tightened even for a work in which a female screw is formed in the back of a hole having a diameter slightly larger than the head diameter of the screw. Further, since the distal end surface of the first suction sleeve matches the upper surface of the head of the screw,
Combined with the fact that the screw is sucked in the correct posture, the confidentiality inside the first suction sleeve can be enhanced, and there is an advantage that the screw suction can be accurately confirmed using, for example, a vacuum switch. .

[Brief description of the drawings]

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

FIG. 2 is a front view in which a part of a continuous part of the automatic screw tightening machine according to the present invention is omitted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic screwdriver 4 Driver stand 5 Cylinder 6 Motor 8 Transmission shaft 9 Driver bit 10 1st suction sleeve 14 2nd suction sleeve 16 Chuck base 18 Chuck unit 19 Chuck jaw

Claims (2)

[Claims] 1. A driver bit having a tip end engageable with a driving hole of a screw fastened to a work and rotatable by being driven by a rotation driving source, and including the driver bit at all times and integrally with the driver bit. And a hollow first suction sleeve movable along the driver bit;
An automatic screw tightening machine including a hollow second suction sleeve that always includes the first suction sleeve, and an air suction mechanism provided to suck air from a distal end of each of the suction sleeves. The outer diameter is formed smaller than the head diameter of the screw to be sucked, the inner diameter of the second suction sleeve is formed so that the head of the screw can be guided, and the driver bit is screwed to the first suction sleeve. An automatic screwing machine characterized in that it is arranged at a position where it engages with a driving hole of the screw when sucked. 2. The automatic screw tightening machine according to claim 1, wherein the distal end surface of the first suction sleeve has a shape matching the upper surface of the head of the screw.