JP3206878B2 - Chuck unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck unit for temporarily holding a supplied screw on a moving path of a screw tightening bit such as an automatic screw tightening machine.

[0002]

2. Description of the Related Art Conventionally, for example, an automatic screw fastening machine for fastening a screw to a work is generally provided with various chuck units for temporarily holding a screw on a moving path of a screw fastening bit such as a driver bit. This type of chuck unit generally has a chuck body capable of guiding a screw tightening bit, and a pair of chuck claws urged in a direction in which the tip is always closed are attached to the chuck body so as to be openable. . The chuck body is also provided with a supply pipe that is always in communication with the chuck pawl. A hose extending from a feeder that supplies the screw is connected to the supply pipe, and the screw that is air-fed from the feeder is connected to the chuck pawl. It is configured to be able to be supplied.

The chuck unit supplies and holds a screw, which is fed by air from a feeder, to a holding hole of the chuck claw through a supply pipe. In this chuck unit, the impact of the screw when the screw is supplied causes the chuck claw to move. There is a problem that the screw cannot be properly held by expanding the screw.
A chuck unit as disclosed in No. 9639 has been proposed. As shown in FIG. 6, the chuck unit has pins 22 and 2 on a pair of chuck claws 21 and 21, respectively.
2 and a pin pressing plate 23 which engages with the pins 22 and 22 to fix the chuck claws 21 and 21 so that the chuck claws 21 and 21 cannot be opened is provided. Air cylinder 2 to be moved to a position where it engages with
4 is provided.

[0004]

SUMMARY OF THE INVENTION
In the chuck unit as shown in No. 39, in addition to the basic components of the chuck unit such as a chuck claw and a supply pipe, components such as a pin, a pin pressing plate, and an air cylinder are required. And the cost of these components increases the cost. Also, in order to switch the chuck pawl between the openable state and the unspreadable state, the pin pressing plate must be operated by the operation of the air cylinder, so that a separate control means for the air cylinder is required. In addition, the problem in terms of price becomes more serious, and the timing at which the chuck jaws cannot be expanded may be out of order. There are also problems such as not having.

[0005]

According to the present invention, there is provided a chuck body capable of guiding a screw tightening bit rotatably and reciprocally movable by driving a rotary drive source, and the chuck body has an opposing surface. A pair of chuck claws, which are always urged in the closing direction and have a holding hole capable of holding a screw on the moving path of the screw tightening bit on the opposing surface, are arranged,
In the chuck unit, a supply pipe of a screw which is always in communication with the holding hole and is rotatable by being pushed by the movement of the screw tightening bit is disposed on the chuck claw. The supply pipe is formed in a shape that acts as a locking part that engages with the engagement part when the supply pipe communicates with the holding hole. It is characterized by being. The engaging portion protrudes from a surface of the chuck claw facing the supply pipe tip surface, and has a shape in which the opposed surfaces are joined to each other when the chuck claw is in a closed state. It is preferable that the claw is cut out so as to be able to engage with the engagement portion when the claw is in a closed state. Further, it is preferable that a tip end surface of the supply pipe on the chuck claw side is formed into an inclined surface having an angle that does not contact an engagement portion of the chuck claw when the supply pipe rotates.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4, reference numeral 1 denotes a chuck unit which is used by being attached to a tip portion of an automatic screwing machine. An automatic screw tightening machine (not shown) is a general one having a screw tightening bit 2 such as a driver bit and a box bit which are rotated by driving a rotary drive source (not shown) such as a motor, such as an XY mobile robot. Is connected to a reciprocating drive source (not shown) such as a positioning unit (not shown) and a cylinder, and is configured to move to a predetermined position and perform a screw tightening operation at that position.

The chuck unit 1 is an example of a headed bar-shaped member supplied from an external feeder (not shown) in the axial movement direction of the screw tightening bit 2 of the automatic screw tightening machine as described above. It has a chuck body 4 for temporarily holding the screw, which is attached to the base member 3 of the automatic screw tightening machine and can be operated integrally therewith. A guide hole 4a for guiding the screw tightening bit 2 is formed through the chuck body 4, and a pair of chuck claws 5, 5 having a holding hole 5a communicating with the guide hole 4a at the tip. A supply pipe 6 to which a hose 10 extending from the feeder is connected is arranged.

The chuck claws 5 and 5 are attached to the chuck body 4.
It is arranged so as to be able to expand with the mounting pin 5b as a fulcrum, and is normally kept closed by the bias of the spring 7. Also, the holding holes 5a of the chuck claws 5 are provided.
Has a configuration in which it is divided and formed on the opposing surface, and forms a hole space communicating with the guide hole 4a only when the chuck claws 5, 5 are in a closed state. Further, the engaging portions 8 are integrally formed with the chuck claws 5 and 5. The engaging portion 8 is divided and formed on the end face of the chuck claws 5 and 5 on the entrance side of the holding hole 5a, and when the chuck claws 5 and 5 are closed, the opposing surfaces are joined to form a rectangular parallelepiped shape. Is configured.

On the other hand, the supply pipe 6 is rotatably attached to the chuck body 4, and the tip portion is always positioned so as to intersect the guide hole 4a by the bias of the spring member 6a. And is configured to communicate with the entrance of the holding hole 5a of the chuck claws 5, 5. Also,
The supply pipe 6 is provided with a locking portion 9 for engaging with the engaging portion 8 of the chuck claws 5, 5. This locking portion 9
When the supply pipe 6 is connected to the holding hole 5a of the chuck claws 5, 5, the tip of the supply pipe 6 is cut out in a rectangular shape so that the engagement portion 8 can be engaged. 8 to support the chuck claws 5 and 5 so that they cannot be opened. Furthermore, this supply pipe 6
Is formed into an inclined surface 6b set at an angle having a predetermined gap with the entrance end surface of the holding hole 5a of the chuck claws 5, 5, and a portion where the locking portion 9 is not formed during rotation is engaged. It is configured not to come into contact with the joint 8.

In the chuck unit 1 having the above-mentioned structure, when the feeder is operated, the screw is fed by air through the hose 10. At this time, the supply pipe 6 is at a position communicating with the holding holes of the chuck claws 5, 5 as shown in FIG. Is supported so that it cannot be expanded. In such a state, even if the screw fed by air pressure reaches the holding hole 5a of the chuck claws 5, 5 through the supply pipe 6, the impact may cause the chuck claws 5, 5 to expand. The screws are securely received by the chuck claws 5 and 5 and are properly held in the holding holes.

When the screws are held by the chuck claws 5, 5,
The screw tightening bit 2 advances along the guide hole 4a due to the operation of the reciprocating drive source or the like, and pushes the tip end of the supply pipe 6 to rotate it as shown in FIGS. 5 (b) and 5 (c) to guide the screw. It is separated from the position intersecting with the hole 4a. As a result, the engaging portion 8 and the locking portion 9 are separated from each other, and the chuck claws 5, 5 can be opened. Accordingly, the chuck claws 5, 5 are pushed open with the advance of the screw tightening bit 2, and the screw can be opened on the work to perform the fastening operation. Then, after the screw fastening operation is completed, the screw 2 is retracted, so that the chuck claws 5 and 5 and the supply pipe 6 are sequentially rotated to return to a state where screws can be supplied to the chuck claws 5 and 5. At the same time, the engaging portion 8 and the engaging portion 9 are re-engaged to support the chuck claws 5, 5 in a state where they cannot be opened.

[0012]

As described above, in the chuck unit of the present invention, the engaging portion formed separately on the chuck pawl and the engaging portion notched at the upper end of the supply pipe engage with each other to expand the chuck pawl. Because it is configured so that opening is impossible, it does not require components such as pins, pin pressing plates, and air cylinders as in the past, and the basic configuration of a conventional chuck unit such as a chuck claw and a supply pipe is used. It is possible to obtain a configuration in which the expansion of the chuck pawl is restricted only by the components to be formed, and it is possible to extremely simplify the configuration of such a chuck unit, and to restrict the expansion of the chuck pawl by operating the cylinder. There are advantages such as a significantly lower cost as compared with the conventional chuck unit. Further, since the supply pipe is rotated by the advancement of the screw tightening bit, and the engagement between the engaging portion and the locking portion is released, the expansion of the chuck claw can be naturally controlled according to the screw tightening operation. There is no need for any control means to regulate the expansion of the chuck jaws, and the timing of controlling the expansion of the chuck jaws is excellent.The chuck jaws are securely closed when screws are supplied, and the screws that are fed by air are securely chucked. There are advantages such as providing a chuck unit that can be received by the claw.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chuck unit according to the present invention.

FIG. 2 is a front view of a chuck unit according to the present invention.

FIG. 3 is a side view of the chuck unit according to the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 2;

FIG. 5 is an operation explanatory view of the chuck unit according to the present invention.

FIG. 6 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 chuck unit 2 screw tightening bit 3 base member 4 chuck body 4a guide hole 5 chuck claw 5a holding hole 5b mounting pin 6 supply pipe 6a spring material 7 spring 8 engaging portion 9 locking portion 10 hose

Claims (3)

(57) [Claims] 1. A rotatable and reciprocating device driven by a rotary drive source.
A chuck body movably provided for guiding a screw tightening bit, the chuck body being urged in a direction in which an opposing surface is always closed and having the screw tightening bit on the opposing surface;
A pair of chuck pawls the screw holding hole capable of holding formed in the moving path of the bets placed, the holding in the chuck claws
Always communicating with the hole and with the movement of the screw tightening bit
In a chuck unit in which a supply pipe of a screw that can be rotated by being pressed by this is arranged , an engagement portion is divided and formed at a position facing the supply pipe tip of the chuck pawl , while the tip of the supply pipe is Offering
Engage with the engaging part when the supply pipe communicates with the holding hole
A chuck unit characterized in that it is formed in a shape that acts as a locking portion that engages . Wherein the engaging portion is a shape of bonding together the opposed surfaces when the surface opposite to the supply pipe leading end face of the chuck claws protrude, in a state where the chuck claws are closed, whereas the supply
The chuck unit according to claim 1, wherein a tip of the pipe is cut out so as to be able to engage with the engaging portion when the chuck pawl is in a closed state. 3. A tip surface of the supply pipe on the chuck claw side is provided with a rotating
Angle of inclination that does not touch the engaging part of the chuck claw when moving
The chuck unit according to claim 1, wherein the chuck unit is formed on a surface .