JPH09225755A - Automatic screw tightening machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate bending of a feed hose to feed a screw to a chuck claw. SOLUTION: A screw guide passage 17 communicating with a chuck claw 16 located on a box bit moving passage of a driver unit 6 is provided, and pipe 19 to which a feed hose extending from a screw feeding device is connected to the screw guide passage 17. The pipe 19 is extended parallel to the axis along tie driver unit 6, and the feed hose can be prevented from being bent in the vicinity of the driver unit 6 by providing the pipe 6, and the mutual interference of the feed hose can be prevented when the driver unit 6 is of multi-spindle type. Screws can surely be fed by preventing the feed hose from being deformed even when the chuck claw 16 is moved to a narrow position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic screw tightener for tightening a screw on a work.

[0002]

2. Description of the Related Art Conventionally, an automatic screw tightening machine 50 as shown in FIG. 7 is generally known as a means for fastening a screw to a work. This automatic screw tightening machine 50 is a driver capable of raising and lowering a screw tightening tool 52 that is rotated by driving a rotary driving source 51 such as a motor, for example, a driver unit 53 including a driver bit, a box bit, etc., by driving an elevation driving source 54. A chuck unit 56 for holding a screw is arranged on the movement path of the screw tightening tool 52 of the driver unit 53. The chuck unit 56 of the automatic screw tightener 50 is configured to constantly close the chuck body 57 and arrange a pair of chuck claws 58. The chuck claw 58 guides and holds a screw in the closed state. Holding holes (not shown) having possible shapes are formed separately. Further, the chuck body 57 is provided with a screw guide path 59 which is always in communication with the holding hole of the chuck claw and projects obliquely upward, and a feed hose 60 extending from a screw supply device (not shown) is connected thereto. Then, the screw can be delivered to the chuck claw 58.

[0003]

In the above automatic screw tightener, since the screw guide passage is provided in the chuck body so as to project obliquely upward, when the feeding hose extending from the screw supply device is connected, the screw guide passage is connected. A curved portion bulging in the protruding direction is generated, and this curved portion interferes with the problem that the screw cannot be tightened in a narrow position. Also, with the intention of expanding the screw tightening range, when using multiple positioning robots such as articulated robots and mounting driver units on these positioning robots to perform screw tightening on multiple axes, There is also a problem that it becomes impossible to bring the driver units close to each other due to the interference of the curved portions.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a driver base that can be raised and lowered by the operation of an elevation drive source is provided, and a driver unit having a bit that is rotated by being driven by a rotary drive source is integrally arranged on the driver base. In addition, a chuck main body that can be raised and lowered integrally with the driver base and that can also be moved up and down independently is provided with a chuck pawl that holds a screw on the moving path of the bit, and a screw feeding device. In the automatic screw tightening machine provided with a screw guide path for guiding the screw to the chuck claw,
A pipe member that is always in communication with the screw guide path and through which a supplied screw can pass is provided parallel to the driver unit in the axis line. In the automatic screw tightening machine of the present invention, it is possible to form the tip of the driver base into a shape in which the width is gradually narrowed, and to position this at an arbitrary position in response to the operation of the positioning robot. .

[0005]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4, reference numeral 1 denotes an automatic screw tightening machine, which includes a screw shaft 3a rotatably guided by a base member 2 and a moving member 3b movable up and down with the rotation of the screw shaft 3a. The ball screw mechanism 3 is provided. The screw shaft 3a of the ball screw mechanism 3 is configured to rotate forward and backward under the drive of an AC servomotor 4 mounted on the upper surface of the base member 2. Further, a chamfered driver base 5 is fixed to the moving member 3b of the ball screw mechanism 3 so that the width thereof gradually narrows toward the tip side when seen in a plan view. The driver base 5 includes a driver unit 6 including a drive shaft 6b that is rotated by driving an AC servomotor 6a, which is an example of a rotary drive source, and a box bit 6c that is integrally connected to the lower end of the drive shaft 6b. is set up. The box bit 6c is a screw tightening tool generally used for tightening a hexagon bolt, and is configured to suck and hold the hexagon bolt by performing air suction from the tip end portion that engages with the head of the hexagon bolt.

Two slide shafts 7 extending vertically are connected to both sides of the base member 2 so as to be vertically slidable, and a chuck having a nose portion 8a at the lower end side of the slide shafts 7. The main body 8 is connected so as to move up and down integrally. The two slide shafts 7 are connected by a connecting member 9 near the upper portion of the base member 2 and are configured to move up and down integrally. Further, as shown in FIG. 5, the connecting member 9 has a built-in pinion gear 10 which is rotatably supported by a rotating shaft 10 a, and the pinion gear 10 moves with the vertical movement of the slide shaft 7. The rack 11 arranged on the front surface of the base member 2 meshes with the rack 11 to rotate. The rotation shaft 10a integrally supporting the pinion gear 10 is configured so that its rotation is braked by a brake mechanism 12 attached to the side surface of the connecting member 9.

The chuck body 8 is shaped so that its tip is hidden by the tip of the driver base 5 when viewed in plan. The chuck body 8 has a rod 1 extending upward.
A cylinder 13 provided with 3a is installed, and a rod 13a of the cylinder 13 is configured to pass through the driver base 5 and to be locked on the upper surface thereof. The chuck main body 8 is supported so as to be hung on the driver base 5 by thus locking the rod 13a of the cylinder 13 on the upper surface of the driver base 5, and can be lifted up and down integrally with the driver base 5, and the chuck main body 8 By moving the rod 13a back and forth, it is possible to move up and down independently of the driver base 5. Further, a cylinder 14 having a rod 14a extending downward is also connected to the chuck body 8. A roller member 15 is connected to the tip end of the rod 14a of the cylinder 14 via a link mechanism 15a as shown in FIG. It is configured to engage with the inside of the upper portion of the chuck claw 16 and to close the chuck claw in a state in which it cannot be expanded. Since the roller member 15 is supported by the parallel link 15a, the roller member 15 engages with the chuck claw 16 with a uniform force.

On the nose portion 8a of the chuck body 8,
A pair of chuck claws 16 are mounted on the moving path of the box bit 6c so as to be able to open. The chuck claw 16 is biased by a spring force so as to be always closed, and a holding hole 16a for holding a screw on the moving path of the box bit 6c is integrally formed on the opposing surface thereof. Further, a screw sent from an external screw supply device (not shown) is attached to the nose portion 8a by the chuck claw 1.
A screw guide path 17 for guiding to the holding hole 16a of No. 6 is arranged. The screw guide path 17 is provided in the driver unit 6
An inner hollow inlet side pipe 17a extending in parallel with the axis,
It is composed of an inner hollow outlet side pipe 17b which communicates with the inlet side pipe 17a and is normally communicated with the holding hole 16a of the chuck claw 16. Exit side pipe 17
The b is configured to be rotatable around a connection point with the inlet side pipe 17a as a fulcrum, and is configured to be pushed away by a box bit 6c that advances in the nose portion 8a.
Further, a pipe material 19 for connecting a feed pipe 18 extending from an external screw feeder is connected to the inlet side pipe 17a of the screw guide passage 17. The pipe material 19 is arranged along the driver unit 6 in parallel with the axis, and the upper end thereof extends through the driver base 5 to a position along the AC servomotor 6a of the driver unit 6.

Although not shown in the drawings, the automatic screw tightener of the present invention can be positioned at any position by connecting the base member 2 to a horizontal articulated robot or a positioning robot such as an XY moving table. It is configured, and moreover, a plurality of this is provided to form a multi-axis configuration. Further, the screw guide path 17 and the pipe material 19 are provided so as to be located on the back side of the driver unit 6 so that the driver units 6 having the multi-axis structure can be brought closest to each other.

The screw fed from the external screw feeder (not shown) through the feed pipe 18 is first made of the pipe material 19.
And it is supplied to the holding hole 16a of the chuck claw 16 through the screw guide path 17. At this time, the roller member 15 is fitted on the upper facing surface of the chuck claw 16, and thus the chuck claw 16 is kept in a state in which it cannot be expanded. Therefore, the chuck claws 16 are not pushed open by the collision of the supplied screws, and the screws can be reliably supplied. When the screw is supplied to the chuck claw 16 in this way, a positioning robot (not shown) operates to move the automatic screw tightener 1 above the workpiece fastening position. At this time, since the pipe material 19 and the screw guide path 17 are provided on the back side of the driver unit 6, and the tip end sides of the driver base 5 and the chuck body 8 are chamfered to narrow the width, the positioning robot is used. Even when a plurality of driven automatic screw tighteners are provided to form a multi-axis structure, these can be brought close to each other. Moreover, the pipe material 19 is the AC of the driver unit 6.
Since it extends to the position along the servo motor 6a, even when the driver units 6 approach each other, the phenomenon that the feed pipes 18 interfere with each other near the chuck body 8 is eliminated, and the driver unit 6 approaches smoothly. ,
It is possible to disengage.

After the positioning by the positioning robot is completed,
When the screw shaft 3a is normally rotated by the driving of the AC servomotor 4, the moving member 3b is lowered along with this, and the driver base 5 and the driver unit 6 are integrally lowered. Since the chuck main body 8 is in a state of being suspended on the driver base 5, it descends following the driver base 5 at this time, but when the tip of the chuck claw 16 reaches a position close to the surface of the workpiece, the brake is applied. The mechanism 12 is actuated to stop at that position. When the chuck jaws 16 are thus positioned, the pipe hose 19 is provided along the driver unit 6 so that the feeding hose is provided even if the tightening position of the bolt is a narrow position surrounded by the wall. It is possible to prevent the feed hose 18 from being damaged or deformed, since 18 does not contact the wall surface of the work.

Even when the tip of the chuck claw 16 reaches the surface of the workpiece and the lowering of the chuck body 8 is stopped in this way, the driver base 5 can be lowered, and therefore the box bit 6c.
Descends inside the nose portion 8a and contacts the bolt head held by the chuck claw 16. At this time, since the roller member 15 is still engaged with the upper facing surface of the chuck claw 16, the bolt is not pushed out by the box bit 6c, and if the box bit 6c is rotated, the bolt is fitted to the head portion of the bolt. Can be made. At this time, it is desirable that the driving of the AC servomotor 4 is temporarily stopped and the descent of the driver base 5 is stopped. Since air is sucked from the tip of the box bit 6c,
The bolt is sucked and held at the same time as it is fitted into the box bit 6c. After that, when the rod 14a of the cylinder 14 is retracted and the roller member 15 is retracted from the position where it is fitted to the chuck claw 16, the chuck claw 16 is in a state in which it can be expanded, and the bolt is chucked as the box bit 6c descends. It is pushed out from the claw 16 and fastened to the work.

[0013]

As described above, since the automatic screw tightener of the present invention is provided with the pipe material extending along the driver unit and parallel to the axis, the feeding hose extending from the screw feeder near the driver unit is curved. This makes it possible to position the chuck claw in a narrow position, and even when the chuck claw is positioned in a narrow position, screw clogging can be prevented and screw supply can be performed reliably. Is. In addition, the external appearance can be made very compact by reducing the protruding parts, and the risk of hitting a part of the human body during work is reduced.
Furthermore, by providing such a pipe material, and by making the tip side of the driver base and the tip side of the chuck body have a shape in which the width gradually narrows when viewed in a plan view, the automatic screw tightener receives the operation of the positioning robot. Even if multiple units are installed in a multi-axis configuration, the driver units can be brought as close as possible to each other, and the screw tightening positions are densely installed. However, it is possible to obtain the effect that the screw tightening work can be performed at the same time.

[Brief description of drawings]

FIG. 1 is a front view of an automatic screwing machine according to the present invention.

FIG. 2 is a cross-sectional view showing the internal configuration of the automatic screw tightener according to the present invention.

FIG. 3 is an enlarged plan view of the automatic screw tightener according to the present invention.

FIG. 4 is an enlarged bottom view of the automatic screw tightener according to the present invention.

FIG. 5 is an enlarged sectional view of an essential part showing the vicinity of the brake mechanism of the automatic screw tightener according to the present invention.

FIG. 6 is an enlarged cross-sectional view of essential parts showing the vicinity of chuck claws of the automatic screw tightener according to the present invention.

FIG. 7 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1 Automatic Screw Tightening Machine 2 Base Member 3 Ball Screw Mechanism 3a Screw Shaft 3b Moving Member 4 AC Servo Motor 5 Driver Stand 6 Driver Unit 6a AC Servo Motor 6b Drive Shaft 6c Box Bit 7 Slide Shaft 8 Chuck Body 8a Nose 9 Connecting Member 10 Pinion Gear 10a Rotating Shaft 11 Rack 12 Brake Mechanism 13 Cylinder 13a Rod 14 Cylinder 14a Rod 15 Roller Member 15a Link Mechanism 16 Chuck Claw 17 Screw Guide Path 17a Inlet Side Pipe 17b Outlet Side Pipe 18 Feed Hose 19 Pipe Material

Claims (3)

[Claims] 1. A driver base that can be raised and lowered by the operation of an elevation drive source is provided, and a driver unit having a bit that is rotated by receiving the drive of a rotary drive source is integrally arranged on the driver base, and is integrated with the driver base. Provided is a chuck body that can be raised and lowered and that can be moved up and down independently. A chuck claw that holds a screw on the moving path of the bit is arranged on this chuck body, and a screw sent from a screw supply device is guided to the chuck claw. In the automatic screw tightening machine provided with a screw guide path, a pipe material, which is in continuous communication with the screw guide path and through which a supplied screw can pass, is provided in parallel with the driver unit in the axis line. Fastener. 2. The automatic apparatus according to claim 1, wherein the tip of the driver base is formed into a shape in which the width is gradually narrowed, and the shape can be positioned at an arbitrary position in response to the operation of the positioning robot. Screw tightener. 3. A plurality of driver bases are configured so that they can be positioned at arbitrary positions in response to the operation of a positioning robot.
The automatic screw tightener according to claim 2, wherein the driver unit is configured with multiple axes.