JPH04300128A - Screw tightening device - Google Patents

Abstract

PURPOSE:To provide a screw tightening device which does not require a large scale device constitution but which can carry out screw tightening work to a work piece from the vertical and horizontal directions in a simple device constitution. CONSTITUTION:This is a screw tightening device 28 provided on a mobile means 1 with a degree of freedom to move at least in three axial directions of XYZ axes and to fix a screw 22 on a commodity, and the screw tightening device 28 is provided free to rotate (in the arrow T direction) on a flat surface specified with the XZ axis.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw tightening device, and more particularly to a screw tightening device used, for example, in a robot hand or the like, which is a moving means having degrees of freedom to move in at least three axes (X, Y, and Z axes).

0002

2. Description of the Related Art Screw tightening devices used in robot hands and the like have been known in the past, and various types have been used. FIG. 6 is an external view of a conventional screw tightening device, and FIG. 6(a) is called a vertical screw tightening device 29, and while it is attached to the robot hand 1,
After holding the screw 22 at the tip of the screw 2, the screw 22 is moved above the workpiece and the screw is tightened by the rotation of the motor 2.

Further, FIG. 6(b) is called a horizontal screw tightening device 30, in which a bit 12 is mounted on a base 27 as shown in the figure.
The screw 22 is held at the tip of the bit 12, and then the screw is moved to the side of the workpiece so as to face it, and the screw is tightened by the rotation of the motor 2. . FIG. 7 is an external view of an assembly process using both the vertical screw tightening device 29 and the horizontal screw tightening device 30, in which two workpieces 24 are fixed in parallel on the assembly stage 25 using fixing fittings 26. represents the case. The vertical screw tightening device 29 attached to the above-mentioned robot hand 1 moves freely to a set position on the work 24 to perform screw tightening work on the overhead portion of the work 24 arranged in this way. Screw tightening work on the side portions is performed by a horizontal screw tightening device 30.

0004

[Problems to be Solved by the Invention] However, in the assembly process shown in FIG.
9 and the horizontal screw tightening device 30 are required, and since the horizontal screw tightening device 30 cannot be moved into the space between the workpieces 24 in the figure, screw tightening from the direction of the arrow H in the figure is required. There was a problem that made it impossible to work. In addition, in order to perform the screw tightening work from the lateral direction on the workpiece 24 on the near side in the figure, a relative movement mechanism between the horizontal screw tightening device 30 and the workpiece 24 is required, which increases the installation area and requires large-scale work. There is a problem with the device configuration, and manual work is no longer required in such parts.

[0005] Therefore, the present invention has been made in view of the above-mentioned problems, and its purpose is to enable screw tightening work in vertical and horizontal directions to a workpiece with a simple device configuration, and to To provide a screw tightening device that does not require a large-scale device configuration.

[0006]

[Means to solve the problem] and

[Operation] In order to solve the above problems and achieve the purpose,
The screw tightening device of the present invention is provided on a moving means having a degree of freedom to move in at least three axial directions of the XYZ axes,
This is a screw tightening device for screwing a screw into an object, and by providing the screw tightening device so as to be rotatable on a plane defined by the XZ axis, it is possible to perform screw tightening work from the vertical and horizontal directions of the work. Work so that you can.

[0007] Also, preferably, a fixed base body attached to the moving means, a Y-axis body rotatably provided on the fixed base body rotatably about the Y-axis;
A rotating means that applies rotational force to the shaft and is provided on the fixed base body, a rotating base that is integrally provided on the Y-axis body, and a large bevel gear that is rotatably provided around the Y-axis body. a second small bevel gear that is rotatably held with respect to the rotating base and meshes with the large gear; a holding means movable in the longitudinal direction; a first holding means provided on the fixed base body and meshing with the large bevel gear;
It is configured to include a motor means having a small bevel gear, and functions to perform screw tightening work from the vertical and horizontal directions of the workpiece.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partially cutaway external perspective view of an embodiment of a screw tightening device. Referring to the figure, a screw tightening device 28 is detachably installed on the robot hand 1, which has a degree of freedom to move in at least the three axes of X, Y, and Z in the figure. The screw tightening device 28 is a screw tightening device for tightening the screws 28 in the direction of arrow T on the plane defined by the XZ axis in the figure.
By providing rotatability over 0 degrees, the workpiece can be rotated vertically,
This allows screw tightening work to be performed horizontally, diagonally below, or diagonally above.

For this purpose, the fixed base body 3 attached to the robot hand 1 has a shape that opens downward in the shape of a "U".
The shaft body 5 is provided so that the Y axis in the figure is the center of rotation. A rotary actuator 11 is provided at one end of the Y-axis body 5 and is a pneumatic rotary drive source that provides rotational force to the Y-axis body 5 and is provided on the fixed portion 3a of the fixed base body 3.

A bearing 4 is press-fitted into the other end of this Y-axis body 5, and as a result of the bearing 4 being held by the fixed base body 3, the Y-axis body 5 is in a state of being supported on both sides. Next, the Y-axis body 5 has a U-shaped opening facing upwards, and a rotating base body 8 (not shown) that is integrally fixed to the Y-axis body 5. It is fixed with a pin etc. As a result, as the rotation actuator 11 rotates, the rotation base body 8 is moved in the direction of arrow T on the plane defined by the XZ axis in the figure, and is made operable to stop after the movement. There is.

A large bevel gear 9 is rotatably provided around the outer circumference of the Y-axis body 5, and this large bevel gear 9 is connected to the motor 2 fixed on the fixed base body 3. It meshes with the first small bevel gear 6 fixed to the output shaft, and rotation of the motor 2 drives the large bevel gear 9 to rotate. on the other hand,
On the lower side opposite to the large bevel gear 9 driven as described above, the second small bevel gear 7 is rotatably held with respect to the rotating base body 8 and meshes with the large bevel gear 9. A bit body 12 is provided, and a screw 22 is attracted and held at the tip of the bit body 12. In this way, insert the screw 22 into the tube 1 at the tip of the bit body 12.
A holding mechanism is provided which is movable in the longitudinal direction of the bit body 12 in order to adsorb and hold it by negative pressure air sent through the bit body 12.

FIG. 2 is a cross-sectional view taken along the line W-W in FIG. This shows a configuration example. In FIG. 2, the bit 13 to which the second small bevel gear 7 is fixed at the upper tip portion is inserted into the bit support tube 16 which is fixed to the rotating base body 8 using a fixing screw 17. Afterwards, the E-ring 19 is set on the lower end surface of the bit support tube 16 as shown in the figure, and is rotatable by the bit support tube 16 and prevented from falling off. Further, a rubber O-ring 20 is preset inside the bit support tube 16 to prevent leakage of negative pressure air, which will be described later, for holding the bit by suction. Next, on the outer peripheral surface of this bit support tube 16, the bit body 2 is movable in the vertical direction and a rubber O-ring 20 is preset to prevent leakage of negative pressure air, which will be described later, for holding the bit by suction. In order to achieve this, a pin 18 provided on the bit body 2 is inserted into the vertical groove 16d of the bit support tube 16 to prevent rotation.

Furthermore, the rotating base body 8 and the bit body 1
A compression spring 15 is inserted between 2 and urges the bit body 12 downward. Bit body 1
A nipple 14a is provided on the side surface of the bit 13 so as to communicate with the groove 12m, and by guiding the negative pressure air sent through the tube 14 to the lower end of the bit body 12, the screw 22 is inserted into the tip threaded portion of the bit 13. It is designed to be held by suction at 13a.

Next, an example of the operation of the screw tightening device 28 described above will be described based on the assembly process external views shown in FIGS. 3 and 4. In FIG. 24 is fixed. A screw pallet 23 containing a large number of screws 22 is arranged near the assembly stage 25, and when the bit body 12 of the screw tightening device 28 attached to the robot hand 1 is in a substantially vertical position, Due to the operation of the mechanism,
One screw 22 is taken out from the screw pallet 23.

After this, in the case shown in (a) in the figure in which screws are tightened to the side surface of the workpiece 24, the rotation actuator 11 is operated to rotate the bit body 12 by 90 degrees. Then, the robot hand 1 is moved and screws are tightened to the side surface of the workpiece 24. Also, work 2
In the case shown in (b) in the figure in which screws are tightened to the top surface of the workpiece 2, the robot hand 1 is moved and
Tighten the screws on the side of 4.

Next, as shown in FIG. 4, when two pieces of workpieces 24 are installed in parallel, after taking out the screws 22 from the screw pallet 23 and rotating the bit body 12, 24, the screw tightening device 28 is moved down and the screw tightening operation on the side portion of the workpiece 24 is performed by the motor 2.
This is done by rotating the By attaching the screw tightening device 28 to the robot hand 1 as described above, the entire device can be configured in a very simplified manner.

[0017] In the above explanation, an example of the structure for rotating the bit body 12 from a vertical position to a horizontal position was described using a bevel gear, but it is needless to say that the configuration is not limited to this, and as shown in FIG. As shown in the modification of the screw tightening device 28, a flexible joint cable 31 may be connected to the output shaft of the motor 2, and the bit 13 may be fixed to one side of the flexible joint cable 31.

Furthermore, if a servo motor or a pulse motor with large detent torque is used to control the rotation of the bit body 12 in place of the rotation actuator 11 described above, the rotation of the bit body 12 can be controlled vertically and horizontally with respect to the workpiece 24. You will be able to tighten screws not only from the direction, but also diagonally, horizontally, up and down. Furthermore, if a reciprocating mechanism (piston) is provided in place of the motor 2 described above, it can be used as an article insertion device (inserter), and can also be used as a variety of other tools.
In place of the bit body 12, other tools may be provided.

[0019]

As explained above, according to the screw tightening device of the present invention, it is possible to perform screw tightening work in the vertical and horizontal directions of a workpiece with a simple device configuration, and the screw tightening device does not require a large-scale device configuration. A tightening device can be provided.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway external perspective view of an embodiment of a screw tightening device.

FIG. 2 is a sectional view taken along the line W-W in FIG. 1;

FIG. 3 is an external view of an assembly process of an operation example of the screw tightening device 28.

FIG. 4 is an external view of the process of assembling a plurality of works in an operation example of the screw tightening device 28.

FIG. 5 is an external view of a modified example of the screw tightening device 28.

FIG. 6 is an external view of a conventional screw tightening device.

FIG. 7 is an external view of a conventional assembly process using both a vertical screw tightening device 29 and a horizontal screw tightening device 30.

[Explanation of symbols]

1 Robot hand 2 Motor 3 Fixed base body 5 Y-axis body 6 1st small bevel gear 7 Second small bevel gear 8 Rotating base body 9 Large bevel gear 11 Rotation actuator 12 Bit body 13 bits 14 Tube 15 Compression spring 22 Screw

Claims (2)

[Claims] 1. A screw tightening device for screwing a screw into an article, the screw tightening device being provided on a moving means having a degree of freedom to move in at least three axial directions of the X, Y, and Z axes, the screw tightening device A screw tightening device characterized by being provided rotatably on a plane defined by a shaft. 2. A fixed base body attached to the moving means; a Y-axis body rotatably provided on the fixed base body about the Y-axis as a rotation center; a rotation means provided on the fixed base body; a rotation base integrally provided on the Y-axis body;
A bit comprising a large bevel gear rotatably provided around a shaft body, a second small bevel gear rotatably held with respect to the rotation base and meshed with the large gear; The bit has a holding means that sucks and holds the screw at the tip of the bit and is movable in the longitudinal direction of the bit, and a first small bevel gear that is provided on the fixed base body and meshes with the large bevel gear. 2. The screw fastening device according to claim 1, further comprising a motor means.