JPH0335947A - screw tightening device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a screw tightening device, and more particularly to a screw tightening device equipped with a means for moving a screw tightening head and capable of automatically tightening screws.

2. Description of the Related Art In conventional screw tightening devices, as shown in FIG. A slide unit driven by a cylinder 19 is commonly used.

Problems to be Solved by the Invention However, when an air cylinder is used, the drive speed cannot be increased to match the feed speed during screwing, and there is a problem in that it is difficult to increase the speed of work.

Means for Solving the Problems In order to solve the above problems, the screw tightening device of the present invention has the following features:
A screw tightening device, a screw tightening head equipped with a tightening motor that rotationally drives it, and a mobile screwdriver that constitutes a linear sliding bearing that allows the screw tightening head to move in the distance direction relative to the workpiece. , a moving block B comprising the linear sliding bearing that transmits the power from the moving motor to the moving block A via two types of springs, and a driving control of the moving motor in accordance with the screw tightening process. A spring with a small spring constant connects the moving blocks, B, and the spring with a large spring constant is installed in such a way that it generates a tensile force when the moving blocks, B separates beyond a predetermined value. be.

According to the present invention, it is possible to move at high speed at position 4 where screw tightening is started, and when screw tightening is started ← koha.

The tip of the screw collides with the workpiece at high speed and stably bites the screw, and when the screw is tightened, an appropriate pressure is applied, automatically and at high speed for all types of screws. This allows highly reliable screw tightening.

Embodiment One embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

4. First, the overall structure of the screw tightening device will be explained with reference to FIG. In Fig. 2, 1 is a screw tightening head, and
It is supported to be movable in the horizontal direction by the axis moving means 2 and movable in the vertical direction by the Z-axis moving means 3. X-
The Y-axis moving means 2 is.

X @ table 4 top plate Y with movable body 6 movable in x direction
The Y-axis table 6 is configured to support a Y-axis table 6 that is movable in the direction, and the two-axis moving means 3 is attached to one end of this Y-axis table 6.
A guide member 7 and a screw supply stage 8 are attached.

The screw tightening head 1 is supported by a linear sliding bearing provided on the guide member 7 (14) so as to be movable up and down by a moving block 1o mounted on a guide rail 9, and also supported by a moving motor. A moving block B13 configured to be movable up and down by a feed screw 12 rotationally driven by 11
The spring B14 (b) connects the movable block 10 and Bt3 with a predetermined gap by a predetermined gap so as to generate a tensile force when the movable block 10 and Bt3 are separated by a predetermined distance of 1111 points. 10 and the other end is attached to Mobile Pro Nok B13.

16 is a drive phase motor that rotationally drives the screw tightening bit 16 of the screw tightening head 1.

1T is a main controller that controls the moving motor (not shown) of the X-Yfi moving means 2 and the moving motor 11 of the Z-axis moving means 3, and also controls the screw tightening control 8 to control the screw tightening pattern and screw tightening. 1. It is configured to output commands related to screw tightening conditions such as curvature, etc., and is configured to control the screw tightening roller 18 and the tightening motor 16 of the screw tightening head 1.

FIG. 1 shows the details of the configuration of the lifting/lowering drive unit of the screw tightening head 1 described in No. 611. The moving motor 11 is housed in a servo motor, and is attached with an encoder (not shown) for detecting its rotational position.

Next, the operation will be explained with reference to FIG.

In advance, the horizontal screw tightening position of the workpiece, the screw tightening conditions for the screw tightening head 1 such as the screw tightening pattern and tightening torque that will occur at that screw tightening position, and the screw tightening data described in "2" are programmed into the main program. The data is input to the controller 1 and recorded/iα.

When the start switch is pressed, the main controller 170
The X-τ axis moving means 2 operates according to the command to position the screw tightening head 1 at a predetermined position tl, and the screw tightening controller 18 moves the screw tightening head 1 according to predetermined screw tightening conditions.
The clamping field motor 15 is rotationally driven.

It descends at high speed from the position shown in FIG.

At the position shown in Fig. 3), the screw tip collides with the workpiece at high speed, and the screw tightening bit 16 escapes upward by the spring 14 (&) with a small spring constant, and the impact is relaxed and absorbed, and the impact is absorbed by the screw head. The bond cannot be broken either.

As the screw tightening joint 1 descends, the screw stably bites into the workpiece. Subsequently, the screws are tightened in the grooves shown in Figure 3(C), and the screws are tightened with high reliability by the spring 14(b) designed to provide an appropriate pressing force during tightening. Realized.

As described above, according to this embodiment, after the screw tightening bolt is stably engaged with the screw head, it is lowered at high speed at the screwing position 1, and then the spring constant is reduced to a small instantaneous impact 1 and expropriation. The structure of the lifting drive part has a spring constant of 2, which continuously changes as , and generates the appropriate pressure for screw tightening, so that the screw bites into the workpiece stably, and the screw tightens with stable tightening torque. This enables automatic screw tightening to be performed reliably and at high speed using χI for all types of screws.

In the above embodiment, the spring constant is 1. Although two separate springs are shown to have two types of springs, , and , they are not limited to those shown in this embodiment.

The components are: (1) A single spring with multiple spring constants, with different winding methods midway through.

(2) The spring person shown in this embodiment is omitted as necessary.

It is not even possible that this is possible.

Effects of the Invention According to the screw tightening device of the present invention, as is clear from the above explanation, it is possible to move the pit at high speed near the position 1 where screw tightening is started, and when the screw tightening is started, the workpiece It is equipped with a mechanism that absorbs and alleviates the impact of impact at the tip of the screw, stabilizes the bite of the screw, and is equipped with a spring that generates an appropriate pressure force when the screw is tightened (1). It is possible to perform automatic, efficient, and reliable high-speed screw tightening for several screws.

In addition, according to this device, the moving motor can be controlled so that the pressing force does not become excessive during screwing, and as a result, the tightening torque is not affected by inappropriate pressing force, and the tightening torque is stabilized. The effect is that it is possible to achieve the following.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention, and FIG. 1 is a schematic configuration diagram of a driving section of a moving block, which is the main part of the present invention,
Figure 2 is a perspective view showing the overall configuration, Figure 3 (IL),
(b) and (C) are explanatory diagrams of the lowering movement of the screw tightening head during the screw tightening process. FIG. 4 is a perspective view of a conventional screw tightening robot. 10...Moving block B, 11...Moving motor, 13...Moving block B, 14 (&
)... Spring 8516(b)...
Spring 8516... Screw tightening bit, 17
...Main controller, 18...Screw tightening controller.

Claims (3)

[Claims] (1) Movement that constitutes a screw tightening bit, a screw tightening head equipped with a tightening motor that rotationally drives the screw tightening bit, and a linear sliding bearing that allows the screw tightening head to move in the distance direction relative to the workpiece. a block A, a moving block B constituting the linear sliding bearing that transmits power from the moving motor to the moving block A via a spring, and a control means for controlling drive of the moving motor in response to a screw tightening process. , two types of springs with different spring constants are attached, and one spring A with a small spring constant connects moving blocks A and B, and the other spring B with a large spring constant connects moving blocks A and B.
A screw tightening device characterized in that the screw tightening device is installed so that a tensile force is generated when and B are separated by a predetermined distance or more. (2) The screw tightening device according to claim 1, wherein a deformable spring having a plurality of spring constants is attached as the spring. (3) The screw tightening device according to claim 1, wherein the spring is a spring attached so as to generate a tensile force when separated by a predetermined distance or more.