JPS632626A - Wire electric discharge machine - Google Patents

Abstract

PURPOSE:To aim at the maintenance of high accuracy for a long period of time and secure such a workpiece that is high in accuracy of finishing, by driving a drive system such as a table, a saddle or the like directly with a linear motor, making a drive system unit into compact in size, and eliminating friction in a power transmission system. CONSTITUTION:A moving part 30a of a liner motor is clamped to a table 20, and a fixed part 30b is clamped to a bed 22. And, this moving part 30a is constituted of a permanent magnet 40 and both electromagnets 42a and 42b. Here, a pulse current is made to pass through these electromagnets 42a and 42b whereby the moving part 30a is driven by dint of magnetic force to be produced in a gap with the fixed part 30b. At this time since travel corresponding to one pulse of a linear pulse motor is constant strictly it has both positional detection and positioning functions in combination. With the abovementioned constitution, driving froce of the linear motor 30 is directly transmitted to the table 20 and the bed 22 so that power transmission efficiency is high enough, thus such a workpiece that is high in accuracy of finishing is securable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement of a wire electrical discharge machining apparatus.

[Conventional technology]

Conventionally, tables, saddles, etc. have been driven by a drive system composed of a rotary motor, a power transmission gear, and a ball screw. In addition, for position detection and positioning,
Positioning was performed by detecting the rotation angle of the motor and estimating the linear movement distance of the ball screw from that angle.

Figure 3 shows an example of a conventional drive system (20)
is a table, (22) is a bed, (10) is a rotary motor, (12) is a motor rotation angle detection device, (14) is a power transmission gear, (16) is a ball screw, and the ball screw male thread (16a) is attached to the table (20) side, and the ball screw 16b) is attached to the bed (22) side.

Next, the operation will be explained. Rotational force is generated by the rotary motor (10), and then the power is transmitted to the ball screw male thread (16a) by the power transmission gear (14), and the rotation occurs between the ball screw male thread (16a) and the ball screw female thread (16b). Convert motion to linear motion. Therefore, the ball screw male screw (1f3) is attached to the table (20).
a) and the female ball screw (16
Due to the relative movement of b), the table (20) and bed (2)
2) Move 8! It is structured as follows.

Rotary morph (10) is used for magko, position detection, and positioning.
The rotation angle is detected by the Aromorph rotation angle detection device (12) attached to the
) and the ball screw 1 (ib) relative movement distance is H
1 and then positioning the table (20).

[Problem that the invention seeks to solve]

Conventional wire electrical discharge machining equipment as described above converts rotational motion into linear motion and utilizes it, resulting in gear backlash, ball screw efficiency, and ball screw problems due to changes in the position of the male and female ball screws in the power transmission system. There were problems such as changes in the rigidity of the gears and increased positioning errors due to friction between gears and ball screws.

The present invention was made to solve the above problems, and eliminates the conventional drive system using a rotary motor.
It is an object of the present invention to provide a wire electrical discharge machining device that uses a linear motor to move a table with high precision and efficiency, and also enables high precision machining.

[Means for solving problems]

A wire electrical discharge machining apparatus according to the present invention uses a linear motor to drive a movable portion including a table and a saddle.

[Effect]

In the present invention, since the drive system for the table, saddle, etc. is directly driven by a linear motor, highly accurate drive control of the table, saddle, etc. is possible.

[Embodiments of the invention]

FIG. 1 is a sectional view showing an embodiment of the present invention, and in the figure, (20) and (22) are the same parts as the same reference numerals in the conventional example shown in FIG. C30) It is a beam near motor, and the movable part (30a) is fixed to the table (20), and the fixed part (30b) is fixed to the bed (22-1).

Figure 2 shows the structure of a linear pulse motor that is the IN of the linear motor (30), where (40) is a permanent magnet and (42) is a permanent magnet.
) is an electromagnet, and (40) , (42a) , (
42b) is the movable part (30a). In the linear pulse smoke having the above configuration, (42a),
By passing a pulse current through (42b), the fixed part (30
b) Due to the magnetic force generated between the movable part (30al
This is how it is driven. At this time, the moving scene corresponding to one pulse of the linear pulse motor is strictly constant, and therefore, this linear motor can perform both position detection and positioning functions.

In the wire electrical discharge machining apparatus configured as above,
The driving force of the linear motor (30) is directly applied to the table (20).
) and the bed (22), the power transmission efficiency is high, and since there is no friction in the drive system and position detection system, it is possible to maintain high accuracy over a long period of time.

In addition, although the above embodiment shows an example in which a linear motor is provided in the table/saddle, the same effect as in the above embodiment can be obtained even if it is used in all other parts of the equipment M that perform linear movement. .

〔Effect of the invention〕

As described above, according to the present invention, the drive system is compact because the table is conventionally driven by a rotary motor, a power transmission gear, and a ball screw, but the drive position is detected and positioned by a linear motor. become,
In addition, since there is no friction in the power transmission system, high accuracy can be maintained for a long period of time, and there is an effect that a workpiece with high machining accuracy can be obtained.

[Brief Description of the Drawings] Fig. 1 is a configuration diagram showing one embodiment of the present invention, Fig. 2 is a configuration diagram showing another embodiment, and Fig. 3 is a configuration diagram showing a table drive system according to a conventional technique. It is a diagram. In the figure, 10: rotary motor, 12: morph rotation angle detection device, 16a: male ball screw, 16b - female ball screw, 20: table, 22: bed, 30a:
Linear motor movable part, 30b: linear motor fixed part,
40: permanent magnet, 42a: electromagnet, 42b: electromagnet, and the same reference numerals indicate the same or corresponding parts.

Claims (3)

[Claims] (1) In an apparatus for machining the conductive workpiece by discharging machining fluid into the machining part formed between the wire electrode and the conductive workpiece and generating electric discharge in the machining part, the table/saddle A wire electrical discharge machining device characterized in that a linear motor is installed as a drive source for a movable part including. (2) The wire electrical discharge machining apparatus according to claim 1, wherein the linear motor has both position detection and positioning functions. (3) The wire electrical discharge machining apparatus according to claim 2, wherein the linear motor is a linear pulse motor.