JPH0241822A - Wire electric discharge machining device - Google Patents

Abstract

PURPOSE:To eliminate the influence of bounce of a wire, and to enable the positioning of the end surface in the stationary state of the wire by arranging a wire constant-speed feeding mechanism in a position near to a wire supply bobbin, and a wire tension generating mechanism in a wire collecting part respectively. CONSTITUTION:A wire constant-speed feeding mechanism 11 consisting of a pulley 11a, an auxiliary pulley 11b, a motor 11c, or the like is arranged in the position directly after a wire supply bobbin 1, so that the influence of bounce of the wire so far frequently occurred can be eliminated to feed the wire stably. Further, a wire tension generating mechanism 12 consisting of a collection roller 12a, and a pinch roller 12b is arranged in a wire collection part, so that the positioning of the wire to the end surface of a workpiece in the stationary state of the wire can be achieved in a good reproducibility.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a wire electrical discharge machining device.

[Prior Art] FIG. 2 is a system diagram showing an example of a wire beam feeding system of a conventional wire electric discharge machining apparatus. In the figure, (1) is a wire supply bobbin, (2) is a wire that is drawn out from the wire supply bobbin (1), and (3) is connected to the shaft of the wire supply bobbin (1), and a light weight is attached to the wire (2). A brake motor for applying tension, (4) is a wire tension generation mechanism, an auxiliary pulley (4c) for applying tension to roller (4a), wire (2), and a powder brake attached to the shaft of roller (4a). It consists of (4b). (5) is an upper pulley, (6) is an upper wire guide, (7) is a workpiece, (8) is a lower wire guide, and (9) is a lower boob. (10) is a wire constant speed feeding mechanism, and the collection roller (
10a), a pinch roller (lOb) that rotates in contact with the collection roller (I Da), an AC motor (toe) connected to the shaft of the collection roller (10a), and an AC motor (10c).
) and a tacho generator (10d) attached to the shaft.

Next, this effect will be explained. The wire (2) unwound from the wire supply bobbin (1) is passed through the wire tension generation mechanism (4).
) so that the roller (4a) rotates without slipping on the wire (2), it is first wrapped around the roller (4a), then around the auxiliary pulley (4C), and then wrapped around the roller (4a) again.
), it is wound around the workpiece ( 7), passes through a lower guide (8) which is also provided at the lower part of the workpiece (7) and positions it for processing, and then passes through a lower pulley (9) to collect a collection roller (LOA).
) and pinch rollers (10b). The wire supply bobbin (+) is equipped with a brake motor (3), and when feeding the wire (2), the wire (2)
) is designed to generate a braking force of approximately 200 g to prevent the brake from disintegrating.

Further, the wire tension generating mechanism (4) generates a braking force in proportion to the current applied to the powder brake (4b) as the wire (2) runs, thereby generating tension in the wire (2).

On the other hand, the wire constant speed feeding mechanism (10) is driven by an AC motor (f
tachogenerator (10d) installed behind the
) detects the rotational speed of the collection roller (10a), and is controlled to a constant speed by a control device (not shown).

As described above, the wire (2), which runs at a constant speed while maintaining a predetermined tension, is connected to the workpiece (
Electrical energy is supplied between 7) and electrical discharge machining is performed.

[Problems to be Solved by the Invention] In the conventional wire electric discharge machining apparatus as described above, the wire (2) must be traveling even when positioning the end face. In this case, if there is slight eccentricity in the upper pulley (5), lower pulley 9), etc., the wire (2) will vibrate in the lateral direction, making it difficult to position the wire (2) with good reproducibility. In addition, there is a problem that the splashing of the wire (2) generated in the wire supply bobbin (1) also causes fluctuations in tension, deteriorating the machining accuracy.

The present invention was made in order to solve such problems, and an object of the present invention is to improve the accuracy of end face positioning and to obtain a wire electrical discharge machining apparatus that can realize a stable wire running system.

[Means for Solving the Problems] A wire electrical discharge machining apparatus according to the present invention has a wire constant speed feeding mechanism disposed close to a wire supply bobbin, and a wire tension generation mechanism disposed close to a wire collection section. It is.

[Function] In the present invention, the wire can be run stably by arranging the constant speed wire feeding mechanism close to the wire supply bobbin and arranging the wire tension generating mechanism near the wire collection section. .

[Embodiment] FIG. 1 is a system diagram showing the configuration of an embodiment of the main part of the present invention. Note that (1) to (9) indicate the same or equivalent parts as in the conventional example shown in FIG. In the figure, (11) is a wire constant speed feeding mechanism, (lla) is a pulley, (1lb) is an auxiliary pulley, (llc) is an AC motor, and (lid) is a tacho generator. (12) is a wire tension generation mechanism, (12a) is a collection roller, (12b) is a pinch roller, and (12c) is a DC motor.

Next, this effect will be explained. The wire (2) unwound from the wire supply bobbin (1) is fed to the constant speed wire feed mechanism (1).
1) In order to rotate the inner roller (lla) without slipping on the wire (2), it is first wrapped around the roller (lla), then around the auxiliary pulley (llb), and the roller (lla) is rotated once again. is sent to the upper pulley (5),
Pass through the upper wire guide (6) as in the conventional device,
The wire tension generating mechanism (12) passes through the workpiece (7), passes through the lower wire guide (8), and passes through the lower pulley (9).
) Collection roller (12a) and pinch roller (12b)
Run between the two. At this time, the wire feeding bobbin (
The operation of 1) is similar to that of the conventional device. The basic operation of the wire constant speed feeding mechanism (11) is the same as that of the conventional device, but
Since the DC motor (12c) is used as the actuator of the wire tension generator h'4 (12), a control device (not shown) performs constant current control on the DC motor (12c), thereby controlling the DC motor (12c). generates a constant torque and can apply a constant tension to the wire (2).

By doing this, in the conventional device, the wire (2)
The tension in the wire (2) that would not occur unless the wire (2) is running can be obtained in the wire (2) even in a stationary state without running, so the end face positioning performed before processing is performed with the wire (2) stationary. This makes it possible to perform highly accurate positioning.

Furthermore, since the wire constant speed feeding mechanism (11) performs speed feedback, damping can be improved in the portion where constant speed control is performed. Therefore, in the device according to the present invention, by arranging the wire constant speed feeding mechanism (11) immediately after the wire supply bobbin (1), the splash that occurs when unwinding the wire supply bobbin (1) in the conventional device is avoided. It is possible to eliminate the influence of

Furthermore, although the above embodiment shows the case where an AC motor is used for the wire constant speed feeding mechanism, the same effect can be obtained by using a DC motor.

[Effects of the Invention] As described above, according to the present invention, by arranging the wire constant speed feeding mechanism at a position close to the wire supply bobbin, stable wire feeding is achieved by eliminating the influence of wire bouncing. In addition, by disposing a wire tension generation mechanism in the wire collection section, it is now possible to position the wire with respect to the end face of the corrugated material while the wire is stationary, and the reproducibility of positioning can be improved. The synergistic effects described above can greatly improve machining accuracy.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the structure of an embodiment of the present invention, and FIG. 2 is a side view showing the structure of a conventional example. In the figure, (1) is a wire supply bobbin, (4) is a wire tension generation mechanism, (10) is a constant speed wire feed mechanism, and (1) is a wire tension generation mechanism.
1) is a constant speed wire feeding mechanism, (12) is a wire tension generating mechanism, and (12e) is a DC motor. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A wire electric discharge machining device is composed of a wire supply bobbin, a wire tension generation mechanism, and a wire constant speed feed mechanism. Wire electrical discharge machining equipment consisting of arranged mechanisms.