JP2732292B2 - Device for detecting remaining amount of wire electrode - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wire electric discharge machine for electric discharge machining of a workpiece by electric discharge energy generated between a workpiece and a wire electrode. It relates to a detection device.

[Conventional technology]

Generally, at present, in a wire electric discharge machine, a workpiece is machined by using a portion in which a wire electrode runs in a vertical direction, that is, a vertical direction. The wire electrode is guided by various rollers such as a potentiometer roller and a brake roller in an automatic wire supply device, and is supplied with an appropriate tension to a wire head having a wire guide.

On the other hand, the work table on which the workpiece is
It moves in the X direction and the Y direction according to the processing state of the workpiece according to a command from the device, and the movements of the two are combined, and the processing proceeds with the wire electrode supplied to the wire head. The work table is repeatedly subjected to servo movement, and the workpiece is subjected to electric discharge machining into a predetermined machining shape by the relative movement of the two.

Conventionally, in an automatic wire feeding device of a wire electric discharge machine, the remaining amount of the wire electrode wound on the source bobbin is detected by an operator by visually checking or measuring the amount of the remaining wire electrode, or by detecting a new wire electrode wound around the wire. The source bobbin is loaded into the source bobbin mounting means, the use time of the source bobbin is measured, the extended wire electrode is estimated, and the extended wire electrode is subtracted from the predetermined wire electrode length wound around the source bobbin. The remaining amount of the wire electrode was estimated.

[Problems to be solved by the invention]

However, it is difficult to accurately estimate the remaining amount of the wire electrode remaining on the source bobbin in the automatic wire feeding device of the wire electric discharge machine, as in the past, and therefore, it is difficult to always perform the operation. Must continue monitoring to observe the consumption of the wire electrode.
Or, if the monitoring is neglected, the wire electrode is lost during the electric discharge machining, and the machining is interrupted and left for a long time, so that the machining time is wasted and the machining efficiency is reduced.

In addition, despite the incorporation of the automatic wire feeder, the wire electrode is unwound from the source bobbin and is lost, so that there is a problem that it is difficult to automate the electric discharge machining of the wire electric discharge machine.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problem, and detects the winding diameter of a wire bobbin of a wire electrode in a source bobbin of a wire electric discharge machine incorporating an automatic wire feeding device and winds the wire around the source bobbin. The wire diameter of the wire electrode measured in advance, the winding amount of the wire electrode,
The remaining amount of the wire electrode is calculated from the wire electrode length, the effective machining time of the wire electric discharge machining can be displayed, and the structure itself is simple and can be easily incorporated into an existing source bobbin, thereby reducing costs. An object of the present invention is to provide a device for detecting the remaining amount of a wire electrode.

[Means for solving the problem]

The present invention is configured as follows to achieve the above object. That is, the present invention provides a wire electric discharge machine for electric discharge machining of a workpiece by electric discharge energy generated between a workpiece and a wire electrode sent out from a source bobbin. A wire winding diameter of the wire electrode wound on the source bobbin, which includes a rotatable roller arm having a roller attached to one end in contact with the contact state and a potentiometer for outputting an electric signal corresponding to a rotation angle of the roller arm. An electric signal corresponding to the length of the wire electrode in response to the electric signal from the potentiometer based on a previously calculated length of the wire electrode corresponding to the rotation angle of the roller arm. Calculating means for calculating and outputting the length of the wire electrode calculated by the calculating means. Display for displaying the remaining amount of the wire electrode, which is determined in response to the electrical signal response, it relates to residual amount detection device of the wire electrode, characterized in that it consists of.

[Action]

The device for detecting the remaining amount of a wire electrode according to the present invention is configured as described above, and operates as follows. That is, the device for detecting the remaining amount of the wire electrode comprises a sensor for detecting the wire winding diameter of the source bobbin wound up by the wire electrode. To detect the amount as the output signal of the potentiometer,
In response to the detection signal of the sensor, the length of the wire electrode calculated in advance corresponding to the detection signal is calculated by a calculation means, and an electric signal corresponding to the length of the wire electrode is output. Since the remaining amount of the wire electrode corresponding to the electric signal is displayed on the display, the configuration of the sensor itself is simple and the winding diameter can be detected accurately.
It is possible to confirm the effective machining time during which the wire electric discharge machining can be performed by the display of the display, and therefore, it is possible to prevent a loss of machining time due to a broken wire electrode or the like during machining.

〔Example〕

Hereinafter, an embodiment of a wire electrode remaining amount detecting device according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory view showing one embodiment of a device for detecting the remaining amount of a wire electrode according to the present invention.

In a wire electric discharge machine incorporating an automatic wire feeder, a wire electrode 2 travels with a predetermined tension applied in a wire electrode traveling system, and generates a discharge between a workpiece and the wire electrode 2 at an electric discharge machining portion. The workpiece is subjected to electrical discharge machining by the discharge energy.

In a wire electric discharge machine, a workpiece to be subjected to electric discharge machining is fixedly mounted on a work table by an appropriate clamping means. An upper wire head and a lower wire head are mounted on the Z-axis head constituting the automatic wire supply device. Inside these heads, a power supply for supplying a current to the wire electrode 2 and a guide for the wire electrode 2 A wire guide, a jet nozzle for spraying a machining liquid to a workpiece, and the like are incorporated.

In a wire electric discharge machine, a workpiece is set on a work table, and the work table is generally configured to be movable in a horizontal direction, that is, in an X direction and a Y direction. That is, the work table on which the workpiece is mounted moves in the X and Y directions according to the processing status of the workpiece according to a command from the NC device, and the wire electrode 2 supplied to the upper wire head is moved.
The processing is configured to proceed between the steps. Furthermore,
The wire electric discharge machine has an upper nozzle and a lower nozzle which are machining liquid jet nozzles attached to upper and lower wire heads.

The wire electric discharge machine is provided with an automatic wire supplying device for supplying the wire electrode 2 to the electric discharge machining site, and constitutes a wire traveling system of the wire electrode 2. The wire running system of the automatic wire feeder mainly includes a source bobbin 1 for accommodating the wire electrode 2 and feeding out the wire electrode 2, guiding the wire electrode 2 to an electric discharge machining site to apply a predetermined tension to the wire electrode 2. Various rollers provided for applying and pulling out and discharging the wire electrode 2 are incorporated.

In general, the source bobbin 1 can be loaded with a variety of wound wire electrodes 2 successively and loaded into a source bobbin mounting device. When the source bobbin 1 is loaded into a wire electric discharge machine, a work piece is generally used. Source bobbin 1 on which the optimal wire electrode 2 is wound according to the processing shape of
Is selected and incorporated into the automatic wire feeder.
When the workpiece is changed to another workpiece, the optimum wire electrode 2 for the changed workpiece is selected and replaced with the source bobbin 1 in which the wire electrode 2 is wound up.

The source bobbin 1 is rotatably supported for feeding out the wire electrode 2, and is configured to apply a slight braking force to the wire electrode 2. The wire electrode 2 sent from the source bobbin 1
The feeding of the wire electrode 2 is smoothly performed by a roller or the like disposed in the wire electrode traveling system. The wire traveling system is provided with a plurality of direction change rollers for changing the direction of the wire electrode 2. A brake device including a tension roller and a brake roller is arranged between these direction change rollers.

In the wire traveling system of the wire electrode 2, a pinch roller and a holding roller that can be pulled out at a constant speed across the wire electrode 2 are provided downstream of the lower wire head in order to pull out the wire electrode 2 from the wire electric discharge machining site. It is arranged.

FIG. 1 shows an embodiment of a wire electrode remaining amount detecting device according to the present invention.

In this device for detecting the remaining amount of wire electrode, the wire electrode 2 is sent out from a source bobbin 1 which rotates about a rotating shaft 16 with the progress of electric discharge machining. Although it changes gradually, it has a sensor for detecting the winding diameter.

A roller is in contact with the outermost peripheral surface of the wire electrode 2 wound up on the source bobbin 1. The roller 4 is rotatably attached to one end of a roller arm 5.
It is preferable that the roller 4 is located at a payout point of the wire electrode 2 fed from the source bobbin 1 in order to detect an accurate winding diameter.

Although not shown, the roller 4 may be configured to be slidable in the width direction of the source bobbin 1 in accordance with the feeding of the wire electrode 2. For example, this can be achieved by forming the end of the roller arm into a forked shape and arranging the roller 4 to be rotatable and slidable on a shaft attached between the forked portions.

The other end of the roller arm 5 is fixed to a rotating shaft 17,
An arm 11 is fixed to the other end of 17. A spring 7 is attached to the arm 11, and the roller 4 is pressed in contact with the wire electrode 2 wound on the source bobbin 1 by the action of the spring 7.

The gear 6 is fixed to the rotating shaft 17. The gear 6 meshes with a gear 9 fixed to an input shaft 18 of the potentiometer 8. The rotation signal input to the potentiometer 8 is input to the controller 10. With such a configuration, as shown by the chain line in FIG.
When the wire diameter is reduced due to the feeding of the wire electrode 2 from
The roller arm 5 rotates by the angle θ in accordance with the decrease in the winding diameter of the wire electrode 2. This rotation amount becomes the rotation of the gear 6 and is transmitted to the gear 9 at an increased or reduced speed for proper rotation.

Next, the rotation amount of the gear 9 is transmitted to the input shaft 18 and input to the potentiometer 8. The potentiometer 8 can detect the winding diameter of the wire electrode 2 around the source bobbin 1 based on the input signal of the rotation amount. Furthermore,
The potentiometer 8 outputs the winding diameter of the wire electrode 2 to the controller 10 as an electric signal. The electric signal input from the potentiometer 8 to the controller 10 is
The electric signal amplified by the amplifier is amplified and input to the comparator 12.

By the way, in response to the electric signal corresponding to the winding diameter of the wire electrode 2 wound on the source bobbin 1, information such as the diameter of the shaft for winding the wire electrode 2 of the source bobbin 1, the winding width, and the like are obtained. Wire electrode 2
Information such as the wire diameter, winding diameter length, winding width, and initial wire length is measured in advance and known. Therefore, various information on these is input to the parameter setting device 14 of the controller 10.

In the comparator 12, the electric signal input from the potentiometer 8 is input to the arithmetic unit 13, and the length of the wire electrode 2 is calculated according to the electric signal of the wire electrode winding diameter. Since the length of the electrode 2 is input as information, the remaining amount of the wire electrode 2 can be immediately and accurately detected. Thereby,
The remaining amount of the wire electrode 2 according to the detection signal can be displayed on the display 3.

If the remaining amount of the wire electrode 2 is known, the operator can predict the effective processing time for the wire electrode 2 thereafter. The display 3 may be configured to display the effective processing time. Further, in addition to the indicator 3, when the wire electrode 2 is reduced to a predetermined remaining amount or less, an alarm means can be used together in response to a detection signal of the sensor.
The operator can immediately and surely confirm the remaining amount of the wire electrode 2 by the alarm means, and can perform an operation of replacing the source bobbin 1 on which the wire electrode 2 is wound.

Accordingly, it is possible to shorten the interruption time due to the absence of the wire electrode 2 in the electric discharge machining of the workpiece, and to shorten the loss time as much as possible to improve the machining efficiency. In addition, an auxiliary source bobbin is prepared, and when the effective processing length of the wire electrode of the main source bobbin is consumed, the main source bobbin is automatically changed to the auxiliary source bobbin according to the effective processing length consumption detection signal. You can also.

〔The invention's effect〕

The device for detecting the remaining amount of a wire electrode according to the present invention is configured as described above, and has the following effects. That is, the device for detecting the remaining amount of the wire electrode includes a sensor for detecting a wire winding diameter of the source bobbin that winds up the wire electrode, and a pre-calculated corresponding to the detection signal in response to the detection signal of the sensor. A source for winding the wire electrode because it is composed of arithmetic means for outputting an electric signal corresponding to the length of the wire electrode and a display for displaying the remaining amount of the wire electrode corresponding to the electric signal of the arithmetic means; The remaining amount of the wire electrode wound on the source bobbin is immediately detected in accordance with the amount of decrease in the bobbin winding diameter,
According to the display on the display, the effective machining time in which the wire electric discharge machining can be performed can be accurately and immediately estimated or confirmed.

If this device for detecting the remaining amount of the wire electrode is used, it is possible to improve the processing efficiency by minimizing the occurrence of a loss in the processing time due to the breakage of the wire electrode during the processing of the workpiece. The device for detecting the remaining amount of wire electrode is
With the above configuration, it is possible to easily use an alarm means in response to the detection signal when the wire electrode is reduced to a predetermined remaining amount or less. By this means, the remaining amount of the wire electrode can be immediately and reliably confirmed, and the processing efficiency can be more effectively improved.

In addition, when the auxiliary source bobbin is prepared, if the wire electrode processing amount becomes less than the effective amount, the detection signal can automatically change the feeding bobbin of the wire electrode. Can be achieved smoothly. Moreover, the structure itself is simple and the control is simple, and there is no failure and the cost can be reduced.

Further, since the sensor detects a rotation angle of a roller arm having one end provided with a roller abutting on the wire electrode wound on the source bobbin as an output signal of a potentiometer, the structure of the sensor itself is simple and accurate. The diameter can be detected, and the sensor can be easily incorporated into an existing source bobbin.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a device for detecting the remaining amount of a wire electrode according to the present invention. 1 ... source bobbin, 2 ... wire electrode, 3 ... display, 4 ...
... Roller, 5 ... Roller arm, 6,9 ... Gear, 8 ... Potentiometer, 10 ... Controller, 12 ... Comparator, 13 ...
Arithmetic unit, 14 ... Parameter setting device.

Claims (1)

(57) [Claims] 1. A wire electric discharge machine for electric discharge machining of a workpiece by electric discharge energy generated between a workpiece and a wire electrode sent from a source bobbin, the wire being wound on the source bobbin. The wire winding diameter of the wire electrode wound on the source bobbin, which is composed of a rotatable roller arm having a roller attached at one end and a potentiometer that outputs an electric signal corresponding to the rotation angle of the roller arm, is provided. Based on a sensor to be detected and a length of the wire electrode calculated in advance corresponding to a rotation angle of the roller arm,
Calculating means for calculating and outputting an electrical signal corresponding to the length of the wire electrode in response to the electrical signal from the potentiometer; and calculating the electrical signal corresponding to the length of the wire electrode calculated by the calculating means. A display for displaying the remaining amount of the wire electrode determined correspondingly, the remaining amount detecting device for the wire electrode.