JPH05185322A - Wire electric discharge machining device - Google Patents

Abstract

PURPOSE:To embody long-time unmanned continuous machining by providing with a replacing means by which a plurality of wire-bobbin retaining devices can be selectively replaced, and a carrying means for carrying a wire electrode for automatically setting it after replacement. CONSTITUTION:When a wire-electrode remaining amount detecting means 46 detects that the wire-electrode 1a wound around a wire bobbin 2a has reached a predetermined remaining amount, a wire-bobbin retaining device 40a is withdrawn from a wire electric discharge machining device by a replacing means 42, and another wire-bobbin retaining device 40a is moved and installed. Then, the end of a wire electrode 1b that has been retained by the retaining means 60b of this wire-bobbin retaining device 40a is drawn out, and the wire electrode 1b is carried by a wire-electrode carrying means 50 up to a wire-electrode automatic feeding device 7, and electric discharge machining is restarted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire electric discharge machining apparatus for machining a work piece into a desired shape by means of electric discharge energy supplied between a wire electrode and the work piece, and particularly, for a long time continuous operation. The present invention relates to a wire electric discharge machine that enables machining.

[0002]

2. Description of the Related Art FIG. 7 is a schematic view showing a conventional wire electric discharge machine, in which 1 is a wire electrode, 2 is a wire bobbin, and the wire electrode 1 is unwound from a wire bobbin 2. Reference numeral 3 is a shaft to which the wire bobbin 2 is attached, and 4 is a braking means directly connected to the shaft 3, which generates a tension when the wire electrode 1 is unwound. Reference numeral 5 is an idler, 6 is a brake mechanism, and the idler 5 and the brake mechanism 6 constitute a wire electrode traveling system. 7 is an automatic wire electrode feeder, 8 is a pinch roller capstan mechanism for feeding the wire electrode 1, 9 is an upper wire electrode guide, and 10 is an upper wire electrode guide 9 which slidably supports the wire electrode 1. The pipe guide 11 at the tip is the work piece, and is installed on the cross table of the machine body (not shown).
Shape processing is performed by arbitrarily moving relative to the wire electrode 1. Reference numeral 12 is a lower guide, and 13 is a lower wire electrode which is built in the lower guide 12 so as to slidably support the wire electrode 1 and which is arranged below the workpiece 11 at a position facing the pipe guide 10. Be a guide. Reference numeral 15 is a power supply for supplying power to the wire electrode 1 while sliding on the wire electrode 1, and 16 is the wire electrode 1 and the workpiece 1.
It is a power source that supplies machining power for generating discharge energy during one period. 20 is a wire electrode collecting mechanism, and 21
Is a motor, 22 is a drive belt connected to the motor 21,
A driven belt 24 is in contact with the drive belt 22 and is configured to collect the wire electrode 1 sent out. In addition, 29 has shown the wire electrode collection box.

FIG. 8 shows a specific example of a wire bobbin holding device, and 40 is a wire bobbin holding device, and the same parts as those in FIG.

The conventional device is constructed as described above,
Next, the wire electrode supply operation will be described. The wire bobbin 2 is attached to the shaft 3 by manual operation. The wire electrode 1 unwound from the wire bobbin 2 is stretched on a wire electrode traveling system composed of an idler 5 and a brake mechanism 6, and the tip is set in the wire electrode automatic feeder 7. The set wire electrode 1 is fed by the driving of the pinch roller capstan mechanism 8, and the pipe guide 10
Is sent to the upper wire electrode guide 9 and passes therethrough. Further, the wire electrode 1 is continuously fed and is supplied to the workpiece 11 and the lower guide 12. Further, the wire electrode 1 that has passed through the lower wire electrode guide 13 is
5, then, held between the drive belt 22 and the driven belt 24 of the wire electrode recovery mechanism 20, and outside the main body of the wire electric discharge machine according to the movement of the drive belt 22 driven by the drive motor 21. Sent to. The delivered wire electrode 1 is recovered in the wire electrode recovery box 29, and a series of wire electrode supply operations is completed.

Next, the operation of performing the wire electric discharge machining will be described. The wire electrode 1 is usually a wire electrode recovery mechanism 2
With 0 motion, the vehicle is traveling at a speed of about 5 to 10 m / min. In the case of machining, a voltage is applied between the wire electrode 1 and the workpiece 11 to cause the workpiece 11 and the wire electrode 1 to move relative to each other while generating an electric discharge.
Realizes the desired shape processing.

[0006]

Since the conventional wire electric discharge machining apparatus is constructed as described above, when the machining distance becomes long due to a large and complicated machining which requires long time wire electric discharge machining, In the case of performing repetitive machining that requires finishing accuracy, the wire electrode wound around the wire bobbin disappears during machining, and there is a problem that wire electric discharge machining cannot be performed.

There is also a case where a large wire bobbin is used so as to enable continuous machining for a long time, but in this case, the winding diameter of the wire bobbin becomes large and the tension change of the wire electrode at the outer circumference and the inner circumference becomes large. Therefore, there is a problem that stable control of the tension of the wire electrode becomes complicated and expensive. In addition, since the wire electrode is finite in any case and further increases in weight, not only the replaceability of the wire bobbin deteriorates but also there is a drawback that it is a work for carrying heavy objects and is dangerous.

The present invention has been made to solve the above problems, and when the wire electrode set in the wire electric discharge machine disappears, the wire bobbin is automatically replaced and the wire electrode is automatically set. By doing so, the purpose is to realize long-time continuous processing unattended.

[0009]

A wire electric discharge machine according to a first aspect of the present invention includes a plurality of wire bobbins that rotatably support a wire bobbin around which a wire electrode is wound and that have a holding means for holding the tip of the wire electrode. A holding device, a wire electrode remaining amount detecting means for detecting that the wire electrode wound on the wire bobbin has reached a preset remaining amount, and the wire bobbin holding device when the wire electrode remaining amount detecting means operates. Is removed from the wire electric discharge machine and another wire bobbin holding device is moved and installed to replace the wire bobbin holding device and the tip of the wire electrode held by the holding means of the wire bobbin holding device is pulled out to automatically supply the wire electrode. The wire electrode transport means is configured to transport the wire electrode to the apparatus.

The wire electric discharge machine according to the second invention is
The wire electrode feeding means is incorporated into the wire electrode holding means in the wire bobbin holding device of the first invention.

A wire electric discharge machine according to a third aspect of the present invention rotatably supports a wire bobbin around which a wire electrode is wound, and a plurality of wire bobbin holding devices having holding means for holding the tip of the wire electrode. When the wire electrode remaining amount detecting means for detecting that the wire electrode wound on the wire bobbin reaches a preset remaining amount and the wire electrode remaining amount detecting means are operated, the wire bobbin holding device is operated for the wire discharge. The wire bobbin holding device replacing means for moving the wire bobbin holding device away from the processing device and moving the other wire bobbin holding device, and the wire electrode feeding means incorporated in the wire bobbin holding device are provided.

A wire electric discharge machine according to a fourth invention is
The wire bobbin holding means of the wire bobbin holding device of the first invention comprises a shaft for rotatably supporting the wire bobbin and braking means connected to the shaft for braking the wire bobbin, and the braking means is electrically driven. Is used, and the wiring to the electric braking means is composed of a detachable connection mechanism.

[0013]

In the wire bobbin holding device exchanging means according to the first aspect of the invention, the empty wire bobbin holding device which has finished winding the wire electrode is withdrawn from the wire electrode supplying portion of the wire electric discharge machining, and a new wire bobbin holding device is moved and installed.

Further, the wire electrode tip end holding means in the second invention holds the wire electrode unwinding tip end portion from the wire bobbin, and when the wire bobbin holding device is moved and installed by the exchanging means, the wire electrode is held. Stabilize the feeding of the wire electrode to the conveying means.

Further, in the wire bobbin holding device according to the third aspect of the present invention, when the wire electrode has a large diameter, the feeding means is omitted and the wire electrode is directly fed to the wire electrode automatic feeding device only by the wire electrode feeding means.

Further, the detachable connection mechanism according to the fourth aspect of the invention does not require wiring processing between the wire electric discharge machine and the wire bobbin holding device.

[0017]

【Example】

Example 1. Hereinafter, an embodiment of the first invention will be described with reference to FIGS.
Will be described. In the figure, the same parts as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted. Further, the auxiliary symbols a and b are respectively the first wire bobbin holding device and the second wire bobbin holding device.
2 shows the wire bobbin holding device of FIG. 1 in FIG.
0a, 40b are wire bobbin holding devices, 42a, 42b
Is a replacement means for selectively replacing the wire bobbin holding devices 40a and 40b, and an actuator such as an air cylinder can be used. Reference numeral 44 denotes a guide rail fixed to the machine body, and the wire bobbin holding devices 40a, 40
It is slidably engaged with b. Reference numeral 46 denotes a wire electrode remaining amount detecting means. In this embodiment, a photoelectric switch is used, and a light emitter and a light receiver are arranged with the wire bobbin 2a interposed therebetween. When the remaining amount of the wire electrode 1 of the wire bobbin 2a becomes small, light reaches the light receiving side and sends a signal to a control device (not shown) to detect the remaining amount.

Numeral 50 is a carrying means for carrying the wire electrode 1. In this embodiment, a suction aspirator is used. A transport pipe 52 connects between the idler 5 and the brake mechanism 6 that form the wire electrode transport system. Reference numerals 60a and 60b are holding means for holding the wire electrodes 1a and 1b.

FIG. 2 is a sectional view showing details of the wire bobbin holding device 40a. 57 is a housing base, 58 is a bearing, and 60a is a holding means for holding the wire electrode 1a. The compression spring 62, the holding plate 63, and the compression spring. It is composed of a holding plate 63 that is pressed by 62 and a shaft 64 that holds and holds the tip end portion of the wire electrode 1.

Next, the first embodiment will be described with reference to the flow chart showing the outline of the replacing operation of the wire bobbin holding device 40 of FIG.
The operation of the device shown in FIG. While the workpiece 11 is being processed by the wire electric discharge machine, the wire electrode remaining amount detecting means 46 detects that the wire electrode 1 has become less than the preset remaining amount (step 10).
1), the processing is temporarily stopped (step 102), the wire electrode 1a remaining on the wire bobbin 2a is rapidly collected by the wire electrode collecting mechanism 20, and the wire bobbin 2a is emptied (step 103). Next, the exchanging means 42a is driven to move the empty wire bobbin holding device 40a on the wire bobbin side downward from the wire electrode supply portion of the wire electric discharge machine to withdraw (step 104). Next, the wire bobbin holding device 40b to which the new wire bobbin 2b is attached is moved downward and set in the wire electrode supply portion of the wire electric discharge machine by the exchanging means 42b (step 105). At this time, the tip of the wire electrode 1b unwound from the wire bobbin 2b is held by the holding means 60b, and is accurately positioned at a position facing the carrying means 50 on the main body side.

Next, the conveying means 50 constituted by supplying a fluid to an aspirator, for example, is driven to suck the tip of the wire electrode 1 and fed into the conveying pipe 52, which is guided and guided by each idler 5 and the like. The wire electrode 1 is supplied to the automatic wire electrode supply device 7 while being stretched over the brake mechanism 6 (step 107). The wire electrode 1 set in the wire electrode automatic supply device 7 passes through the upper wire electrode guide 9 by the wire electrode automatic supply device 7, penetrates the workpiece 11 and recovers the wire electrode through the lower wire electrode guide 13. The mechanism 20 is reached (step 107), and the wire electrode 1 is stretched by the operation of the wire electrode recovery mechanism 20 (step 108). When the setting is completed in this way, machining is automatically restarted.

Example 2. Next, an embodiment of the second invention will be described with reference to FIG. In the figure, the same parts as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted. FIG. 3 is a perspective view showing the wire bobbin holding device 40, and 70 is a feeding means for the wire electrode 1, which is constituted by, for example, a pinch roller capstan mechanism. 72 is a motor, 7
Reference numeral 4 denotes a capstan roller, and 76 denotes a one-way clutch, which engages with the capstan roller 74 and can rotate in the feeding direction of the wire electrode 1, but does not rotate in the opposite direction, so that the wire electrode 1 is not rotated. It is configured to hold. Reference numeral 78 is a pinch roller, 80 is a lever, and 82 is a spring, and the pinch roller 78 is pressed against the capstan roller 74 via the lever 80.

Next, the operation of the apparatus shown in the second embodiment will be described. After the wire bobbin holding device 40 is replaced, the tip of the wire electrode 1 is held by a capstan roller 74 incorporating a one-way clutch 76 driven by a motor 72 and a pinch roller 78 rotatably supported by a lever 80. In addition to constituting the holding means, the motor 72 drives the capstan roller 74 to serve as the wire electrode feeding means 70 for feeding the wire electrode 1. After exchanging the wire bobbin holding device 40, the wire electrode feeding means 70 is operated, and at the same time, the conveying means 50 is also driven to surely feed the conveying means 50 and assist the conveying force.

Example 3. In addition, as an embodiment of the third invention, by omitting the carrying means 50 and operating the motor 72 of the wire electrode feeding means 70 incorporated together with the function of the holding means 60 in the wire bobbin holding device 40, There is also one in which the stun roller 74 is driven to convey the wire electrode 1 to the wire electrode automatic supply device 8 via the conveyance pipe 52.

Example 4. An embodiment of the fourth invention will be described with reference to FIG. In FIG. 4, the same parts as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted. FIG. 4 is a plan view of an apparatus according to an embodiment of the fourth invention, and FIG. 5 is a detailed sectional view of an electrically sliding portion thereof. 85 is a brush, 8
7 is a spring, 89 is a case, 90 is a connector, and 92 is a lead wire. The brush 85 is pressed against the case 89 by the spring 87, and is configured to surely slide with the connector 90 installed in the machine body in a use state. Further, the lead wire 92 connects between the motor 4 and the brush 85.

Next, the operation of the apparatus shown in the fourth embodiment of the invention will be described. The brush 85 and the contact 90 are positioned and brought into contact with each other at positions which automatically oppose each other when the wire bobbin holding device 40 is replaced, and the current supplied from the control device (not shown) is applied to the contact 90, the brush 85, and The motor 4 is energized via the lead wire 92.

In the above description of each embodiment, the two wire bobbin holding devices are automatically replaced.
It is also possible to replace more than one wire bobbin holding device.

Although the air cylinders are used as the exchange means 42a and 42b, other actuators such as a rack and pinion mechanism or an articulated robot may be used.

Further, although an example in which an aspirator is used as the transporting means 50 has been shown, other transporting means such as a belt drive will also produce the same effect.

[0030]

As described above, according to the present invention, a plurality of wire bobbin holding devices each including a holding means for rotatably supporting the wire bobbin and a holding means for holding the tip of the wire electrode are prepared. Exchange means for selectively exchanging a plurality of the wire bobbin holding devices, conveying means for conveying the wire electrodes for automatic setting after the exchange, and wire electrode automatic supply device for inserting the wire electrodes through the workpiece. Since the wire electrode set in the wire electric discharge machine runs out during machining, the wire bobbin holding device is automatically moved to the wire electrode supply part of the wire electric discharge machine to automatically install the wire electrode. It can be set, and long-time continuous processing can be realized unattended.

Further, the wire bobbin holding device has a holding means for rotatably supporting the wire bobbin and a wire electrode feeding means for holding the tip of the wire electrode, whereby the wire bobbin holding device is automatically replaced. This has the effect of further increasing the reliability when setting the wire electrode.

When the wire electrode is thick, the wire electrode can be set only by the wire electrode feeding means incorporated in the wire bobbin holding device, and the device can be inexpensively constructed.

Further, in the wire bobbin holding device using the electric braking means as the braking means for applying the brake to the wire bobbin, since the wiring to the braking means is composed of the detachable connecting mechanism, the wiring processing is remarkably performed. Since it becomes easier and the structure of the device is simplified, it is possible to obtain a cheap and highly reliable wire electric discharge machine.

[Brief description of drawings]

FIG. 1 is a schematic view showing a wire electric discharge machine according to an embodiment of the first invention.

FIG. 2 is a sectional view showing a wire bobbin holding means of a wire electric discharge machine according to an embodiment of the first invention.

FIG. 3 is a perspective view showing a wire bobbin holding means of a wire electric discharge machine according to an embodiment of the second and third inventions.

FIG. 4 is a view showing a wire bobbin holding means of a wire electric discharge machine according to an embodiment of the fourth invention.

FIG. 5 is a sectional view showing details of a detachable connection mechanism according to an embodiment of the fourth invention.

FIG. 6 is a flowchart showing a procedure for automatically replacing the wire bobbin holding device.

FIG. 7 is a schematic view showing a conventional wire electric discharge machine.

FIG. 8 is a sectional view showing a wire bobbin holding means of a conventional wire electric discharge machine.

[Explanation of symbols]

 1, 1a, 1b Wire electrode 2, 2a, 2b Wire bobbin 11 Workpiece 40, 40a, 40b Wire bobbin holding device 42, 42a, 42b Exchange means 46 Wire electrode remaining amount detecting means 50 Conveying means

Claims (4)

[Claims] 1. A wire electric discharge machining apparatus for machining a workpiece by generating an electric discharge in a minute gap between the wire electrode and the workpiece. The wire bobbin wound with the wire electrode is rotatably supported, and the wire electrode is also rotatably supported. A plurality of wire bobbin holding devices having a holding means for holding the tip of the wire bobbin, and a wire electrode remaining amount detecting means for detecting that the wire electrode wound on the wire bobbin has reached a preset remaining amount,
When the wire electrode remaining amount detecting means operates, the wire bobbin holding device is withdrawn from the wire electric discharge machine, and another wire bobbin holding device is moved and installed, and a wire bobbin holding device replacement means and a holding means of the wire bobbin holding device. And a wire electrode transporting means for transporting the wire electrode to an automatic wire electrode supply device by pulling out a tip portion of the wire electrode held by the wire electric discharge machine. 2. The wire electric discharge machine according to claim 1, wherein a holding means for holding a tip portion of the wire electrode of the wire bobbin holding device incorporates a wire electrode feeding means. 3. A wire electric discharge machining apparatus for machining a workpiece by generating an electric discharge in a minute gap between the wire electrode and the workpiece, while supporting a wire bobbin wound with the wire electrode rotatably and at the same time. A plurality of wire bobbin holding devices having a holding means for holding the tip of the wire bobbin, and a wire electrode remaining amount detecting means for detecting that the wire electrode wound on the wire bobbin has reached a preset remaining amount,
When the wire electrode remaining amount detecting means operates, the wire bobbin holding device is withdrawn from the wire electric discharge machining device, and another wire bobbin holding device is moved and installed to replace the wire bobbin holding device, and the wire bobbin holding device is incorporated into the wire bobbin holding device. And a wire electrode feeding means. 4. A shaft for rotatably supporting the wire bobbin holding means of the wire bobbin holding device, an electric braking device connected to the shaft for braking the wire bobbin, and a wire for connecting to the electric braking device is detachable. The wire electric discharge machine according to claim 1, 2 or 3, wherein the wire electric discharge machine comprises: