JPS6141691B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic feeding device for wire after wire breakage or cutting in a wire cut electric discharge machine using a wire electrode.

A wire cut electrical discharge machine has a pair of wire guide devices with a workpiece interposed therebetween, and a wire guided by these wire guide devices. Wire-cut electric discharge machining is a method of cutting and machining a workpiece by utilizing electrical discharge between the workpiece and the wire, but the wire may break due to an abnormal situation during machining.

Furthermore, when the same workpiece is subjected to multiple processes (for example, progressive type machining), it is necessary to cut the wire once in order to move the workpiece to a new processing position. Conventionally, it has been difficult to supply the wire again after the wire is broken due to such an abnormal situation or intentionally cut.

The present invention attempts to overcome the drawbacks of conventional wire electrical discharge machines and reliably automatically refeed the wire after the wire is disconnected or cut.

This will be explained below with reference to the drawings.

An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, 1 is a workpiece, and 2 is a start hole previously machined in the workpiece 1. In FIG. Reference numerals 3 and 4 designate a pair of wire guide devices with the workpiece 1 interposed therebetween, which are an upper wire guide device and a lower wire guide device, respectively. Reference numerals 5 and 6 denote guide operating mechanisms, which in this case are cylinders, for moving the upper wire guide device 3 to remove it from the guide position, making it easier for the wire to pass through, and returning it to its original position. 7 is a wire guided by an upper wire guide device 3 and a lower wire guide device 4, that is, a wire electrode, and is guided by an arrow 10 by a supply reel 8 and a take-up reel 9.
is being sent in the direction of. Reference numerals 11 and 12 are motors that drive the supply reel 8 and the take-up reel 9, respectively. 13 and 14 are rollers that clamp the wire electrode 7 by sandwiching it when the wire electrode 7 is broken or cut. Note that the rollers 13 and 14 are unnecessary unless the wire returns largely toward the supply reel 8 and is sucked into the wire guide device 4 when the wire electrode 7 is disconnected or cut. This roller 1
3 and 14 rotate only in the directions of arrows 16 and 17, respectively, and not in the directions of arrows 16' and 17'. 24 is provided between the workpiece 1 and the lower wire guide device 4, and after the wire electrode 7 is broken or at the time of cutting, the wire electrode 7 is clamped by the rollers 13 and 14 and removes unnecessary wire electrode 7. This is a cutter that performs cutting, and is attached to the cylinder 23 and moves in the front and rear directions. This cutter 2
Although it is possible to do this without 4, the following operations can be performed more reliably with the cutter. 18,
19 is a pulse motor for moving the start hole 2 in the workpiece 1 to a position where the wire electrode 7 passes when feeding the wire electrode 7 therethrough. Further, when processing the workpiece 1, this pulse motor moves the workpiece 1 to a predetermined position and changes the relative position between the workpiece 1 and the wire electrode 7. Reference numeral 20 is a pick-up member in the form of a thick wire, which is made of the same material as the wire electrode 7, for example, and is supplied from the supply reel 21. 22 is a motor that rotates the supply reel 21. The supply reel 21 and the motor 22 constitute an operation mechanism for the pick-up member. In this embodiment, the pick-up member 20 is a pick-up line, and hereinafter 20 will be explained using the pick-up line.

41 is a joining machine that joins both the wire electrode 7 and the pick-up line 20 at the point where the cutter 24 cuts the wire electrode 7 (for example, by soldering, gluing, spot welding), and the main function is to attach the wire to the pick-up line. It is a mounting means that can be used. This joining machine is attached to a cylinder 42 and moves back and forth. 25 is a joining machine that joins both the wire electrode 7 wound on the take-up reel 9 and the pick-up wire 20 above the upper wire guide device 3 after the wire electrode 7 is broken or cut; to move forward and backward. Reference numeral 27 denotes a cutter for cutting the pick-up wire 20 between the part where the wire electrode 7 and the pick-up wire 20 are joined by the splicing machine 25 and the supply reel 21 of the pick-up wire 20 after joining both the wire electrode 7 and the pick-up wire 20 using the splicing machines 41 and 25. It is attached to the cylinder 28 and moves in the front and rear direction.

Wire-cut electric discharge machining uses electric discharge between the workpiece 1 and the wire electrode 7 to cut the workpiece 1, but due to abnormal circumstances during machining,
The wire electrode 7 may be disconnected at an intermediate point between the upper wire guide device 3 and the lower wire guide device 4.

The operation after the wire electrode 7 is disconnected will be explained with reference to FIG.

First, the rollers 13 and 14 sandwich the wire electrode 7 and clamp it so that the wire electrode 7 does not fall out from the lower wire guide device 4. In this clamp, the rollers 13 and 14 are respectively indicated by arrows 1 and 14 during machining.
Although it is rotating in the directions of 6 and 17, the wire electrode 7
This is done by not rotating in the directions of arrows 16' and 17' after the rotation is stopped due to disconnection or cutting of the wire. When the cylinder 23 is driven in the clamped state, the cutter 24 comes forward and cuts the wire electrode 7. Next, the pulse motor 18,1
9 moves the start hole 2 in the workpiece 1 to the position where the wire electrode 7 passes, that is,
The workpiece 1 is moved precisely or approximately to a machining start position so that the line of attack 20 can easily pass through the workpiece 1. Furthermore, by driving the cylinders 5 and 6, the upper wire guide device 3 is placed in an open state so that the pick-up line 20 can easily pass through the wire guide device 3. In other words, the wire guide device 3 is moved and removed from the guide position so that the pick-up line 20 can easily pass through. In this state, the motor 22 is driven to rotate the supply reel 21 of the pick-up line 20 in the direction of the arrow 29,
0 passes through the open part of the upper wire guide device 3 and the starting hole 2 in the workpiece 1 until it is detected at the point where the wire electrode 7 is cut by the cutter 24, for example by a photoelectric switch. The pickup line 20 will be sent in the direction of the arrow 30. At this time,
In order to make the pick-up line 20 go straight, a guide for the pick-up line 20 is required near the supply reel 21, but this is omitted in the figure.

Next, by driving the cylinder 42, the joining machine 41 moves forward and joins the wire electrode 7 and the pick-up line 20. Further, by driving the cylinder 26, the joining machine 25 moves forward, and after the wire electrode 7 is broken or cut, the wire electrode 7' wound on the take-up reel 9 and the pick-up wire 20 are joined. Next, as the cylinder 28 is driven, the cutter 27 comes forward and cuts the pick-up line 20 between the supply reel 21 and the joining point of the wire electrode 7' and pick-up line 20 by the splicing machine 25. After this, the motors 11 and 12 are driven, and the supply reel 8
Then, the take-up reel 9 is rotated in the directions of arrows 8' and 9', respectively, so that the pick-up line 20 and the wire electrode 7 joined to the wire electrodes 7 and 7' are sent in the direction of the arrow 10.

After the re-supply of the wire electrode 7 is completed as described above, the upper wire guide device 3 is closed by driving the cylinders 5 and 6, and the pulse motor 1
8 and 19, the workpiece 1 is moved to the wire electrode 7
Return to the position at which the wire was disconnected. As a result, electrical discharge machining can be continued. Although the above description is about the operation when an unexpected wire breakage occurs, it can also be applied to cases where the same workpiece is subjected to a plurality of processes, such as in a progressive die.

In this case, the wire electrode 7 is cut by the cutter 24 installed between the workpiece 1 and the lower wire guide device 4, and the wire electrode 7 is re-supplied using the start hole at the next processing start position. It turns out. As described above, even in the case of an unexpected wire breakage, the wire electrode 7 is cut by the cutter 24, and this cutting allows the tips of the wires to be aligned and facilitates the subsequent wire feeding operation. These series of operations are executed under the control of a minicomputer or the like after detecting the disconnection of the wire electrode 7 using, for example, discharge current or rotation of the rollers 13 and 14.

In addition, when machining a workpiece from the outer circumferential edge of the workpiece, there is no start hole, but as in the case described above, when the wire breaks at the machining start position, that is, at a position where the progress of the pick-up member is not prevented by the workpiece, All you have to do is perform the wire resupply operation.

In the above embodiment, the disconnection position of the wire electrode 7 is determined between the upper wire guide device 3 and the lower wire guide device 4.
However, even if the wire breaks below the lower wire guide device 4, the above can be implemented by connecting a cylinder to the lower wire guide device 4 in the same way as the upper wire guide device 3 so that it can be opened and closed. Automatic wire feeding similar to the example is possible.

In the above embodiment, the feeding direction of the wire electrode 7 was set in the direction of the arrow 10 shown in FIG. Also, wires can be automatically supplied in the same manner as in the above embodiment.

In the above embodiment, the upper wire guide device 3 can be opened and closed by driving the cylinders 5 and 6, but as shown in FIG. A roller 32 having a diameter of 35 is provided to bring the two into close contact, and a motor 33
By driving the roller 32, the roller 32 is rotated so as to be in the state shown in FIG. 3 during machining, and in the state shown in FIG. 4 when the wire passes through the pick-up line after the wire is broken, thereby making it possible to automatically feed the wire in the same manner as in the above embodiment. Furthermore, the division of the wire guide devices 3 and 4 is not limited to two divisions, and the guide pieces may have a shape other than the one shown in the figure, such as having a round hole divided into a plurality of pieces. It may be one having an engaged V-shaped groove.

The pickup member feeding mechanism shown at 21 and 22 may be a mechanism having a pinch roller or a linear guide.

As described above, according to the present invention, when the wire is broken or cut, the workpiece is placed at the processing start position and the wire guide device is removed from the guide position, and at least the tip of the pick-up member of the wire is moved to the wire guide device. and the workpiece, the wires are attached to the pick-up members on both sides of the workpiece, and the pick-up members are wound and collected together with the wire, so that the wire is fed beyond the workpiece and the wire guide device. Therefore, the wire supply after the wire is disconnected or cut can be automatically ensured, and the wire pick-up member is wound up and collected together with the connected wire, which simplifies the device.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the automatic wire feeding device according to an embodiment of the present invention during processing, FIG. 2 is a perspective view showing the operation after wire breakage, and FIG. 3 is a perspective view showing another embodiment of the invention. FIG. 4 is a perspective view of the upper wire guide device during processing, and FIG. DESCRIPTION OF SYMBOLS 1...Workpiece, 2...Start hole, 3...Upper wire guide device, 4...Lower wire guide device, 5, 6...Cylinder, that is, guide operation mechanism, 6...Cylinder, 7...Wire Electrode, 13...
... roller, 14 ... roller, 20 ... pick-up member,
18...Pulse motor, 21, 22... Picking member operating mechanism, 41, 42... Mounting means.

Claims (1)

[Claims] 1 It has a pair of wire guide devices with a workpiece interposed between them, guides the wire with both wire guide devices, and generates an electric discharge between the wire and the workpiece while controlling the relative position of the wire and the workpiece. a guide operation mechanism for moving a wire guide device to remove the guide position in a device that processes a workpiece by moving the wire guide device;
a pick-up member for the wire; a pick-up member operating mechanism for feeding at least the tip of the pick-up member past the wire guide device and the workpiece; a pair of attachment means for respectively attaching the wire to the pick-up members on both sides of the workpiece; At the time of wire breakage or cutting, with the workpiece placed at the machining start position and the wire guide device removed from the guide position, at least the tip of the pick-up member of the wire is fed past the wire guide device and the workpiece, and the wire is cut on both sides of the workpiece. An automatic wire feeding device for a wire cut electrical discharge machine, wherein wires are attached to the pick-up members, the pick-up members are wound together with the wires, and the wires are fed over the workpiece and the wire guide device.