JPH0543444B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a scrap holding method and device in a wire-cut electric discharge machining apparatus, and particularly to a scrap holding method and apparatus thereof, in which a wire-cut electric discharge machining unit and a suction device supply attachment/detachment unit share a machining table. The cutting of the workpiece and its scrap by wire cut electric discharge machining is interrupted by a rigid body unit having a first suction part that adheres to the workpiece and a second suction part that adheres to the free part of the workpiece, that is, the scrap. The present invention relates to a method and apparatus for holding a scrap, which comprises holding the scrap and then cutting the remaining portion.

[Background of the invention, prior art]

Generally, as machining progresses in a wire-cut electric discharge machining apparatus, loose parts or scraps are generated. Therefore, as the part where the scrap and the workpiece are connected gradually decreases, the scrap will sag downward due to its own weight, causing undesirable contact with the wire electrode and resulting in poor processing conditions. The problem arises that the wire electrode becomes unstable or breaks. For this reason, in the past, when the above-mentioned unfavorable condition occurred or just before the occurrence, measures were taken such as forcibly removing the scrap by hand or supporting the scrap so that it would not move. However, these methods have a problem in that they must be performed manually. Furthermore, a wire-cut electrical discharge machining device has been proposed which is equipped with means for automatically sequentially arranging permanent magnets so as to straddle the cutting groove and connect with the scrap and the fixed workpiece portion as the cutting process progresses. However, this proposal also had the drawback that it required manual work to remove the permanent magnets and scrap, making it impossible to perform the primary processing and finishing processing continuously and automatically.

Furthermore, a method has been proposed in which a rigid body unit equipped with an electromagnet is fixed to a workpiece and its scrap using a robot, but this method has drawbacks such as requiring an expensive means called a robot.

[Purpose of the invention]

The purpose of this invention is to eliminate the above-mentioned drawbacks, and to provide a scrap holding method for holding scraps of a workpiece produced by wire cut electrical discharge machining, the workpiece is cut to a position where a predetermined cutout portion is left. With the wire electrode cut (or without cutting), move the processing table on which the workpiece is placed to the position of a suction device supply attachment/detachment unit such as a magnet supply attachment/detachment unit, and use a rigid body unit equipped with an attraction part such as an electromagnet. To provide a scrap holding method in a wire cut electrical discharge machining apparatus, in which the scrap is held on a workpiece, returned to its original position, and the remaining portion is cut, and a scrap holding device for carrying out the scrap holding method. It is. Hereinafter, for ease of understanding, the suction device supply attachment/detachment unit and the suction section will be referred to as a magnet supply attachment/detachment unit and an electromagnet, respectively. Note that the adsorption is not limited to magnets or electromagnets, and electrostatic adsorption means can also be used.

[Example - Configuration]

An embodiment of the present invention will be described in detail with reference to the drawings. In FIG. 1, a combination device of a wire cut electrical discharge machining unit 2 and a magnet supply attachment/detachment unit 3 according to the present invention is indicated generally by the reference numeral 1. The main body of the wire-cut electric discharge machining unit 2 and the main body of the magnet supply attachment/detachment unit 3 are installed on the machine stand 26, and the machine stand 26 also has a A Y-axis moving table 5, which is moved by a control motor 10, is slidably attached to a machine base 26. There is an X on the Y-axis moving table.
An X-axis moving table 4, which is moved in the axial direction (parallel to the plane of FIG. 1) by a control motor 9, is movably attached to the table 5. Four table supports 27 are provided at the four corners of the X-axis moving table 4, and the processing table 8 is attached to the X-axis moving table 4 via the table supports 27. Therefore,
The processing table 8 can be moved in orthogonal X and Y axes directions by control motors 9 and 10.

A hole 32 through which the wire electrode 12 passes is formed in the processing table 8, and a side plate case 3 is formed on the upper surface of the processing table 8 to surround the hole 32.
1 is installed. A workpiece 11 is set on a processing table 8 within a side plate case 31. The wire electrode 12 is fed from a wire electrode supply roller 13 through a tension roller 14 to a wire cutting region of the workpiece 11. Control motors 19, 2 in the X-axis direction and Y-axis direction
0 allows the upper guide 15 to be moved in the orthogonal X and Y axis directions, and the inclination angle of the wire electrode 12 can be adjusted according to the workpiece 11. The wire electrode 12 advances from the upper guide 15 through the workpiece 11 and the hole 32 of the processing table 8 to the lower guide 16, passes through the tension roller 17, and is wound onto the scrap roller 18. Workpiece 11
When wire cut processing is performed, wire electrode 1
2 and the workpiece 11 to be cut with, for example, pure water. The side plate case 31 is provided to prevent the pure water from scattering.

A mounting support 6 is fixed to the end of the Y-axis moving table 5 extending to the magnet supply detachable unit 3 side, and the mounting support 6 and the machining liquid collection table 7 form an inverted L-shaped cantilever. is formed. The free end 34 of the machining liquid collection platform 7 is inserted between the table supports 27 supporting the process table 8, that is, between a pair of table supports 27, 27 located in the Y-axis direction. Therefore, when the X-axis moving table 4 moves in the X-axis direction, the machining table 8 is configured to be able to slide on the machining liquid collecting table 7 in the X-axis direction. This machining liquid collection table 7 is particularly useful when the magnet supply detachable unit 3 is used as a die-sinking electrical discharge machining unit, but in this invention it can play the role of reliably holding the machining table. That is what it is. The magnet supply attachment/detachment unit 3 has a rigid unit supply head 24 which can be moved up and down and to which a rigid unit mounting body 25 can be attached. The rigid body unit mounting body 25 is attached to the rigid body unit 2.
3 is provided with an electromagnet energized by an electromagnet lead wire 28 so that it can be detachably attached.

Next, the rigid body unit 23 will be explained with reference to FIGS. 2 and 3. The rigid body unit 23 is
For example, electromagnets 21 and 22 are embedded in a main body molded from a non-magnetic material such as aluminum (ferromagnetic material is partially embedded) at a predetermined interval and with the magnetic poles located on the bottom surface of the main body. It is what was done. Third
As shown in the figure, the electromagnets 21 and 22 are controlled via an electromagnet lead wire 29, and the electromagnets 21 and 22 are configured so that they can be controlled individually and independently. Note that Fig. 3A is a cross-sectional view;
Figure B shows a bottom view taken along arrow A-A' in Figure 3A. The electromagnets 21 and 22 include an electromagnetic coil 3 at the center of a magnetic core 36 having a U-shaped cross section, for example.
5 is wound, and the electromagnetic coil 35 is connected to the electromagnet lead wire 29.

Next, the operation of holding or removing scrap 30 generated during electrical discharge machining by the wire cut electrical discharge machining unit 2 using the scrap holding device according to the present invention will be described with reference to FIG. Figure 2 shows
For example, the operation will be explained when the wire electrode 12 is used to cut the workpiece 11 along a closed loop of a predetermined shape, such as when machining a bearing hole in a die. When performing electric discharge machining using a wire cut electric discharge machining device, a machining start hole is provided in advance in the workpiece 11, and cutting is started from the machining start hole. The reference numeral a in the figure is the position where the machining start hole is provided, that is, the machining start position. Therefore, the cutting process by the wire electrode 12 is started from the process start position a, and is performed along a predetermined closed loop (rectangular in the drawing), for example, along the direction of the arrow. Then, the cutting process progresses as shown in the figure, and the wire electrode 1
2 reaches a predetermined set timing position b of the rigid body unit 23, the rigid body unit 23
is placed in a predetermined position as shown in FIG.
is powered and energized. The mounting position of the rigid body unit 23 is the position where cutting has already been completed, and the electromagnet 21 is on the scrap 30, and the electromagnet 22,
22 is on the fixed part of the workpiece 11,
Furthermore, both the electromagnets 21 and 22 are predetermined at positions where they do not straddle the cutting groove 33. In this way, the scrap 30 is attracted by the electromagnet 21, and the electromagnets 22, 22 are also attracting the fixed part of the workpiece 11, so that the cutting process further progresses and the wire electrode 12 completes the process. Even when the scrap 30 is released from the fixed portion of the workpiece 11 upon reaching the position c, the scrap 30 is held by the electromagnet 21 without moving.

Furthermore, when removing the scrap 30 to the outside,
If only the electromagnet 21 of the rigid body unit 23 is kept in the energized state and the electromagnets 22 and 22 are controlled to be in the de-energized state, then the rigid body unit is returned to the rigid body unit mounting body of the magnet supply detachable unit 3, and the scrap 30 is removed. can be excluded from the workpiece 11. Therefore, according to the present invention, by making it possible to freely retain and remove scrap during electrical discharge machining using a wire cut electrical discharge machining device, all machining including not only primary cutting but also secondary cutting can be performed. This makes it possible to completely automate the process.

In addition, at the position of the rigid body unit supply head 24 of the magnet supply attachment/detachment unit 3, there is, for example, a die-sinking electrical discharge machining electrode (not shown) used for shape electrical discharge machining.
If it is attached, die-sinking electrical discharge machining can be performed simply by moving the movable table after processing by wire cut electrical discharge machining.
In such a mode of use, the magnet supply attachment/detachment unit 3 will be called a die-sinking electrical discharge machining electrode attachment/detachment unit.

[Example - Effect]

The scrap holding method in the wire cut electric discharge machining apparatus according to the present invention and the operation of the apparatus will be described in detail.

First, the workpiece 11 is placed and set in the side plate case 31 on the processing table 8. Then,
The machining table 8, the X-axis direction moving table 4 and the Y-axis direction moving table 5 are driven by control motors 9 and 10 to move the wire cut electric discharge machining unit 2.
move it to the specified position. The wire electrode 12 fed out from the wire electrode supply roller 13 is passed through the processing start hole a of the workpiece 11 and set so as to be wound around the scrap roller 18. In this state, the wire cut electric discharge machining unit 2 is driven to cut the workpiece 11 in the direction of the arrow (see Fig. 2), and when the wire electrode 12 reaches the predetermined set timing position b of the rigid body unit 23, Driving of the wire cut electrical discharge machining unit 2 is stopped. The wire electrode 12 is fed out or slackened without being cut, and the X-axis moving table 4 is moved to the
The machining table 8 is moved in the axial direction and therefore
to the magnet supply attachment/detachment unit 3 side. Next, the magnet supply attachment/detachment unit 3 is driven to lower the rigid body unit supply head 24, and the rigid body unit 23, which is attracted to the electromagnet of the rigid body unit attachment body 25 fixed to the rigid body unit supply head 24, is moved onto the workpiece 11. Place it on.
In this case, the electromagnet 21 of the rigid body unit 23 is placed on the scrap 30 of the workpiece 11, and the electromagnets 22, 22 of the rigid body unit 23 are placed on the workpiece 11 (see FIG. 2). Then,
Power is supplied to the electromagnet lead wire 29 to connect the electromagnets 21 and 2.
2 and 22 are energized. Therefore, the rigid unit 23 attracts the scrap 30 to the workpiece 11 in a fixed manner. Next, the power supply to the electromagnet lead wire 28 is stopped, and the rigid body unit 23 is separated from the rigid body unit mounting body 25. Next, the control motor 9 is driven to move the X-axis direction moving table 4, and hence the machining table 8, to the wire cut electric discharge machining unit 2, so that the wire cut electric discharge machining can be performed. Next, the wire electrode 12 is tensioned, the wire cut electric discharge machining device is driven,
Wire cut electric discharge machining is performed again from the set timing position b of the workpiece 11 to the machining end position c, and the scrap 30 is completely separated from the workpiece 11. Then, the wire electrode 12 is cut, and the processing table 8 is reattached to the magnet supply attachment/detachment unit 3.
the electromagnet 2 of the rigid body unit 23.
2 and 22 are demagnetized, the electromagnet of the rigid unit mounting body 25 is energized to attract the rigid unit 23, and the rigid unit supply head 24 is raised. As a result, the scrap 30 remains attracted to the electromagnet 21 of the rigid unit 23, so that the scrap is extracted from the workpiece 11 and removed. The workpieces 11 subjected to electric discharge machining are collected at a predetermined location, the machining table 8 is again moved to the position of the wire cut electric discharge machining unit, and the next workpiece is placed and set on the machining table 8. On the other hand, after the processing table 8 is moved from the magnet supply attachment/detachment unit 3, the electromagnet 21 of the rigid body unit 23 is demagnetized,
The scrap 30 is separated from the rigid unit 23, and the scrap 30 is collected at a predetermined location. Of course, the removal of the scrap 30 and the workpiece 11 can also be done in other steps, for example, by removing and eliminating them before returning them to the magnet supply attachment/detachment unit 3.

〔Effect of the invention〕

As explained above, according to the present invention, it is sufficient to install the suction device supply attachment/detachment unit in parallel with the wire cut electric discharge machining apparatus, and there is no need to use a special device such as a robot. Furthermore, wire cut electrical discharge machining on the workpiece and attachment/detachment of the rigid body unit to the workpiece can be performed automatically.
Can be automated.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the scrap holding device in a wire-cut electric discharge machining apparatus according to the present invention, Fig. 2 is an explanatory diagram showing the positional relationship between the workpiece and the rigid unit, and Fig. 3 A and B are used for the rigid unit. It is an explanatory view showing an electromagnet. 2... Wire cut electric discharge machining unit, 3... Magnet supply attachment/detachment unit, 4... X-axis direction moving table, 5... Y-axis direction moving table, 8... Machining table, 11... Workpiece, 12... Wire electrode, 2
1, 22...Electromagnet, 23...Rigid body unit, 24...
Rigid unit supply head, 25... Rigid unit mounting body, 30... Scrap.

Claims (1)

[Claims] 1. A cutting process in which a workpiece is cut by wire cut electric discharge machining to a state where a predetermined cutout portion is left, and the workpiece is placed with or without cutting the wire electrode. a step of moving the processed table from the wire cut electric discharge machining unit to the position of the suction device supply attachment/detachment unit; a suction section that suctions the scraps of the workpiece cut in the cutting step; and a suction section that suctions the workpiece. a step of magnetizing and fixing with the electromagnetic coil a rigid unit having an electromagnetic coil that demagnetizes each of the attracting parts so as to be able to demagnetize the respective attracting portions, while straddling the scrap and the workpiece; returning the machining table on which the workpiece and the rigid body unit adsorbing it to the position of the wire cut electrical discharge machining unit; cutting the remaining portion of the predetermined cut portion of the workpiece; a cutting step of completely separating the workpiece from the scrap; a step of moving the separated scrap to the position of the suction device supply attachment/detachment unit while holding it in the rigid unit; Wire-cut electrical discharge machining characterized by at least the following steps: demagnetizing the electromagnetic coil that attracts the scrap; and separating the rigid unit from the workpiece while keeping the electromagnetic coil that attracts the scrap energized. Scrap retention method in equipment. 2. A wire-cut electric discharge machining unit and a suction device supply attachment/detachment unit that share an X-axis moving table and a Y-axis moving table capable of moving in orthogonal X and Y-axis directions, and one of the axial moving tables A processing table on which a workpiece is set is fixed to the suction device supply attachment/detachment unit, and a rigid body unit supply head that moves up and down and attaches a rigid body unit mounting body is provided, A rigid unit is removably attached to the body, and the rigid unit includes an adsorption part that adsorbs the workpiece, an adsorption part that adsorbs the scraps of the workpiece, and an electromagnetic unit that magnetizes each of the adsorption parts so that the respective adsorption parts can be demagnetized. 1. A scrap holding device in a wire cut electrical discharge machining device, characterized in that it has a coil.