JPS62107922A - Wire-cut electric discharge machine - Google Patents

Abstract

PURPOSE:To make it possible to carry out a high-accurate machining process at a relatively high speed, by forming at least three guide projections on the inner peripheral surface of an annular member which is arranged such that at least one of wire guides is located in the vicinity of a workpiece so that the projections guide the outer peripheral surface of the wire electrode. CONSTITUTION:The outer peripheral surface of a wire electrode 13 is guided at least three points by a wire guide 21 having at least three projections 32 through 34 which are formed on the inner peripheral surface of an annular body 31, and therefore, the passing position of the wire electrode 13 may be set. Further, the wire electrode 13 is guided in the extreme vicinity of a workpiece 14 by means of the guide projections 32 through 34 by allowing the one end of the body 31 approach the workpiece 14, and therefore, vibration of the wire electrode 13 may be effectively restrained. Further, when electric discharge machining liquid is fed along the wire electrode 13 from above the wire guide 21, the liquid flows into a space 36, and is led into spaces 37 through 39, thereby it is possible to effectively feed the machining liquid into the electric discharge machining gap.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a wire-cut electrical discharge machine.

(Prior Art) Generally, in a wire-cut electrical discharge machine, in order to allow the wire electrode to run stably along a predetermined path when the wire electrode is being fed out in the axial direction, A pair of wire guides are provided with the object sandwiched therebetween. FIG. 1 shows the main parts of this type of conventional wire-cut electric discharge machine. Wire cut electric discharge machine
A pair of wire guides 2.3 formed as columnar members with a semicircular cross section are arranged to sandwich a workpiece 4, and wire electrodes are provided on each arcuate surface 2a and 3a of the wire guides 2.3. Grooves 2b and 3b for guiding 5
is formed. Wire electrode 5 that is continuously fed out
is supplied while being guided by these grooves 2b and 3b, and as a result, the vibration of the wire electrode 5 between the wire guides 2 and 3 is suppressed, making it possible to stably process the workpiece 4. . In the wire-cut electrical discharge machine, an appropriate electrical discharge machining fluid is supplied to the machining gap G from a machining fluid supply nozzle (not shown).

(Problem to be Solved by the Invention) By the way, in a wire-cut electric discharge machine, in order to ensure stability of the running of the wire electrode 5 in the machining gap G, the wire guide 2.3 is moved as close to the workpiece 4 as possible. It is hoped that However, in the electrical discharge machine 1 using the wire guides 2 and 3 configured as shown in FIG. 2.3 is the wire electrode 5
There is a limit to the shortening of the distance from the point of sliding contact with the workpiece 4. Furthermore, in order to efficiently supply the electrical discharge machining fluid to the machining gap G, a wire-cut electrical discharge machine has been considered in which a funnel-shaped electrical discharge machining fluid guide member 6 is provided to surround the upper wire guide 2. When such an electric discharge machining fluid guide member 6 is provided, the wire guide 2 tends to move further and further away from the workpiece 4, making it difficult to maintain the stability of the wire electrode 5 during running.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a wire-cut electrical discharge machine that can guide a wire electrode very close to a workpiece and also efficiently supply electrical discharge machining fluid to an electrical discharge machining gap. It's about doing.

(Means for Solving the Problems) The configuration of the present invention for achieving the above object includes a pair of wire electrodes disposed on both sides of the workpiece along the feeding direction of the wire electrode to guide the wire electrode. In a wire-cut electrical discharge machine equipped with a wire guide, at least one of the wire guides guides an annular member disposed close to the workpiece and an outer circumferential surface of the wire electrode at at least three points. at least three guide protrusions provided on the inner peripheral surface of the annular member for determining the passing position,
The present invention is characterized in that the electrical discharge machining fluid passes through the inside of the annular member and is applied to the electrical discharge machining gap.

(Function) The outer circumferential surface of the wire electrode is guided at at least three points by the wire guide having at least three guide protrusions provided on the inner circumferential surface of the annular member, thereby determining the passing position of the wire electrode. The support protrusion is provided on the inner peripheral surface of the annular member, and by bringing one end surface of the annular member close to the workpiece, the wire electrode is guided very close to the workpiece by the guide protrusion, and the vibration of the wire electrode is reduced. can be effectively suppressed. Furthermore, when electrical discharge machining fluid is supplied along the wire electrode from above the wire guide, the electrical discharge machining fluid is guided by the annular member and passes through the space formed by the guide protrusion and the annular member into the machining gap. Efficiently supplied.

(Embodiment) FIG. 2 is a block diagram schematically showing the structure of an embodiment of a wire-cut electrical discharge machine according to the present invention. The wire cut electrical discharge machining machine 1 is a device for performing electrical discharge machining on a workpiece 14 using a wire electrode 13 supplied from a supply bobbin 12.
The supply bobbin 12 is supported by a moving table (not shown) which is provided so as to be movable in a plane perpendicular to the feeding direction of the electric discharge machine 11. On the other hand, the supply bobbin 12 is attached to a frame (not shown) of the electric discharge machine 11. The wire electrode 13 is unwound from the supply bobbin 12 by the feed roller 15, and taken up by the take-up roller 18 via the upper energized roller 16 and the lower energized roller 17, whereby the wire electrode 13 is wound with the feed roller 15 with a predetermined tension. The used wire electrode 13 is stretched between a take-up roller 18 and wound around a take-up bobbin 19.

Electric discharge machining gap 2 between workpiece 14 and wire electrode 13
In order to allow the wire electrode 13 to run stably at 0, a pair of wire guides 21 and 22
The workpiece 14 is disposed along the line 3 so as to sandwich the workpiece 14 therebetween.

As shown in FIGS. 3 and 4, the wire guide 21 includes an annular main body 31 made of super steel and an inner peripheral surface 31 of the main body 31 for guiding the wire electrode 13 penetrating the main body 31.
It has three guide members 32 to 34 provided at a. The guide members 32 to 34 are each made of sapphire to ensure wear resistance, and the middle electrode 13 is guided at three points at the tips of these members. As can be seen from FIG. 4, the main body 31 has a flat shape, and the main body 3I can be placed very close to the workpiece 14, so that the wire electrode 13 can be moved between the three guide members 32 and 3.
4, the workpiece 14 can be guided near the pole (nearby). In the illustrated embodiment, a peripheral wall 35 for receiving and receiving electrical discharge machining fluid is vertically provided at the upper part of the main body 31, and a machining fluid tank is provided. When the electrical discharge machining fluid 42 in the main body 31 is sucked up by the pump 43 and flows from the nozzle 44 into the space 36 formed by the peripheral wall 35 and the main body 31, the electrical discharge machining fluid flows into the spaces 37, 38, . Guided within 39,
It is efficiently supplied into the electrical discharge machining gap 20.

The main parts of the other wire guide 22 have almost the same structure as the wire guide 21 described above, but as shown in FIG. is supplied into a housing 46 provided in the wire guide 22, and the electrical discharge machining fluid in the housing 46 overflows from the inner space of the annular body of the wire guide 22, which corresponds to the body 31 of the wire guide 21, and forms the discharge machining gap. The wire guide 2 is configured to be supplied to the wire guide 20.
It is different from 1. Note that the housing 46 is provided with a through hole 46a through which the wire electrode 13 passes;
Since the opening area of a is significantly smaller than the area of the space in the annular body, most of the electrical discharge machining fluid that has flowed into the housing 46 is supplied to the machining gap 20 through the annular body.

In addition, in FIG. 2, the reference numeral 51 indicates a processing pulse power source, one of whose output terminals is connected to the workpiece 14.
The other output terminal is connected to the energizing roller 16,1.
7, thereby applying a required processing pulse between the workpiece 14 and the wire electrode 13.

According to such a configuration, the wire electrode 13 is unwound from the supply bobbin 12 toward the take-up bobbin 19 at a predetermined speed, and at this time, the wire electrode 13 is unwound by a processing pulse applied between the wire electrode 13 and the workpiece 14. Electric discharge machining progresses in the electric discharge machining gap 20, and the workpiece 14 is machined into a desired shape. In this case, the wire electrode 13 is moved by a pair of wire guides 21 and 22 disposed close to the workpiece 14.
Since the wire electrode 13 is guided very close to the workpiece 14, the vibrations caused by the feeding of the wire electrode 13 are suppressed very effectively. As a result, the so-called corner sagging phenomenon that normally occurs in a part of the corner can be effectively suppressed, making it possible to perform processing with higher precision and to increase the feeding speed of the wire electrode. Furthermore, since the electrical discharge machining fluid is effectively guided to the machining gap 20 through the space formed inside the annular body of the wire guide, a good electrical discharge machining state can be maintained. Therefore, according to the apparatus of the present application, machining accuracy and machining speed are improved compared to conventional apparatuses, and experiments have confirmed that the machining speed is improved by about 10%.

In the above embodiment, the main bodies of the wire guides 21 and 22 were made of cemented carbide and the guide members were made of sapphire, but the present invention is not limited to these materials. For example, the guide members may be made of other materials with high hardness ( For example, it may be made of diamond, etc.).

(Effects) According to the present invention, as described above, the wire electrode can be guided very close to the workpiece, so the vibration amplitude of the wire electrode can be suppressed to a sufficiently small level, and the wire electrode can be guided very close to the workpiece. Since the electrical discharge machining fluid can be sufficiently and effectively supplied to the electrical discharge machining gap, an excellent effect is achieved in that accurate machining can be performed at a relatively high speed.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of a conventional wire-cut electrical discharge machine, FIG. 2 is a schematic configuration diagram schematically showing the structure of a wire-cut electrical discharge machine according to the present invention, and FIG. 3 is similar to FIG. FIG. 4 is an enlarged plan view of the wire guide shown, and FIG. 4 is a sectional view taken along the line A--A in FIG. 3. DESCRIPTION OF SYMBOLS 11... Wire cut electric discharge machine, 13... Wire electrode, 14... Workpiece, 20... Electric discharge machining gap,
21.22... Wire guide, 31... Main body, 31
a...Inner peripheral surface, 32, 33.34... Guide member.

Claims (1)

[Claims] 1. A wire-cut electric discharge machine equipped with a pair of wire guides disposed on both sides of a workpiece along the feeding direction of the wire electrode to guide the wire electrode, at least one of the wire guides is connected to the an annular member disposed close to the workpiece; and at least three guide protrusions provided on the inner circumferential surface of the annular member for guiding the outer circumferential surface of the wire electrode at at least three points and determining its passing position. A wire-cut electric discharge machine comprising: an electric discharge machining fluid passing through the inner side of the annular member and being applied to the electric discharge machining gap.