JPH09174375A - Machine tool having electromagnetic wave shielding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably shield an electromagnetic wave entering and leaking from a clearance between a fixed cover to surround a machine tool and a door arranged in the fixed cover so as to be openable and closable. SOLUTION: A tubular shielding member 13 is arranged along the peripheral edge of an opening part 5 of a fixed cover 3 between the fixed cover 3 and a door 7, and a pressurized fluid is supplied in the tubular shielding member 13 by a fluid supply means 15, or the pressurized fluid is discharged from inside the tubular shielding member 13, and the tubular shielding member 13 is constituted so as to be expanded and contracted. Therefore, after the door 7 is closed, the tubular shielding member 13 is expanded, and after it is contracted, the door 7 is opened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool equipped with an electromagnetic wave shielding device which prevents electromagnetic waves from entering from outside and prevents generated electromagnetic waves from leaking to the outside. Here, the machine tool is, for example, an NC machine tool, an electric discharge machine, a laser machine, or the like.

[0002]

2. Description of the Related Art Generally, a machine tool radiates an interference electromagnetic wave through a power supply line, a motor, etc., and when no countermeasure against the interference electromagnetic wave is taken, it interferes with other equipment installed in the vicinity to cause an interference electromagnetic wave. May cause failure. In particular, in an electric discharge machine, there is a possibility that an electromagnetic wave may be radiated from the electric discharge machine part to cause radio interference in other devices installed nearby. In addition, there is a possibility that the control device of the machine tool may malfunction due to electromagnetic interference generated by another device installed near the machine tool. Therefore, there is a case where a means for shielding electromagnetic waves emitted from the machine tool or entering the other machine tool by housing the machine tool in the shield room is used. This shielded room is expensive, the crane cannot be used freely for setting the work, and the workability is not good.

The applicant of the present invention, Japanese Patent Laid-Open No. 5-1774
As shown in Japanese Patent Publication No. 52, there is an electric discharge machine equipped with an electromagnetic wave shielding device that electromagnetically shields the electric discharge machine area of the electric discharge machine. This is configured by forming a machining tank of an electric discharge machine with an electromagnetic wave shielding material, providing an upper shielding cover surrounding the bed, and providing a gap that allows relative movement in the X and Y axis directions with the machining tank. doing. Then, the action and effect of preventing the electromagnetic waves generated from the electric discharge machining unit from leaking to the outside are obtained. Furthermore, as a conventional technique, electromagnetic waves enter or leak through a gap between a cover that surrounds a machine tool and a door that is openably and closably provided in the opening of the cover. There is a shield material.

[0004]

In the technique disclosed in Japanese Unexamined Patent Publication No. 5-177452, which is described in the above-mentioned conventional technique, a gap is provided between the processing tank and the upper shield cover. There is a problem that a fault electromagnetic wave may leak or enter from an electric wire, which may cause a fault in other devices installed nearby. Also,
A sheet-shaped shield material that is sandwiched in the gap between the cover surrounding the machine tool and the door that can be opened and closed at the opening of the cover is rubbed and worn when the door is opened and closed after long-term use, and the shielding effect is improved. There is a problem of disappearing.

In view of the above problems, the present invention provides
A fixed cover that encloses the entire machine tool or partially surrounds the machine tool such as the processing area and control device is provided to shield electromagnetic waves from entering and leaking, and to secure the fixed cover and the door that can be opened and closed. An object of the present invention is to provide a machine tool equipped with an electromagnetic wave shielding device that shields electromagnetic waves that intrude and leaks through gaps and can reliably shield electromagnetic waves.

[0006]

To achieve the above object, the present invention provides a tubular shield member between the fixed cover and the door along the peripheral edge of the opening of the fixed cover or along the peripheral edge of the door. , The tubular shield member can be expanded and contracted by supplying pressurized fluid into the tubular shield member or discharging the pressurized fluid from within the tubular shield member, and then closing the door. Inflate the tubular shield member,
It is designed to open the door after it contracts. That is,
In a machine tool equipped with an electromagnetic wave shielding device that does not allow electromagnetic waves from entering and does not leak generated electromagnetic waves to the outside, a metal fixing cover that surrounds all or part of the machine tool, and the fixing An openable and closable door provided in the opening of the cover, and the peripheral edge of the opening of the fixed cover or the peripheral edge of the door between the fixed cover and the door, and the door by fluid pressure or Provided is a machine tool including an electromagnetic wave shielding device including a tubular shield member that can be in close contact with and separated from the fixed cover, and a fluid supply unit that supplies a pressurized fluid into the tubular shield member. The fixed cover referred to in the claims includes both the one surrounding the entire machine tool and the one surrounding the part of the machine tool such as the machining area and the control device.

[0007]

According to the present invention, a shield member is provided between the fixed cover and the door along the peripheral edge of the opening of the fixed cover or along the peripheral edge of the door so as to be brought into close contact with or separated from the door or the fixed cover by fluid pressure. Therefore, when the pressurized fluid is supplied into the shield member, the shield member expands and is brought into close contact with the fixed cover and the door, so that the shield is surely shielded. Further, when the pressurized fluid in the shield member is discharged, the shield member contracts to separate the fixed cover from the door, and the door can be opened and closed without rubbing the shield member.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a machine tool provided with an electromagnetic wave shielding device showing an example of an embodiment of the present invention, and FIG. 2 is a partially enlarged sectional view of a shield member provided between a fixed cover and a door. (A) is a contracted state, (b)
Indicates an expanded state. First, an example of an embodiment of the present invention will be described with reference to FIG. 1 by taking an electric discharge machine as an example. A metal fixed cover 3 is provided on the upper surface of the bed 1 of the electric discharge machine so as to surround the electric discharge machining area. An opening 5 is formed in the fixed cover 3 so that the crane or the like does not get in the way when a work is attached to a table (not shown) provided on the bed 1.

A door 7 is provided in the opening 5 of the fixed cover 3 by a guide rail 9 so as to be openable and closable in the left-right direction. The fixed cover 3 and the door 7 are always provided with windows 11 so that the state during processing can be monitored. The window 11 is made of one or a combination of a mesh of a conductive material having an electromagnetic wave shielding effect or a material containing a conductive material, for example, glass with a wire mesh, an acrylic resin plate, a wire mesh, or the like, and the fixed cover 3 Alternatively, it is electrically coupled to the door 7.

At the periphery of the opening 5 of the fixed cover 3, a tubular shield member 13 having an electromagnetic wave shielding effect is provided. A fluid supply means 15 is connected to the tubular shield member 13, and a pressurized fluid is supplied into the shield member 13 to expand and contract the shield member 13. FIG. 2 shows an example of the shield member 13 provided on the peripheral portion of the opening 5 of the fixed cover 3. As shown in FIG. 2A, an elastic tube 17 of the shield member 13 is covered with a shield material 19 which is a conductive thin spring plate attached to the fixed cover 3 and made of a highly flexible thin plate. When the door 7 is open, no pressurized fluid is supplied, so the elastic tube 17 is contracted, and the elastic tube 17 is pressed by the spring force of the shielding material 19.

As shown in FIG. 2 (b), when the door 7 is closed, pressurized fluid is supplied from the fluid supply means 15 to expand the elastic tube 17, and the shielding material covering the elastic tube 17 is covered. 19 deforms and contacts the door 7, and the fixed cover 3
The door 7 and the door 7 are electrically coupled to each other, so that the door 7 is reliably shielded. When the door 7 is opened, the pressurized fluid in the elastic tube 17 is discharged to contract the elastic tube 17, and the elastic tube 17 is pressed by the spring force of the shielding material 19 covering the elastic tube 17. . Therefore, the shielding material 19 is separated from the door 7, and the door 7 can be opened and closed. Also,
The pressurized fluid may be supplied to and discharged from the elastic tube 17 in association with a machining start command and a machining end command by the NC program when the electric discharge machine is automatically operated.

The fixed cover 3 has a door lock means 21.
Is provided close to the door 7. This door lock means 2
1, the door 7 is locked when the door 7 is closed and fluid pressure is supplied into the shield member 13, and the door 7 is locked when the fluid in the shield member 13 is discharged. It is supposed to be released. Thus, the door 7 is locked when the shield member 13 is inflated, the door 7 does not open carelessly, and the shield member 13 does not wear. Of course, when the door 7 is open, pressurized fluid is not supplied into the elastic tube 17, so
Also in this case, the shield member 13 is not worn.

In the above description, the shield member is provided at the peripheral portion of the opening of the fixed cover, but it may be provided at the peripheral portion of the door instead. The door can also be used in the case of a hinged door. Further, as the shield member, a combination of an elastic tube and a shielding material made of a flexible thin plate was used, but instead of this, an elastic tube containing a conductive material, a metal-plated elastic tube, a flexible metal An elastic tube covered with a mesh may be used. Although the electric discharge machine has been described in the present embodiment, the present invention can be applied to all machine tools such as other NC machine tools and laser beam machines.

[0014]

As described above, according to the present invention, by enclosing all or a part of a machine tool with a metal fixed cover, invasion and leakage of electromagnetic waves can be shielded, and furthermore, the fixed cover and the door. Since the shield member expands and contracts due to the pressurized fluid and can shield the fixed cover and the door without a gap, it is possible to reliably prevent the intrusion of electromagnetic waves from the outside and to generate the generated electromagnetic waves to the outside. It will not be leaked. Further, since the shield member can be contracted during the opening / closing operation of the door, the shield member does not rub against the door and is not worn.

[Brief description of the drawings]

FIG. 1 is a perspective view of a machine tool including an electromagnetic wave shielding device showing an example of an embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of a shield member provided between a fixed cover and a door, in which (a) shows a contracted state and (b) shows an expanded state.

[Explanation of symbols]

 1 Bed 3 Fixed Cover 5 Opening 7 Door 9 Guide Rail 11 Window 13 Shielding Member 15 Fluid Supply Means 17 Elastic Tube 19 Shielding Material 21 Door Locking Means

Claims (2)

[Claims] 1. A machine tool provided with an electromagnetic wave shielding device that prevents electromagnetic waves from entering from outside and does not leak generated electromagnetic waves to the outside, wherein a metal fixing surrounding all or part of the machine tool. A cover, an openable / closable door provided in the opening of the fixed cover, a peripheral edge of the opening of the fixed cover or a peripheral edge of the door between the fixed cover and the door, An electromagnetic wave shielding device comprising: a tubular shield member that can be brought into close contact with or separated from the door or the fixed cover by pressure; and a fluid supply unit that supplies a pressurized fluid into the tubular shield member. Equipped machine tools. 2. The tubular shield member comprises an elastic tube that can expand and contract, and a shielding material that is provided so as to cover the elastic tube and that deforms as the elastic tube expands and contracts. A machine tool provided with the electromagnetic wave shielding device according to 1.