JPH08215940A - Device and method for feeding working fluid for electric machining device - Google Patents

Abstract

PURPOSE: To make compact a machining fluid tank so as to further reduce a set area by merely using approximately the same amount of machining fluid as the machining fluid tank, and also make the supply, circulation, agitation, and discharge of the machining fluid efficiently. CONSTITUTION: Before machining is started, machining fluid in a machining fluid tank 2 is fed fast to a machining tank 1 so as to immerse a work to be machined. During the machining, solenoid valves V1, V2, and V5 are closed, V3 and V4 are opened and, at the same time, a pump P is driven to circulate the machining fluid through a piping B or agitate the machining fluid in the machining tank 1. At the same time, the machining fluid is fed to machining fluid injection nozzles 77 and 8 through a piping D, and injected during the machining intervals. Also a machining fluid level is detected by an upper float switch 4 so as to control the solenoid valves V3 and V4 and the pump P and maintain the machining fluid level at a specified limit. When the machining fluid in the machining tank 1 is discharged, the solenoid valves V3 and V5 are opened until a lower float switch 5 detects the absence of the machining fluid in the machininh tank 1, and the pump P is driven to discharge the machining fluid to the machining fluid tank 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes a discharge or electrolysis phenomenon generated between both electrodes by immersing a workpiece in a machining liquid and applying a predetermined voltage to a gap between the workpiece and a tool electrode. The present invention relates to a machining fluid supply device for an electromachining apparatus that performs machining by reducing the amount of machining fluid to be stored without reducing the machining performance in conventional machining, and the installation area is smaller. The present invention also relates to a working liquid supply apparatus and method with high work efficiency.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram showing a general example of a machining fluid supply device in a wire-cut electric discharge machine for dipping an object to be machined using a conventional oil-based machining fluid for electric discharge machining. is there. For other electro-machining equipment such as electrolytic machining equipment, only the parts that are considered necessary are described in the specification,
Detailed description is omitted.

Reference numeral 1 denotes a processing tank, which is mounted on a base via a table (not shown). The processing tank 1 is movable in the horizontal direction by driving the table, but there is also a structure in which the processing tank 1 is fixed.

The workpiece 3 is fixed on a mount (not shown) and installed in the processing tank 1. At least one wall surface of the processing tank 1 is openable so that the workpiece 3 can be put in and taken out.
Since the working fluid is filled so that the
It is configured to be liquid-tight by closely contacting the open parts so that the machining liquid does not leak out.

The processing tank 1 has a processing chamber 1A and a discharge chamber 1B formed of a dam plate 1C. Generally, the height of the dam plate 1C is adjusted to regulate the height of the machining liquid surface. I have to.

In order to send a clean machining fluid to the machining tank 1 while collecting the used machining fluid, the machining fluid tank 2 is
Sewage tank 2 that collects used processing liquid by partition plate 2C
Cleaning liquid tank 2B for re-supplying A and purified processing liquid
It is divided into Therefore, the working liquid tank 2 must store a predetermined amount or more of working liquid in advance, and must have a capacity sufficiently larger than the capacity of the working tank 1.

The pipe E is a drain, and the discharge 1 of the processing tank 1
B and the waste liquid tank 2A of the processing liquid tank 2 are connected via a drain valve DV. When the work is finished and the workpiece is taken out, the lower part of the dam plate 1C is opened, and the working liquid stored in the working chamber 1A of the working tank 1 passes through the pipe line E to the waste liquid tank. Two
It is discharged to A. Therefore, the waste liquid tank 2A must have a capacity that is substantially the same as or larger than the capacity of the processing tank 1.

The working liquid in the waste liquid tank 2A is pumped up by the pump DP and sent to the clean liquid tank 2C through the pipe line F. A filter device 6 is provided in the pipe line F, and processing waste and contaminants contained in the used processing liquid are filtered and removed. In order to prevent damage to the pump DP and to stabilize the flow rate of the working fluid sent by the pump DP, a relief valve provided with a relief valve RV is provided.

The working liquid stored in the clean liquid tank 2B is pumped up by the pump CP and supplied to the working tank 1.
Similar to the above, it has a relief conduit provided with a relief valve RV.

A machining fluid cooling device 9 cools the machining fluid stored in a state in which the temperature is raised by heat from machining to a predetermined temperature. When performing electric processing using a water-based processing liquid, the electric conductivity of the processing liquid changes with the processing. Therefore, a deionizer using an ion-exchange resin is installed in the cleaning liquid tank 2B to clean it. The working fluid in the liquid tank 2B is circulated to maintain the working fluid at a predetermined specific resistance value.

The conduit G is a liquid supply conduit provided for supplying the machining liquid to the machining tank 1 to the extent that the workpiece 3 is immersed in the machining liquid. Further, the conduit H is a machining liquid jet conduit provided for always supplying a clean machining liquid to the machining gap formed by the workpiece 3 and the tool electrode. Therefore, before the start of processing, the electromagnetic valve V6 for liquid supply is opened and the electromagnetic valve V7 for jet flow is closed so that the processing liquid is rapidly sent.

The pipe line H is branched on the way to the upper jet nozzle 7
And the lower jet nozzle 8. Therefore, the working fluid in the conduit H is maintained at a predetermined pressure via the jet flow regulating valve FV and supplied from the nozzles 7 and 8 as a working fluid jet.

Before starting the processing, the processing liquid is the processing liquid tank 2
Are stored in the processing tank 1, and the processing tank 1 is in a state where there is no processing liquid. When the workpiece 3 is fixed to the mount, the processing tank 1 is made liquid-tight, and the electromagnetic valve V6 for liquid transfer is opened.
The jet flow solenoid valve V7 is closed. Then, the pump CP is driven to expel the machining liquid to the machining tank 1.

The dam plate 1C is adjusted to a predetermined height according to the installation state of the workpiece 3, and when a predetermined machining liquid is fed, the machining liquid in the machining chamber 1A is changed to the dam plate 1C. Overflows into the discharge chamber 1B, so the machining fluid
There is no fear of spilling from the floor to the floor.

After a predetermined amount of working fluid is stored in the working tank 1 and the work piece 3 is immersed in the working fluid, the electromagnetic valve V6 for liquid delivery is closed and the electromagnetic valve V7 for jet flow is opened for machining. Make it possible. At this time, the working liquid supply system can be selected by appropriately operating the liquid feeding electromagnetic valve V6 and the jet flow electromagnetic valve V7. The two electromagnetic valves V6, V
It is also possible to open both 7 for processing. The range of selection of the supply system of the machining fluid is also influenced by the capacity of the pump and the members constituting the circuit such as the machining fluid adjusting mechanism. May not be used.

[0016]

Conventionally, since the conventional structure is generally as described above, a sufficiently large amount of the working fluid must be stored in the working fluid tank as compared with the working fluid tank. Larger size, more processing liquid, and a larger installation space are required. Further, the processing tank itself also needs a discharge chamber for overflowing and discharging the processing liquid, and therefore must be made larger accordingly.

On the other hand, for example, Japanese Patent Laid-Open No. 3-270
For example, by raising the working liquid tank as in the device disclosed in Japanese Patent No. 829, or by arranging the waste liquid tank and the clean liquid tank in steps as in the device disclosed in Japanese Patent Laid-Open No. 4-171123. ,
There has been proposed a device that reduces the installation floor area. However, even in these devices, the amount of the working liquid stored in the working liquid tank must be sufficiently larger than the capacity of the working tank, and the working liquid is additionally required. Further, in these devices, the working liquid tank is too high, and it is difficult to easily perform maintenance work such as replenishment, replacement or cleaning of the working liquid.

Further, the apparatus disclosed in Japanese Patent Publication No. 5-55254 has a structure in which the processing tank and the processing liquid tank are used in common. It is possible. The one that doubles as such a processing tank and a processing liquid tank was common even in the early electromachining apparatus. However, since the processing liquid and the processing liquid tank are used together, the purification of the processing liquid in the processing tank is insufficient, and the processing performance deteriorates as the processing accuracy deteriorates as the processing progresses. Has the drawback that it also deteriorates rapidly. Also, in order to attach the work piece etc.,
There is a problem that the structure is complicated.

Further, in the electric discharge machining among the electric machining, there are cases where fine powder is mixed in the machining liquid to perform the machining. In this case, the known device described above cannot cope with the machining. It was necessary to install a processing liquid tank for powder processing as disclosed in JP-A-2-30423.

Besides, various devices for saving space have been proposed, such as the devices disclosed in JP-A-4-310319 and JP-A-6-57525.
However, the structure was complicated, and the processing performance, work efficiency, and maintainability were deteriorated.

The machining fluid supply apparatus of the present invention has poor maintainability due to deterioration of machining performance due to insufficient purification of the machining fluid, extremely high machining fluid tank or complicated structure. Can be reduced and the amount of processing fluid used can be reduced without degrading the time until the processing fluid is fully loaded in the processing tank or the efficiency of regenerating and supplying the used processing fluid, thus reducing the installation area. That is the purpose.

[0022]

In order to achieve the above object, a machining fluid supply apparatus of the present invention is a machining fluid for an electric machining apparatus configured to immerse a workpiece in the machining fluid for machining. In the supply device, a machining tank, a machining fluid tank capable of storing a machining fluid of substantially the same volume as the machining tank, a first valve and a second valve.
A first conduit for supplying the working liquid from the working liquid tank to the working tank via the valve of No. 2 and a second pipe for circulating the working liquid of the working tank via the third valve and the fourth valve. And a filter device provided in the second pipeline, the third valve and the fifth pipeline.
And a common pump provided in each of the first to third pipelines for discharging the machining fluid from the machining tank to the machining fluid tank via the valve. .

As another means, the above-mentioned machining is performed via a machining tank, a machining fluid tank capable of storing a machining fluid of substantially the same volume as the machining tank, and a first valve and a second valve. A first conduit for supplying the working liquid from the liquid tank to the working tank; a second conduit for circulating the working liquid in the working tank through a third valve and a fourth valve; A filter device provided in the second conduit, a third conduit for discharging the working liquid from the working tank to the working liquid tank via the second valve and the first valve, and the first Or a common pump capable of forward and reverse rotation provided in the middle of the third conduit.

Further, the above-mentioned valve is used as a control valve, and the first
To a common pump provided in the third pipe line, at least two liquid level detectors provided in the processing bath for respectively detecting the upper limit and the lower limit of the working fluid in the working bath, and the liquid level detector By providing the control device for controlling the control valve or the pump based on the detection signal of, the purpose can be achieved more effectively.

At this time, a more appropriate processing is performed by providing a fourth pipeline that is branched from the second pipeline that circulates the machining fluid in the machining tank and supplies a machining fluid jet to the machining gap. realizable. In the invention according to claims 5 to 8, a machining liquid jet adjusting device for adjusting the machining liquid jet is provided in the fourth pipeline. Further, the invention according to claim 9 to claim 11 is, in the second pipeline, a filter device or a filter device on the pipeline between the machining tank and a valve provided between the machining tank and the pump. A working fluid cooling device is provided. By applying in this way, it is possible to deal with a wider range of processing forms.

The machining liquid supply method of the present invention is an electric machining method in which a workpiece is immersed in the machining liquid for machining, and at least an amount of the machining liquid capable of immersing the workpiece in the machining tank is used. Is stored in a machining fluid tank having a volume approximately the same as that of the machining tank, and a valve provided in the middle of the first pipeline connecting the machining tank and the machining fluid tank is released and the pump is driven. Then, a step of supplying the working liquid in the working liquid tank to the working tank to immerse the workpiece in the working liquid, and applying a predetermined voltage to the workpiece and the tool electrode to process the workpiece. The step to be performed and the valve provided in the middle of the second pipeline connecting one part of the processing tank and another part of the processing tank during the processing are opened and the pump is driven to remove the processing liquid in the processing tank. A step of circulating and purifying dirty working fluid A step of opening a valve provided in the middle of a third pipeline connecting the processing tank and the processing liquid tank and driving the pump to discharge the processing liquid from the processing tank to the processing liquid tank. It is a thing.

[0027]

According to the apparatus of the present invention, the first working liquid is supplied.
And a second conduit for circulating and purifying the machining fluid,
Since the third pipeline for discharging the machining fluid shares a part of the pipeline, the machining fluid can be rapidly fed, circulated, stirred, and discharged by one pump. Then, when machining is performed, almost all the machining fluid in the machining fluid tank is supplied to the machining vessel through the first conduit, and during machining, it is used without returning to the machining fluid tank through the second pipeline. High efficiency because the working fluid is purified and re-supplied, or the working fluid in the working tank is agitated, and after processing, almost all the working fluid in the working tank is discharged to the working fluid tank by the third conduit. Supply of machining fluid with high accuracy,
Circulation, stirring and discharging are performed.

Therefore, the working liquid tank only needs to have a capacity approximately the same as that of the working tank, so that the installation area is reduced while no special structure is required. Moreover, since the equipment for supplying, circulating, stirring, and discharging the working fluid can be reduced, the installation area of the equipment is also reduced. Further, since the processing liquid is drained from the processing tank to the processing liquid tank by the pump, the height of the processing liquid tank can be increased and the installation area of the processing liquid tank can be reduced.

In particular, according to the apparatus described in claim 3 of the present invention, a liquid level detector is provided to control each control valve or pump so as to adjust the liquid level in the processing tank. Since the processing tank does not need a discharge chamber for overflow, the size of the processing tank can be further reduced, and there is no danger of overflow of the processing liquid. When supplying the machining fluid and purifying the circulation, the upper fluid level detector detects that the necessary machining fluid has been supplied to the machining tank and the feeding of the machining fluid is stopped. Since the surface detector detects that no unnecessary machining liquid remains in the machining tank and stops the discharge of the machining liquid, the machining liquid is supplied, circulated, stirred, and discharged with high efficiency.

By arranging the jetting line of the working fluid in a branched manner to the circulation duct, the jetting of the working fluid can be supplied with a simple structure, and only fine powder of a specific size or material is removed. By installing the obtained filter device on the circulation pipe, it can be used for electric discharge machining in which a specific powder is mixed in the machining liquid. Further, by providing the machining fluid cooling device on the circulation conduit, the machining fluid being machined can be maintained at a predetermined temperature and the machining environment can be maintained to perform accurate machining.

Further, according to the processing method of the present invention, the supply, circulation, agitation, and discharge of the processing liquid stored in the processing tank or the processing liquid tank can be efficiently performed without causing an overflow accident of the processing liquid. Since it can be performed properly, the amount of working liquid used can be substantially the same as the capacity of the working tank, and the installation area can be reduced.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an embodiment of a working fluid supply device in a wire cut electrical discharge machining apparatus for dipping a workpiece by using the oil-based machining fluid of the present invention to perform electric discharge machining. .

An object to be processed is installed in the processing tank 1 and immersed in the processing liquid. The processing tank 1 is provided with an upper float switch 4 and a lower float switch 5 as liquid level detectors, and when the processing liquid is fed before the start of processing and when the workpiece 3 being processed is immersed, The upper float switch 4 detects the upper limit. The upper float switch 4 can adjust the installation position within a predetermined range, and can set the liquid level of the machining liquid stored in the machining tank 1 according to the plate thickness of the workpiece 3.

In the embodiment, the working liquid tank 2 has a funnel-shaped lower portion, and has a structure in which the working liquid and dirt are unlikely to remain at the bottom. Further, in order to make the installation area smaller, the structure is relatively long with respect to the processing tank 1. Although the machining fluid tank 2 is described as being located below the machining tank overhead, the machining fluid is collected in the machining fluid tank 2 when the machining fluid is supplied from the machining fluid tank 2. Also in this case, since the pump P is used to deliver the liquid, the height of the processing tank 1 is not affected, and the processing tank 1 can be installed at a position suitable for the arrangement of the apparatus in consideration of the installation conditions. If the working fluid used is a water-based working fluid, carbon dioxide gas in the air will lower the specific resistance value and deteriorate it due to the growth of microorganisms. In the case of such processing, it is advisable to provide a lid-shaped member so that the upper part of the processing liquid tank 2 is normally closed.

The working tank 1 and the working liquid tank 2 have substantially the same amount or a slightly larger capacity than the working liquid tank 2. For example, the working tank 1
If the capacity of 200 liters is 200 liters,
It is preferable to configure it to be about 220 l.

The conduit A forms a first conduit as shown in FIG. 2 (1), and basically 2 conduits are formed on the conduit.
One solenoid valve (control valve) V1 and V2, and one pump P
Is provided. The first pipeline is a machining fluid supply pipeline for supplying the machining fluid stored in the machining fluid tank 2 to the machining tank 1. Normally, when there is no machining fluid in the machining tank 1, It is used when the working fluid is expeditedly fed and the working fluid is quickly stored in the working tank 1 so that the workpiece 3 is immersed in the working fluid.

The conduit B forms a second conduit as shown in FIG. 2B, and basically 2 conduits are formed on the conduit.
One solenoid valve V3 and V4, one pump P, and a filter device 6 are provided. The second pipeline mainly discharges the dirty used working fluid from the working tank 1 once to the outside of the working tank 1, purifies the dirty working fluid containing the processing waste, and again works the working tank 1 again.
It is used as a working fluid circulation line for returning to. Also,
In the so-called powder processing, in which processing is performed using a processing liquid in which a predetermined amount of fine powder is mixed with the liquid, it is also used to stir the processing tank in order to prevent the mixed fine powder from settling.

Therefore, according to this configuration, the pump P
Is located on the pipeline A, and is shared with the pump for expediting the machining liquid from the machining liquid tank 2 to the machining tank 1. A machining liquid cooling device 9 is provided in this pipe line as needed to cool the machining liquid whose temperature has risen due to heat generated by the machining or supply pump to a predetermined temperature.

The conduit C forms a third conduit as shown in FIG. 2C, and basically 2 conduits are formed on the conduit.
One solenoid valve V3 and V5 and one pump P are provided. The electromagnetic valve V2 is common with the valve of the pipeline B, and the pump P is common with the liquid feed pumps of the pipeline A and the pipeline B. The third pipeline is a drainage pipeline for returning the machining fluid in the machining tank 1 to the machining fluid tank 2. The discharge port provided in the machining tank 1 is the supply of the machining fluid in the pipeline A. Same as the mouth,
Therefore, the processing tank 1 does not need to be provided with a drain port exclusively for discharging the processing liquid.

The pipe D forms a fourth pipe branching from the second pipe as shown in FIG. 2B, and the strength of the machining fluid jet is adjusted on the pipe. A machining fluid jet adjusting device 10 including a throttle valve and a check valve for performing the operation is provided. At this time, the nozzles 7 and 8 for jetting the machining liquid on the pipe line
A sensor for detecting the pressure or the flow rate of the jet flow may be provided, and the flow rate adjusting valve may be controlled to automatically adjust the strength of the machining fluid jet.

The machining fluid control device 11 is connected to each solenoid valve, a pump, and a vertical float switch. Then, by inputting signals from the operation switch device 12 having a plurality of control switches or the upper and lower float switches 4 and 5, control signals O1 to O7 are output according to the purpose of supplying, circulating, stirring, or discharging the working fluid. However, the opening and closing of the solenoid valves V1 to V5 and the driving and stopping of the pump P are controlled. In the case of a device equipped with an NC device, the NC
The command signal from the NC device may be converted into a control signal by a command based on a program to control each control valve and pump, which is useful when performing automatic machining or unmanned operation.

FIG. 3 is a flow chart for explaining the operation of the control device, and the operation of the control device 11 in this embodiment described above will be described below.

When the power of the control device 11 is turned on, a plurality of switches on the operation switch device 12, the machining liquid supply switch, the machining liquid circulation switch, and the machining liquid discharge switch are turned off (S1). Further, all the solenoid valves V1 to V5 are closed and the pump P is stopped.
Alternatively, the state is confirmed (S2).

When the workpiece is installed in the processing tank 1 and the processing liquid is supplied to the processing tank 1, the processing liquid supply switch of the operation switch device 12 is pressed (S3). When the supply switch is pressed (S4), the control device 11
Outputs control signals O1, O2, O6 to open the solenoid valves V1 and V2 and drive the pump P (S
5). As a result, the working liquid in the working liquid tank 2 is sent to the working tank 1 through the first pipeline A.

At this time, the plurality of switches are configured so as not to be in the input state at the same time, and when other switches are input, the machining liquid supply switch is turned off to stop the liquid supply (S1). Then, after temporarily closing all the solenoid valves and stopping the pump (S2), the solenoid valve and the pump are controlled based on the switch command input later.

After that, when the upper float switch 4 which is set to a required height in advance detects the machining liquid surface and outputs the detection signal I1 (S6), the control device 11 controls the control signal O1 based on the signal I1. O2 and O6 are output to close the solenoid valves V1 and V2 and stop the pump P (S7). Then, the machining liquid supply switch is turned off (S1). Because of this, the working fluid is
Even if the machining fluid supply switch is input while the fluid is stored in the tank, the operation of sending the fluid from the machining fluid tank 2 to the machining tank 1 is immediately stopped, and no accident such as overflow of the machining fluid or idle operation of the pump occurs. .

Next, when machining is performed with the machining fluid stored in the machining tank 1, the machining fluid circulation switch of the operation switch 12 is pressed (S2). As described above, since the other switches are in the off state at this time, when this machining liquid circulation switch is input (S8), the control device 11
Input the detection signal I1 from the upper float switch 4,
It is detected whether the processing liquid is stored in the processing tank 1 (S9).

If the detection signal I1 is in the state where the machining liquid level is detected, the controller 11 controls the control signals O3, O4,
O6 is output, the solenoid valves V3 and V4 are opened, the pump P is driven (S10), and the machining liquid supply device 9 is simultaneously driven (S11). As a result, the working fluid in the working tank 1 is supplied to the second pipeline B or the fourth branching from the second pipeline B.
It is re-supplied to the processing tank 1 through the pipe D of the above.

On the other hand, when the upper float switch 4 does not detect the machining liquid surface, it is detected that sufficient machining liquid is not stored in the machining tank 1, and a buzzer or a lamp is emitted to notify (S15). ), The machining liquid circulation switch is turned off (S1). At this time, if a float switch for detecting the lower limit is also installed in the machining fluid tank 2 so that it can be detected whether or not a predetermined machining fluid is present in the machining fluid tank 2, the machining fluid supply switch can be automatically operated. Enter processing fluid to enter processing tank 1
It is also possible to feed the solution to the substrate and start the circulation of the working fluid after the completion of the feeding.

When the machining is completed and the machining liquid circulation switch is turned off (S12), the control signals O3, O4, O are generated.
6 is output to close the solenoid valves V3 and V4 and stop the pump P (S13). At the same time, the control signal O7 is output to stop the machining fluid cooling device 9 (S
14). When another switch is pressed midway, the machining liquid circulation switch is turned off (S2) and the solenoid valve V
3, V4 is closed and the pump P is stopped (S3). Then, the solenoid valve and the pump are controlled based on the input of another pressed switch (S4).

When the machining fluid stored in the machining tank 1 is discharged, the machining fluid discharge switch of the operation switch device 12 is pressed (S3). And since the machining liquid supply switch and the machining liquid circulation switch are turned off,
When the machining fluid discharge switch is input (S16), the control device 11 causes the control signals O3, O5, O6 solenoid valves V3 and V5.
Is opened and the pump P is driven (S17). As a result, the working liquid in the working tank 1 is sent to the working liquid tank 2 through the third conduit C.

After that, when the lower float switch 5 installed at the lowermost part of the processing tank 1 no longer detects the machining liquid level and the detection signal I2 is not output (S18), the control device 11 causes the control signals O3 and O5. , O6 to close the solenoid valves V3 and V4 and stop the pump P (S19). Then, the machining liquid supply switch is turned off (S1). This prevents overflow of the working fluid and idling of the pump, and also prevents the working fluid from flowing back from the working fluid tank 2 to the working vessel 1.

The method of supplying and discharging the working fluid of the present invention will be described below in accordance with the working procedure. In order to perform processing, first, the workpiece 3 is placed in the processing tank 1 and then the processing tank 1 is placed in a liquid-tight state. Then, the solenoid valves V1 and V2 are opened by the control signal from the control device 11 and the pump P is driven to expedite the machining liquid stored in the machining tank 2 to the machining tank 1 via the pipe line A. At this time, the solenoid valve V1
Other than V2 and V2 are closed. When the upper float switch 4 detects the machining liquid level, the controller 11
Receives the detection signal, the pump P is stopped and the solenoid valves V1 and V2 are closed.

Subsequently, while the workpiece 3 is immersed in the machining liquid, a voltage for electric discharge machining is applied to the wire electrode and the workpiece 3, and the two are moved relative to each other to form a desired shape. Do. Detailed description of the electric power source device for electric discharge machining, the wire electrode feeding device, each relative movement device for relatively moving the wire electrode and the workpiece, and the method for controlling them will be omitted.

During machining, machining scraps are generated by machining, and the temperature of machining fluid rises due to machining, which deteriorates the machining environment. Therefore, the control device controls the solenoid valves V3 and V4.
And the pump P is driven to circulate the working liquid in the working tank 1 along the pipe B. During this period, the other control valves are closed. Therefore, the working fluid in the working tank 1 is forcibly discharged by the pump P, cooled to a predetermined temperature by the working fluid cooling device 9, and
It is purified by the filter device 6 and supplied again to the processing tank 1. Further, the working liquid is supplied from the branch point to the working gap from the working liquid jet nozzles 7 and 8 through the pipe D.

Further, the working liquid cooled by the working liquid cooling device 9 is supplied to the working gap along the pipe D as a working liquid jet. Then, in the above-described powder processing, the mixed fine powder gradually precipitates in the processing tank 1, and the substantially mixed concentration of the specific fine powder in the processing liquid decreases. Therefore, it is possible to stir the working fluid in the working tank 1 in the process of re-supplying the working fluid through the conduit B. Therefore, for example, the opening of the processing tank 1 of the pipeline B is tapered,
If the working fluid is discharged along the corners of the working tank 1 to generate a vortex in the working fluid in the working tank 1, the stirring effect can be further enhanced.

In the pipe B, for example, a filter device such as a ceramic filter device for removing fine powder having a specific particle size, a magnetic filter device for removing only metal powder, or the like is used as the filter device, or the filter device 6 is used. By applying the configuration of the embodiment, such as by adopting a pipeline structure that can be switched and used, it is possible to easily switch between powder processing and powder-free processing. The liquid circuit arrangement including the installation location and the number of the filter device and the working liquid cooling device in the pipeline B is as follows.
It can be appropriately designed according to the capability of each device, the purpose of processing, the processing liquid used, etc. without departing from the gist of the present invention.

Then, when it becomes necessary to discharge the machining liquid after one machining process or a series of machining is completed, the control device opens the solenoid valves V3 and V5 based on a command such as an input from an operation switch. At the same time, the pump P is driven to drain the machining liquid in the machining tank 1 into the machining liquid tank 2 via the pipe line C. Then, when the lower float switch 5 detects that the working fluid in the working tank 1 is discharged, the control device receives the detection signal and stops the pump P and closes the solenoid valves V3 and V5, and the working fluid tank. 2. Prevent backflow of the working fluid.

In this way, since the opening and the opening are shared in the processing tank 1 by the rapid delivery and the discharge of the processing liquid, a separate drain or overflow discharge chamber is not required. Furthermore, since the lower float switch 5 can detect the lower limit of the liquid level of the processing tank 1 and detect that the processing liquid does not remain in the processing tank 1,
The risk of an accident in which the processing liquid overflows from the processing tank 1 is extremely low.

When it is desired to remove the machining dust and fine powder mixed in the machining fluid at the next machining, the solenoid valve V1 and the solenoid valve V4 are opened without supplying the machining fluid through the conduit A,
By supplying the working liquid to the filter device 6 using the conduit A and the conduit B, the fine powder can be removed. Also,
When the processing tank 1 is washed, not only the pipeline A but also the pipeline A and the pipeline B can be used.

As described above, according to the configuration of this embodiment, the working fluid can be managed in the same manner as in the conventional case, but the working fluid to be used may be approximately the same volume as the working tank 1. Also,
In addition to providing flexibility in the installation position and specifications of the working fluid tank 2, it is possible to supply, circulate, stir and discharge the working fluid with one pump. When a water-based working fluid is used and the specific resistance value of the working fluid needs to be maintained within a predetermined range, a deionizer may be installed on the pipe line B.

FIG. 4 is a constitutional view showing another embodiment of the present invention, in which a working fluid supply device in a wire cut electric discharge machining apparatus for dipping an object to be machined using an oil-based machining fluid for electric discharge machining. Is an example of. The same reference numerals are used for the same devices and members as in FIG.

The pipe line A forms a first pipe line as shown in FIG. 5A, and basically two pipe lines are formed on the pipe line.
One solenoid valve V1 and V2, and one pump P capable of forward and reverse rotation are provided. The first pipeline is a machining fluid supply pipeline for supplying the machining fluid stored in the machining fluid tank 2 to the machining tank 1. Normally, when there is no machining fluid in the machining tank 1, It is used when the working fluid is expeditedly fed and the working fluid is quickly stored in the working tank 1 so that the workpiece 3 is immersed in the working fluid.

The conduit B forms a second conduit as shown in FIG. 5 (2), and basically 2 conduits are formed on the conduit.
There are provided one solenoid valve V3 and V4, one forward / reverse rotatable pump, and a filter device 6. This second pipeline is mainly for once discharging the used processing liquid that has become dirty in the processing tank 1 to the outside of the processing tank 1, purifying the dirty processing liquid that contains processing chips, and returning it to the processing tank 1 again. Used as a working fluid circulation line. In powder processing, it is used for stirring the processing tank 1.

The third pipe for discharging the working fluid in this embodiment is provided with the working fluid tank 2 as shown in FIG. 2C.
It is the same pipeline as the pipeline A supplied from the above to the processing tank 1. That is, by driving the pump P in the reverse direction, the first
The working fluid in the working tank 1 is discharged to the working fluid tank 2 by feeding the working fluid in the direction opposite to the feeding direction of the working fluid in the pipeline.

The pipe D forms a fourth pipe for the machining liquid jet branched from the second pipe as shown in FIG. 5B, and the machining liquid jet is formed on the pipe. A machining liquid jet adjusting device 10 including a throttle valve and a check valve for adjusting the strength of the machining fluid is provided. At this time, it goes without saying that a sensor for detecting the hydraulic pressure or the flow rate may be provided to automatically adjust the strength of the machining fluid jet.

FIG. 6 is a flow chart for explaining the operation of the control device 11 in this embodiment. When the control device 11 is turned on, a plurality of switches on the operation switch device 12, a machining liquid supply switch, a machining liquid circulation switch,
The machining fluid discharge switches are turned off (S
1). Further, all the solenoid valves V1 to V5 are closed, and the pump P is stopped, or the state is confirmed (S2).

When the workpiece is installed in the processing tank 1 and the processing liquid is supplied to the processing tank 1, the processing liquid supply switch of the operation switch device 12 is pressed (S3). When the supply switch is pressed (S4), the control device 11
Is a pump P that outputs control signals O1, O2, O5, opens the solenoid valves V1 and V2, and is capable of delivering liquid in both directions.
Are driven in the positive direction (S5). As a result, the working liquid in the working liquid tank 2 is sent to the working tank 1 through the first pipeline A. At this time, the plurality of switches are configured so as not to be in the state of being input at the same time, as in the apparatus of the previous embodiment.

After that, when the upper float switch 4 which is set to the required height in advance detects the machining liquid level and outputs the detection signal I1 (S6), the control device 11 responds to the signal I1 by controlling the control signal O1. Outputs O2 and O5, and the solenoid valve V
1 and V2 are closed and the pump P is stopped (S
7). Then, the machining liquid supply switch is turned off (S1).

Next, when machining is performed with the machining fluid stored in the machining tank 1, the machining fluid circulation switch of the operation switch 12 is pressed (S2). As described above, since the other switches are in the off state at this time, when this machining liquid circulation switch is input (S8), the control device 11
Input the detection signal I1 from the upper float switch 4,
It is detected whether the processing liquid is stored in the processing tank 1 (S9).

If the detection signal I1 is in the state where the machining liquid level is detected, the controller 11 controls the control signals O3, O4,
O5 is output, the solenoid valves V3 and V4 are opened, and the pump P is driven in the forward direction (S10). At the same time,
The control signal O6 is output to drive the machining fluid supply device 9 (S11). As a result, the processing liquid in the processing tank 1 is
Is re-supplied to the processing tank 1 through the pipeline B or the fourth pipeline D branched therefrom.

On the other hand, when the upper float switch 4 does not detect the machining liquid level, a lamp or the like is used to notify (S1
5), the machining liquid circulation switch is turned off (S1). At this time, the liquid can be automatically sent to circulate the working liquid, as in the case of the previous embodiment.

When the machining is completed and the machining liquid circulation switch is turned off (S12), the control signals O3, O4, O are generated.
5, O6 are output, the solenoid valves V3, V4 are closed, the pump P is stopped (S13), and at the same time, the working fluid cooling device 9 is stopped (S14). When another switch is pressed midway, the machining liquid circulation switch is turned off (S2), the solenoid valves V3 and V4 are closed, and the pump P is stopped (S3). Then, the solenoid valve and the pump are controlled based on the input of another pressed switch (S4).

When the machining fluid stored in the machining tank 1 is discharged, the machining fluid discharge switch of the operation switch device 12 is pressed (S3). When the machining fluid discharge switch is input (S16), the control device 11 causes the control signals O1, O4, O.
5 is output, the solenoid valves V1 and V2 are opened, and the pump P is driven in the opposite direction (S17). That is, the working fluid is sent in the opposite direction on the same pipeline as when the working fluid is rapidly sent, and the working fluid is returned from the working tank 1 to the working liquid tank 2.

After that, when the lower float switch 5 installed at the bottom of the processing tank 1 no longer detects the machining liquid level and the detection signal I2 is not output (S18), the control device 11 causes the control signals O1 and O2 to be output. , O5 are output to close the solenoid valves V3 and V4 and stop the pump P (S19). Then, the machining liquid supply switch is turned off (S1).

Among the above steps, the operations of step 7 and step 19 are achieved by closing all the electromagnetic valves in step 2 and stopping the pump, so that they are omitted from the control step. You can also

The processing liquid is expeditedly sent from the processing liquid tank 2 to the processing tank 1.
In order to fill the machining liquid, the electromagnetic valves V1 and V2 are opened and the pump P is driven in the forward direction, and the process is performed via the conduit A. At this time, all but the solenoid valves V1 and V2 are kept closed. When the upper float switch 4 detects the machining liquid level, the pump P is driven and the solenoid valves V1 and V2 are closed.

When the machining liquid in the machining tank 1 is circulated or the machining liquid in the machining tank 1 is agitated during machining, the solenoid valves V3 and V4 are opened and the pump P is turned on. Direction, and via line B. During this period, the other control valves are closed. Therefore, the working fluid in the working tank 1 is forcibly discharged by the pump P, cooled to a predetermined temperature by the working fluid cooling device 9, purified by the filter device 6, and supplied again to the working tank 1. The machining liquid jet can be supplied to the machining gap via the conduit D connecting the branch point set on the conduit B to the discharge port of the machining liquid supply nozzle.

When it is necessary to discharge the machining liquid from the machining tank 1 due to the end of machining or the like, the solenoid valves V1 and V2 are opened and the pump P is driven in the opposite direction to make the pipeline A
Via. When the lower float switch 5 of the processing tank 1 detects that the processing liquid in the processing tank 1 has been discharged, the electromagnetic valves V1 and V2 are closed and the pump P is stopped.

As described above, according to the configuration of the apparatus and method of this embodiment, the steps of rapid delivery and discharge of the working fluid can be performed in the same pipe line, and the configuration of the fluid circuit can be simplified, and the scale of the apparatus can be increased. Can be further reduced.

As described above, the structure of the present invention is generally the first.
The third to third pipelines are formed by a solenoid valve and a common pump to supply, circulate, stir, and discharge the working fluid. Various circuits and members can be arranged without departing from the spirit of the invention. Therefore, the arrangement and piping of each device can be arbitrarily set without departing from the spirit of the present invention, and the degree of freedom thereof is large. In addition, although the wire-cut electric discharge machine is described in the embodiment, it can be used for other electric machining apparatuses such as a die-sinking electric discharge machine and an electrolytic machine which immerse a workpiece in a machining fluid for machining. is there.

[0083]

[Effects] Since the apparatus of the present invention is configured as described above, firstly, during working such as circulating the working fluid, supplying a jet flow, stirring, etc., Since it is purified and re-supplied in the circulation instead of being returned to
The amount of the working liquid used can be made approximately the same as the amount stored in the working tank. Therefore, not only is it economical, but the working liquid tank can be made smaller, so that the installation area of the entire apparatus can be greatly reduced.

Secondly, by reducing the capacity of the working liquid tank, the working tank can be made compact, and the operability and maintenance performance are further improved. Further, if the lower part of the working liquid tank is formed in a funnel shape, the cleaning work of the working liquid tank can be simplified and the working efficiency can be further improved.

Thirdly, according to the construction in which the liquid level of the processing tank is detected and the control valve and the pump are operated in response to the supply, circulation, stirring, and discharge of the processing liquid, the discharge chamber for overflow is unnecessary. Therefore, more space saving can be achieved. In addition, since members such as a weir plate, which are required for the conventional configuration of the drain portion, are not required, the processing tank can be made simpler, and the operability is excellent and it is economically beneficial.

Fourthly, since the pump is forcibly draining the liquid, it is not necessary to discharge the working liquid through the drain as in the conventional case, so that the machining liquid can be processed in a shorter time. The liquid can be discharged and the work efficiency is improved. Further, according to this configuration, there is flexibility in the installation location of the processing liquid tank, for example, it can be installed either above or below the processing tank, and a more suitable arrangement of the apparatus becomes possible.

Fifth, since the processing liquid can be supplied, circulated, stirred and discharged by one pump,
The device configuration can be simplified.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a working fluid supply apparatus of the present invention.

FIG. 2 is a diagram showing first to fourth conduits in the apparatus of the embodiment shown in FIG.

3 is a flowchart showing an operation of a control device 11 in the device of FIG.

FIG. 4 is a configuration diagram showing another embodiment of the working fluid supply apparatus of the present invention.

5 is a view showing first to fourth conduits in the apparatus of the embodiment shown in FIG.

6 is a flowchart showing the operation of the control device 11 in the device of FIG.

FIG. 7 is a schematic configuration diagram showing an example of a machining fluid supply device in a conventional wire-cut electric discharge machining device.

[Explanation of symbols]

 1, machining tank 2, machining fluid tank 3, workpiece 4, upper float switch 5, lower float switch 6, filter device 7, upper machining fluid jet nozzle 8, lower jet nozzle 9, machining fluid cooling device 10, machining fluid Jet adjusting device 11, control device 12, operation switch device V, valve P, pump O, output signal I, input signal

Claims (14)

[Claims] 1. A machining fluid supply device of an electromachining apparatus configured to immerse a workpiece in a machining fluid to perform machining, wherein a machining tank and a machining fluid having substantially the same amount as the capacity of the machining tank are provided. A storable machining fluid tank, a first conduit for supplying the machining fluid from the machining fluid tank to the machining tank via the first valve and the second valve, a third valve and a fourth valve. A second conduit for circulating the working fluid in the working tank via a valve, a filter device provided in the second conduit, and the working tank via the third valve and the fifth valve. A machining fluid supply apparatus comprising: a third pipeline for discharging the machining fluid to the machining fluid tank; and a common pump provided in the first to third pipelines. 2. A machining fluid supply device of an electromachining apparatus configured to immerse a workpiece in a machining fluid to perform machining, wherein a machining tank and a machining fluid having substantially the same amount as the capacity of the machining tank are provided. A storable machining fluid tank, a first conduit for supplying the machining fluid from the machining fluid tank to the machining tank via the first valve and the second valve, a third valve and a fourth valve. A second pipe for circulating the working fluid in the working tank through a valve, a filter device provided in the second pipe, the second valve, and the first valve. A third pipe line for discharging the machining liquid from the machining tank to the machining liquid tank; and a common forward / reverse pump provided in the middle of the first to third pipe lines. Working fluid supply device. 3. A machining fluid supply device of an electromachining apparatus configured to immerse a workpiece in a machining fluid to perform machining, wherein a machining tank and a machining fluid having substantially the same amount as the capacity of the machining tank are provided. A storable working liquid tank, a first pipeline for supplying the working fluid from the working fluid tank to the working tank, and a second pipeline having a filter device for circulating or stirring the working fluid in the working tank. A third conduit for discharging the working liquid from the working tank to the working liquid tank, at least four control valves respectively provided in the first to third conduits, and the first to third Common pump provided in the pipeline, at least two liquid level detectors provided in the machining tank for detecting the upper limit and the lower limit of the machining liquid in the machining tank, respectively, and detection signals of the liquid level detector. A control device for controlling the control valve or the pump based on A machining fluid supply device. 4. In the second pipeline, a branch point is provided on the pipeline between the machining tank and a valve provided between the machining tank and the pump, and the branch point and the machining liquid jet flow. The machining fluid supply device according to claim 1, further comprising a fourth conduit that connects the discharge port. 5. The machining fluid supply device according to claim 4, further comprising a machining fluid flow rate adjusting device for adjusting the flow rate of the machining fluid jet in the fourth pipeline. 6. The machining fluid supply device according to claim 5, wherein the machining fluid flow rate adjusting device is a throttle valve. 7. The machining fluid supply device according to claim 5, wherein the machining fluid flow rate adjusting device is a constant flow valve. 8. The working fluid supply apparatus according to claim 4, further comprising a check valve for preventing backflow of the working fluid in the fourth pipeline. 9. A filter device is provided in the second pipeline on the pipeline between the machining tank and a valve provided between the machining tank and the pump. The machining fluid supply device according to claim 1. 10. The machining fluid supply device according to claim 9, wherein the filter device is a magnetic filter device. 11. The working fluid cooling device is provided on the pipeline between the machining tank and a valve provided between the machining tank and the pump in the second pipeline. The machining fluid supply device according to claim 1. 12. A machining fluid supply method for electromachining, wherein a workpiece is immersed in a machining fluid for machining, and at least an amount of the machining fluid capable of immersing the workpiece in the machining tank is used as the machining tank. The step of storing in a machining fluid tank having substantially the same amount of capacity, the valve provided in the middle of the first pipeline connecting the machining vessel and the machining fluid tank is released, and the pump is driven to drive the machining fluid tank. The step of supplying the working fluid of the above to the working tank to immerse the workpiece in the working fluid; the step of applying a predetermined voltage to the workpiece and the tool electrode to process the workpiece; During processing, the valve provided in the middle of the second pipe connecting one part of the processing tank to another part was opened, and the pump was driven to circulate the processing liquid in the processing tank to contaminate it. The step of purifying the processing liquid and the above processing tank And opening a valve provided in the middle of a third pipeline connecting the machining fluid tank and driving the pump to discharge the machining fluid from the machining fluid tank to the machining fluid tank. Characteristic machining liquid supply method. 13. A fourth conduit for branching the valve between the valve and the machining tank in the second conduit during the machining to connect the machining fluid jet discharge port with the workpiece and the tool electrode. The machining liquid supply method according to claim 12, further comprising a step of supplying a machining liquid jet to the gap. 14. A working liquid in the working tank is opened by opening a valve provided in the middle of a second pipeline connecting one location of the working tank and another location of the working tank during the working. 14. The method according to claim 12 or 13, further comprising the step of circulating the liquid to stir the processing liquid in the processing tank.
The method for supplying a working fluid according to item 1.