JPS604650Y2 - Jet machining fluid supply device for electrical discharge machining - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a jet machining fluid supply device for electrical discharge machining.

It is well known that a machining electrode and a workpiece are opposed to each other with a micromachining gap, and a machining fluid is jetted into the micromachining gap while current is applied between the machining electrode and the workpiece to process the workpiece.

However, if the workpiece has many complicated unevenness or curved parts, deep slits, holes with irregular bottoms, etc., or if it is necessary to perform machining of non-simple shapes, etc. If the gas accumulates or gets clogged, jumping the electrode up and down is not always sufficient to remove it. Therefore, an injection nozzle is installed in the machining gap from multiple directions at all times or when the electrode jumps, etc. As disclosed in Japanese Patent Publication No. 51-36516, one or more machining fluid spray nozzles are provided around the machining gap, and the nozzle is rotated or multiple nozzles are switched. There is a device that changes the jet direction of the machining fluid by sequentially switching the jet flow.

In this way, with conventional devices that switch the jet flow, the nozzle part where the jet flow is switched and the jet flow has stopped has to wait its turn until the next jet flow is applied, and during that time, the required jet flow is not produced. There was a drawback.

Cutting debris or chips generated during machining can cause arc discharge if the amount is too large, but the presence of an appropriate amount is necessary to trigger pulse discharge.

Therefore, in order to remove the excess chips and uniformly distribute the necessary amount of chips, it was found that it is best to jet out the machining fluid all at once and change the flow of the machining fluid.

To this end, the present invention injects machining fluid from multiple nozzles all at once, and sequentially reduces or closes the flow rate adjustment solenoid valves provided in each nozzle for a predetermined period of time. The purpose of this is to change the direction of flow of machining fluid and to control the flow rate.

Its structure is that a part of the system is equipped with a distribution tank, and the machining liquid is once supplied and stored in this distribution tank, and then discharged into a minute gap through multiple injection nozzles. Each of the solenoid valves is provided with a solenoid valve, and an electronic switch such as a transistor is used to control the excitation of each solenoid coil of the solenoid valve so that the nozzles injecting machining fluid of the solenoid valve decrease or stop the flow rate in a predetermined order. By changing the flow rate of the machining fluid during the overall jet flow and applying shock to the chip and gas due to changes in the flow rate,
The device efficiently removes chips and gas, and controls the switching of the solenoid valve using an electric circuit, thereby avoiding the intervention of a rotating mechanism such as an electric motor, thereby achieving a small size and reliable operation.

Next, an embodiment of the device of the present invention will be explained with reference to a sectional side view of the main parts shown in Fig. 1 and a wiring diagram of a control circuit for a solenoid valve shown in Figs. 2a and b. Distribution tank 2
will be established.

3a, 3b, and 3c are three injection nozzles, each with a steel ball 4a at its inlet.

Electromagnetic valve sections 4, 5.6 are provided, each of which includes excitation coils 5a, 6a and excitation coils 4b, 5b, 6b.

Regarding the excitation circuit of the excitation coils 4b, 5b, and 6b, the second
Figures a and b will be discussed later.

In addition, 7 is a machining fluid, 8 is an attraction magnet having an attraction coil 8a, 9 is a vibration magnet and has a vibration coil 9a, and 10 is an excitation device for the vibration coil 9a.

Also, both a and b in Fig. 2 are excited, and 4b, 5b, 6b
These excitation circuits all use transistors as electronic switches. In the case of Figure 2a, when switch S is turned on, capacitor C is first charged with the voltage of power supply E, and
When the base voltage of the transistor Tr2 reaches the specified base voltage, the transistor Tr2 is turned on and a current is passed through the coil 5b to attract the steel ball 5a shown in FIG. 1 and close the inlet of the injection nozzle 3b.

In this state, the capacitor C3 is charged, the transistor Tr1 is turned on, the coil 4b is excited, the steel ball 4a is attracted, the inlet of the nozzle 3a is closed, and the mouth of the nozzle 3b is opened.

Similarly, by charging the capacitor C2, the transistor T
When r3 is turned on, the coil 6b is energized, attracts the steel ball 6a, closes the inlet of the nozzle 3C, opens the inlet of the nozzle 3a, and as long as the switch is on, 1 of 4b, 5b, 6b
They are energized in turn.

The same is true for FIG. Tr5. Apply an operating voltage to the Tr 6, turn on one of them in turn, and excite the coils 4b, 5b, and 6b, respectively, to attract the steel balls 4a, 5aw, and 6a, and sequentially block one of the injection nozzles 3av, 3bt, and 3c. do.

Next, the operation of the device of the present invention will be explained. First, the supply device 1 is placed on the iron outer casing or machining table of a desired electric discharge machining device or its peripheral equipment, and then the switch is turned on. The attraction magnet 8 is magnetized and the outer casing or Fix it to the processing table by suction.

On the other hand, a pump pumps the machining liquid through the liquid inlet of the supply device 1 to the distribution tank 2.

Further, the oscillation circuit 10 is operated to excite the vibration magnet 9 and apply ultrasonic vibration to the distribution tank 2.

In this way, if the excitation circuit of the regulating valve part 4.5.6 of each injection nozzle 3a, 3b, 3c is operated, the injection nozzles 3a, 3b, 3c will reduce or stop the jet flow in turn, so that injection can be performed sequentially. There is no longer a situation where the machining fluid is not sprayed until it is the turn to spray the machining fluid, which occurs when the machining fluid is sprayed. By applying an impact to the machining debris and gas, the overall direction and strength of the jet flow changes while circulating, and the machining liquid is selectively forced and sprayed to areas where machining debris, gas, etc. are likely to accumulate in the gaps. can be efficiently eliminated by

Therefore, processing performance can be significantly improved.

Moreover, in the device of the present invention, the switching and adjustment of the jet flow from the injection nozzle is performed using an electric circuit using an electronic switch such as a transistor, so a rotating mechanism such as a motor is not required, and the device is small, lightweight, and reliable in operation.

Although there are three injection nozzles in the figure, there may be many injection nozzles, and there is no need to limit the order in which the injection nozzles are closed, and the valve portion 4.5.6 may use a flow rate regulating valve. ,
Of course, in order to achieve the above-mentioned objects and effects of the present invention, the nozzle injection liquid flow rate may be reduced to a certain degree or more when each valve is operated.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of an embodiment of the device of the present invention, Fig. 2a
, b is a wiring diagram of the electronic excitation circuit of the regulating valve section. 1... Jet machining liquid supply device, 2... Distribution tank, 3a, 3b, 3c... Injection nozzle, 4, 5, 6... Adjustment valve Part, 7...
Processing fluid.

Claims (1)

[Scope of utility model registration request] In a device that uses multiple machining fluid injection nozzles to supply jet machining fluid around the electrical discharge machining gap, each of the multiple machining fluid jet nozzles has a solenoid valve for adjusting the flow rate at the inlet to each nozzle. Each of the solenoid valves is adjusted and set to a normally open state, and is provided with a solenoid valve excitation control device that sequentially reduces or closes the opening degree of each solenoid valve in a predetermined order and for a predetermined period of time. Jet machining fluid supply device for machining.