JPH0150559B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a water jet machining method and apparatus for injecting ultra-high pressure water onto a workpiece from a nozzle and performing machining using the pressure of the ultra-high pressure water. be.

[Prior art]

Conventionally, ultra-high pressure water is injected from a nozzle, and the pressure of the ultra-high pressure water is used to process workpieces, such as LSI.
When deburring resin packages, cutting non-metallic materials such as printed wiring boards, etc., the nozzle is moved to the robot arm according to the uneven shape or gentle curved shape of the workpiece. Variable control is performed using an actuator such as, and tracing control is performed so that the distance between this nozzle and the workpiece is constant.

[Problem that the invention seeks to solve]

This conventional variable nozzle control type waterjet machining system is a nozzle mechanical follow-up control system using an actuator, and therefore has the disadvantage that the response of the nozzle to changes in the surface shape of the workpiece tends to be delayed. For this reason, it may not be possible to apply appropriate machining pressure to changes in the surface shape of the workpiece, and in the case of cutting, there is a risk that uniform machining may not be possible on the uneven surface of the workpiece. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a water jet processing method and apparatus that are excellent in responsiveness to changes in the surface shape of a workpiece.

[Means for solving problems]

The present invention is a water jet machining method in which ultra-high pressure water is injected from a nozzle 31 onto a workpiece 33 and machining is performed using the pressure of the ultra-high pressure water. ,
This is a water jet machining method in which the machining pressure on the surface of the workpiece 33 is controlled to be constant by variably controlling the ejection pressure from the nozzle 31 according to this distance.

The present invention also provides an ultra-high-pressure water generator 11, a nozzle 31 for injecting ultra-high-pressure water supplied from the ultra-high-pressure water generator 11 onto a workpiece 33, and a space between the nozzle 31 and the workpiece 33. The workpiece 33 is automatically adjusted according to the detection signal of the sensor 34 and variably controls the operating pressure in the ultra-high pressure water generator 11.
This is a water jet machining device equipped with a pressure control valve 15 that controls the machining pressure at a constant level on the surface of the water jet.

[Effect]

In the present invention, when the ultra-high pressure water supplied from the ultra-high pressure water generator 11 is injected from the nozzle 31 to the workpiece 33, the distance between the nozzle 31 and the workpiece 33 is detected by the sensor 34, and the distance between the nozzle 31 and the workpiece 33 is detected. The pressure control valve 15 in the ultra-high pressure water generator 11 is automatically adjusted in accordance with the detection signal of the sensor 34, and the operating pressure in the ultra-high pressure water generator 11 is variably controlled.

For example, if the distance between the nozzle 31 and the workpiece 33 changes to become larger,
By increasing the operating pressure, the ejection pressure at the nozzle 31 is increased, and the processing pressure applied to the surface of the workpiece 33 is automatically controlled to be kept constant.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the drawings.

Reference numeral 11 denotes an ultra-high-pressure water generator, and this ultra-high-pressure water generator 11 mainly includes a hydraulic power source 12 and an electromagnetically actuated 4-port 2-position switching type that controls the supply and discharge direction of the hydraulic pressure supplied from the hydraulic power source 12. a directional control valve 13, a double-rod type booster cylinder 14 driven by hydraulic pressure supplied and discharged by the directional control valve 13, and a proportional pressure control valve 1 that controls the operating pressure supplied to the booster cylinder 14.
5.

The booster cylinder 14 causes the directional control valve 13 to alternately apply hydraulic pressure to both sides of the piston 21, which has a large pressure receiving area, to forcefully move the plungers 22 provided on both sides of the piston 21 back and forth, thereby removing water from the water supply pipe 23. Water is sucked into the plunger chamber 25 on one side through the check valve 24, and from the plunger chamber 25 on the other side through the check valve 26 at a rate of 1000 to 4000 Kg/cm ^{2 .}
This is to discharge and supply ultra-high pressure water to the pipe line 27.

The pulsations occurring inside the pipe line 27 are smoothed out by an accumulator 28 provided in the pipe line 27.

The pipe line 27 is communicatively connected to the nozzle 31 .
This nozzle 31 is supported by a robot arm 32 or the like, and has its tip facing a workpiece 33.
Ultra-high pressure water is injected onto this workpiece 33.

Further, the nozzle 31 is integrally provided with a sensor 34 that detects the distance between the nozzle 31 and the workpiece 33 by a photoelectric method, a magnetic method, or the like without contact.

Furthermore, the output cord 40 of the sensor 34 is connected to the input terminal of a comparison circuit 41. This comparison circuit 41 electrically compares the set value inputted in advance to this comparison circuit 41 and the measured value detected by the sensor 34 and outputs the error. The terminal is connected to the input terminal of an amplifier 42, and the output terminal of this amplifier 42 is connected to the set pressure adjustment section 43 of the proportional pressure control valve 15.

The proportional pressure control valve 15 is a servo valve that adjusts the amount of oil drained into the tank from the hydraulic pressure source 12 to maintain the hydraulic pressure supplied to the booster cylinder 14 at a set pressure. The pressure is automatically variably adjusted in proportion to the output of the amplifier 42 (input to the set pressure adjustment section 43), and the hydraulic pressure supplied to the booster cylinder 14 is controlled proportionally.

Next, the operation of this embodiment will be explained.

The ultra-high pressure water discharged from the ultra-high pressure water generator 11 is supplied to the nozzle 31 through the pipe 27, and is sprayed from the nozzle 31 onto the workpiece 33 to deburr the LSI resin package as the workpiece. Or cutting, machining, etc. of non-metallic materials such as printed wiring boards.

In that case, the distance between the nozzle 31 and the workpiece 33 is detected by the sensor 34.
The measured value detected by is compared with the set value of the comparison circuit 41, and if there is an error, the error is amplified by the amplifier 42 and output to the set pressure adjustment section 43 of the proportional pressure control valve 15. Automatically and variably adjusts the set pressure.

As a result, the hydraulic pressure supplied to the booster cylinder 14 is adjusted, the water pressure generated in the pipe line 27 is adjusted, and the ejection pressure in the nozzle 31 is variably adjusted.

For example, when the distance between the nozzle 31 and the workpiece 33 changes to become larger, the proportional pressure control valve 15 automatically adjusts the pressure in response to the change in the distance to reduce the amount of pressure supplied to the booster cylinder 14. The hydraulic pressure is increased, and the plunger chamber 2
The generated water pressure discharged from 5 to the pipe line 27 is increased, and the ejection pressure at the nozzle 31 is increased by the increase in the separation distance. As a result, the processing pressure of the water jet applied to the surface of the workpiece 33 is automatically controlled to be kept constant.

Note that the robot arm 32 is not necessarily required, and the nozzle 31 may be fixedly installed.

Further, the present invention may be used in combination with a tracing control method in which the robot arm 32 keeps the nozzle 31 at a constant distance from the surface of the workpiece 33 to follow changes in the surface shape.
In that case, the present invention compensates for the shortcomings in responsiveness inherent in mechanical tracing control systems.

〔Effect of the invention〕

According to the present invention, the jetting pressure at the nozzle is variably controlled depending on the distance between the nozzle and the workpiece, so that the machining pressure on the surface of the workpiece is controlled at a constant level. There is no need for variable mechanical control of the nozzle, and the response to changes in the surface shape of the workpiece is fast. Therefore, it is possible to always apply appropriate machining pressure to changes in the surface shape of the workpiece.
In the case of cutting, the uneven surface of the workpiece can be processed uniformly.

Further, according to the present invention, the pressure control valve is automatically adjusted according to the detection signal of the sensor that detects the distance, and the operating pressure of the ultra-high pressure water generator is variably controlled so that the processing pressure is constant. Therefore, the ejection pressure can be continuously and highly accurately variably controlled using the pressure control valve.

[Brief explanation of drawings]

The figure is a fluid circuit diagram showing an embodiment of the water jet processing method and apparatus of the present invention. 11... Ultra-high pressure water generator, 25... Pressure control valve, 31... Nozzle, 33... Workpiece, 34...
...Sensor.

Claims (1)

[Claims] 1. In a water jet machining method in which ultra-high pressure water is injected from a nozzle onto a workpiece and machining is performed using the pressure of the ultra-high pressure water, the distance between the nozzle and the workpiece is detected, By variably controlling the ejection pressure in the nozzle according to this distance,
A water jet machining method characterized by controlling the machining pressure on the surface of a workpiece to a constant level. 2. An ultra-high-pressure water generator, a nozzle that injects ultra-high-pressure water supplied from the ultra-high-pressure water generator onto a workpiece, a sensor that detects the distance between the nozzle and the workpiece, and this sensor. and a pressure control valve that is automatically adjusted in response to a detection signal and variably controls the working pressure in the ultra-high pressure water generator to keep the processing pressure on the surface of the workpiece constant. Water jet processing equipment.