Electrical discharge machine of which axis feeding properties are changeable

Patent metadata

Field	Value
Publication number	US-2016288231-A1
Application number	US-201615083556-A
Country	US
Kind code	A1
Filing date	Mar 29, 2016
Priority date	Mar 30, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

The upper limit value for the axis feeding speed is set to the maximum speed that can secure the safety in a wire electrical discharge machine. In the case where the level of the process liquid is higher than a predetermined height, however, the upper limit value is made smaller. In order to prevent the process liquid from spilling to the outside of the process tank, the acceleration or the jerk may be changed instead of the axis feeding speed. In the case where the process liquid level is high, it is difficult for the process liquid to spill when the speed is adjusted slowly. In addition, the time constant may be increased or the instruction for speed may be changed from the linear type to the S shape type.

First claim

1 . An electrical discharge machine for processing a work that is immersed in a process liquid, comprising:
a process tank for storing a process liquid into which a work is to be immersed; a liquid level information acquiring unit for acquiring information that becomes an index of the level of the process liquid; and an axis feeding property changing unit for changing the axis feeding properties in accordance with the information acquired by said liquid level information acquiring unit.

2 . The electrical discharge machine according to claim 1 , wherein information for the index of said process liquid level includes at least one of the process liquid level detected by a liquid level detection unit;
the coordinate value along the Z axis of an electrode or a guide for guiding an electrode; the set value for the process liquid level; the set value for the thickness of the work; the instruction for supplying the process liquid; the instruction for discharging the process liquid; the open or closed state of the door; or the load of the motor for driving the axis.

3 . The electrical discharge machine according to claim 1 , wherein said axis feeding property changing unit changes at least one of the axis feeding speed;
the axis feeding acceleration; the axis feeding jerk; the axis feeding adjustable speed time constant; or the type of the axis feeding adjustable speed.

4 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the process liquid level detected by a liquid detection unit, and in the case where the process liquid level is higher than a predetermined liquid level, as opposed to the case where the process liquid level is lower than the predetermined liquid level, said axis feeding property changing unit performs at least one of: reducing the absolute value of the axis feeding speed, reducing the absolute value of the axis feeding acceleration, reducing the absolute value of the axis feeding jerk, increasing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

5 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the coordinate value along the Z axis, and in the case where the coordinate value along the Z axis is higher than a predetermined height, as opposed to the case where the coordinate value along the Z axis is lower than the predetermined height, said axis feeding property changing unit performs at least one of: reducing the absolute value of the axis feeding speed, reducing the absolute value of the axis feeding acceleration, reducing the absolute value of the axis feeding jerk, increasing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

6 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the set value for the process liquid level, and in the case where the set value for the process liquid level is greater than a predetermined value, as opposed to the case where the set value for the process liquid level is smaller than the predetermined value, said axis feeding property changing unit performs at least one of: reducing the absolute value of the axis feeding speed, reducing the absolute value of the axis feeding acceleration, reducing the absolute value of the axis feeding jerk, increasing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

7 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the set value for the thickness of the work, and in the case where the set value for the thickness of the work is greater than a predetermined value, as opposed to the case where the set value for the thickness of the work is smaller than the predetermined value, said axis feeding property changing unit performs at least one of: reducing the absolute value of the axis feeding speed, reducing the absolute value of the axis feeding acceleration, reducing the absolute value of the axis feeding jerk, increasing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

8 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the instruction for supplying the process liquid to the process tank, and after the liquid supplying instruction, as opposed to before the liquid supplying instruction, said axis feeding property changing unit performs at least one of: reducing the absolute value of the axis feeding speed, reducing the absolute value of the axis feeding acceleration, reducing the absolute value of the axis feeding jerk, increasing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

9 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the instruction for discharging the process liquid from the process tank, and after the liquid discharging instruction, as opposed to before the liquid discharging instruction, said axis feeding property changing unit performs at least one of: increasing the absolute value of the axis feeding speed, increasing the absolute value of the axis feeding acceleration, increasing the absolute value of the axis feeding jerk, reducing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

10 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the open or closed state of the door, and when the door is in the open state, as opposed to when the door is in the closed state, said axis feeding property changing unit performs at least one of: increasing the absolute value of the axis feeding speed, increasing the absolute value of the axis feeding acceleration, increasing the absolute value of the axis feeding jerk, reducing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

11 . The electrical discharge machine according to claim 1 , wherein
the index of said process liquid level is the load of the motor for driving the axis, and when the load of the motor is greater than a predetermined value, as opposed to when the load of the motor is smaller than the predetermined value, said axis feeding property changing unit performs at least one of: reducing the absolute value of the axis feeding speed, reducing the absolute value of the axis feeding acceleration, reducing the absolute value of the axis feeding jerk, increasing the axis feeding adjustable speed time constant, or changing the type of the axis feeding adjustable speed.

Assignees

• Fanuc Corp

Inventors

• Nakashima Yasuo
• Kawahara Akiyoshi

Classifications

• B23H7/02 Primary

  Wire-cutting · CPC title

• G05B19/402

  characterised by control arrangements for positioning, e.g. centring a tool relative to a hole in the workpiece, additional detection means to correct position (G05B19/19 takes precedence) · CPC title

• B23H1/10

  Supply or regeneration of working media · CPC title

• B23H1/02 Primary

  Electric circuits specially adapted therefor, e.g. power supply, control, preventing short circuits or other abnormal discharges · CPC title

• B23H7/26

  Apparatus for moving or positioning electrode relatively to workpiece; Mounting of electrode · CPC title