Electrical discharge machine and failure determining method

Patent metadata

Field	Value
Publication number	US-10549368-B2
Application number	US-201715649574-A
Country	US
Kind code	B2
Filing date	Jul 13, 2017
Priority date	Jul 14, 2016
Publication date	Feb 4, 2020
Grant date	Feb 4, 2020

Abstract

An electrical discharge machine includes: a machining power supply having a plurality of different circuit states, and configured to be capable of being set to one circuit state of the plurality of circuit states by switching at least one of electrical connection and electrical setting; a state determining unit configured to, when each of the plurality of circuit states is set as the circuit state of the machining power supply, determine whether or not the set circuit state is normal; a failure portion specifying unit configured to specify a failure portion of the machining power supply based on a determination result with respect to each of the plurality of circuit states obtained by the state determining unit; and a reporting unit (a display unit or the like) configured to report the failure portion specified by the failure portion specifying unit to an operator.

First claim

What is claimed is:

1. An electrical discharge machine configured to perform electrical discharge machining by applying a voltage to an inter-electrode gap formed between an electrode and a target workpiece and causing a current to flow, the electrical discharge machine comprising:
a machining power supply having a plurality of different circuit states, and configured to be set to one circuit state of the plurality of circuit states by switching at least one of an electrical connection or an electrical setting;
a control unit comprising a storage medium in which a program is stored and a processor, wherein the processor is configured to:
determine whether or not the set circuit state is normal in response to setting each of the plurality of circuit states as the circuit state of the machining power supply;
specify a failure portion of the machining power supply based on a determination result with respect to each of the plurality of circuit states; and
set each of the plurality of circuit states as the circuit state of the machining power supply sequentially by switching at least one of the electrical connection or the electrical setting; and

a display configured to report the failure portion specified by the processor to an operator,
wherein the processor is further configured to determine, in response to switching the circuit state of the machining power supply, whether or not the switched circuit state is normal.

2. The electrical discharge machine according to claim 1 , wherein the display is further configured to report the switching operation to the operator in response to switching the circuit state set to the machining power supply and in response to the operator's needs to perform a switching operation.

3. The electrical discharge machine according to claim 2 , further comprising a circuit configured to detect an inter-electrode voltage applied to the inter-electrode gap,
wherein the processor is configured to determine, in response to setting each of the plurality of circuit states as the circuit state of the machining power supply, whether or not the circuit state is normal based on the inter-electrode voltage detected by the circuit.

4. The electrical discharge machine according to claim 3 , wherein the processor is further configured to determine that the circuit state is abnormal in response to a determination that the inter-electrode voltage detected by the circuit is not in a predetermined range in advance in accordance with the set circuit state of the machining power supply.

5. The electrical discharge machine according to claim 1 , further comprising
a table configured to store the failure portion and abnormality patterns of the plurality of circuit states associated with the failure portion,
wherein processor is configured to specify the failure portion by comparing the abnormality patterns stored in the table and the determination result with respect to each of the plurality of circuit states.

6. The electrical discharge machine according to claim 1 , wherein the processor is configured to determine whether or not the switched circuit state is normal, based on a combination pattern of the determination result with respect to the plurality of circuit states set by sequentially switching at least one of the electrical connection or the electrical setting.

7. A failure determining method of an electrical discharge machine comprising a machining power supply having a plurality of different circuit states, and configured to be capable of being set to one circuit state of the plurality of circuit states by switching at least one of electrical connection and electrical setting, and the machine configured to perform electrical discharge machining by applying a voltage to an inter-electrode gap formed between an electrode and a target workpiece and to cause a current to flow, the failure determining method comprising:
a state determining step of, when each of the plurality of circuit states is set as the circuit state of the machining power supply, determining whether or not the set circuit state is normal;
a failure portion specifying step of specifying a failure portion of the machining power supply based on a determination result with respect to each of the plurality of circuit states provided in the state determining step;
a reporting step of reporting the failure portion specified in the failure portion specifying step to an operator; and
a setting switching step of setting each of the plurality of circuit states as the circuit state of the machining power supply sequentially by switching at least one of the electrical connection and the electrical setting,
wherein, in the state determining step, when the circuit state of the machining power supply is switched, whether or not the switched circuit state is normal is determined.

8. The failure determining method according to claim 7 , wherein, in the reporting step, when the circuit state set to the machining power supply is switched in the setting switching step and when the operator needs to perform a switching operation, the switching operation is reported to the operator.

9. The failure determining method according to claim 7 , further comprising a voltage detecting step of detecting an inter-electrode voltage applied to the inter-electrode gap,
wherein, in the state determining step, when each of the plurality of circuit states is set as the circuit state of the machining power supply, whether or not the circuit state is normal is determined based on the inter-electrode voltage detected in the voltage detecting step.

10. The failure determining method according to claim 9 , wherein, in the state determining step, when the inter-electrode voltage detected in the voltage detecting step is not in a predetermined range in advance in accordance with the set circuit state of the machining power supply, it is determined that the circuit state is abnormal.

11. The failure determining method according to claim 7 , further comprising a storing step of storing, as a table, the failure portion and abnormality patterns of the plurality of circuit states associated with the failure portion,
herein, in the failure portion specifying step, the failure portion is specified by comparing the abnormality patterns stored in the table and the determination result with respect to each of the plurality of circuit states provided in the state determining step.

Assignees

• Fanuc Corp

Inventors

• Nakashima Yasuo

Classifications

• B23H1/02 Primary

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

• G05B23/0218

  characterised by the fault detection method dealing with either existing or incipient faults · CPC title

• B23H11/00

  Auxiliary apparatus or details, not otherwise provided for · CPC title

• B23H7/14 Primary

  Electric circuits specially adapted therefor, e.g. power supply {(B23H3/02 takes precedence)} · CPC title

• B23H7/20

  for program control, e.g. adaptive · CPC title