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CN-122003306-A - Electric discharge machine and electric discharge machining method

CN122003306ACN 122003306 ACN122003306 ACN 122003306ACN-122003306-A

Abstract

The electric discharge machining device (1A) is provided with a power supply device (20) for supplying electric power between a tool electrode (4) and a workpiece (3), a current detection unit (9) for detecting an inter-electrode current value, which is the current value of the current flowing from the power supply device to the machining inter-electrode, a voltage command detection unit (12) for detecting an applied voltage value, which is the command value of the voltage applied to the machining inter-electrode, and an operation device (10A) for acquiring the inter-electrode current value and the applied voltage value, using a learning model for estimating the electrical characteristics inherent to the device from the inter-electrode current value and the applied voltage value, estimating the electrical characteristics from the inter-electrode current value and the applied voltage value, and determining a correction value for correcting the inter-electrode current value and the applied voltage value so that the estimated electrical characteristics become reference electrical characteristics, which are reference characteristics.

Inventors

  • KOYAMA KEIJI
  • MUTOH DAISUKE

Assignees

  • 三菱电机株式会社

Dates

Publication Date
20260508
Application Date
20231205

Claims (11)

  1. 1. An electric discharge machine, comprising: A power supply device for supplying electric power between the tool electrode and the machining gap between the workpiece and the tool electrode; A current detection unit that detects an inter-electrode current value, which is a current value of a current flowing from the power supply device to the machining inter-electrode; a voltage command detection unit for detecting an applied voltage value, which is a command value of a voltage applied across the machining poles, and And a computing device that obtains the inter-electrode current value and the applied voltage value, and determines a reference characteristic, which is an electrical characteristic in which the electrical characteristic estimated to be a reference, by using a learning model for estimating the electrical characteristic inherent to the device from the inter-electrode current value and the applied voltage value and estimating the electrical characteristic from the inter-electrode current value and the applied voltage value, and correcting the inter-electrode current value and the applied voltage value.
  2. 2. The electric discharge machining apparatus according to claim 1, wherein, The electrical characteristics include an impedance of a machining circuit including the power supply device and the machining gap, and a parasitic capacitance value between the machining gaps, The learning model includes an impedance learning model for inferring the impedance and a parasitic capacitance learning model for inferring the parasitic capacitance value, The computing device estimates the impedance from the inter-electrode current value using the impedance learning model, calculates an amount of electric power flowing between the machining electrodes from the inter-electrode current value, estimates the parasitic capacitance value from the amount of electric power and the applied voltage value using the parasitic capacitance learning model, and determines the correction value such that the estimated impedance and parasitic capacitance value become a reference impedance and a reference parasitic capacitance value.
  3. 3. An electrical discharge machining apparatus according to claim 1 or 2 wherein, The arithmetic device acquires learning data including the inter-electrode current value, the applied voltage value, and the electrical characteristic, and generates the learning model using the learning data.
  4. 4. An electric discharge machine, comprising: A power supply device for supplying electric power between the tool electrode and the machining gap between the workpiece and the tool electrode; A current detection unit that detects an inter-electrode current value, which is a current value of a current flowing from the power supply device to the machining inter-electrode; a voltage detection unit for detecting an applied voltage value, which is a voltage value of a voltage applied across the machining poles, and And an arithmetic device that estimates an electrical characteristic inherent to the device based on an inter-electrode current value and an applied voltage value in a case where the machining inter-electrode is in a separated state, a1 st circuit equation including the 1 st machining circuit including the power supply device and the machining inter-electrode in the separated state, an inter-electrode current value and an applied voltage value in a case where the machining inter-electrode is in a short-circuit state, and a2 nd circuit equation including the power supply device and the machining inter-electrode in the short-circuit state, and determines a correction value for correcting the inter-electrode current value and the applied voltage value so that the estimated electrical characteristic becomes a reference characteristic, that is, a reference characteristic.
  5. 5. The electric discharge machining apparatus according to claim 4, wherein, The inherent electrical characteristics of the device are the parasitic capacitance between the machining poles and the parasitic inductance on the machining circuit, The arithmetic device calculates the 1 st frequency characteristic which is the frequency characteristic of the 1 st processing circuit, compares the 1 st frequency characteristic which is the frequency characteristic of the 1 st circuit equation with the 1 st frequency characteristic, thereby estimating the parasitic capacitance value between the processing electrodes, The arithmetic device calculates the 3 rd frequency characteristic which is the frequency characteristic of the 2 nd processing circuit, compares the 4 th frequency characteristic which is the frequency characteristic of the 2 nd circuit equation with the 3 rd frequency characteristic, thereby estimating the parasitic inductance on the processing circuit, The arithmetic device determines the correction value such that the parasitic capacitance value and the parasitic inductance become the reference characteristic.
  6. 6. The electric discharge machine according to claim 5, wherein, The 1 st frequency characteristic is a frequency characteristic of an impedance of the 1 st processing circuit and a frequency characteristic of a phase delay between an inter-electrode current value and an applied voltage value of the 1 st processing circuit, The 2 nd frequency characteristic is a frequency characteristic of the impedance in the 1 st circuit equation and a frequency characteristic of the phase delay in the 1 st circuit equation, The 3 rd frequency characteristic is a frequency characteristic of the impedance of the 2 nd processing circuit and a frequency characteristic of the phase delay of the 2 nd processing circuit, The 4 th frequency characteristic is a frequency characteristic of the impedance in the 2 nd circuit equation and a frequency characteristic of the phase delay in the 2 nd circuit equation.
  7. 7. The electric discharge machining apparatus according to claim 6, wherein, The computing device calculates the 1 st frequency characteristic from the inter-electrode current value and the applied voltage value in the separated state, and calculates the 3 rd frequency characteristic from the inter-electrode current value and the applied voltage value in the short-circuit state.
  8. 8. The electric discharge machining apparatus according to any one of claims 1 to 7, characterized in that, The arithmetic device causes a display connected to the arithmetic device to display a button for correcting a deviation of the electric characteristic from the reference characteristic and a character indicating a correction content of the electric characteristic.
  9. 9. The electric discharge machining apparatus according to claim 8, wherein, The arithmetic device causes the display to display a character indicating that correction of the deviation of the electrical characteristic from the reference characteristic is completed and a character indicating how much deviation is present between the electrical characteristic and the reference characteristic.
  10. 10. An electric discharge machining method comprising the steps of: a power supply step of supplying power to a machining gap between a tool electrode and a workpiece by a power supply device provided in the electric discharge machining apparatus; a current detection step of detecting an inter-electrode current value, which is a current value of a current flowing from the power supply device to the machining inter-electrode; a voltage command detection step of detecting a command value, i.e., an applied voltage value, of a voltage value of a voltage applied across the machining poles, by the electric discharge machining device, and And a calculation step of obtaining the inter-electrode current value and the applied voltage value by the electric discharge machining apparatus, and determining a reference characteristic, which is an electrical characteristic in which the electric characteristic estimated by the electric discharge machining apparatus is a reference, by estimating the electrical characteristic from the inter-electrode current value and the applied voltage value using a learning model for estimating the electrical characteristic inherent to the electric discharge machining apparatus from the inter-electrode current value and the applied voltage value, and correcting the inter-electrode current value and the applied voltage value.
  11. 11. An electric discharge machining method comprising the steps of: a power supply step of supplying power to a machining gap between a tool electrode and a workpiece by a power supply device provided in the electric discharge machining apparatus; a current detection step of detecting an inter-electrode current value, which is a current value of a current flowing from the power supply device to the machining inter-electrode; A voltage detection step of detecting an applied voltage value, which is a voltage value of a voltage applied across the machining poles, by the electric discharge machining apparatus, and And a calculation step of estimating an electrical characteristic inherent to the electric discharge machining apparatus based on an inter-electrode current value and an applied voltage value in a case where the machining inter-electrode is in a separated state, a 1 st circuit equation including a 1 st machining circuit including the power supply apparatus and the machining inter-electrode in a separated state, an inter-electrode current value and an applied voltage value in a case where the machining inter-electrode is in a short-circuit state, and a2 nd circuit equation including a2 nd machining circuit including the power supply apparatus and the machining inter-electrode in a short-circuit state, and determining a correction value for correcting the inter-electrode current value and the applied voltage value so that the estimated electrical characteristic becomes a reference electrical characteristic, that is, a reference characteristic.

Description

Electric discharge machine and electric discharge machining method Technical Field The present invention relates to an electric discharge machine and an electric discharge machining method for machining a workpiece by discharging energy. Background In an electric discharge machining apparatus that performs machining of a workpiece by discharging energy while generating electric discharge between a machining electrode formed by a tool electrode and the workpiece, it is desirable to realize stable machining corresponding to the electric discharge machining apparatus. The machining condition adjustment device described in patent document 1 learns an adjustment action of a machining condition (such as a voltage waveform and a current waveform) corresponding to a machining state (such as a machining voltage, a machining current, and a machining speed), and predicts the adjustment action of the machining condition based on the machining state when a predetermined machining is performed. Patent document 1 International publication No. 2022/210472 Disclosure of Invention However, in the technique of patent document 1, since the adjustment actions common to a plurality of electric discharge machining apparatuses are learned, there is a problem that machining errors due to the electrical characteristics inherent to the electric discharge machining apparatuses cannot be corrected, and the machining quality is lowered. The present invention has been made in view of the above circumstances, and an object thereof is to provide an electric discharge machine capable of suppressing a reduction in machining quality. In order to solve the above problems and achieve the object, the electric discharge machining apparatus of the present invention includes a power supply device that supplies electric power to a machining gap between a tool electrode and a workpiece, a current detection unit that detects a gap current value that is a current value of a current flowing from the power supply device to the machining gap, a voltage command detection unit that detects an applied voltage value that is a command value of a voltage applied to the machining gap, and an arithmetic device that obtains the gap current value and the applied voltage value, and determines a correction value for correcting the gap current value and the applied voltage value so that the estimated electric characteristic becomes a reference electric characteristic that is a reference electric characteristic, by using a learning model for estimating an electric characteristic inherent to the apparatus from the gap current value and the applied voltage value, based on the electrode current value and the applied voltage value. ADVANTAGEOUS EFFECTS OF INVENTION The present invention provides an electric discharge machine capable of suppressing degradation of machining quality. Drawings Fig. 1 is a diagram showing a configuration of an electric discharge machine according to embodiment 1. Fig. 2 is a diagram showing a configuration of a learning device included in the electric discharge machine according to embodiment 1. Fig. 3 is a diagram showing an example of the structure of a neural network used in the learning device according to embodiment 1. Fig. 4 is a flowchart showing a flow of processing performed when the electrical characteristics of the electric discharge machine according to embodiment 1 are corrected. Fig. 5 is a diagram showing a waveform example of the interelectrode current value obtained by the electric discharge machine according to embodiment 1. Fig. 6 is a diagram for explaining a process of estimating the impedance and parasitic capacitance value in the electric discharge machine according to embodiment 1. Fig. 7 is a diagram for explaining a range in which correction can be performed by the electric discharge machine according to embodiment 1. Fig. 8 is a diagram showing a configuration of an electric discharge machine according to embodiment 2. Fig. 9 is a diagram showing a machining circuit of a machining section in the case where machining poles of the electric discharge machine according to embodiment 2 are separated. Fig. 10 is a diagram showing an equivalent circuit corresponding to the processing circuit of fig. 9. Fig. 11 is a diagram for explaining the impedance and the phase delay in the case where the machining gap calculated by the electric discharge machine according to embodiment 2 is in a separated state. Fig. 12 is a diagram showing frequency characteristics in the case where the machining gap calculated by the electric discharge machine according to embodiment 2 is in a separated state. Fig. 13 is a diagram showing a machining circuit of a machining section in the case where the machining gap of the electric discharge machine according to embodiment 2 is in a short-circuited state. Fig. 14 is a diagram showing an equivalent circuit corresponding to the processing circuit of fig. 13. Fig. 15 is a diagram for explaining the imped