EP0260963A2
Expired / Lapsed
EP
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Inverter-type resistance welding machine
Assignee: Toshiba Corp
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Filing: 1987-09-17
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Granted: —
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Expires: 2007-09-17
Abstract
Abstract The present invention is directed to an inverter-type resistance welding machine. A PWM inverter supplies high frequency primary voltage to a transformer. A microprocessor controls the PWM inverter by proportional-integral-deviation (PID) control through a PWM control unit. The microprocessor determines a feedforward operation amount which corresponds to a desired welding current value before current is supplied to the welding electrodes. The time period for the calculation of an integral operation amount is effectively reduced to approximately zero by employing a calculated integral operation amount from a previous sampling.
Inventors
- 👤 Takatomo§Patent Division§Toshiba Corp. Izume
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 10:40
CPC Classifications
B; B23; B23K; B23K11/00; B23K11/24; B23K11/25; B23K11/252; B23K11/256; H; H02; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
128 words
An inverter-type resistance welding machine comprising power supply control means adapted to be coupled to a source of AC power for providing a controlled welding current flow; welding electrodes coupled to said power control means for receiving said controlled current flow; means for supplying a feedforward operation amount corresponding to a desired welding current before said current is supplied; and control means coupled to said power supply control means for controlling the operation of said power control means, said control means being arranged to determine a proportion value, an integral value and a difference value in controlling the operation of said power control means, wherein the integral operation time is reduced to approximately zero by employing a calculated value of a previous sampling as an integral operation amount.
Claim 2
Dependent Claim
128 words
An inverter-type resistance welding machine comprising power supply control means adapted to be coupled to a source of AC power for providing a controlled welding current flow; welding electrodes coupled to said power control means for receiving said controlled current flow; means for supplying a feedforward operation amount corresponding to a desired welding current before said current is supplied; and control means coupled to said power supply control means for controlling the operation of said power control means, said control means being arranged to determine a proportion value, an integral value and a difference value in controlling the operation of said power control means, wherein the integral operation time is reduced to approximately zero by employing a calculated value of a previous sampling as an integral operation amount.
Claim 3
Dependent Claim
23 words
The welding machine of claim 1 further including rectifier means for rectifying said AC power for application to said power supply control means.
Claim 4
Dependent Claim
21 words
The welding machine of claim 1 further including a transformer connected between said power supply control means and said welding electrodes.
Claim 5
Dependent Claim
26 words
The welding machine of claim 3 further including rectifier means for rectifying the output of said transformer to provide said weld current to said welding electrodes.
Claim 6
Dependent Claim
14 words
The welding machine of claim 1 wherein said control means includes a PWM controller.
Claim 7
Dependent Claim
15 words
The welding machine of claim 5 wherein said PWM controller is controlled by a processor.
Claim 8
Dependent Claim
50 words
The welding machine of claim 1, wherein an arithmetic mean of previous operation amount and a present operation amount in the positive half cycle of said power source means is output to said PWM control circuit, and operation amount of the present time in the negative half cycle is output.
Claim 9
Dependent Claim
16 words
The welding machine of claim 1 wherein said operation amount is limited to a predetermined value.
Claim 10
Dependent Claim
13 words
The welding machine of claim 6 wherein said processor is an 8-bit micro-computer.
Claim 11
Independent Claim
131 words
A method of controlling a welding machine, said method including the steps of; providing power supply control means adapted to be coupled to a source of AC power for providing a controlled welding current flow; providing welding electrodes coupled to said power control means for receiving said controlled current flow; providing control means coupled to said power supply control means for controlling the operation of said power control means, said control means determines a proportion value, an integral value and a difference value in controlling the operation of said power control means, wherein the feedforward operation amount corresponds to a desired welding current value before said current is supplied and the integral opration time is approximately zero by employing a calculated value of a previous sampling as an integral operation amount.
Claim 12
Independent Claim
131 words
A method of controlling a welding machine, said method including the steps of; providing power supply control means adapted to be coupled to a source of AC power for providing a controlled welding current flow; providing welding electrodes coupled to said power control means for receiving said controlled current flow; providing control means coupled to said power supply control means for controlling the operation of said power control means, said control means determines a proportion value, an integral value and a difference value in controlling the operation of said power control means, wherein the feedforward operation amount corresponds to a desired welding current value before said current is supplied and the integral opration time is approximately zero by employing a calculated value of a previous sampling as an integral operation amount.
References Cited (Backward Citations)
No citation records indexed.
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