| 摘要 |
PCT No. PCT/US79/00738 Sec. 371 Date Sep. 11, 1979 Sec. 102(e) Date Sep. 11, 1979 PCT Filed Sep. 11, 1979 PCT Pub. No. WO81/00796 PCT Pub. Date Mar. 19, 1981. In the control of two or more electrical devices powered by a common battery and each actuated by a separate controlled rectifier chopper circuit, at least one of which is an SCR chopper circuit, under high stress conditions requiring both electrical devices to be repeatedly and rapidly turned on and off it has been found that control over the SCR chopper circuit can be lost due to inherent inductive effects which prevent the charging of the commutating capacitor of the SCR chopper to at least full open circuit battery voltage. This problem is met by inhibiting the occurrence of an "off" actuation control signal to the SCR chopper circuit for a given period of time before and a given period of time after an "on" actuation control signal to the other chopper circuit. Thus, in a battery powered lift truck, for example, having a drive motor and a lift pump motor each actuated by an independent SCR chopper circuit, an "on" actuation control signal to the drive motor circuit is sensed and any "off" actuation control signal to the lift pump motor circuit is inhibited for a few hundred microseconds before and a few hundred microseconds after the drive motor circuit is actuated to allow the battery to return to at least full open circuit voltage before the pump motor circuit is turned off.
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