| 摘要 |
A circuit is provided for apparatus of the type in which a member is reciprocated through a work stroke relative to a support on which work is placed and from which it is removed by the operator. Typical operations are cutting and forming. The circuit includes two parallel leads and a pair of switches in control of both leads, one switch for each hand of the operator. The switches are normally closed with reference to the first lead. The second, normally open lead includes a device which, when energized, initiates the work stroke and the first lead includes means enabling the second lead to be closed relative to the device if the operator actuates both switches but the means of the first lead cannot again be operated unless and until both switches are in their normal position.
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