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Pneumatic Circuit Override

IP.com Disclosure Number: IPCOM000074796D
Original Publication Date: 1971-Jun-01
Included in the Prior Art Database: 2005-Feb-23
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Livesey, AG: AUTHOR

Abstract

In testing semiconductor modules, the modules are loaded into nests on a rotary turntable. This pneumatic circuit senses a slow turntable operating speed or a stopped condition to activate an override.

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Pneumatic Circuit Override

In testing semiconductor modules, the modules are loaded into nests on a rotary turntable. This pneumatic circuit senses a slow turntable operating speed or a stopped condition to activate an override.

After straightening and aligning the pins, the turntable rotates through test stations where contact is made with individual air actuated sockets. Provided that the turntable rotates at a fixed operating speed, the timing of the entry of the module pins is controlled with a pretimed air cam for the socket closure. The pretimed air cam is set to start the socket closure during the latter part of the indexing rotation for the turntable, insuring early socket closure at the station.

The rotation of the turntable and the operation of the sockets is pneumatically controlled through an adjustable manifold. Recognition is made of a slower operating speed or a stopped condition by the pneumatic circuit to prevent closure of the socket by the pre-timed air cam. The override pulse that is provided is time-delayed and inhibits the closure of the socket only if the slow speed or stop condition is detected. It is not recognized at normal operating speeds. In this way, the bending of module pins due to the changes in operating speed is prevented.

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