Engineering topics
Publications and source records attributed to King, Guy L..
Double-swivel toggle mechanism releases large, heavy objects reliably. Double-swiveling action of mechanism ensures it clears restraining pins upon release. Pins retain toggle and its load. If pin fails to withdraw at designated time for releasing payload, toggle swivels about its upper ball, and ring swivels about lower ball so ring flange clears failed pin. Double-swivel action ensures disengagement even it two pins fail to withdraw.
A pyrotechnic actuated structural release device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body each attachable to one of a pair of structures to be joined. The fastener plate and the fastener body are fastened by a dual swivel toggle member. The toggle member is supported at one end on the fastener plate and mounted for universal pivotal movement thereon. Its other end is received in a central opening in the fastener body, and has a universally mounted retainer ring member. The toggle member is restrained by three retractable latching pins symmetrically disposed in equiangular spacing about the axis of the toggle member and positionable in latching engagement with the retainer ring member on the toggle member. Each pin is retractable by a pyrotechnic charge, the expanding gases of which are applied to a pressure receiving face on the latch pins to effect retraction from the ring member. While retraction of all three pins releases the ring member, the fastener is mechanically two fault tolerant since the failure of any single one or pair of the latch pins to retract results in an asymmetrical loading on the ring member and its dual pivotal movement ensures a release.
The NASA Stabilized Payload Deployment System (SPDS) is discussed. The lightweight and heavy-duty system rolls payloads over the orbiter's side rather than ejecting them upward. The system will enhance the orbiter capability of carrying larger and heavier payloads. The design, function, and analysis of a new three-pin double swivel toggle release mechanism which is crucial to the successful deployment of the SPDS are described.