GB1115664A - An improved retractable door assembly - Google Patents

Abstract

1,115,664. Pressure-resisting doors. SECRETARY OF THE NAVY, U.S.A. 23 March, 1966, No. 12859/66. Heading F2P. [Also in Division F3] An access door assembly for a missile launching tube 1 comprises a door 30 provided with an insert 31 of moulded plastics material and formed with slots 33 which allow the eject pressure of a missle launching atmosphere to act against the door, the latter including a flange 35 provided with spaced lugs 37 tapered to form cam surfaces and engageable behind dogs 22 on a clamping ring disposed about the aperture in the tube 1 and having a spur gear segment 84; a retaining ring 81 carries a sleeve 85 which journals a pinion which meshes with the segment and rotation of the pinion results in rotational movement of the ring 80 to interengage the lugs 37 and dogs 22. The door is mounted pivotally on a yoke 40 which is hinged to a shaft 45 having pinions 43, 44 meshing with gear tracks 41, and secured to the tube 1 are support tracks 47, 48 that receive carriage assemblies 49. The door is connected to a guide rod (28), Fig. 2 (not shown), by a link (27) and an arm (25) hinged on a shaft (26), and an adjustable stop (29) allows alignment of the door with the aperture in the tube 1. In opening the door from the locked position thereof, the dogs 22 and lugs 37 are disengaged by rotating the clamp ring 80 and by pulling on a strap 54 the door is retracted from the aperture and moved along the tracks 47, 48. A trigger 57 on the handle 55 of the strap operates a flexible control cable 53 at the end of which is a spring-loaded plunger 61 adapted to engage between two teeth of the pinion 43 to provide for braking of the movement of or to lock the door in a particular position. A motor (60), Fig. 6 (not shown), operated by controls on the strap 54 and through the cable 53, may be provided to drive a geared shaft (62) to move one or both of the pinions 43, 44 and thereby retract the door. A latching mechanism 90 including a spring- loaded pin 91 may engage between two teeth of the pinion 86 to prevent the pinion turning, and an interlock assembly 100 closes an electric circuit to indicate that the door is locked in place.