Improvements in or relating to hatch covers or like closure devices

摘要

655,199. Hatch covers. HAY, S., and SWEET, C. W. May 10, 1948, No. 12838. [Class 113 (i)] In a hatch cover comprising sections 10 hinged to one another at 11 so as to fold concertina fashion, each pair of adjacent hatch sections is provided with spring means arranged when the hatch is in the open position to exert an initial force between said adjacent sections to cause the hatch cover to close by gravitation. The cover is provided with a cable 15 and pulley blocks 19, 20, for drawing together the end sections, rollers 13 on each side of each section engaging tracks on the ship structure, a ramp 23 engageable successively by alternate rollers, and fitting adjacent the stowing position for tilting the end section and limiting its translatory movement. The spring means comprises a spring 39 surrounding a shaft 38 fitted in lug members 34, 37 secured to adjacent cover sections, one end 40 of the spring being secured to one cover section and the other end 42 being secured to the adjacent section. The spring is initially stressed so that when cover sections are closed they tend to open them, but on opening the cover this stress is overcome and is reversed so that cover is finally locked in the open position with the springs urging the sections to move to the closed position. The initial stress in the spring provides for shock absorption during the final closing stage. Specification 607,163 is referred to.