Patent GB-404899-A (GB)
Title: Pressure-resisting closure for watertight compartments of ships
IPC: B63B19/00
Filed: 1933-08-23
Abstract: 404,899. Doer-operating apparatus; holders for sliding-doors. MATTEI, D., 36, Via XX Settembre, Genoa, Italy. Aug. 23, 1933, No. 23428. [Classes 44 and 65 (i).] In apparatus for operating sliding bulkhead doors of ships, the door on reaching its closed position brings into action mechanical means for pressing it against its frame. The door closes under its own weight, or in the case of horizontally moving doors under the action of a separate weight, when released either from a distant control point or automatically in case of fire or flooding; when closed, the door can be locked in that position from a distance or automatically on entry of water. Opening of the door may be effected by pneumatic power, controlled locally, or by manual power which may be combined with power operation controlled from a distance. In the form shown, a vertically sliding door 1 is supported by cables 2 passing over pulleys 3 and attached to the piston rod 5 of a pneumatic cylinder 4 to which compressed air is supplied, to open the door, from a reservoir 17 under control of a valve 18 ; the valve 18 connects the cylinder 4 either to the reservoir 17, for opening the door, or to exhaust, for closing the door, a whistle 18<1> being brought into action in the door-closing position. The means for pressing the door against its frame when closed comprise cams 6 pivoted eccentrically and connected by cranks 8 and rod 9 to a lever 10, to which is attached an operating spring 12 and a releasing cable 28 ; the cams are held out of action, when the door is open, by a pivoted pawl 13 engaging a lug 14 on the rod 9, but this pawl is released by an adjustable roller 16 on the door as the door reaches the closed position. Wedges may be used in place of the cams 6. The door is held open by a pivoted catch 24 on the frame engaging a keeper 25 on the door under the action of a spring 23 tensioned by a cable 22 attached to the operating arm 19 of the valve 18 ; in the door-closing position of the valve, as shown, the tension of the spring is reduced, and the holding catch 24 is moved clear of the keeper 25 by a spring 26, thus allowing the door to fall. To open the door, a lever 27 is pushed downwards, releasing the clamping cams by cable 28 and moving the valve arm 19 in an anti-clockwise direction to admit compressed air to the cylinder 4; this movement of the arm 19 pulls the catch 24 back to its engaging position, to snap over the keeper 25 under the action of spring 23 when the door is fully open. In the door-opening position of the valve 18, a lug 20<1> on the operating arm 19 snaps behind a detent 21 biassed by a spring acting on its tail 211 ; the valve is thus held in this position until the detent is released, when it is moved to the door-closing position by the pull of spring 23 on the arm 19. The detent 21 may be released by a solenoid 41, by a spring 42 released by a fusible device in case of fire, or by a float 40 in case of flooding. When the door is closed its opening may be prevented by a detent 29 entering a notch in a rod 30 attached to the lever 27 to prevent movement of this lever ; the detent 29 may be moved to the engaging position by a solenoid 281 or a float 31. In one form of the apparatus for opening the doors by manual power instead of by pneumatic means, the cables 2 are wound on a drum provided with a crank handle and a ratchet, with a pawl corresponding to the detent 21 and acting in the same way ; the door is partly balanced by a counter-weight attached to it by separate cables. In this form the holding catch 24 is dispensed with, its place being taken by the ratchet pawl on the winding drum, and the detent 29 for locking the door closed merely prevents release of the clamping cams ; the whistle 18<1> is replaced by a bell operated by a toothed wheel on the operating shaft. In a modification, the cables 2 are attached to a hanging rack and counterweight operated by a toothed wheel which takes the place of the winding drum. In a further modification for manual opening, the winding cables 2 pass on from the winding drum to support the counterweight ; in this form the detent 29 for locking the door closed acts on the rod 9 connected to the clamping cams, and the spring 42 for release of the main detent in case of fire is replaced by a weight. An electric signalling system indicates on the deck whether the door is open or shut and whether the main detent is released ; if the detent is released, the door cannot remain open, and an acoustic warning is given, a prolonged sound indicating that the closing of the door is obstructed. This form of the apparatus may be modified for opening by power under distant control in addition to the manual means. In this modification the counterweight is replaced by a heavy cylinder sliding over a fixed piston, and another cylinder sliding on a fixed piston actuates the clamping cam release lever, being normally held in the non-release position by springs. A valve operated by solenoid or manually admits air to both cylinders to release the clamps and open the door ; when released, the valve is returned by a spring to the exhaust position, the door remaining open under the action of the winding drum detent, and the clamping cam release cylinder is returned to its normal position by its springs, the cams being held released by the pawl 13. In a modification of the apparatus for doors sliding horizontally, a pinion on the manual crankshaft operates a rack fixed to the door and a drum on the shaft raises a weight which produces the closing force ; the release means and power-operating apparatus, if provided, are the same as for vertically moving doors.