Patent GB-871851-A (GB)
Title: Pressure door
IPC: F23M7/00
Filed: 1959-05-29
Abstract: 871,851. Pressure doors. CHICAGO BRIDGE & IRON CO. May 29, 1959 [June 12, 1958], No. 18298/59. Class 123(1) [Also in Groups XXI, XXV and XL(a)] A pressure door 10, with emergency escape and locking mechanism, e.g. for autoclaves, airlocks, and nuclear reactor vessels, is mounted by a double-hinged arm 14 to a bulkhead 12 and has a peripheral flange 11 which carries a number of circumferentially-spaced cams 23 which cooperate with corresponding pairs of cam rollers 21 mounted radially inwardly on the door side of roller mounts 20 which depend laterally, at spaced intervals, from each side of a locking ring 17. The latter is rotatably mounted on the outer face of a flange 24 which extends around a door opening in the bulkhead 12 and co-operates with the flange 11 when the door 10 is closed. The locking ring 17, guided by pairs of rollers 19 which are fitted to the bulkhead side of the roller mounts 20 and engage the sides of a guide rail 18 upstanding from the outer face of the flange 24, is supported by rollers 22 which are attached to its underside, and ride upon the outer peripheral face of a face flange 26 of the flange 24. To open the door a lever 34 is pulled down which, through gearing 33 and a shaft 32, rotates a pinion 31 which co-operates with a rack 30 on the locking ring 17 to move the latter counterclockwise. During the first part of the rotation of the ring 17 a pressure equalization valve 50 located in the bulkhead 12 is opened a pinion 57, which co-operates with the rack 30, operating link mechanism 56 connected to the valve 50 and Geneva mechanism, 51. During this time, the cam rollers 21 travel along the straight, circumferentially aligned, portions 23a of the cams 23 so that the door remains in its sealed position. Continued rotation of the locking ring 17 brings the cam rollers 21 into contact with the machined oblique surfaces 23b of the cams 23 to unseal the door and free the latter for opening as the cams 23 and rollers 21 disengage. Further rotation of the ring 17 actuates a linkage 80 through a Geneva mechanism 61 actuated by a pinion 71 which engages a rack 70 on the locking ring 17 and is connected to the mechanism 61, through gearing 72, so that the door is swung open. The door is guided into its closed position by a pin 95 which is located on the door flange 11 and is engageable in a recess in a bracket 96 attached to the face flange 26 of the flange 24, the reverse sequence of operations being carried out when the door is closed. A projecting ring 100 on the inner edge of the door flange 1 engages a gasket 101 in the outer edge of the flange 24 when the door is closed, the space between each pair of rollers 21 being greater than the width of the cam portions 23a of the corresponding cam 23 to allow for the higher sealing pressure within the vessel. Stops 103, peripherally spaced on the door flange 11, limit the penetration of the ring 100 into the gasket 101. The locking ring 17 can also be rotated by means of a gear, sprocket, and chain, arrangement, Fig. 3, which otherwise in its general construction, is the same as that shown in Figs. 1, 2. In an airlock, Fig. 4, door opening control mechanisms are provided so that each door can be operated from either side of the bulkhead, the doors being mechanically interlocked so that both doors cannot be opened at the same time and one door cannot be opened unless the opposite door is sealed. An additional operating lever 105 is provided in the interior of the bulkhead 12 to operate the exterior door. The doors operate in a manner substantially the same as the door Fig. 1. With a generally rectangular hinged door 125, Fig. 10, having a peripheral flange 126 with cams 127 a number of roller mounts 142 are interconnected by flexible links 148 which pass over sheaves 149 mounted on the bulkhead 128, the vertically disposed mounts 142 being additionally guided by angle guides 159 which slide between roller guide pairs 160 rotatably mounted on brackets 161 fixed to the bulkhead 128. The door is guided into a closed position by means of pins 162 which are carried on the flange 126 and engage slotted guides fastened to the bulkhead 128. The doors may be operated electrically or hydraulically, emergency installation being manually controlled to permit operation in the event of power failure.