Patent GB-636962-A (GB)
Title: Improvements in or relating to x-ray examination tables
IPC: A61B6/04
Filed: 1947-08-08
Abstract: 636,962. Rontgen-ray examination tables. WESTINGHOUSE ELECTRIC INTERNATIONAL CO. Aug. 8, 1947, No. 21832. Convention date, Nov. 27, 1941. [Class 98 (i)] [Also in Groups XXIV and XXXIV] The table comprises a base, a table top pivoted to the base, and operating mechanism for moving the table top about its pivot comprising a flanged plate forming a brake drum carried by a stationary part of the table, a manually-operated member forming a cover for the flanged plate and pivoted thereto, a pair of webs projecting from the inner surface of the manually-operated member, a member pivoted with respect to the brake drum and carrying a stop element, a pair of brake shoes within the drum, means pivoting two adjacent ends of the shoes to the stop-element carrying member, a spring normally urging the free adjacent ends of the shoes into braking engagement with the drum, a linkage-operating member also pivoted to the stop-element-carrying member for movement between the stops, resilient means normally holding this operating device in neutral position, actuating links extending from this device to a free part of each shoe, and a part of this device normally received between the webs for actuation to release the shoes upon movement of the manually-operated member in either direction, until one of the webs engages one of the stops to turn the stopelement-carrying member and thereby to turn the table. As shown, Fig. 2, a flanged piate 18 is secured in a recess in a hollow member 5, which forms one support in which the table top is pivoted. A plate 20 secured to the plate 18 has two bearings 23, 24. A sprocket 27 and a gear wheel 32 are fixed to a shaft 26, journalled in the bearing 24 and a bearing 25 in the plate 18. A plate 36 rotates in a bearing 39 in the plate 18 and is fast with a shaft 35 rotating in the bearing 23 and on which a gear wheel 33, meshing with the wheel 32, is keyed. A disc 60 with a pivoted handle 62 rotates freely on an extension of the shaft 37 and is retained by a nut 63. A T-shaped member 40, see also Fig. 3, pivoted to the plate 36, carries a roller 42 engaged between lugs 64 formed on the inner surface of disc 60, and is jointed by links 43, 44 to brake shoes 45, 46 pivoted to the plate 36 and urged to engage the flange of plate 18 by a compression spring 49. When the disc 60 is turned clockwise, lugs 64 rock the member 40, pivoting the brake shoes 45, 46 by links 43, 44 to raise them from the flange. The plate 36 can thus rotate when the lug 64 contacts an adjustable stop screw 56. When the disc 60 is released, springs 57, 58 attached to the lugs 64 and to the plate 36 return it to its original position relative to the plate 36, in which the brake shoes again engage the flange. The plate 36 can be similarly rotated in the other direction, and in either case drives the sprocket 27 through gears 33, 32. The sprocket drives, by a chain 29, a second sprocket, not shown, and a gear wheel engaging a toothed segment fixed to the table top which is thereby rotated. An X-ray tube and a fluorescent screen may be movably mounted on the table.