Patent GB-538706-A (GB)
Title: Improvements in x-ray apparatus
IPC: H05G1/04
Filed: 1940-05-20
Abstract: 538,706. R÷ntgen-ray apparatus. BRITISH THOMSON-HOUSTON CO., Ltd. May 20, 1940, No. 8953. Convention date, May 20, 1939. [Class 98 (i)] In a mounting for an X-ray tube housing in which the housing is tiltable about a plurality of axes in relation to mounting means by which it is carried so as to be spaced from, and longitudinally adjustable in relation to, an elongated support member, the mounting means comprises a bracket longitudinally movable on the support member and having an outstanding supporting arm pivoted to it so that the housing may be adjusted in a circular arc about the support member. As shown, the tube housing 17 is pivotally mounted in a yoke 39 having a stem 41 rotatably carried by an arm 45 hinged on a vertical axis to a frame 63, which is vertically movable on a hollow standard 61. The standard comprises sheetmetal plates 62 having secured between them steel strips 65 which form external tracks for rollers on the frame 63 and internal tracks for rollers carried by a counterweight 64 which is connected to the frame 63 by cords 67 passing over sheaves 69. The standard is carried by a bracket 71 forming part of a frame 74 which is adjustable transversely of the table 15 on rollers 75 carried by a frame 79, the latter being adjustable longitudinally of the table on tracks 83. The table may be tilted by rack and pinion gearing, the frame 79 and parts carried by it being balanced when the table is so tilted by a counterweight 85 movable on tracks 87 and connected to the frame by cords passing round sheaves at the ends of the frame which carries the table. A cassette holder 33 is adjustable on tracks longitudinally of the table. To position the X-ray tube beneath the table it is swung clear of the table to the rear by releasing a pivoted latch 56 which holds the carrying-arm 45 in its forward position and turning the arm to the rear on its hinged connection to the frame 63, the latch being reversed to retain the arm in this position. The frame 63 is then lowered to the bottom of the standard, which extends below the table, the tube housing is inverted, swung beneath the table, and raised into contact with a seating 54 in the frame 74, against which it is pressed by a spring buffer 98 acting on the frame 63. The yoke 17 carrying the tube housing is rotatable about the axis of the stern 41, and is held in adjusted angular position by a spring detent engaging a notched disc. The stem 41 is slidable in the end of the arm 45, allowing the X-ray tube to be adjusted transversely of the table. A fluorescent screen 151 carried by an arm 153 pivoted on the bracket may be swung down over the table. A shutter in the frame 74 is actuated through a cable from a control 159 adjacent the screen. The tube housing is formed with a cylindrical cavity 27 having end covers 47, and with a pair of spaced chambers 107 in which are sealed re-entrant socket members 113 to receive jacks at the ends of the anode and cathode cables. The tube is supported by brackets 115, 121 carried by the socket members. The housing is oil-filled, its interior communicating with a spring- pressed expansion chamber 145.