GB1086058A - Improvements relating to releasable couplings - Google Patents

Abstract

1,086,058. Cable grips; screw and nut gearing. FAIRY ENGINEERING Ltd. July 31, 1964 [Aug. 2, 1963], No. 30837/63. Headings F2Q and F2X. Sample carriers 12, 15 oscillating in an exchangeable nuclear reactor core void are attached to double cable loops 13 releasably coupled to a single driving oscillating cable loop 18 by a coupling 19 comprising, a block 60 in the cable loops 13 having spring-opened jaws 63 and a block 61 in the cable driving loop 18 adapted to be held by the jaws 63, which have overlapping tails 67 depressed by the block 61 when it is inserted between the jaws 63 so that the jaws pivot to embrace and hold block 61. The block 61 has edge channels 65 axially held and gripped by jaws 63. The jaws 63 are sprung by leaf springs 68 and pivoted at 66. When the jaws have been closed by the entry of block 61, a bolt 70 is shot by springs 77 into aligned jaw-tail holes 71 locking the jaws. To release the jaws a key 80 pushes the bolt 70 out of holes 71 until its reduced centre portion 83 lies in holes 71 allowing the jaws 63 to spring open. Whilst jaws 63 are open the key, which also starts the main drive motor, may not be removed from block 60. A ball catch helps to retain the key 80 in the block 60. Blocks 60, 61 are pivotally attached to the eyed-ends of cables 13, 18. The cable loops 13, 18 have tensioners 14a, 20a, one of which 14a is sprung. The driving cable loop 18 is driven from a rotatably oscillated drum 21 fast on a rotatable but axially restrained recirculating-ball nut 34 engaged by a reciprocating non-rotatable lead screw 32 integral with an hydraulic ram 28. The nut 34 has two parts 34a, 34b preloaded by contra-rotation to take up backlash, and runs in a fixed housing race 35. The lead screw 32 has longitudinal grooves 38 engaging with a re-circulating ball keying sleeve 40, Fig. 5. The ram is operated from a pump-fed hydraulic accumulator 50 through an electric servo valve 29 receiving signals from a remote control panel. Valves 52 relieve the pump when the accumulator shut-off valve 51 is closed. The cable drum 21 is electromagnetically braked at 54 and has an angular-position feedback potentiometer 57. An auxiliary hand and/or electric motor driving cable loop 23 (Fig. 3) is provided having a coupling block 61 for selective coupling to the block 60 in cables 13. Cable 23 is wrapped around a drum 90 driven by a motor 92 or hand wheel 91 with a revolution counter 93. Limit switches 96, 97 triggered by block 61 on loop 23 stop the electric motor 92 so that the carriers 12, 15 may be hand driven to a loading position. Switches 98 triggered by the coupling 60, 61 signal the limits of carrier travel to the control panel. The double carrier cable loops 13 are carried by pulleys 14 and the vertical portion carrying carriers 12, 15 is hung from an arm so that it is adjustable angularly and radially.