GB948733A - Improvements in and relating to remotely controlled gas-operated grabheads - Google Patents

Abstract

948,733. Remotely controlled grippers for lifting articles. ENGLISH ELECTRIC CO. Ltd. June 17, 1960 [June 19, 1959], No. 21121/59. Heading B8H. [Also in Division G6] In a remotely-controlled grab-head a remotely-controlled valve 41 controls the flow of gas from a reservoir 12 to actuating mechanism 43 which moves jaws 11 between gripping and non-gripping positions. The reservoir 12 is charged through a non-return valve 16 by temporarily enclosing the grab-head in a vessel containing gas under pressure. In operation, an electrically-controlled valve 33 is energized to admit gas from the reservoir 12 to a cylinder 22, thus moving a jaw carrier 20 down to its lowest position so that the jaws are as shown in dotted lines. The grab-head is lowered until a lower contact ring 48 of a probe 47 engages with a contact ring 54 in a socket 53 in a fuel element 10. The valve 41 is next energized to admit gas to a chamber 36, thus lowering the actuating mechanism 43 which forces the jaws inwardly to engage their hooked ends 50 in the annular recess 51. This downward movement also inserts the probe 47 further into the socket 53, thus engaging the lower contact ring 48 with a contact ring 56, and the upper ring 48 with the ring 54. These contact rings operate indicators for the operator of the grabhead. The valve 33 is now de-energized and gas is exhausted from the cylinder 22 as the jaw carrier 20 and the actuating mechanism are raised by a spring 30, with the hooks 50 engaged in the recess 51. The valve 41 is then deenergized but the mechanism 43 remains in the extended position owing to the self-gripping action produced by the shape of the jaws. When the element 10 is placed on a supporting surface the self-gripping action is released and a spring 38 raises a cam 44 to open the jaws. In a second embodiment the spring 38 is disposed above instead of below a piston 37, thus holding the jaws closed, the jaws being opened by gas pressure acting beneath the piston 37.