Patent GB-1005186-A (GB)
Title: Improvements relating to clamps
Inventor: LOBELLE MARCEL JULES ODILON
IPC: A62B18/04
Filed: 1961-03-14
Abstract: 1,005,186. Clamp fastenings. M. L. AVIATION CO. Ltd. March 9, 1962 [March 14, 1961], No. 9311/61. Heading E2B. [Also in Division B7] A clamp for securing together two circular flanged members of similar diameter against relative axial movement away from each other comprises a mounting ring 14, part of which is for positioning behind the flange 4 of one of the flanged members, and carrying at least one radially movable clamping member 29, the radial position of which or each of which is controlled by an operating ring 20, mounted so as to be able to rotate relatively to the mounting ring with an action such that relative rotation in one sense causes the or each clamping member to move radially inwards to engage behind the flange 3 of the other flanged member over a substantial part of the circumference thereby securing the flanged members against relative axial movement away from each other while relative rotation in the opposite sense causes the or each clamping member to move radially outwardly to permit the two flanged members to be withdrawn away from each other. As shown the flanged members are part of a helmet 2 and a flying suit. The mounting ring 14 has an internally directed lip 15 between which and the upwardly directed flange 4 attached to the neck of the suit a series of balls 16 are positioned so that the mounting ring is rotatable relative to the suit neck. The balls 16 are retained by a ring 18. The flange 4 is part of a ring 5 between which and a second ring 8 the fabric neck 1 of the suit is clamped by bolts 6. The bolts 6 also hold in position a ring 11 and three plates 10, the plates each having a lip 13 which bears against the lower surface of the mounting ring 14 to prevent its removal from the ring 5. The mounting ring carries six of the clamping members 29 which are slidable mounted in grooves in the ring 14 so that their inner edges 30 can project inwardly into contact with a groove 31 formed round the edge of the flange 3 of the helmet. Each clamping member has two cam slots 27 and in each cam slot is a sleeve 23 which is carried by the operating ring 20. Thus rotating the operating ring relative to the mounting ring moves the clamping members radially. The operating ring is moved by means of a lever 32 which is pivoted to the operating ring and connected to the mounting ring by means of two pivoted arms 36. The lever 32 is formed with a head 41 having spring edges 42 which project inwardly and in the clamping position of the members 30 the spring edges snap over locating studs 43 on the operating ring. The mounting ring has cutaway sections at intervals round its inner surface for receiving locating blocks carried by the helmet to locate the ring with respect to the helmet; the mounting ring also carries a plurality of spring-loaded plungers 53 which can engage the groove 31 in the helmet to align the clamping members with the groove. To enable the suit to be pressurised, a low friction sealing ring made of material such as polytetrafluorethylene is compressed between the ring 5 and a projection 58 of the helmet. In a modification instead of the six clamping members 30 a single clamping member in the form of a split ring is provided which is compressed so that it engages the groove 31 by means of equally spaced rollers engaging its outer circumference, the rollers being moved by cam surfaces on the inner surface of the operating ring. Instead of the operating ring being moved by a lever it may have a knurled outer surface to enable it to be moved directly.