GB1365356A - Pneumatic spring devices - Google Patents

Abstract

1365356 Gas-spring power-storing mechanisms J L GRATZMULLER 4 Nov 1971 [13 Nov 1970] 51261/71 Heading F2S [Also in Division H1] A gas spring has a cylinder 71 in which moves a structure such as a plunger, piston or an arrangement, such as that shown, with an unattached piston 89 while the plunger (in the form of a rod), or a rod such as 79 of the structure, extends out of at least one end, e.g. for linking to a movable contact of an electric circuit-breaker (see Division H1); a chamber 93 between the structure and the cylinder is filled, e.g. by way of a valve 33, with gas (such as H 2 , He or Ne) which under normal temperature and pressure has a density less than that of N 2 and which is under a pressure between 300 and 1000 bars. The spring may include a chamber 87 supplied with hydraulic fluid through an inlet 86 to act on a piston 81 to compress the spring to load it, in which case the piston-rod 79 may have an extension 85 beyond the piston 81 and abutting the spring piston 89. The extension is in a chamber 90 between the pistons and open to atmosphere through an orifice 96. The relative positions of the pistons 81, 89 may be interchanged, Fig. 6 (not shown), so that instead of urging the rod 79 into the cylinder the piston 81 urges it out, until the spring is required to operate and release its stored energy. The spring is released by voiding the chamber 87. In another embodiment, Fig. 7 (not shown), the two pistons 81, 89 are adjacent one another at one end of the rod 79 with which they are integral and are separated by a peripheral groove (97) which, together with radial passages (99) in the rod, forms the intervening chamber 90 and communicates with the atmosphere by way of an axial channel (101) through the rod. The seals for the plunger, piston or piston-rod each comprise a spring-compressed packing 77, 83 or 91 of a number of elastomeric rings of different elastic properties. For a plunger or rod, the seals are stationary. A simple spring, without an hydraulic chamber, Fig. 3 (not shown), having a piston (37<SP>1</SP>) urged into the cylinder (1) by the compressed gas, has a chamber (43), on the opposite side of the piston, which as a breather valve (45) to atmosphere. In another embodiment, Fig. 4 (not shown), a plunger (55) extends out of both ends of the cylinder (1) and has two sections of different diameters for providing the differential pressure and stops (57, 59) on it for limiting its travel. According to which exposed end of the plunger is connected to a member to be moved, the member is pushed or pulled on release of the spring.