Patent GB-385655-A (GB)
Title: Improvements in shock absorbers
IPC: F16F9/14
Filed: 1931-07-24
Abstract: 385,655. Hydraulic shock-absorbers. GABRIEL CO., 1407, East 40th Street, Cleveland, Ohio, U.S.A. July 24, 1931, No. 21215. Convention date, Nov. 8, 1930. [Class 108 (iii).] In an hydraulic shock-absorber o f the kind in which a cylindrical casing with closed ends is provided with a partition extending between the two ends and forming a working chamber in which a vane is adapted to oscillate, a slide valve regulating the passage of liquid through a passage in the partition is controlled by a thermostat in accordance with the temperature of the liquid in the casing so as to maintain a constant throttling effect. In the construction shown in Figs. 2, 4, 5, and 6, the cylindrical casing 3 is bolted to the side frame 1 of the vehicle and the operating spindle 48 carrying the vane 41 is connected to the axle. The working chamber is formed by a projection 5 from one side of a block 4 whose inner face thus forms one wall of the working chamber. The block also provides a chamber 8 carrying a reserve of liquid which is supplied when required to the working chamber through a oneway valve 10. When the vane moves in a clockwise direction, liquid is transformed from one side to the other through a passage 29 in the partition 5, an intermediate chamber 23 in the partition, a further passage 30, a one-way valve 31, and a final passage 24 adjacent to the cylindrical casing 3. During movement in an anticlockwise direction, the ball valve 31 is closed and liquid can only flow from one side to the other of the partition 5 through the passage 24 and the port 25 past the slide valve 27b to the intermediate chamber 23. The area of the opening is regulated automatically by adjustment of the slide valve in accordance with changes of temperature, this control being effected by a bi-metallic strip 36 contained in the intermediate chamber 23 and fixed at one end 37 to the partition 5. The other end of the strip is bent round and engages the screwed end of the spindle 27 on which the piston is mounted. The ends of the strip 36 are sprung together slightly when they are tapped so that when in position on the spindle they tend to spring apart and serve to lock the two together frictionally. Adjustment of the piston relatively to the thermostatic control is effected by rotation of the spindle 27 by a key applied through an opening in the block which is normally closed by a screwed plug 34. Liquid leaking along the bearing of the spindle is retained by a groove 54 which communicates through an inclined port with the intermediate space 23 in the partition 5. The vane 41, Fig. 4, is formed by a bent steel strip, the ends of which enter holes in the enlarged inner end 38a of the spindle 38. The strip is held in position by a doubly tapered plug 44 and a central pin 42 which is driven tightly into the spindle. The plug 44 engages both the spindle and the outer part of the strip 41. In a modification, Fig. 10, the bi-metallic strip 56 is bent round and engages with some freedom of movement a connection 57 on the side of the intermediate chamber 23 in the partition. The other end of the strip engages the screwed end of the spindle 27, a helical spring 58 being interposed between it and the piston 27b.