GB437108A - Improvements in means for inflating pneumatic tyres - Google Patents

Abstract

437,108. Pressure-regulating valves. TECALEMIT, Ltd., and CHALMERS, R. A., Great West Road, Brentford, Middlesex. April 19, 1934, No. 11814. [Class 135] Apparatus for inflating or deflating pneumatic tyres comprises a pressure control unit 1 with a valve 10 which regulates the air pressure from a supply pipe 23 through pipes 24, 40 to a chamber 37 between two diaphragms 34, 35 of a delivery control unit 32. Attached to one of the diaphragms 34 is a valve 52 which controls the air supply from the pipe 55 to the tyre through the pipe 47 until the tyre pressure on one side of the diaphragm 34 equals the regulated pressure in the chamber 37 on the other side, when the valve 52 will close. Attached to the other diaphragm 35 is a release valve 48 so that should the tyre pressure on the outside of the diaphragm 35 be higher than the required pressure in the chamber 37 the valve 48 will open to atmosphere to release the tyre pressure until it equals that in the chamber 37. The pressure in the diaphragm chamber 37 and hence the tyre pressure is determined by the adjustment of the spring loading 20 on a piston 18, which controls the valve 10 and which is subjected to the regulated pressure, by a manually operated cam 26 with a lever 28. The piston 18 is sealed by a diaphragm 15 and has an axial relief passage which is controlled by a valve 11 on the stem of the valve 10 so that if the regulated pressure on the diaphragm 15 is too high the piston moves away from the valve 11 and releases some of the air to atmosphere until the required pressure is obtained. A gauge 57 is provided to normally indicate the required pressure in the chamber 37 but may be connected by means of a valve 58 and a conduit 68 directly to the tyre.