Patent GB-466190-A (GB)
Title: Improvements in or relating to pressure or temperature operated signalling devices
IPC: F01M1/20
Filed: 1935-11-21
Abstract: 466,190. Valves. TAYLOR, A. E. and TAYLOR, J. L. Nov. 21, 1935, No. 32242. [Class 135] [Also in Groups XIII, XXIV, and XXVI] An alarm and/or cut-out apparatus operated by fluid pressure or electrically and controlled by a pressure or temperature-sensitive member movable in accordance with changes in the pressure or temperature of the cooling water and/or lubricating system of a power unit or machine has the control valves or switches held in position by release catches operated by levers with knee-joints to facilitate resetting. In the form shown in the Figure two similar ball valves, one controlling the supply of compressed air to an alarm whistle, the other controlling the supply of compressed air to means for shutting down the engine, are normally retained in the closed position by pivoted catches 50, 51 having knife edges 52, 53 engaging knife edges 54 on members 56 pivoted on a common shaft 58 and engaging heads 41 on the valve-actuating spindles 40. The catches are coupled to a releasing member 46 by springs 60 and have adjustable tappets engaging lugs on the member 46. The member 46 is held in the raised position against the action of a spring 66 by lubricating oil or cooling water pressure admitted through a port 17a to act on a diaphragm 18. When the pressure falls the lugs 62 positively release the catches but when the pressure rises again the knife edges 52, 53 engage the front faces of the edges 54, the springs 60 permitting the members 46 to move to their normal position. To reset the valves the members 56 are depressed by hand compressing the springs 42 and causing the catches to snap into engagement. The valves 25 are loaded by light springs 28 and are moved away from their seats by sliding members 35 having wedge surfaces engaged by balls movable in a cage integral with the valve seat. The valve actuating spindle carries a box-like member 39 having an internal conical flange engaging the balls so that when the catches are released the spring 42 moves the box 39 upwards causing the balls to pass through the cage and press the member 35 downwards to open the valve. A modification is, described in which two devices as described above but controlling whistles alone, are mounted on a single bracket and are controlled one by the pressure of the lubricating oil, the other by the pressure of the cooling water. The members 56 may have resetting fingers extending to the outside of protecting casings and may carry usual indicators. In a further modification three devices subject to the lubricating oil pressure, fresh cooling water pressure and salt cooling water pressure and a manually operated cock are coupled through a manifold, provided with a series of loose ball non-return valves, with a power cylinder linked to the operating arm of a fuel valve located between the low pressure fuel pump and the high pressure fuel injection pump. An automatically operating locking catch may secure the valve in its closed position. The power cylinder may be operatively connected to the governor of the power unit or may act directly on the fuel pumps to limit or stop the supply of fuel by lifting the suction valves or varying the stroke of the pump plungers. The apparatus may be modified so as to release with abnormally high pressure, or may be controlled by temperature. The member 56 may be arranged to operate an electric switch controlling an electric horn or an electric solenoid unit connected to the control mechanism of the power unit, such as an internal combustion engine. The control device may be connected to two pressure systems through a shuttle valve so that the device is actuated by the system in which the lower pressure is operative.