GB727239A - A new or improved fluid-flow reversing device - Google Patents

Abstract

727,239. Lubricating. EXACTOR, Ltd. Oct. 17, 1952 [Oct. 19, 1951], No. 24501/51. Class 12 (3) [Also in Group XXIX] A fluid flow reversing device, for use for example in lubricating systems, of the kind comprising a housing having means for connection to a pressure supply and to the two ends of a closed external circuit and three shuttle valves operable in three independent bores with closed ends in the housing, one valve, a pilot valve, being operable by return flow of fluid from the external circuit to change the supply pressure from one end to the other of the second valve, the main valve, thereby causing the main valve to change the supply pressure from one end to the other of the third valve to cause it to reverse the direction of flow through the external circuit, is characterized in that the three bores for the valves are parallel, and the housing is in two parts in face-to-face pressure tight relation, and passageways between the bores are in part formed by grooves provided in the mating face of one of the body parts. In the arrangement shown, a housing is in two parts secured face-to-face by screws, a part 1 being provided with a cylindrical bore 4 fitted with a main valve 5 and a part 2 having two cylindrical bores 12, 13 fitted respectively with a pilot valve 14 and a diverter valve 15. The valve 5 has an indicator 6. The housing has an inlet 31 for grease supplied by a pump, two outlets 32, 33 leading to the two ends of an external circuit containing one or more dispensing devices 41, and an exhaust outlet 34 which may be connected back to the grease reservoir. Internal passageways in the housing connect the conduits as necessary. With the valves in the position shown in Fig. 11, grease passes through inlet 31, passageways 102 and 111 to the outlet 32 and devices 41 are operated in succession. The return flow passes around the stem of the diverter valve 15 to passageway 110 and thence to one end of bore 12, causing the pilot valve 14 to move to the right, the grease at the other end of bore 12 passing to exhaust 34 through'passageway 109. The movement of the pilot valve cuts off pressure from the supply to the left of main valve 5 and applies it to the right of this valve through passageways 104, 106. The main valve is thus moved to the left, whereby inlet 31 is disconnected from passageway 102 and is connected to passageway 103. The diverter valve is then moved to the right causing the passageway 103 to be connected to the outlet 33 so that the grease begins to flow in the reverse direction in the external circuit. This initiates the return movements of the valves 14, 5 and 15.