Patent GB-715104-A (GB)
Title: Fluid pressure systems especially for lubricants
IPC: F16N13/22
Filed: 1952-05-26
Abstract: 715,104. Valves. FARVAL CORPORATION. May 26, 1952 [April 3, 1952], No. 13301/52. Class 135. [Also in Group XXXIV] In a fluid-pressure system, suitable for use in delivering lubricant to bearings &c. at timed intervals, two separate conduits are adapted to receive liquid under pressure fed from a reservoir by two pump means, and valve means are provided operative alternately to bleed the discharge of one of said pump means to reservoir whilst also connecting the other end of the conduit fed by such latter pump means to reservoir, so that the conduits may be alternately subjected to pressure and relieved of pressure. In the arrangement shown in Fig. 1, a pumping unit 1 having a lubricant reservoir 2 connected therewith, is driven by an electric motor 3 through a pulley 4, V-belt 5 and pulley 6. Supply lines 7, 8 lead from the unit 1 to lubricant measuring valves 9 and back to the unit. When the line 7 is under pressure lubricant will enter valve cylinder 10 in a valve 9 and will move valve member 11 to the position shown, admitting lubricant to the lower end of the measuring cylinder 12. Piston 13 is thereupon moved to expel a measured charge of lubricant through outlet 14 to the part to be lubricated. A timer 15 may be connected with the motor 3 and with limit switches 20, 21 whereby the lubricating system is initiated and shut down as required. Other means as for example manual control or' the use of an automatically-controlled magnetic clutch coupling between pulley 6 and its driven shaft, may be used to control the system. The pumping unit 1 and reservoir 2 comprises a frame 24, Figs. 6 and 7 to house the limit switches and a control valve block 30 attached to a pump housing 29, above which the reservoir 2 is mounted. The pump drive shaft 33 has at its inner end an eccentric driving stud 35 engaging a vertical slot 36 in the head 37 of a doubleacting pump piston the end 38 and 39 of which reciprocate in cylinders 40, 41. As the end 39 reciprocates it covers and uncovers inlet port 43 thereby forcing lubricant past a check valve 45 into valve chamber 47 which is connected by an annular passage 49 to the supply line 7. Member 47 is also connected to a passage 55 which leads to a cylinder 56 in which a control piston 57 is mounted for reciprocation. The passage 55 is shown communicating by way of passages 72, 73 and 74 with the reservoir 2 for lubricant, so that the outlet end of the supply line 7 is relieved of pressure. The return end of the supply line is connected to the valve block 30 through passage 76 which is also in communication with the 'reservoir 2 so that the supply line 7 is relieved of pressure at both ends. Lubricant pumped' into valve chamber 46 passes through an annular passage 48 to. supply line 8 and is eventually delivered through the valves 9 to the parts to be lubricated. Excess lubricant returns to passage 90 and flows through passages 91, 78, 80 and 82, to the lower end of an accumulator cylinder in which a spring is compressed by the pressure of the lubricant. The pressure of lubricant in the line 8 eventually is high enough to move the control piston 57 to the right against the action of a spring 64. This spring has a toggle action which keeps in one or other of two extreme positions a lever 63 formed at its inner end with teeth engaging a rack portion of the piston 57. The lever 63 is thus thrown over, causing limit switch 20, Fig. 1, to close and allowing limit switch 21 to open. The movement of the piston 57 to the right cuts off return of lubricant from line 7 to the reservoir, and connects line 8 to the reservoir. The operation of the limit switches opens the circuit of the motor, which does not start until the timer 15 has opened contacts 22 and closed. contacts 23, whereupon lubricant is supplied through the supply line 7. The piston 57 may have protruding indicator stems on the ends to show operation of the mechanism. Specification 701,722 is referred to.