Patent GB-513707-A (GB)
Title: Improvements relating to lubricating apparatus
IPC: F16N27/00
Filed: 1938-04-14
Abstract: 513,707. Force-feed lubricators. TECALEMIT. Ltd. April 14, 1938, No. 11578. Convention date, April 17, 1937. [Class 12 (iii)] Lubricating apparatus comprises a pump 1 for supplying lubricant under pressure to one or more injectors 61 each leading to one or more bearings, and a pressure relief device 35. The ejector 61, Fig. 6, has a piston 77 slidable in a cylinder 69, the upper end of the piston being of larger diameter than the lower end 79. A duct 87 leads from an inlet 63 to the lower end 79 of the piston, and a duct 75 connects the space above the piston with ducts 91,93. The duct 91 leads to the inlet 63 and the duct 93 leads through a pipe 65 to a bearing. A valve 95 biassed by a spring 99 controls the opening and closing of the ducts 91, 93 with the duct 75. An exposed pin 103 on the valve 95, and a member 107 associated with the piston 77 indicate the satisfactory operation of the system. In a modification the stroke of the piston 77 is adjustable, and the member 107 is omitted. The relief device 35 consists of a valve 43 held in closed position by a spring 49 and have a tell-tale 51. The valve inlet duct 47 from the lubricant pipe 39 is small compared with the valve diameter so that once the valve opens under lubricant pressure it remains open until the pressure in the pipe 39 has fallen by a considerable amount. When the valve is open, the pipe 39 is open to a bye-pass pipe 37 leading back to the pump 1. A valve 57 connects the pipes 37, 39. The system also includes a strainer 21 comprising a casing 29, and a removable member 23 having a central aperture 25 and ribs 27 having small clearance with the casing 29. The apparatus works as follows :- Upon operation of the pump 1, oil passes through the strainer 21 to the line 39, the valve 57 being closed. The oil pressure moves the valve 95 from the position shown in Fig. 6 to a position which closes the duct 91 and opens the duct 93. Oil also passes through the duct 87 and forces the piston 77 upwardly to eject oil above the piston through ducts 75, 93, to the bearings. Any other injectors 61 in the system are actuated similarly. Pumping is continued until the relief valve 43 is opened to cause reduction of pressure in the pipe 39. Before the relief valve 43 closes the valve 95 returns to the position shown in Fig. 6, and the piston 77 drops to recharge the top part of the cylinder 69. The valve 57, which opens after the valve 43, remains open after the valve 43 has shut to ensure that all the injectors have been recharged. The connection between the pumping means and the pipe lines 37, 39 may be detachable, or a single pumping means may be used in connection with a series of pump lines 39. An automatic system is shown in Fig. 8. The pump is driven by a motor 125 the circuit of which includes a time switch 129 and a pressure switch 131. A power circuit 133 energises a circuit 135 having a signal lamp 137 and contacts 139 in series. The contacts 139 are closed by the members 107 of the injectors 61 when the latter have been actuated. Upon actuation of the relief means 35 a surge of pressure is passed to the pressure switch 131 to open the circuit 127, and the motor is shut off until the time switch 129 again closes the circuit 127. U.S.A. Specifications 1,893,464, 1,902,750, 1,963,783 and 2,019,299 are referred to.