GB834533A - Improvements in and relating to the lubrication of internal combustion engines - Google Patents

Abstract

834,533. Lubricating. KYLE, D. W. E. Jan. 24, 1956 [Feb. 4, 1955; Oct. 11, 1956], Nos. 3423/55 and 29000/55. Class 12 (3). A method of lubricating the working cylinder of an internal combustion engine comprises injecting lubricant into the cylinder at a position a little below the head of the piston at substantially the end of the compression stroke under a pressure exceeding the pressure in the cylinder. The lubricant may be injected into the cylinder by at least one pump actuated by fluid pressure available on the engine but high enough to enable the lubricant to be injected at a pressure higher than the compression pressure in the working cylinder. The fluid pressure may be the pressure of the fuel supply to the fuel injection nozzle. In the apparatus shown in Fig. 1, a piston 11 works in a cylinder 12 to which either fuel under pressure or air from the head of the working cylinder is admitted. A crosshead 13 extends over plungers 14 mounted in a block 16 and working in bores 15 as lubricant delivery pumps. Aligned with the bores 15 are bores 17 containing plungers 18 which form parts of metering pumps. The delivery stroke of these pumps is effected by a platen 19 connected to the crosshead 13, the platen carrying forward the plungers 18. The suction stroke of the plungers may be varied by means of flanges 22 on sleeves 23 screwing into the block 16 and co-operating with collars 24 on the plungers 18. The springs 231 effect the suction stroke to cause lubricant to be drawn through sight glasses 33 and pipes 32 and past valves 25 into the bores 17, from which lubricant is drawn, past valves 26, on the suction stroke of the plungers 14 to be delivered past valves 27 and through delivery pipes 31 leading to points in the working cylinder. The sight glasses 33 are supplied with lubricant from a reservoir 34 in which the lubricant is kept at a constant level by a float valve 35. In the construction shown in Fig. 2, a number of pumps are arranged in the base of a container 41 for lubricant. Along the front is a bar 42 with a passage 43 connected with the fuel supply leading to the injector of the associated working cylinder. The fuel has access to a row of pistons 44 which through tappets 45 act upon metering pump plungers 46. Each plunger acts against the plunger 53 of a lubricant-delivery pump provided with a spring- pressed delivery valve 54. The metering pump draws lubricant from the bottom of the container 41 by uncovering a port 79, the lubricant passing a ball valve 65 and through a port 81 and passage 82 to the upper end of a sight feed glass 47 in which an air cushion is trapped. The outlet from the feed glass leads through passage 55 to a port 78 which is uncovered upon return movement of the delivery pump plunger 53. Forward movement of the plunger forces the lubricant past the valve 54 and out through pipe 77 to the working cylinder. A lever 56 may be provided for each metering pump to enable it to be operated independently of the fuel plunger.