GB543618A - Improvements in and relating to piston pumps - Google Patents

Abstract

543,618. Piston -pumps ; motor vehicles. BROMILOW & EDWARDS, Ltd., and SWIFT, H.W. Sept. 5, 1940, No. 13901. [Class 102 (i)] [Also in Group XXXI] A piston pump for hydraulic tipping gear and like discharging equipment on vehicles comprises a pump casing 1 directly attached by bolts 8 to the gear box 10 or auxiliary power takeoff extension 9 of the vehicle, the pump shaft 4 being directly coupled to the power take-off without intermediate shafting. The eccentrics 24 on the shaft are encircled by straps 23 the connecting rods 19, 20, 21 of which are pivotally connected by gudgeon pins 22 to pistons 16, 17, 18 which operate in liners 25 shrunk into parallel bores 13, 14, 15 in a cylinder block 12. The latter is formed with delivery ports 26, 27, 28 co-axial with the bores 13, 14, 15 and communicating with a duct 36 by spring-urged mushroom or poppet valves 40 bearing on ring valve seats 41. The cylinder block is also formed with inclined inlet ports 29, 30, 31 in a lateral projection 32 and communicating with a duct 33 by valves 34 similar to the valves 40 and bearing on ring valve seats 35. Each of these valves comprises a spindle 42 slidable in a bush 43 on flanged screwed-in plugs 44, a spring 45 being interposed between the valve and a socket 46 on the plug. The cylinder block 12 also includes a combined overload, lowering, and relief poppet valve 51 which controls a passage 52 joining the delivery duct 36 to the inlet duct 33. The valve 51 is controlled by an adjustable spring 57 against which it is operated by a lowering lever 55. A blank end cover 60 with an oil seal 61 for the projecting portion 11 of the shaft 4 is provided for attachement to the pump when it is not secured to the gear box. Specifications 500,232, [Group XXXII], and 543,619 are referred to.