| 摘要 |
1281935 Reciprocating pumps NORTH AMERICAN ROCKWELL CORP 5 Nov 1969 [5 Nov 1968] 54175/69 Heading F1A [Also in Division B6 In a rotating cylinder variable displacement swash-plate pump, a linkage controlling the inclination of the swash-plate is arranged such that it may be varied during operation, or, if the plate is immovable during stoppage, pre-set so that on re-starting assumes the pre-set inclination. The linkage comprises an adjusting cam 42 and an L-shaped member 43 pivoted at 44, an arm 46 of which is biased against the cam by a spring 48 fixed to a frame carrying the pump. The swashplate 31 is biased to maximum displacement by a spring 52 also fixed to the frame, and a pin 32 on the plate thus biased to the other arm 47 of member 43. On rotation of the cam to raise arm 46, with the plate 31 immovable, a gap is created between pin 32 and arm 47; opposite rotation creates a gap between the cam and arm 46. On starting the pump the springs act to close the gaps, spring 48 being the stronger, and thus vary the stroke. In another embodiment, Fig.9, a swashplate (61), Fig.8 (not shown) carries an extension 78 and is biased as before to maximum displacement by a spring (52); the linkage comprises a disc 66 having a pin 67 and two levers 63, 62 rigidly connected. A spring 80 between lever 62 and the swash-plate biases lever 62 against extension 78. Rotation of disc 66 in one direction, whilst the plate is fixed, opens a gap between lever 62 and extension 78, spring 80 being compressed; opposite rotation opens a gap between lever 63 and 67. On starting the pump the springs act to close the gaps, spring 80 being the stronger. In a further embodiment, Fig.11, a swash-plate 91 is controlled by a lever 92 whose position is varied by a rotatable disc 93 and pin 116. This disc is pinned at 96 to a disc 95 carrying a pin 110, a helical spring 112 between the discs biasing the pin 110 against a shoulder 111 on disc 93 and a spring 90, attached to lever 92 and the frame, biases lever 92 against pin 116. With the swash-plate fixed, disc 95 may be rotated to open gaps between pin 110 and shoulder 111, or between lever 92 and pin 116; these gaps are closed on re-starting the pump by springs 112 and 90, spring 112 being the stronger. A number of pumps may be supported within the frame, each cylinder block 12, Fig.5, carrying gearing 15 for driving the pumps. On rotation each pumping chamber is alternatively connected with inlet and outlet passages in a stub shaft 13 supporting the block, Figs.2, 3 and 4 (not shown). |
