GB1095923A - Automatically reversible gear pump - Google Patents

Abstract

1,095,923. Rotary pumps. CARRIER CORPORATION. Aug. 23, 1965 [Sept. 1, 1964], No.36126/65. Heading F1F. A reversible rotary-pump of the n and n+1 lobe type for effecting lubrication of a compressor comprises an internally-lobed or toothed gear 43, Figs. 1 and 3, meshing with an externallylobed or toothed gear 45 rotatably mounted on an eccentric portion 40 of a carrier 32, which is rotatably lodged in a non-rotatable axially-movable member 25 so as to render the flow of lubricating oil unidirectional irrespective of the direction of rotation of the gears, the gear 43 being coupled to one end of a crank-shaft 7 in the compressor by a pin 44 to rotate therewith. Rotation of the carrier 32 is restricted to angle of 180‹ by a pin 35 that is attached to an axially-movable plate 24 and engages with an arcuate recess 38 in the said member. In operation, lubricating oil is drawn into working spaces between the gears from a reservoir through an opening 20 in a cover 17 and an arcuate inlet-port or passage 28 formed in the member 25, the plate 24 and a further axially-movable plate 23, which is engaged by a compression spring 19 lodged in the cover 17. Lubricating oil is ejected from the working spaces through an arcuate port or passage 29 in the member 25, an opening 34 in the plate 24 and a passage 41 in the carrier 32 communicating with lubrication passages 9, 10 in the crank-shaft 7. If the direction of rotation of the crank-shaft is reversed, the carrier 32 is rotated through an angle of 180‹ by the action of the gears to produce corresponding displacement of the gear 45 and prevent reversal of the pumping effect. Alternatively, the pump comprises an internallylobed or toothed gear 57, Fig. 4, meshing with an externally-lobed or toothed gear 58 rotatably mounted on an eccentric portion 84 of a cylindrical carrier 76, which is rotatably lodged in a non- rotatable axially-movable member 65, the gear 57 being coupled to one end of a crank-shaft 55 in the compressor by a pin 59. Rotation of the carrier 76 is restricted to an angle of 180‹ by a pin 80 attached to the member 65 and engaging with slot or recess 80 in the carrier. Recesses 70, 72 in the member 65 connect inlet and outlet ports 74, 75 to corresponding passages 50, 51 for lubricating oil in a bearing housing 53 for the crank-shaft, the outlet recess 72 being connected by a passage 77 to a chamber containing a compression spring so as to effect pressure-loading of the member 65. Rotation of the member 65 is prevented by a pin 66 engaging with a cover 64. Axial movement of the carrier 76 relative to the member 65 is prevented by a ring 79. Reversal of the direction of rotation of the crank-shaft causes rotation of the carrier 76 and displacement of the gear 58 through an angle of 180‹ to prevent reversal of the pumping action.