STARTING AID GP 2427250 - Caterpillar

Illustration 1 g01095706
(1) Elevator and implement vane pumpThe elevator and implement vane pump (1) is located at the rear of the tractor in the center of the machine. Pump (1) is mounted to the side of the transfer gear case.The small section of pump (1) provides oil that is needed to operate the elevator motor in FIRST SPEED FORWARD and SECOND SPEED FORWARD. The large section of pump (1) provides oil that is needed to operate the following components: bowl cylinders, ejector cylinder, floor cylinder and elevator motor in REVERSE speed.Note: The elevator section and the implement section of pump (1) operate similarly. An explanation of the operation of a typical vane pump follows.
Illustration 2 g01095813
Schematic of the Cartridge Assembly for a Typical Vane Pump (2) Rotor (3) Cam ring (4) Outlet (5) Passage (6) Inlet (7) Inlet (8) Outlet (9) Vane (A through G) Vane positions (AA) Pressure oil (BB) Supply oilThe cartridge assembly for a typical vane pump is composed of the following components:
Plate
Adapter
Seal packs
Rotor (2)
Cam ring (3)
Vanes (9) Initially, vanes (9) are forced outward by centrifugal force. The pressure oil in passages (5) keeps the vanes (9) along the contour of cam ring (3). Both ends of the vanes are connected by these passages. The oil in these passages keeps the pressure equal on both ends of the vanes. Also, the oil behind the vanes is allowed to escape as the vanes are pushed inward.As rotor (2) turns clockwise, the vanes in positions (A) and (B) extend outward along the contour of the cam ring. As the chamber area between the vanes increases, the oil pressure drops and a vacuum is created in the chamber. This pressure difference causes oil to flow from the hydraulic oil tank and through inlet (6). The oil fills the space between positions (B) and (D) .Oil between the vanes at positions (B) and (C) will be trapped when the vanes pass the end of inlet (6). As rotor (2) continues to turn, the vanes are pushed inward by the contour of cam ring (3). The chamber area between the vanes now decreases. The pressure of the oil increases.Pressurized oil between the vanes at positions (D) and (E) is pushed into outlet (4). The oil continues to be pushed through the outlet between positions (E) and (F). When the vane at position (E) passes the end of outlet (4), the cycle is complete.Note: The oil that enters inlet (7) flows through the cartridge assembly and through outlet (8) similarly to the oil that enters inlet (6).