YOKE AS 8Y0807 - Caterpillar

Illustration 1 g00358930
The hydraulic and steering pump is a two-section vane pump. The hydraulic and steering pump draws oil from the hydraulic oil tank.Section (1) of the hydraulic and steering pump supplies oil to the steering valve.Section (2) of the hydraulic and steering pump supplies oil to the implement valve.Note: The large section and the small section of the hydraulic and steering pump operate similarly. An explanation of the operation of a typical vane pump follows.
Illustration 2 g00275070
Schematic of the Carriage Assembly for a Typical Vane Pump (6) Rotor. (7) Cam ring. (8) Outlet. (9) Passage. (10) Inlet. (11) Inlet. (12) Outlet. (13) Vane.Callouts (A) through (G) are the various locations of the vanes. (AA) Pressure oil. (BB) Supply oil.The components of the carriage assembly for a typical vane pump include a plate, an adapter, seal packs, rotor (6) , cam ring (7) and vanes (13) .Vanes (13) are pushed outward by centrifugal force. Pressure oil in passages (9) keeps the vanes pushed outward along the contour of cam ring (7) . 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 (6) turns clockwise, the vanes in positions (G) and (F) move 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 (11) . The oil fills the space between positions (F) and (A) .Oil between the vanes at positions (F) and (E) will be trapped when the vanes pass the end of inlet (11) . As rotor (6) continues to turn, the vanes are pushed inward by the contour of cam ring (7) . The chamber area between the vanes now decreases. The pressure of the oil increases.Pressurized oil between the vanes at positions (A) and (B) is pushed into outlet (8) . The oil continues to be pushed through the outlet between positions (B) and (C) . When the vane at position (B) passes the end of outlet (8) , the cycle is complete.Note: The oil that enters through inlet (10) flows through the cartridge assembly and through outlet (12) similarly.