GASKET 1397957 - Caterpillar

Illustration 3 g06098482
Propulsion Pump Cross Section - Travel Mode
(39) POR valve
(44) Feedback linkage
(45) Orifice
(46) Direction control valve
(47) Servo piston
(48) Input shaft
(49) Swashplate
(50) Slipper pads
(51) Piston
(52) Barrel assembly
(53) Port plateNote: The above illustration shows a typical example of the propulsion pumps. The components in the pump are representative of the propulsion pumps on this machine. However, the pump housing and relief valve locations on the propulsion pumps may differ slightly from the illustration.Engine rotation turns input shaft (48). The input shaft then rotates barrel assembly (52). Pistons (51) rotate with the barrel assembly. Piston slipper pads (50) allow the pistons to follow angle of swashplate (49). The pump only generates flow when the swashplate is not at zero angle.Direction control valve (46) is equipped with two proportional solenoids. The proportional solenoids control forward and reverse operation of the propulsion pump.As input shaft (48) rotates, slipper pads (50) follow angle of swashplate (49). In this case, the pistons move in and out of barrel assembly (52). As a piston moves out of the barrel assembly, oil in the low-pressure circuit is drawn into the piston chamber. As a piston moves into the barrel assembly, oil is forced out of the piston chamber and into the high-pressure circuit.As the load on the propulsion system increases, increased pressure in the system tends to move swashplate (49) toward the neutral position. The swashplate movement causes feedback linkage (44) to reposition the