(3) Drain port
(4) Drain hole
(24) Front direction
|Identification Of Port And Circuit|
|Ports (Housing)||Ports (Rotor)||Circuit|
|7||18||Right travel (reverse)|
|10||21||Right travel (forward)|
|8||20||Left travel (forward)|
|5||17||Left travel (reverse)|
|11||16||Change of Travel speed|
Swivel (22) accomplishes two functions. Swivel (22) supplies pump oil from the upper structure to the travel motors of the lower structure. The upper structure swings. The lower structure does not swing. Swivel (22) returns oil from the travel motors to the hydraulic tank.
Housing (9) is restrained to the upper structure through support (23). Support (23) is used as a torque arm in order to prevent housing (9) from rotating. Rotor (14) is bolted to the lower structure through plate (15). The ports of housing (9) are open to the ports of rotor (14). The passages in housing (9) and the passages in rotor (14) connect the ports.
Seal (6) for high pressure and seal (13) for low pressure are provided between the sliding surfaces of housing (9) and rotor (14). Seals (6) and (13) prevent oil leakage between the passages.