Hydraulic transaxle apparatus for a four-wheel driving vehicle and four-wheel driving vehicle using the apparatus

A transaxle apparatus, comprising:

• a housing;
• a hydrostatic transmission disposed in said housing, said hydrostatic transmission including a hydraulic pump receiving power from a prime mover, a hydraulic motor driven in response to fluid supplied from said hydraulic pump, and a center section, wherein said center section includes an inner fluid passage for fluidly connecting said hydraulic motor to said hydraulic pump, and a port disposed in a surface of said housing and fluidly connected to said inner fluid passage for supplying hydraulic fluid flowing in said inner fluid passage to another hydraulic motor disposed outside of said housing for driving an axle outside of said housing;
• and
• an axle disposed in said housing and driven by said hydraulic motor in said housing.

A vehicle, comprising:

• a first frame disposed at either a front or a rear portion of said vehicle, said first frame having a proximal end with respect to said vehicle:
• a prime mover mounted on said first frame;
• a first transaxle apparatus supported by said first frame, said first transaxle apparatus including an input shaft receiving power from said prime mover, a pair of first axles and a hydrostatic transmission, wherein said hydrostatic transmission includes a hydraulic pump driven by rotating said input shaft and discharging fluid variably in quantity and direction a first hydraulic motor for driving, said first axles, a fluid passage fluidly connecting said hydraulic pump to said hydraulic motor, and a port disposed in a surface of said housing and fluidly connected to said fluid passage;
• a second flame disposed at the other of said front or rear portions of said vehicle, said second frame having a distal side and a proximal end with respect to said vehicle;
• a second transaxle apparatus supported by said second frame said second transaxle apparatus including a pair of second axles having different lengths and a second hydraulic motor for driving said second axles, said second hydraulic motor fluidly connected to said port;
• a working device attached to said distal side of said second frame;
• a coupling part for coupling said proximal ends of said first and second frames to each other so that said first and second frames are rotatable around a vertical axis relative to each other according to a steering operation;
• a rotor for receiving power from said prime mover, a rotary axis of said rotor being disposed on said vertical axis;
• and
• a transmission element drivingly connecting said rotor to said working device, said transmission element crossing a larger axle of said pair of second axles.