A distribution valve for a transmission of a high-
horsepower tractor, comprising a valve body (1), and an oil inlet port (P), oil return ports (T), a
clutch oil port (F), a working
gear oil port (D), a
clutch control
spool valve (2) connected to the oil inlet port (P), a
clutch oil port (CA) communicated with the
clutch control spool valve (2), a
brake oil port (CB), a first overflow valve (R3) used for controlling the pressure of the
brake oil port (CB), and a second overflow valve (R2) used for controlling the pressure of the working
gear oil port (D) which are arranged on the valve body (1). The distribution valve further comprises a three-position three-way regulating
spool valve (R1), and the three-position three-way regulating spool valve (R1) is provided with a working oil port (A1), a spool
valve oil return port (T1), a spool
valve oil inlet port (P1), and a
hydraulic control port (K1) which is communicated with the oil inlet port (P) and connected in parallel to the spool
valve oil inlet port (P1). The present invention has the characteristics that
oil pressure is precisely controlled, and
oil can be quickly and instantly conveyed to achieve
lubrication, cooling and protection for device components, thereby reducing maintenance costs, and ensuring normal, stable, and efficient operation of the
tractor.