Built-in hydraulic distributor

The invention discloses a built-in hydraulic distributor which comprises a distributor shell and a main control valve, an oil return valve and a check valve which are arranged in the shell; an oil inlet, an oil cylinder oil inlet and an oil return opening are formed in the distributor shell; a lowering valve is arranged in a main control valve hole; a lowering valve compressing sleeve and a lowering valve adjusting bolt are arranged at the right side of the lowering valve; the lowering valve is arranged at the right side of the main control valve; the oil cylinder oil inlet communicates with the oil inlet chamber of the lowering valve by an oil cylinder oil drainage oil line; the oil outlet chamber of the lowering valve communicates with the oil return opening; the lowering valve comprises a lowering valve core and a lowering valve seat; the lowering valve compressing sleeve compresses the lowering valve seat; and the lowering valve adjusting bolt compresses on the lowering valve compressing sleeve. The built-in hydraulic distributor can improve the lowering and lifting sensitivity, and the hydrostatic sedimentation value of a hydraulic lifter is ensured by the sealing state of the lowering valve and the check valve, thus being more reliable, good in airtightness, steady in use performances, high in reliability, and convenient to dismantling and maintenance.