Crotch type base of hydraulic support for coal mines

The invention discloses a crotch type base of a hydraulic support for coal mines. The crotch type base comprises a crotch type base body, a pushing rod arranged at the crotch position of the crotch type base along the longitudinal direction and two bottom lifting devices arranged on the crotch type base. The two bottom lifting devices are arranged at the front portion of the crotch type base and symmetrical to the longitudinal central line of the crotch type base. Each bottom lifting device comprises a bottom lifting jack, wherein a piston rod of the bottom lifting jack is upwards arranged in box-shaped cavities of the crotch type base, the top end of the piston rod of the bottom lifting jack is hinged to a positioning seat fixed on the crotch type base, and a lug plate is fixedly connected to the lateral wall of a cylinder body of the bottom lifting jack and extends to the crotch position of the crotch type base to be fixedly connected with a wear-resisting block positioned above the pushing rod. The crotch