Height-adjustable workbench for vertical drilling machine

The utility model relates to the technical field of drilling machine workbenches, and discloses a height-adjustable workbench for a vertical drilling machine, the height-adjustable workbench comprises a bottom plate and a supporting plate, the middle part of the top end of the bottom plate is fixedly connected with a concentric-square-shaped frame, the middle part of the bottom end of the supporting plate is fixedly connected with a square rod, and an internal thread cylinder is fixedly embedded in a through hole formed in the middle part of the bottom end of the square rod; a threaded rod is inserted into the inner threaded cylinder in a threaded mode. One end of the inner bottom wall of the concentric-square-shaped frame is fixedly connected with a low-speed motor, the end of an output shaft of the low-speed motor is fixedly sleeved with a first bevel gear ring, and the bottom end of the threaded rod is fixedly sleeved with a second bevel gear ring. According to the scheme, an output shaft of a low-speed mo