Vehicle-mounted drilling rig and mast lifting sliding mechanism thereof

The invention discloses a vehicle-mounted drilling rig and a mast lifting sliding mechanism thereof. The mast lifting sliding mechanism comprises a mast lifting oil cylinder with one end connected with a chassis of the vehicle-mounted drilling rig and further comprises a sliding frame. One side of the sliding frame is connected with the other end of the mast lifting oil cylinder, and the other side of the sliding frame is provided with a sliding mechanism used for being in sliding fit with a mast of the vehicle-mounted drilling rig in the length direction. The mast lifting sliding mechanism further comprises a driving mechanism for driving the mast to slide relative to the sliding frame. According to the mast lifting sliding mechanism, the adjustment of ground clearance of a drilling platform and a well control device can be achieved only by controlling the driving mechanism, the stroke of a ground supporting oil cylinder of the chassis and a ground supporting oil cylinder of the mast does not need to be increased, and accordingly the production cost of the ground supporting oil cylinders is greatly reduced. In addition, when the driving mechanism drives the mast to move up and down relative to the sliding frame, force on the mast in the vertical direction is completely born by the ground supporting oil cylinder of the mast and directly transmitted to the ground, the chassis is protected, and the damage to the chassis caused by the fact that the chassis bears an extra large load of reacting force is avoided.