Liquid injection type reamer bit

A liquid injection type bit reamer for a mine, comprising a drilling and reaming rod, a drilling tool and reaming tools, wherein a center line of the drilling and reaming rod is arranged along a front and rear direction;

• a cylindrical high-pressure water cavity with an open front end is coaxially formed in a front end of the drilling and reaming rod;
• a water injection hole is formed in the drilling and reaming rod along the direction of the center line;
• the front end of the water injection hole is communicated with the high-pressure water cavity;
• a rear end of the drilling tool is slidably connected in the high-pressure water cavity;
• a plurality of reaming tools are uniformly arranged along a circumferential direction of a front end face of the drilling and reaming rod;
• and front inner sides of the reaming tools are in jacking and pressing fit with a conical surface of the drilling tool;
• the drilling tool is of a conical structure with thick front and thin rear;
• a plurality of first diamond tool bits are uniformly arranged on a front end face of the drilling tool;
• a water through hole is formed inside the drilling tool along the vertical direction;
• a sliding seat slidably connected to an inner wall of the high-pressure water cavity is arranged at the rear end of the drilling tool;
• a spline groove is formed in the inner wall of the high-pressure water cavity along the axial direction;
• splines slidably fitted with the spline groove are uniformly arranged on the outer circumference of the sliding seat;
• and an annular retaining ring for limiting the position of the sliding seat is fixedly arranged in the front of the inner wall of the high-pressure water cavity;
• a plurality of second diamond tool bits are uniformly arranged on the inner side faces of the reaming tools;
• the front end of each reaming tool is hinged to the front end of the drilling and reaming rod through a pin shaft;
• the pin shaft is parallel to the tangential direction of the drilling and reaming rod;
• a bump located between each reaming tool and the drilling tool is arranged inside the rear end of each reaming tool;
• a diamond wear-resistant layer is arranged inside each bump;
• an extension spring is arranged between the rear side of each bump and the annular retaining ring;
• and the diamond wear-resistant layer inside each bump is in jacking and pressing fit with the conical surface of the drilling tool through a hinge point of the pin shaft under the action of the extension spring.