Reaming and self-rotating anchor rod and using method thereof

A reaming and self-rotating anchor rod, comprising:

• a rod body, wherein the rod body has threads without longitudinal rib on an external surface and the rod body including an anchoring device and a connecting part in a symmetric wedge on a front and rear of a tail part respectively;
• a drill bit, wherein the drill bit is arranged at a head part of the rod body;
• the head part of the rod body connected with the drill bit via a plurality of threads, wherein a pitch of the drill bit is identical to a pitch of the threads without longitudinal rib;
• a connecting member on the connecting part to facilitate a connection to an anchor rod bolter, an end of the connecting member connected to the rod body is a cylinder with an inverted wedge-shaped cut therein, which matches the symmetric wedge at the tail part of the anchor rod body;
• wherein, the rod body, the drill bit and the connecting member are interconnected through a threaded connection into a combined structure, and
• a tray and a nut;
• wherein when the rod body penetrates into a coal seam, the tray is fitted over the tail part of the rod body and is fixed by the nut;
• wherein an out diameter of the drill bit is greater than a diameter of the anchor rod body by 3˜8 mm,
• wherein the drill bit has an opening connected with the anchor rod body and a plurality of sharp knives that protrude and incline toward a center of the drill bit are arranged around the opening, a top of each sharp knife being between 3 mm and 5 mm from the center of the drill bit including spiral grooves configured to discharge slack coal produced during drilling from the drill bit are arranged on a side surface of the drill bit, wherein the spiral grooves are in 5 mm˜8 mm width and 3 mm˜5=depth;
• wherein a plurality of baffle pawls are arranged at a clearance between the grooves on the side surface of the drill bit, and each baffle pawl comprises:
• a high-strength baffle plate,
• a groove cavity, the groove cavity provides a space for rotation of the high-strength baffle plate,
• a circular shaft, one side of a bottom of the groove cavity is movably connected with the high-strength baffle plate via the circular shaft, and
• a strong spring, the strong spring being arranged between the high-strength baffle plate and the bottom of the groove cavity, the high-strength baffle plate is ejected by the strong spring and can rotate within the groove cavity via the circular shaft;
• wherein the symmetric wedge at the tail part of the rod body has a length between 30 mm and 100 mm, and an opening angle of the symmetric wedge is between 55° and 75°;
• wherein the rod body has an annular protrusion welded to the rod body between ⅓ and ⅔ length of the rod body, a diameter of the annular protrusion is greater than a diameter of the rod body by 3 mm˜8 mm, and a thickness of the annular protrusion is between 2 mm and 3 mm.