Long-life drill bit with downhole self-renewal capability

A long-life drill bit with a downhole self-renewal capability, comprising:

• a drill bit body and
• a joint,
• wherein a fixed blade and a support blade are arranged on the drill bit body, main cutting teeth are embedded in the fixed blade, and central flow channels are arranged inside the drill bit body and the joint, wherein a self-renewal wheel is arranged on the support blade, the self-renewal wheel is provided with self-renewal teeth, the self-renewal wheel is rotatably connected with the support blade through a wheel shaft, and one end of the self-renewal wheel is provided with a first cone wheel;
• and wherein a transmission shaft, a ratchet shaft, a spring and a sliding pin are arranged inside the drill bit body, a second cone wheel is arranged at one end of the transmission shaft and a spline groove is arranged at an other end of the transmission shaft, the second cone wheel of the transmission shaft and the first cone wheel of the self-renewal wheel are meshed with each other, an upper spline is arranged at one end of the ratchet shaft, a ratchet groove is formed in the ratchet shaft, a lower end of the ratchet shaft is provided with a pressure-bearing surface, the upper spline of the ratchet shaft and the spline groove of the transmission shaft are matched with each other, the sliding pin and the ratchet groove are in a sliding fit, the spring is arranged between the ratchet shaft and the transmission shaft, and the sliding pin is arranged between the drill bit body and the joint.