Drills are used to drill through holes or blind holes on solid materials, and can enlarge existing holes. The commonly used bits are twist drill, flat drill, center drill, deep hole drill and casing drill. Although reamer and spot facer can't drill on solid material, they are also used to be classified as drills.
When digging, the drill rotates with the vertical axis and moves axially at the same time. The soil is cut under the action of the torque and axial force of the bit, and it is broken under the action of the extrusion and centrifugal force of the working blade, forming the soil flow pressure to the pit wall, and at the same time, it is lifted to the surface along the page. When the soil flow moves to the place where there is no pit wall obstruction, due to the centrifugal force, the crushed soil is thrown around the pit to complete the excavation process.
A drill bit comprises a cutter rod (1), a cutter rod having a tip, and two cutting blades (5, 5 ') on a main plane (C-C), said cutting blades (5, 5') having short center cutting blades oriented on a common second plane (E-E). The cutting edge forms a point shaped central cutting edge for entering the workpiece, and thereby centers the drill bit. In knife
Two chip removal grooves (6,6 ') are arranged on the rod, and the chip removal grooves (6,6') extend from the tip to the bottom end. On any section along the cutter bar, the chip removal grooves are located in the positions radially opposite each other on the tube plane, the tube plane extends 90 ° with the common cutting edge plane (f-f) of the two cutting edge bands on both sides of the tube, and the cutter bar has the maximum rigidity in the plane. The orientation of the second plane (E-E) of the center cutting edge is about 90 ° to the main rigid direction (f-f) of the plane of the edge belt or the bottom end of the tool bar.
The utility model relates to a drill bit which can ease the sudden change of drilling state in the drilling operation of concrete and so on, and make the drilling operation stable, and the drilling efficiency will not be reduced even when large chips are produced.
The cutting edge which is roughly radially arranged has at least two main cutting edges and at least two auxiliary cutting edges which are arranged between the main cutting edge and the main cutting edge in the circumferential direction. The main cutting edge has a main cutting edge as its cutting edge, the inner end of the main cutting edge is at the rotation center, and the outer end is at the outer edge of the rotation track of the cutting edge.
The sub cutting edge part has a sub cutting edge as its cutting edge, the inner end of the sub cutting edge is located at the position that the outer radial side deviates from the rotation center, and the outer end is located at the position that the outer edge deviates from the rotation path of the cutting edge part towards the rotation center side.
A drill bit is provided with a plurality of cutting edge parts arranged at the front end of the drill bit, an axial drill body arranged at one side of the base end of the cutting edge part and formed with a handle on the base end;
The cutting edge part is provided with a cutting edge formed by protruding the front end side of the joint edge of the cutting surface and the back clearance surface, and the cutting edge is configured in a roughly radial shape from the outer diameter side of the rotation center of the drill bit;
The utility model uses the compound action of the rotation action and the action in the axial direction to carry out impact cutting, which is characterized in that the cutting edge part has at least two main cutting edge parts, and at least two auxiliary cutting edge parts which are arranged between the main cutting edge part and the main cutting edge part in the circumferential direction;
The main cutting edge has a main cutting edge as its cutting edge, the inner end of the main cutting edge is at the rotation center, the outer end is at the outer edge of the rotation path of the cutting edge, the sub cutting edge has a sub cutting edge as its cutting edge, the inner end of the sub cutting edge is at the position deviating from the rotation center to the radial side, and the outer end is at the position deviating from the outer edge of the rotation path of the cutting edge to the rotation center side Location