Twist drill with front angle correction and machining method of twist drill

Abstract

The invention discloses a twist drill with front angle correction and a machining method of the twist drill. The twist drill comprises a cutting part and a handle part; the front end of the cutting part is provided with a drill tip; the cutting part is provided with two spiral chip grooves extending from the drill tip to the handle part; the portion, between the two spiral chip grooves, of the cutting part forms a blade petal; the front end of the blade petal is provided with a main blade belt; the spiral chip grooves are connected with the main blade belt through a front angle correction face; in the section perpendicular to the cutting part, the connecting line of the front end point M of the main blade belt and the center O of the blade petal is a line N; the front angle correction face is concave inwards relative to the line N; and the front angle of the front angle correction face is gamma, and gamma is a positive acute angle. The machining method comprises the steps of rough grinding, brush fine grinding, front angle correction surface grinding and the like. According to the twist drill with front angle correction and the machining method of the twist drill, the sharpness of the twist drill is improved easily, the cutting torque of the twist drill is reduced, the risk of built-up edges generated in the drilling process is reduced, the drilling precision is greatly improved, the service life is greatly prolonged, the brush polishing process is adopted, the manufacturing cost of the twist drill can be greatly saved, and the production efficiency of the twist drill can be greatly improved.

Description

technical field [0001] The invention relates to cutting processing, in particular to a twist drill with rake angle correction and a processing method for the twist drill. Background technique [0002] Deep hole processing generally refers to hole processing with an aperture ratio greater than 5. Deep hole machining is a difficult point in drilling. During the drilling process of soft materials (such as aluminum alloy materials, etc.), machining vibrations are prone to occur, resulting in out-of-tolerance straightness and roundness of the processed holes, and even built-up edge. As a result, the cutting force increases sharply, the torque increases, and finally the tool breaks and the parts are scrapped. Therefore, chip evacuation and safety are key concerns in deep hole drilling. [0003] Such as Figure 1 to Figure 4 As shown, in the process of polishing the spiral flute, since the polishing brush is easy to polish the main land 6 on the outer periphery, a fillet K (circl...

AI Technical Summary

Problems solved by technology

However, due to the multiple times of grinding with the formed grinding wheel, it takes a very long time to achieve the precision grinding effect of the Ra0.1 mirror surface. One specification product requires two grinding wheels with different particle sizes, and the processing cost is too high. It is not conducive to the mass production of twist drills of different specifications; at the same time, the difference in the profile of two grinding wheels with different grain sizes should not be too large, otherwise the groove shape of the drill bit will change, resulting in a mismatch between the drill tip structure and the groove shape, and the twist drill cannot be used.

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