General description of gear tooth punching accuracy (for reference)

gearOrdinary punching accuracy: the quality of the cutting surface of the punching parts, the bending deformation of the punching parts, the tooth profile accuracy of the punching parts and the dimensional accuracy of the ordinary punching teeth are explained as follows, for reference.

XNUMX. The quality of the shear surface of the punching parts

There are four obvious parts on the shear surface of the punching part, namely, rounded band (also called sag), bright band (also called shear band), shear band and burr, as shown in the figure.

The quality of the shearing surface is related to the accuracy of the punching die, the gap between the convex and concave dies and the material of the punching part.The parameters of the punching teeth also directly affect the quality of the shear surface.

a. According to the different materials of the punching parts, the reasonable gap between the punch and the die is shown in the table below.

The data in the table is the ratio of the single-sided gap to the material thickness.

b. In the case of reasonable clearance, the quality of the shear surface of the punching parts is shown in the table below.

c. The surface roughness of the punching cut surface is shown in the table below.

Second, the bending deformation of the punching parts

During the punching process, the punching parts are bent and deformed due to the influence of the punching pressure of the tooth top part.The degree of deformation is related to the material properties, the gap between the convex and concave molds and the force.

The figure below is the relationship curve between the bending deformation of the punch and the gap between the punch and the die.The larger the ratio of the gap, the easier it is to produce bending deformation.

XNUMX. Tooth profile accuracy of punching parts

Due to the limitation of the current technology level, the tooth profile accuracy of small-module gears has a certain gap compared with hobbing and milling, and the tooth profile parameters still meet certain conditions, otherwise the punching cannot be achieved.

a. No matter it is involute tooth profile or non-involute tooth profile, the tooth profile curve is not allowed to have sharp points or inflection points, and the straight line and the arc must be smoothly connected.

b. The parameter values ​​of various tooth profiles must meet the values ​​specified in the following table.But p, r, and P1 cannot be less than 0.006mm.

Fourth, the dimensional accuracy of ordinary punching teeth

According to the material of different thickness and the size of the parts, the achievable dimensional accuracy is shown in the table below.