Although the calculation of gear height can be ensured with precision and analysis, special measurement tools must be used to verify the accuracy of gear height in actual production. The editor of Dalian Automation Processing Company will introduce commonly used gear height measurement methods below.

Tooth making height measurement method

The gear height measurement method is to measure the gear tooth position through a indexing plate or a simplified indexing instrument, and then calculate the gear height. The advantage of this method is that it is simple and easy to operate, suitable for the processing and measurement of small and medium-sized gears. However, in the processing and measurement of large gears, the tooth height measurement method has significant errors and is not very reliable.

Gear height gauge measurement method

Gear height gauge is a non-contact sensor that can measure the geometric parameters of gears through devices such as laser interferometer, grating ruler, angle encoder, etc. The advantages of this method are high accuracy, high degree of automation, and suitability for various gear types and sizes, but it requires certain technical and cost conditions.

Digital measurement method

The digital measurement method utilizes computer software and CNC measuring instruments to measure and analyze the height of gears. This method has the advantages of high automation, high precision, and good repeatability, which can effectively improve the accuracy and efficiency of gear processing. However, it requires a higher investment cost and requires higher requirements for the environment and equipment.

The calculation of gear height can be divided into two parts, namely finding the indexing circle and calculating the tooth shape factor. Below, we will provide a detailed introduction to the calculation process of gear height for automated machining.

Find the graduation circle

The calculation of gear height requires first finding the indexing circle of the gear. The indexing circle of a gear is a circular shape, which plays an important role in gear design because its size determines another important parameter of the gear - modulus, which is the foundation of gear design.

Calculation method for gear indexing circle:

M=Z/d

In the formula, M is the modulus, Z is the number of teeth, and d is the diameter of the gear indexing circle.

Calculate tooth shape factor

The tooth shape factor is a quantitative indicator of the tooth shape of a gear based on the indexing circle. The tooth shape factor is composed of a series of angles, mainly including tooth tip angle, tooth root angle, pressure angle, and top height coefficient.

Calculation method for tooth shape factor:

(1) Tooth apex angle

α= Arctan [(t/cos φ)- (tan φ/ p) +h/f]

In the equation, α Is the tooth tip angle, φ Is the pressure angle, t is the top height of the tooth, h is the top height, p is the pressure angle function of the indexing circle, and f is the radius of the indexing circle.

(2) Root angle

β= Arctan [(t/cos φ)+ (tan φ/ p) - h/f]

In the equation, β Is the tooth root angle, which is defined in accordance with the tooth tip angle.

(3) Pressure angle

φ= Arctan (v/u)

In the formula, v and u are the tooth shape angle and the busbar angle, respectively.

(4) Coefficient of top height

H/f=1.25M

In the formula, h is the height of the tooth tip, f is the radius of the indexing circle, and M is the modulus.