We provide non-standard customization of gears. When selecting gears, we need to pay attention to the following factors:
It is necessary to determine whether the gear is straight tooth or helical tooth. The straight tooth has strong bearing capacity and bears large torque, but it will produce large noise during high-speed operation. The helical tooth has large coincidence degree, stable transmission and low noise. It is suitable for high-speed operation, but there will be axial force. Then determine the module and the number of teeth. In the case of the same number of teeth, the larger the module, the larger the gear. In the case of the same module, the more the number of teeth, the larger the gear. When determining the gear size, the appropriate gear size should be selected according to the load. In the operation of rack and pinion transmission, the smaller the gear, the smaller the load torque will be, but the number of teeth cannot be reduced indefinitely, It needs to be determined according to the actual use. Secondly, it needs to determine the accuracy of the gear. The unified accuracy of the gear of our company is level 6. Finally, it needs to determine the aperture size and tolerance of the gear. If it fits with the shaft installation, it needs to provide the shaft size and shaft tolerance. It also needs to consider the installation method, whether it is jacketed installation or hot installation, because of different installation methods, The tolerances between hole shafts are also different. The above are some parameters that need to be paid attention to when customizing gears according to shaft output mode. Other different parameters need to be determined for flange output and hollow shaft output, which can also be produced according to design drawings.
Basic calculation formula of helical gear
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Name
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Symbol
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Calculation formula
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Normal pressure angle
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an
|
an=20°
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Normal addendum height factor
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han*
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han*=ha*=1或0.8
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Normal Head Clearance Coefficient
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cn*
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cn*=c*=0.25或0.3
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Helix angle
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β
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β1=-β2（一般β取8°~20°）
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End face modulus
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mt
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mt=mn/cosβ
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End pressure angle
|
at
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tgat=tgan/cosβ
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End face addendum height coefficient
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hat*
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hat*=han*cosβ
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End face clearance coefficient
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ct*
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ct*=cn*cosβ
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Equivalent number of teeth
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zv
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zvi=zi/cos3β
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End face displacement coefficient
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xt
|
xti=xnicosβ
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Dividing circle diameter
|
d
|
di=mtzi
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