Adjust the correction amount of vertical wheel position when machining spiral bevel gear small wheel Δ Em, the table lists the different values of the vertical wheel position of the spiral bevel gear pinion, and studies its influence on the contact condition.

Serial number	a	b	c	d	e
Vertical wheel position /mm	37.1528	37.6528	38.1528	38.6528	38.8528

TCA analysis is made according to the vertical position values of spiral bevel gear pinion in the above table. See the following figure for contact conditions.

By observing the change of contact area and motion curve, when the vertical wheel position of spiral bevel gear small wheel is adjusted in the positive direction, the inner diagonal contact is generated, and the fishtail contact phenomenon is intensified. When the vertical wheel position of spiral bevel gear small wheel is adjusted in the negative direction, the inner diagonal contact phenomenon is reduced, the outer diagonal is generated, and the fishtail contact is improved; By observing the change of the slope k of the motion curve when the abscissa is 0, the vertical wheel position of the spiral bevel gear pinion is adjusted to the positive direction, the slope k of the motion curve when the abscissa is 0 is less than 0, and the contact area moves to the tooth root; The vertical wheel position of spiral bevel gear small wheel machining is adjusted in the negative direction, the slope k of the motion curve when the abscissa is 0 >0, and the contact area moves towards the tooth top.