The modification method of tractor gear tooth direction

Tooth profile modification is usually the shape of the drawing, that is, “drum tooth”. Tooth profile modification can be divided into hot pre modification and hot post modification, hot pre modification is mainly shaving modification, hot post modification is mainly grinding modification, and electrochemical modification is also available.

1. Shaving

When the axial shaving technology is used for tooth profile modification, the function of the shaving machine is needed. The traditional mechanical shaving machine, such as y4232w, makes the worktable swing by mechanical device, so as to shave the tooth surface with high middle and low ends, which becomes “drum shaped tooth”. The CNC shaving machine uses the CNC system to control the movement of the worktable to shave the tooth surface which is high in the middle and low in both ends. The practice shows that it is more accurate and stable to use the CNC shaving machine for tooth profile modification. It is difficult to adjust and the quality of shaving machine is not stable.

When the radial shaving technology is used for the tooth profile modification, the shaving cutter needs to be grinded to achieve the tooth profile modification, that is, the tooth surface of the shaving cutter should be repaired to be low in the middle and high at both ends, so that the “drum shaped tooth” gear can be shaved.

During shaving, the tooth profile modification can be carried out simultaneously with the tooth profile modification.

2. Gear grinding

By using the CNC worm wheel gear grinding machine and the forming gear grinding machine with the function of tooth profile modification, the tooth profile modification after hot grinding can be realized. When the worm wheel is used to grind the gear of the gear grinding machine, the CNC system controls the radial feed movement of the worm wheel. If the feed at both ends is large and the feed in the middle is small, the “drum shaped gear” can be grinded. When the gear is grinded by the form grinder, the operator of the grinder can also carry out the tooth profile modification and the tooth direction modification at the same time.

3. Electrochemical modification

The electrochemical method is the same as the method of tooth profile modification, and it can be carried out at the same time.

In the application of gear shaping technology, it is necessary to determine the shaping method according to the product performance. Small power and low performance tractors can not be reshaped, general medium power tractors can only be reshaped simply, high-performance medium power products and general High-power Tractor products can be reshaped, The High-power Tractor Products with high-performance mechanical shift can also be used for gear grinding. For the power shift transmission gear, the technology of gear grinding for gear profile modification and gear direction modification should be used at the same time.

For a pair of gear pairs, both gears can be reshaped, or only one gear can be reshaped, matching gears are not reshaped.

As shown in the figure, it is the effect picture of our shaping test. The gear pair is modified by grinding, and the matched pair of gears are all modified by tooth profile, but only one gear is modified by tooth direction, which is installed in the transmission system for loading test. Before the test, the tooth surface shall be colored, and the running in condition of the tooth surface after the load test is shown in Fig. 7.

Figure shows the transmission case of a tractor. For the gears in the gearbox, we use the shaving method to modify the tooth profile. The field test shows that the noise is reduced by 2 dB (a).