Maintenance of drum gear coupling

Published: 2017-12-15

The drum gear coupling consists of an inner gear ring with the same number of teeth and a flange half coupling with external gears.The external teeth are divided into straight teeth and drum teeth. The so-called drum teeth means that the external teeth are made into a spherical surface. The spherical surface is on the gear axis. The tooth side clearance is larger than that of ordinary gears. Drum-shaped gear couplings can be used. Allows larger angular displacement (compared to the straight tooth coupling), the contact condition of the tooth can be improved, the ability of transmitting torque is improved, and the service life is prolonged.The contact state along the tooth width when there is an angular displacement.

Good lubrication is the operation of the drum gear coupling and it also slows down wear.

Under the conditions of sufficient tooth root bending strength and tooth surface contact strength, the tooth width should be determined with a larger degree of coincidence, and the tooth width should not be blindly increased, so as not to increase the size of the structure.The general tooth width factor is 8-14.The small tooth width should be determined by the allowable tooth root stress, and the width required for the displacement of the force point along the tooth width caused by the inclination angle between the shafts should also be considered.

An important way to increase the service life of drum gear couplings.The tooth width coefficient affects the tooth root bending strength and tooth surface contact strength of the tooth. The larger the tooth width coefficient, the greater the strength of these two items. The tooth width coefficient affects the coincidence degree. When the tooth width coefficient is less than the value range, its value Increase has a greater impact on the increase in coincidence, and when it is greater than this value, the increase in device value has a smaller impact on the increase in coincidence. For drum-shaped gear couplings with arc drum curve, the tooth width still determines the drum. The radius of the degree circle is also a parameter of the backlash. The larger the tooth width, the larger the radius of the bulge circle, and the larger the backlash required. Therefore, the following bright spot requirements are required:   

The smaller the gear tooth concentrated load is, the better, and the curvature of the tooth surface is proportional to the circumference of the drum, so the drum radius is as large as possible.The curvature radius of the bulge curve is proportional to the single-sided thinning of the internal tooth, so the bulge circle radius should be as large as possible.The radius of curvature of the bulge curve is proportional to the single-sided thinning of the internal tooth, that is, it is related to the meshing gap of the tooth. Insufficient thinning may cause interference, and excessive thinning will weaken the strength of the tooth, and the backlash will be large. .

The drum-shaped tooth surface of the drum-shaped gear coupling enables the contact conditions of the inner and outer teeth to avoid the disadvantages of the spur tooth end edge extrusion and stress concentration under the condition of angular displacement. At the same time, the friction and wear conditions of the tooth surface are improved. , The noise is reduced, and the maintenance period is long.The tooth end of the outer gear sleeve is in the shape of a horn, which makes the assembly and disassembly of the inner and outer gears convenient.

High-speed drum gear couplings are usually lubricated with lubricating oil. The tooth surface requires continuous lubrication. The lubricating oil should be drained smoothly, otherwise the temperature of the tooth surface will rise and accumulate moisture and dirt. The lubricating oil needs to be filtered by an oil filter. The clearness is less than 10 microns. Some important high-speed drum gear couplings can also adopt the structure of oil collecting grooves. That is, the oil collecting groove is machined in the shaft hole of the external gear, and the groove connected to the oil collecting groove is drilled at the bottom of the tooth groove of the external gear. The oil hole uses the centrifugal force generated by the high-speed operation of the drum-shaped gear coupling to spray oil into the meshing part of the inner and outer teeth to make it fully lubricated.