Two enveloping worm gear pair (hourglass worm gearing)

Enveloping worm gear pair (hourglass worm gearing) characteristics andoutstanding advantages:

Because the forming principle of difference, worm gear pair and the ordinarycylindrical worm gear pair compared, there are many different in meshingcharacteristics. Torus worm pair has the following characteristics in the meshingperformance:

1, at the same time the meshing teeth:

Hourglass worm gear worm gear pitch circle along the worm gear tooth surrounded.In theory, all of the tooth worm can engage, at the same time the meshing teeth,each tooth load carrying capacity is small, the worm will improve.

2, the tooth surface of a worm wheel bearing double line contact

In the second envelope process, because of the two principles of worm wheel tooth surface contact, there will be double contact phenomenon, double contactincreases the contact line length, reducing the load on the unit length of contact line.

3, the angle between the direction of relative movement and contact line directionof large

Usually the angle between the contact line direction and the direction of relative movement, called the lubrication angle, lubrication angle is bigger, better dynamicperformance is the formation pressure of oil film.

4, the induced normal curvature is small

Worm gear curvature of the same sign, while the ordinary cylindrical worm gearcurvature of opposite sign. Method the same sign of curvature induced normal curvature is bound to the induced normal curvature is less than normal curvature of opposite sign, so enveloping worm pair induced normal curvature is less than theinduced normal curvature side of ordinary cylindrical worm. The induced normal curvature smaller, more "fit" said two surface, the contact stress is small, the stronger ability of anti pitting. The above characteristics of the worm pair, broughtthe following prominent advantages to him

1, strong carrying capacity

Torus worm pair than the center distance of the cylindrical worm gear power transmission 2-3 times, if you pass the same power, worm gear box size only ordinary cylinder

Worm gear 1/3 to 1/2.

2, high transmission efficiency

Because the worm forming dynamic pressure oil film of good conditions, at work, in the liquid or supercritical liquid lubrication lubrication state, almost no direct frictionbetween the worm wheel and the worm metal, therefore, small friction, high transmission efficiency.

3, long service life

The main form of failure is worm gear wear, pitting and broken teeth, these forms offailure effectively overcome in the worm gear pair, under the same conditions, the service life of worm gear pair is 5-10 times that of ordinary cylinder worm drive.