Design And Research Of Dual-cone Double Enveloping Hourglass Worm Gear Pair And Its Key Manufacturing Equipment

Double enveloping hourglass worm gear pair enjoys bigger carrying capacity, higher transmission efficiency and longer service life than the common worm gear pair. Besides, being applicable for all of the common worm gear pair applied conditions, double enveloping hourglass worm gear pair is the upgrading and alternative products of the common worm gear pair. However, at present, the double enveloping hourglass worm gear pair still has not replaced the common worm gear pair and been applied in the real life extensively. The fundamental reason for such a phenomenon is that its manufacturing cost is quite high. To solve the above mentioned problem and promote the development of double enveloping hourglass worm gear pair, this paper takes the dual-cone double enveloping hourglass worm gear pair as the object to conduct related researches and attain achievements with practical values which mainly represented in the following aspects:1. It develops the multi-objective optimizing designing model for the dual-cone double enveloping hourglass worm gear pair. Such a model takes three variable parameters affecting the mathematic model of hourglass worm gear pair directly as the optimization variables. On the basis of considering the performance of dual line of contact, it sets the minimum oil film thickness and the distributing scope of line of contact as the optimizing objectives; it treats the avoidance of the hourglass worm undercut and side tooth crest sharpening as the constraint condition. It verifies the effectiveness of this optimization model through the optimization designing of an actual example, calculation comparison and analysis and the performance test on products before and after optimization. Such achievement could be used in the designing of the dual-cone double enveloping hourglass worm gear pair and provides a theoretical foundation for the series designing before the batch manufacturing of products.2. It designs the key manufacturing equipment for the batch manufacturing of dual-cone double enveloping hourglass worm gear pair. One is the CNC grinding machine for the dual-cone double enveloping hourglass worm gear pair being applicable to worm tooth surface accurate grinding; the other is the hourglass worm gear numerical control machine tool applicable to the hourglass worm gear hob relief grinding. It uses the above mentioned equipment to manufacture the dual-cone double enveloping hourglass worm gear pair and verify the practicability of the equipment. At the same time, it applies and achieves related authorization of the patent for intervention. Such achievement provides guarantee of manufacturing equipment for the batch manufacturing of dual-cone double enveloping hourglass worm gear pair.3. It analyzes the difficulty of hob relief grinding of dual-cone double enveloping hourglass worm gear pair and deduces the formula for calculating the hob relief angle of the dual-cone double enveloping hourglass worm gear pair calculating by making comparison with the worm gear hob of common cylindrical worm gear pair. It designs the hob for the dual-cone double enveloping hourglass worm gear pair and establishes the three-dimensional model for the hob. It builds the axle section model for the basic worm of hourglass worm gear hob, on the basis of which it also proposes the method for the error detection and compensation in the hob basic worm manufacturing and makes verification through test. Based on the hourglass worm gear hob CNC relief grinding equipment, it proposes the relief angel relief-grinding method for the dual-cone double enveloping hourglass worm gear hob improves the manufacturing efficiency and accuracy and verifies the effectiveness of the manufacturing method through test. Such achievement solves the problem of hob production which is the bottleneck limiting the batch production of the dual-cone double enveloping hourglass worm gear pair.