Area of Existence of Involute Gears (original) (raw)
Related papers
2019
Today, involute spur gears are the most common in mechanical engineering. However, besides of the benefits, involute teeth present several disadvantages. To overcome those disadvantages, designers resort to changes that increase the complexity of equipment, cutting tools that lead to the expensive cost. On another hand, gear and transmission, namely sinusoidal gear and transmission is known by higher properties. The results of the simulation of involute and sinusoidal gearing are described in the article. Proved that, sinu-soidal gears have higher performance parameters. Simulation confirmed that sinusoidal gear have higher bending strength, lower contact stress, reduced contact friction and tension in the edging contact, improved performance indicators of transmission. The advantages are due to the following features of the sinusoidal gears geometry: gear tooth profile outlined by a smooth sine wave curve; greater teeth thickness on the pitch circle; wide range of coast flank pressure angle. A new method of gears machining is described. This technology makes it possible to reduce number of expensive and complex gears cutting tools and gears machine tools, greatly simplifies technology of tooth cutting and reduces the cost of gears manufacturing by a numerous times. The method has a wide versatility, provides the opportunity to produce a variety of gears types including, gears with asymmetric teeth.
[21]) on external modified involute gear teeth is presented in this technical report. The teeth in question are composed of an involute working profile from the outer to the form circle of the gear and of a circular fillet from the form to the root circle, replacing the conventional trochoidal fillet. This circular fillet has been proved to increase the bending strength of the gear without altering any other of its functional characteristics (Spitas et al. [22]) and therefore it can readily replace the corresponding conventional gears in a mechanism.
American Journal of Engineering and Applied Sciences
The paper presents an original method for the determination of the yield of the gearbox, gears forces, gearbox and power. It analyzes the influence of certain parameters which affects the efficiency of the gearbox. Also an original method for the determination of the yield of the drive shafts oriented on the basis of the ratio of contact is presented the brief. The relations submitted, can be dynamic synthesis of the drive shafts oriented, in order to enhance the effectiveness of the mechanisms of mesh.
Analysis and optimization of contact ratio of asymmetric gears
2016
The contact ratio of spur gears is a critical parameter that affects gear drive performance. The influence of this parameter on the gear drive load capacity, efficiency, and noise and vibration is well known. There are studies (Refs. 1–3) dedicated to the analytical and experimental comparison of gears with low and high contact ratios. The dynamics and efficiency of high-contactratio asymmetric tooth gears were described in (Refs. 4–5). These publications explore contact ratio using a very similar evaluation approach. The gears are designed traditionally, based on a preselected basic (or generating) rack. This makes the contact ratio dependent on the number of teeth of mating gears, basic rack addendum, and X-shifts. A contact ratio is considered nominal, as it is designed without influence of deflections under the operating load. Comparable gear sets with different contact ratios are identical in numbers of teeth, tooth size, and modules. Such comparisons might have some theoretica...
A quick and efficient algorithm for the calculation of gear profiles based on flank involutization
This paper introduces the concept of flank involutization for the determination of conjugate gear tooth profiles. Instead of following a point-to-point analytical approach to the problem of determining the path of contact and the geometry of the generating rack and the mating wheel, the actual tooth flank is considered to be composed of infinitesimal local involutes and therefore a closed solution can be achieved. Due to its simplicity, the method is very fast compared to the standard theory of gearing and this is particularly useful in problems requiring iterative calculations of the tooth geometry such as gear optimization.
Theory and Applications Based on S-Gear Geometry
Recent Advances in Gearing, 2021
The chapter starts with the theory defining S-gears and their properties and compares S- and involute gears. Most of the text deals with cylindric spur gears. S-gears are defined with the half-symmetric rack profile, which then uniquely defines the path of contact and gears. Reshaping of the gear flanks for external and internal gear pairs is presented here and thermal behavior discussed and compared with the involute gears. Experimental verification of S-gears theory, especially durability and thermal behavior of importance for plastic gears is presented. So, in this chapter a material combination of interest was alloy steel and POM (which was only heat stabilized). The chapter presents some specific information about this. And finally, the planocentric gearbox focused on high-tech industry (e.g., robotics) is presented. The problem is how to achieve required properties. So, all possible analytical tools should be used to minimize backlash and many other parameters which is also pr...
Direct Gear Design® for Automotive Applications
SAE Technical Paper Series, 2005
This paper presents Direct Gear Design-an alternative method of analysis and design of involute gears which separates gear geometry definition from tool selection to achieve the best possible performance for a particular product and application. This method has successfully been applied for a number of automotive applications. Some examples will be presented at the end of the paper.
Utilization of Computer Programs in Modelling of Gears with Asymmetric Involute Teeth
2008
This paper studies the equations of rack cutters for generating helical gears with asymmetric involute teeth. By applying profile equations of the rack cutter, the principle of coordinate transformation, the theory of differential geometry, and the theory of gearing, the mathematical models of involute helical gear is given. The paper presents aspects regarding the utilisation of computer programmes for computer aided design graphical modelling of cylindrical gears with asymmetric involute teeth. Software applications in the domain of computing the points that define the profile and the line of tooth flanks, as well as their 2 and 3 D representation are performed.