Pressure angle

About: Pressure angle is a research topic. Over the lifetime, 1373 publications have been published within this topic receiving 10245 citations. The topic is also known as: angle of obliquity.

A Novel Method for Calculation Gear Tooth Stiffness for Dynamic Analysis of Spur Gears With Asymmetric Teeth

Abstract: Recently, there have been a number of research activities on spur gears with asymmetric teeth. The benefits of asymmetric gears are: higher load capacity, reduced bending and contact stress, lower weight, lower dynamic loads, reduced wear depths on tooth flank, higher reliability, and higher efficiency. Each of the benefits can be obtained through asymmetric teeth designed correctly. Gears operate in several conditions, such as inappropriate lubrication, excessive loads and installation problems. In working conditions, damage can occur in tooth surfaces due to excessive loads and unsuitable operating conditions. One of the important parameters of the tooth is stiffness, which is found to be reduced proportionally to the severity of the defect by asymmetric tooth design as described in this paper. The estimation of gear stiffness is an important parameter for determining loads between the gear teeth when two sets of teeth are in contact. In this paper, a 2-D tooth model is developed for finite elements analysis. A novel formula is derived from finite element results in order to estimate tooth stiffness depending on the tooth number and pressure angle on the drive side. Tooth stiffness for spur gears with asymmetric teeth is calculated and the results were compared with well known equations in literature.Copyright © 2014 by ASME

Tooth profile for compressor screw rotors

Abstract: An improved tooth profile for compressor screw rotors is disclosed. In the tooth profile, the following-side first curve of the male rotor is generated using a generation parameter of a quadratic function f(x)=a 10 x 2 +b 10 x+c 10 whose constants are optimized to meet specified constraint conditions. The above constraint conditions include an increased pressure angle for achieving good cutting condition of the rotors, a sealing surface suitable for minimizing the negative torque applied to a following rotor due to the gas pressure in the trapped pocket volume defined between the rotors, a large surface contact between the two rotors for improving the sealing effect as well as the durability of the rotors, and a minimized specific sliding at the driving force transmission part of the rotors for reducing the operational vibration and noise of the rotors.

Toothing and gears made therewith

Abstract: A tooth according to the invention is such that its flank (foot flank) (1B) situated inside the not entirely circular pitch curve (PA) follows an involute of a circle determined by a pressure angle (p), and has a face (2B) outside the pitch curve such that its current point (M) is determined by the intersection of the flank (1A) of the co-operating tooth with the tangent to the circles defining the flank (1A) passing through the instantaneous point of contact (N) of the pitch curves (P'A, P'B). The pitch curves may be circular arcs, logarithmic spiral arcs, elliptical arcs, or a succession of such arcs around an open or a closed curve in order to form gearing. Some lengths of the pitch curves may have no teeth.

Computer Aided Design of Asymmetric Gear

Abstract: Gear design becomes inevitable for the development of any mechanical system and it necessitates considerable expertise. Due to the evolution of new materials and manufacturing processes, the utilization of asymmetric gears increases in recent years. Designers will be able to develop gear drives to handle larger torque with lesser noise and vibrations with the asymmetric profile. However the existing design procedure of symmetric gears does not holds good for these asymmetric gears. Hence by modifying tooth form factor, stress concentration factor, and load sharing factor, a MATLAB  code has been developed for designing asymmetric spur gears. Pressure angle limits were initially arrived by considering the gear tooth peaking and law of gearing. With in the range of pressure angle values, the asymmetric gear teeth which experiences minimum bending and contact stresses for the given loading condition can be chosen. In addition with the known number of tooth, module, and pressure angles of driving and coast side, asymmetric gear tooth coordinates were obtained which can be directly used for actual gear manufacturing