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.

Inverted tooth chain sprocket with frequency modulated meshing

Abstract: An inverted tooth chain drive system includes an inverted tooth chain (20) structured for inside flank engagement. The chain includes link rows (W) each including leading inside flanks (Fi) that project outwardly relative to trailing outside flanks (Fo) of a preceding link row. The system further includes a sprocket (10) with which said inverted tooth chain is drivingly engaged. The sprocket includes a plurality of teeth circumferentially spaced about an axis of rotation, each tooth comprising an engaging flank (E) and a disengaging flank (D). Some of the teeth (T1) are defined with a first tooth form in which said engaging flank thereof is defined with a first pressure angle (PA1) and others of said teeth (T2) are defined with a second tooth form in which the engaging flank (E' ) thereof is defined with a second pressure angle (PA2) that is different from the first pressure angle in order to stagger or modulate the initial meshing impacts between the leading inside flanks of the chain and engaging flanks of the sprocket teeth. The sprocket can be optimized for manufacture by a hobbing process, by arranging the different tooth forms in a specific 'hob-compatible' pattern.

Research on the Design and Modification of Asymmetric Spur Gear

Abstract: A design method for the geometric shape and modification of asymmetric spur gear was proposed, in which the geometric shape and modification of the gear can be obtained directly according to the rack-cutter profile. In the geometric design process of the gear, a rack-cutter with different pressure angles and fillet radius in the driving side and coast side was selected, and the generated asymmetric spur gear profiles also had different pressure angles and fillets accordingly. In the modification design of the gear, the pressure angle modification of rack-cutter was conducted firstly and then the corresponding modified involute gear profile was obtained. The geometric model of spur gears was developed using computer-aided design, and the meshing process was analyzed using finite element simulation method. Furthermore, the transmission error and load sharing ratio of unmodified and modified asymmetric spur gears were investigated. Research results showed that the proposed gear design method was feasible and desired spur gear can be obtained through one time rapid machining by the method. Asymmetric spur gear with better transmission characteristic can be obtained via involute modification.

Simulation Research on the Time-Varying Meshing Stiffness and Vibration Response of Micro-Cracks in Gears under Variable Tooth Shape Parameters

Abstract: The gear is one of the important parts of a rotary gearbox. Once catastrophic gear failure occurs, it will cause a great threat to production and life safety. The crack is an important failure factor causing changes in time-varying stiffness and vibration response. It is difficult to effectively identify the vibration response and meshing stiffness changes when there is a fine crack in the gear. Therefore, it is of great importance to improve the accuracy of meshing stiffness calculation and dynamic simulations under micro-cracks. Investigations of meshing stiffness and the vibration response of a gearbox is almost all about fixed gear shape parameters. However, the actual production process of gear system needs to change gear shape parameters. In this paper, the meshing stiffness and vibration response of the dynamic simulation signals of gear teeth with different crack depths at different tooth shape parameters (the pressure angle, the modulus, and the tooth number) were calculated, respectively. The influence of cracks on the vibration response was investigated by the fault detection indicators, the Root Mean Square (RMS), the kurtosis, and the crest factor. The result shows that when the pressure angle and modulus change, the vibration response changes erratically. However, when the tooth numbers change, the vibration response changes regularly. The results could be a guide for choosing gears in different shape parameters when system stability is the aim.