China 
Africa 
Explore chapters and articles related to this topic
Introduction to Electric Motors
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
However, there are some disadvantages of using gearing systems. The main problem is backlash introduced by gearing systems. Backlash is the gap between the teeth of two adjacent gears. Thus, the rotational backlash of a gearing system is the accumulated backlash from all paired gears. It can be measured as the free rotational angle at the gearing system output shaft when the input shaft is locked or vice versa. In precise motion control applications involving frequent load reversals (e.g., CNC machines, elevators, wind pitch control systems), backlash plays a crucial role in determining the repetitive positioning accuracy. For this type of application, gearing systems must be made with low backlash and high stiffness. For demonstration purposes, the theoretical backlash of the gearing system and torsional stiffness is shown in Figure 1.37.
Gear Tooth Design
Published in Stephen P. Radzevich, Dudley's Handbook of Practical Gear Design and Manufacture, 2021
In a set of meshing gears, the backlash that exists is the result of the actual center- distance at which the gears operate, and the thickness of the teeth. Changes in temperature, which may cause differential expansion of the gears and mountings, can produce appreciable changes in backlash.
Gear Cutting/Manufacturing
Published in Zainul Huda, Machining Processes and Machines, 2020
Gears. Gears are crucial parts of many machines. A gear is a machine element that has teeth cut around cylindrical or cone-shaped surfaces with equal spacing. By meshing a pair of gears, rotational speed and power can be transmitted from the driving shaft to the driven shaft. Hence, gears help increase torque output. Gears’ teeth are generally surface hardened to ensure a high wear resistance combined with toughness (Huda, 2020). An important design parameter of a gear is its module. A gear’s module is defined as the pitch diameter divided by the number of teeth. A variety of gear types are used as machine elements in motors and machineries. Some basic types of gears include spur gear, helical gear, bevel gears, worm gears, and the like (Lelikov, 2009). The teeth on spur gears are straight whereas the teeth on helical gears are angled with a helix angle. Since the scope of this book does not permit the explanation of all the types of gears, only spur gears are briefly described in the following paragraph.
Selecting an optimal contractor for production outsourcing: a case study of gear grinding
Published in Journal of the Chinese Institute of Engineers, 2020
Kuen-Suan Chen, Tsang-Chuan Chang, Yi-Yu Guo
Gears transmit power, change the direction of motion, and alter rotational speed, and are thus widely used in mechanical transmission devices. In order to demonstrate the applicability of the proposed contractor selection matrix, we consider a case study of the outsourcing of a gear product. The manufacture of gears involves several processing procedures: grinding is one such crucial process. The grinding process includes the four important quality characteristics shown in Table 2. With regard to manufacturing time, contracting firms have certain restrictions: at least 55 sec but no more than 65 sec (i.e. and ). The structure of a gear product is shown in Figure 3.
Multi-objective spur gear design using teaching learning-based optimization and decision-making techniques
Published in Cogent Engineering, 2019
Edmund S. Maputi, Rajesh Arora
There are numerous types of gears viz. spur, helical, worm, straight and spiral bevel gears which have been investigated in the literature. Zolfaghari, Goharimanesh, and Akbari (2017) focused on minimizing the volume of a straight bevel gear by using an approximating formula for the frustum of a cone to determine volume. In this study, an analytical method known as AGMA 2001-D-04 (American Gear Manufacturers Association) and an evolutionary algorithm, Simulated Annealing (SA) were applied with improved results obtained using the latter. The worm-wheel gear system was investigated by Mogal and Wakchaure, (2013) while applying a multi-objective formulation to investigate three parameters using a genetic algorithm. Spur and helical gears have been investigated extensively as single and multi-objective problem formulations in literature.
Modeling and experimental verification of cutting forces in gear tooth cutting
Published in Machining Science and Technology, 2018
Gears are widely used in industry to transmit power or rotary motion while maintaining an intended torque and angular velocity ratio together with smooth motion and high efficiency. To achieve these favorable conditions, most of the gears have their tooth form based on involute curve. As the gear tooth flanks have a complex and precise shape, special attention is paid to gear during its manufacturing. Although a variety of gear forming methods such as casting, stamping, rolling, forging, extrusion, powder metallurgy, and machining are commercially available, gears should be produced by machining to achieve the desired dimensions, shape and surface finish. In practice, gear machining process can be performed by milling, broaching, hobbing, shaping and rack cutting. Of these methods, gear milling can be used for production of all types of external gears, performed on a conventional milling machine, and is economical and suitable for the production of replacement gears, small lot production, roughing and finishing operations.