by National Aeronautics and Space Administration, US Army Aviation Systems Command, For sale by the National Technical information Service in [Washington, DC, St. Louis, Mo.], [Springfield, Va .
Written in English
|Other titles||Application of face gear drives ....|
|Statement||F.L. Litvin ... [et al.].|
|Series||NASA technical memorandum -- 105655., AVSCOM technical report -- 91-C-036., AVSCOM technical report -- 91-C-36.|
|Contributions||Litvin, F. L., United States. Army Aviation Systems Command., United States. National Aeronautics and Space Administration.|
|The Physical Object|
The use of face-gears in helicopter transmissions was explored. A light-weight, split torque transmission design utilizing face-gears was described. Face-gear design is discussed. Topics included basic design geometry, tooth generation, limiting inner and outer radii, and recommendation for the gear by: The use of face gears in helicopter transmissions was explored. A light-weight, split torque transmission design utilizing face gears was described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, and structural stiffness. The bearing contact in a face gear drive is localized (see section ) to avoid the separation of tooth surfaces and edge contact due to misalignment. The advantages of a face gear drive are: (1) The possibility to split the torque in a gear transmission, particularly in a . The design of the face gear drive presented by Litvin in,,,, is based on application of a conventional spur involute pinion being in contact with the conjugated face gear, representing the most applied solution in the literature for the by:
An important example of application of a face-gear drive with intersected axes is in the helicopter transmission (Fig. ). The manufacturing of face-gears by a shaper was invented by the Fellow Corporation. The basic idea of generation is based on simulation of meshing of the generating shaper with the face-gear being generated as the meshing of the pinion of the drive with the face-gear. Face gear drives have found application in helicopter transmissions. Figure 1 shows an example of a design wherein the driving pinion is simultaneously in mesh with two face-gears. Such a design permits splitting of the torque between two face-gears. This leads to a transmission design . power transmission elements that determine the speed, torque, and di-rection of rotation of driven machine elements. Gear types may be grouped into five main categories: Spur, Helical, Bevel, Hypoid, and Worm. Typically, shaft orientation, ef-ficiency, and speed determine which of these types should be used for a partic-ular application. Table File Size: KB. The face gear pair has been applied in the main reducer of helicopter. Considering the nonlinear backlash, time-varying meshing stiffness and static transmission error, a six degree-of-freedom lumped parameter dynamic model coupling with flexional, torsional and axial motion of the face gear pair for helicopter is developed.
Face gear drives are focused by many researchers, due to several strong-points versus traditional spiral bevel gear drives. However, calculation solutions of face gear dynamics associated with engagement impact energy decay are not to be constructed, according to the limited published issues. Thus, in the study, a calculation solution of engagement impact energy decay of face gear drives is Author: Zhengminqing Li, Hao Wu, Rupeng Zhu. Peng M Parametric instability investigation and stability based design for transmission systems containing face-gear drives. PhD diss, University of Tennessee, 7. Peng M, Desmidt H, Saribay ZB, Smith E. Parametric instability of face-gear drives with a spur pinion. American Helicopter Society 67th Annual Forum, Virginia Beach, VA, 8. The gear reduction of a turbine powered helicopter is in the order of The transmission must be able to cope with the high torque values produced when driving a rotorsystem. The second key function is the transmission of the main rotor thrust to the hull. An important aspect of the transmission . The paper covers application of face-gear drives in helicopter The pinion which serves the two face-gears is a conventional transmissions. The advantage of this design is the possibility to spur gear with an even number of teeth. If the spur gears were split the torque between two face-gear drives.