Abstract
This paper analyzes the wear of the support spring of sprag clutches for different structural parameters during overrunning state. Specifically, the stiffness model of the support spring is established based on the characteristics of the variable helix angle, and also the supporting force model is established according to the energy conservation law during the working process of the sprag clutch. Meanwhile, the relative rotation speed between the support spring and the wedge is analyzed by dynamic simulation method. Furthermore, the wear model of the support spring in process of overrunning is established based on Archard wear theory. The results show that there is a linear relationship between supporting force and spring radial displacement compression. In addition, increasing free length and wire diameter of springs will aggravate the wear of springs, whereas enlarging pitch diameter of springs will reduce it. When free length is increased from 270 to 290 mm, the wear time is reduced by 20.88%; when wire diameter is increased from 0.5 to 0.7 mm, the wear time is reduced by 42.75%; when pitch diameter is increased from 2 to 2.4 mm, the wear time is increased by 3.35%. The degree of influence of the structural parameters on the spring wear from large to small is free length, wire diameter, and pitch diameter. Exactly speaking, when wear time is 100 hr, the relative sensitivity of structural parameters affecting the wear of the support spring is in order of free length (2.2), wire diameter (0.97), and pitch diameter (0.08). The research provides a reference for the design and optimization of the support spring for highly reliable sprag clutches.
Highlights
Establishment of Helix Equation ofSupport Spring. e free length of the support spring of the sprag clutch is L (the expanded length of the spring in a free state), the pitch is p, the pitch diameter is D, the radius of the spring coil is RL, the number of effective coils of the spring is n, and the wire diameter is d
Academic Editor: Hui Wang is paper analyzes the wear of the support spring of sprag clutches for different structural parameters during overrunning state
When free length is increased from 270 to 290 mm, the wear time is reduced by 20.88%; when wire diameter is increased from 0.5 to 0.7 mm, the wear time is reduced by 42.75%; when pitch diameter is increased from 2 to 2.4 mm, the wear time is increased by 3.35%. e degree of influence of the structural parameters on the spring wear from large to small is free length, wire diameter, and pitch diameter
Summary
Support Spring. e free length of the support spring of the sprag clutch is L (the expanded length of the spring in a free state), the pitch is p, the pitch diameter is D, the radius of the spring coil is RL, the number of effective coils of the spring is n, and the wire diameter is d. E free length of the support spring of the sprag clutch is L (the expanded length of the spring in a free state), the pitch is p, the pitch diameter is D, the radius of the spring coil is RL, the number of effective coils of the spring is n, and the wire diameter is d. According to the method for establishing the helix equation of circumferential spring [16], the process of establishing the helix equation of a support spring is as follows: Set point Q to rotate uniformly with frequency w1 along the circle with radius R (R D/2) and rotate uniformly with frequency w2 along the circle with radius RL. Setting up θ1 w1t and θ2 w2t, when the number of support springs is n, let θ1/θ2 n; in addition, substituting into equation (1), the helix equation of the support spring of the sprag clutch is obtained as follows:.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
