Abstract

When fluctuations in the drive pulley speed are transmitted to the driven pulley via the metal V-belt, the transmitted fluctuations are attenuated according to the belt slippage. The research discussed in this paper focused on these fluctuations in the pulley speeds and developed a method for estimating the instantaneous safety factor for belt clamping force. First, a vibration model was built by regarding the drive and driven pulleys as a one-dimensional vibrating system connected by elastic bodies. Based on this vibration model, the instantaneous safety factor was then estimated from changes in the pulley speeds. In order to verify the method’s validity, the actual safety factor was calculated by measuring the driveshaft torque and belt clamping force in a test vehicle and compared with the value estimated using the proposed method. In verification testing, changes in vehicle body weight and left-right wheel differential were applied to the test vehicle. With the assumption that aging may affect the results, verifications were also performed with two test pulleys with different coefficients of friction.The results verify that, in the required estimation accuracy range of a safety factor of 1.25 or lower, instantaneous safety factor can be estimated to within an error range of 2%. Using the proposed method, belt clamping force can be adapted even for changes in friction coefficient, a traditionally unknown variable.

References

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Author (organization or company)

• Kyohei SAKAGAMI（Automobile Center）

Publication Information

Article of Honda R&D Technical Review Vol.31 No.2 (89 - 97)

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