scholarly journals Electro-mechanical Transmission Ratio Shifter of Rubber Belt Continuously Variable Transmission for Motorcycle Applications

2019 ◽  
Vol 1273 ◽  
pp. 012071
Author(s):  
Bambang Supriyo ◽  
Sugeng Ariyono ◽  
Bambang Tjahjono ◽  
Bambang Sumiyarso
Keyword(s):  
Continuously Variable Transmission ◽  
Transmission Ratio ◽  
Mechanical Transmission ◽  
Variable Transmission ◽  
Rubber Belt

On the design and tuning of the controllers in a power-split continuously variable transmission for agricultural tractors

2003 ◽  
Vol 217 (8) ◽  
pp. 745-759 ◽  
Author(s):  
S M Savaresi ◽  
F Taroni ◽  
F Prevedi ◽  
S Bittanti
Keyword(s):  
High Efficiency ◽  
Continuously Variable Transmission ◽  
System Structure ◽  
Transmission Ratio ◽  
Mechanical Transmission ◽  
Power Split ◽  
Variable Transmission ◽  
Servo Controller ◽  
Automatic Controllers ◽  
Agricultural Tractors

In this work, a power-split continuously variable transmission (CVT) used in high-power tractors is considered. Power-split CVTs are characterized by the combination of a traditional discontinuous mechanical transmission and a continuously variable transmission. This provides, at the same time, smooth variations of the transmission ratio and high efficiency of the overall transmission system. The CVT considered in this paper is a hydrostatic power-split unit conceived for top-power agricultural tractors. The goal of this paper is to present a case study on the design and tuning of the control system structure for this type of CVT. This structure consists of three main parts: a servo controller on the internal current of the valve of the hydraulic transmission; a servo controller on the hydraulic transmission ratio; a synchronizer which coordinates the hydraulic and the mechanical parts of the CVT. The design, tuning and testing of this set of automatic controllers is presented.

Improving the Efficiency of a Compact Inline Hydro-Mechanical Transmission (i-HMT) at Lock-Up

2021 ◽  
Author(s):  
Johnathan (Hans) Barkei ◽  
Perry Y. Li
Keyword(s):  
Planetary Gear ◽  
Continuously Variable Transmission ◽  
Transmission Ratio ◽  
Mechanical Transmission ◽  
Operating Condition ◽  
Hydrostatic Transmission ◽  
Variable Transmission ◽  
Low Efficiency ◽  
Opening And Closing ◽  
Efficient Transmission

Abstract A hydro-mechanical transmission (HMT) transmits power both mechanically and hydraulically allowing continuously variable transmission ratios and more efficient transmission than hydrostatic transmission. A conventional HMT tends to be costly and bulky since it has a hydrostatic transmission in parallel with a mechanical transmission. An alternative is a compact inline configuration that utilizes a two-shafted pump that is mechanically and hydraulically connected to a motor. This avoids the need for a planetary gear set while providing the HMT functionality. When the pump/motor displacement is zero, all of the power is transmitted mechanically and the transmission ratio is unity, a condition referred to as lock-up that is expected to be very efficient. Previous research however has shown significant losses at this operating condition in experiments. This is thought to be caused primarily by compressibility losses due to the repeated unnecessary opening and closing of the distributor valves. This paper first models the Hondamatic in simulations to confirm that compressibility losses contribute to the low efficiency at lock-up. Second, the paper proposes a solution to reduce these compressibility losses by means of a second cam mode that closes the distributor valves to prevent flow between the piston and the high and low pressure volumes. The performance of the existing inline HMT and the proposed solution at lock-up are modeled in simulations and compared. The results indicate a 10% increase in efficiency at lock-up.

Transmission ratio calibration for electro-mechanically actuated continuously variable transmission

2017 ◽  
Vol 7 (3) ◽  
pp. 127
Author(s):  
Izhari Izmi Mazali ◽  
Kamarul Baharin Tawi ◽  
Bambang Supriyo ◽  
Nurulakmar Abu Husain ◽  
Mohd Salman Che Kob ◽  
...  
Keyword(s):  
Continuously Variable Transmission ◽  
Transmission Ratio ◽  
Variable Transmission

Research on Pulley Strain of Metal Belt CVT

2014 ◽  
Vol 952 ◽  
pp. 249-252
Author(s):  
Wu Zhang ◽  
Wei Guo ◽  
Fa Rong Kou ◽  
Yi Zhi Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Analytical Method ◽  
Compressive Strain ◽  
Continuously Variable Transmission ◽  
Transmission Ratio ◽  
Element Analysis ◽  
Variable Transmission

Pulley strain aggravated whole-Part abrasion, affected friction and lubricates state of metal belt continuously variable transmission. Pulley strain was analyzed by analytical method and finite element analysis. The results indicate that with the increase of transmission ratio, the driver pulley compressive strain is increases after reduces for a while, and the driven pulley increase. Compressive strain dense when radius is lesser and vice versa. Two methods results are basically the same, whereby demonstrating that the model is rational and that the analysis results are reliable.

scholarly journals Design Principles and Traction Performance of a Novel Zero-spin Rolling Conical Traction Continuously Variable Transmission

2020 ◽  
Author(s):  
Chao Li ◽  
Xiuquan Cao ◽  
Qing-tao Li
Keyword(s):  
Numerical Model ◽  
Computational Models ◽  
Design Principles ◽  
Transmission Efficiency ◽  
Continuously Variable Transmission ◽  
Transmission Ratio ◽  
Variable Transmission ◽  
Contact Models ◽  
Spin Momentum

Abstract In the existing traction continuously variable transmission (CVT), half toroidal CVT (HT-CVT) is considered to have a better traction performance. However, the HT-CVT has the spin losses due to its structural limitations, which significantly influences the traction efficiency. In this paper, the kinematic qualities and contact models of a novel zero-spin rolling conical CVT (RC-CVT) are studied, and then the rollers and conical disks are compactly designed through the proposed design principles. Subsequently, the transmission efficiency is investigated by using a detailed numerical model and compared with HT-CVT. Based on these computational models and parameters, the practical spin ratio, spin momentum and traction efficiency of RC-CVT are calculated and compared with HT-CVT. The results show that the practical spin ratio and spin momentum of RC-CVT are much smaller than that of HT-CVT, and the efficiency on fixed transmission ratio is consequently higher than that of HT-CVT.

scholarly journals Analysis and experiment of HMT stationary shift control considering the effect of oil bulk modulus

2020 ◽  
Vol 12 (11) ◽  
pp. 168781402096832
Author(s):  
Xueliang Li ◽  
Lu Zhang ◽  
Shujun Yang ◽  
Nan Liu
Keyword(s):  
Experimental Study ◽  
Bulk Modulus ◽  
Control Method ◽  
Simulation Analysis ◽  
Continuously Variable Transmission ◽  
Mechanical Transmission ◽  
Reverse Time ◽  
Shift Quality ◽  
Shift Control ◽  
Variable Transmission

In order to improve the shift quality of hydro-mechanical continuously variable transmission, the effect of tangent bulk modulus and different control methods on the shift quality were analyzed. Theoretical analysis and experimental study on the tangent bulk modulus of oil were carried out to obtain the effect law of air content on the tangent bulk modulus of oil. A four-cavity model of a closed hydraulic circuit was established based on a two-stage arithmetic type hydro-mechanical transmission. By means of simulation analysis and experimental study, the effect of the tangent bulk modulus of oil on the shift quality is studied. The lean control method of reasonably controlling displacement ratio and prolonging the reverse time of load torque is put forward. The results show that this method can reduce the fluctuations of the speed of the fixed displacement motor and the oil pressure of the original low-pressure side. This method can also improve the shift quality and provide reference for the study of the shift process of hydro-mechanical continuously variable transmission.

The Optimization of Engine Transmission Matching Reduces Car Fuel Consumption

1980 ◽  
Author(s):  
P. Castelli ◽  
L. Morello
Keyword(s):  
Fuel Consumption ◽  
Research Program ◽  
Research Council ◽  
Automatic Transmission ◽  
National Research Council ◽  
Continuously Variable Transmission ◽  
Italian National Research Council ◽  
Variable Transmission ◽  
Rubber Belt

The advantages offered by a continuously variable transmission are briefly indicated The rubber-belt, electronically controlled, automatic transmission designed and built by Fiat in the frame of a Research program financed by the Italian National Research Council is described. The performance and fuel consumption results of the prototype equipped with this transmission are compared with the corresponding results of the conventional car.

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