scholarly journals Slip at Vehicle Transmission System with Hydrokinetic Converter in the Urban Test Cycle

2019 ◽  
Vol 26 (4) ◽  
pp. 21-28
Author(s):  
Andrzej Bieniek ◽  
Jarosław Mamala ◽  
Krzysztof Prażnowski ◽  
Mariusz Graba
Keyword(s):  
Automatic Transmission ◽  
System Optimization ◽  
Torque Converter ◽  
Transmission System ◽  
Transmission Systems ◽  
Factors Affecting ◽  
Driving Cycles ◽  
Harmful Emissions ◽  
The One ◽  
Slip Phenomenon

AbstractThe study concentrated on slip phenomenon occurring at hydrokinetic converter in passenger car transmission system. Optimization of modern automatic transmission systems aims, on the one hand, to further increase the comfort of use, and on the other hand to improve the efficiency and reliability operation of individual components, in such a way as to ultimately result in lowering fuel consumption and also harmful emissions. One of the important factors affecting the mentioned transmissions properties as a whole system is the slip phenomenon occurring between the pump and the hydrokinetic converter turbine. The study presents the results of research on ZF 4HP20 and Fuji Hyper M6 gearboxes operating in vehicle transmission systems. The tests were carried out using the MAHA MSR 500 chassis dynamometer during driving at chosen test cycles. The research covered the transmission systems operating according to selected control algorithms affecting not only the gear shifting strategy but also the operation of the lock up clutch causing the transmissions slip values. As shown by the conducted research, the algorithm controlling the operation of the torque converter can have a significant influence on their operating indexes. The conducted analyses indicate the possibilities of improving the transmission operating indexes, especially in urban driving cycles.

Hydrodynamic Torque Converters in Mechanical Transmission Systems: Methods and Analysis

1994 ◽  
Author(s):  
Anders Hedman
Keyword(s):  
Linear Equations ◽  
Equation System ◽  
Torque Converter ◽  
Transmission System ◽  
Mechanical Transmission ◽  
Transmission Systems ◽  
Linear Relationships ◽  
Non Linear ◽  
Computer Calculations ◽  
System Power

Methods for analysis of general mechanical transmission systems with a hydrodynamic torque converter (HTC) are presented. The methods are adapted for computer calculations. The properties of the HTC must be known, either explicitly as speed and torque characteristics, or implicitly as internal geometry (blade angles, etc.). Linear relationships between the torques and between the speeds of the shafts of the transmission system (except the HTC) are easily formulated. The HTC has coupled, non-linear, relationships for torques and speeds. Different ways of including these non-linear equations are presented. This can be implemented in a computer program. Solving the equation system yields the torque and speed of each shaft of the transmission system. Power losses can be handled.

Dynamic Model of Automatic Transmission System of Tracked Vehicle

2013 ◽  
Vol 397-400 ◽  
pp. 369-373 ◽  
Author(s):  
Jun Yi ◽  
Shui Sheng Chen ◽  
Da Zhang You
Keyword(s):  
Regression Analysis ◽  
Dynamic Model ◽  
Intelligent Control ◽  
Automatic Transmission ◽  
Torque Converter ◽  
Transmission System ◽  
Simulation System ◽  
Tracked Vehicle ◽  
Planetary Transmission ◽  
Test Result

The dynamic characteristic of automatic transmission system of tracked vehicle was thorough analyzed. The primary characteristic of torque converter was proposed by means of regression analysis of test result. The dynamic model of three-freedom planetary transmission was constituted using drive principles of planetary transmission. Thus the foundation of intelligent control and simulation system of automatic transmission of tracked vehicle was established.

Modelling of dynamic characteristics of an automatic transmission during shift changes

2002 ◽  
Vol 216 (4) ◽  
pp. 331-341 ◽  
Author(s):  
N Zhang ◽  
D K Liu ◽  
J M Jeyakumaran ◽  
L Villanueva
Keyword(s):  
Dynamic Characteristics ◽  
Hydraulic System ◽  
Model Simulation ◽  
Automatic Transmission ◽  
Torque Converter ◽  
Transmission System ◽  
Simulation System ◽  
Transient Dynamics ◽  
Output Torque ◽  
System Module

This paper describes modelling of the transient dynamics of an automatic transmission during gear changes. A brief introduction to the automatic transmission system and the dynamic characteristics of the transmission components during the gear changes are presented. Then, detailed mathematical models of a four-speed automatic transmission manufactured by BTR Automotive, Australia, are developed. A mode description method is used to describe the transient shifting process and a modular structure of the transmission system, which consists of a torque converter module, geartrain module, hydraulic system module and modules of clutches and bands, is presented. As an application, the developed simulation system is applied to investigate the transient performance of the automatic transmission during the 1–2 shift process. The output torque profiles predicted by the model simulation correlate very well with the experimental data measured from vehicle tests.

scholarly journals Advanced Power Transmission System

2012 ◽  
Vol 23 (2) ◽  
pp. 191-207
Author(s):  
Rafea M. Abd El-Maksoud Rafea M. Abd El-Maksoud
Keyword(s):  
High Performance ◽  
Power Transmission ◽  
Automatic Transmission ◽  
Planetary Gear ◽  
Torque Converter ◽  
Transmission System ◽  
Present System ◽  
Power Splitting ◽  
Operating Modes ◽  
Power Transmission System

Different researches are adopted to modify and enhance automatic transmission by every means. Whereas, torque converter that represents the most important component in such transmission suffers from some problems that are not completely solved. In this paper, power transmission system is herein introduced as a unique power transmission system that is not affected by torque converter problems. This power transmission operates with power splitting concept and is composed of conventional torque converter connected to planetary sets. Three clutches are used to shift the operating modes and unique positive displacement hydraulic couplings are utilized to regulate performance in power paths. Also, a modified model used to predict torque converter performance is utilized with planetary gear kinetics to assess the transmission performance. Moreover, the present system operates with high performance. Unlike the automatic transmission that operates in line, the present system operates with infinity number of operational bands for each engine speed.

scholarly journals An optimized observer for estimating torque converter characteristics for vehicles with automatic transmission

2018 ◽  
Vol 7 (2) ◽  
pp. 573
Author(s):  
Niresh J ◽  
Kirubakaran R ◽  
Mohana Praddeesh M ◽  
Gokul V ◽  
Gokkul T
Keyword(s):  
Internal State ◽  
Automatic Transmission ◽  
Torque Converter ◽  
Transmission System ◽  
Power Train ◽  
State Space Analysis ◽  
Internal States ◽  
Real Time Information ◽  
Time Information ◽  
Train System

The trending technology in the automobile power train system is the automatic transmission which allows the driver to drive the vehicle without pressing the clutch and can make gear shifting decisions themselves and thus frees the driver from shifting the gears manually. The system consists of torque convertor which replaces clutch and an alternate transmission system which consisting of planetary gears and actuators as drivetrain. In spite of the advantages of the automatic transmission system, there is a problem developing a controller for the system. That is because of the fact that the parameters characterizing the performance of the power train are not measurable because of sensor cost and reliability considerations. There is a need to provide real time information about the un-measurable parameters especially the internal state parameters of the torque converter. Thus, this paves the way for the development of model-based estimation for automatic transmission system to improve the fuel economy during the whole driving profile. The state space analysis can aid in the process. Several outputs from the system can be measured and can be used as a model for observing the internal states of the torque converter system. For this analysis MATLAB/Simulink can be used to model the plant and tools available in MATLAB can aid in developing a specific “state observer” which is the means in which the states can be studied.

Discuss BMW Automatic Transmission Work Principle and Fault Handling

2013 ◽  
Vol 273 ◽  
pp. 240-244
Author(s):  
Chao Chen
Keyword(s):  
Automatic Transmission ◽  
Torque Converter ◽  
Transmission System ◽  
Gear Transmission ◽  
Hydraulic Control ◽  
Transmission Control ◽  
Manual Gearbox ◽  
Fault Handling ◽  
Gear Transmission System ◽  
Fluid Coupling

The structure of the automatic transmission is slightly complicated than the manual gearbox, but its function has increased greatly. Classification, automatic transmission control of the gear transmission system can be divided into hydraulic control hydraulic automatic transmission and electronically controlled hydraulic automatic transmission, hydraulic transmission device can be divided into the structure of the fluid coupling and torque converter, combined with the above the structure and principle of a BMW to analyze automatic transmission failure and treatment.

Optimal parameters design method for power reflux hydro-mechanical transmission system

2018 ◽  
Vol 233 (3) ◽  
pp. 585-594 ◽  
Author(s):  
Qiao Zhang ◽  
Dongye Sun ◽  
Datong Qin
Keyword(s):  
High Efficiency ◽  
Automatic Transmission ◽  
Planetary Gear ◽  
Torque Converter ◽  
Transmission System ◽  
Speed Ratio ◽  
Structural Parameter ◽  
Mechanical Transmission ◽  
Power Performance ◽  
Starting Torque

To ensure the starting torque ratio while improving the efficiency of the automatic transmission system, a power reflux hydro-mechanical transmission system which consists of a torque converter, a planetary gear, and two gearboxes is proposed. First, the properties of the speed ratio, torque ratio, efficiency, and capacity in the power reflux hydro-mechanical transmission system are modeled. Then, the non-dominated sorting genetic algorithm II is used to optimize the structural parameter of the planetary gear and the speed ratio of the gearbox T1, with the speed ratio width in the high-efficiency area, efficiency, and power performance acting as target functions. Moreover, the method of selecting the specific torque converter for the power reflux hydro-mechanical transmission system is proposed. Results show that the starting torque ratio of the power reflux hydro-mechanical transmission system increases to 4.87 and the equivalent efficiency in high-efficiency area of the power reflux hydro-mechanical transmission system reaches to 90.87%. Therefore, the power reflux hydro-mechanical transmission system can reach higher efficiency while ensuring the starting torque ratio compared with hydro-mechanical power split transmission, which can significantly reduce fuel consumption once applied to the construction vehicle.

Unfilled Training Positions in Germany – Regional and Establishment-Specific Determinants

2019 ◽  
Vol 239 (4) ◽  
pp. 661-701 ◽  
Author(s):  
Sandra Dummert ◽  
Ute Leber ◽  
Barbara Schwengler
Keyword(s):  
Related Factors ◽  
Factors Affecting ◽  
External Conditions ◽  
Western Germany ◽  
Enterprise Level ◽  
Specific Factors ◽  
Regional Factors ◽  
The One ◽  
Training Position ◽  
Quantitative Importance

AbstractThe current situation in the German apprenticeship market is characterized by two contradictory developments. On the one hand, establishments are experiencing increasing problems filling the training positions they offer, and the number of vacant training positions is climbing. On the other hand, the transition into training is still difficult for many young people, and the number of unsuccessful vocational training applicants is rising. Hence, matching supply with demand is becoming increasingly difficult in the German job market for training positions. Using the Linked Employer-Employee dataset (LIAB) from the Institute for Employment Research (IAB), our paper provides a closer examination of the phenomenon of unfilled training positions. It presents an overview of the evolution of vacant training positions in eastern and western Germany and attempts to explain the number of vacancies by investigating the factors responsible for the establishments’ inability to fill their training positions. We assume that training position vacancies are due not only to internal company reasons such as firm size or the wage offer for apprentices but also to external conditions such as general regional factors. Therefore, our analysis also considers the situation on the demand side of the labor market within a region. The results of our multilevel mixed-effects estimations show that in addition to characteristics on the enterprise level, regional determinants also affect the share of vacant apprenticeships. With respect to establishment-related factors, mainly characteristics that describe the attractiveness of the firm prove to be important. With regard to regional-specific factors, we find that the availability of school leavers in a region in addition to the level of regional-sectoral competition impacts the recruiting success of establishments. Our analysis also shows that there are remarkable differences between eastern and western Germany concerning both the quantitative importance of unfilled training positions and the factors affecting them.

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