Browse Topic: Synchros

Items (193)

Development of an Assessment Methodology for synchronizer ring (CuZn Alloy) wear durability

2024-28-0185To be published on 12/05/2024

An optimized gear shift feeling throughout the life of a MT Gearbox is one of the major challenges during transmission development. Synchronizer ring’s function during its intended life play important role to get optimized gear shifting effort. Any undesired synchronizer ring (CuZn Alloy) wear causes high effort in gear engagement during vehicle running and discomfort to the driver. High wear rate reduces the life span on synchronizer ring. Current paper explains the experimental approach for study of critical parameters on synchronizer ring wear and Coefficient of friction (COF) under controlled temperature environment on test bench. Gear shift loading conditions based on Reflected Inertia (kgm2), shifting time (sec), shifting load (N) on gear knob and speed difference (rpm) between gears were calculated on synchronizer ring level and accordingly the loading conditions such as sliding speed (m/s), axial pressure (N/mm2) and synchro energy (J) were decided. As synchro wear rate and

Singh, Paramjeet, Yadav, Sanjay Kumar

SCREW, EXTERNALLY RELIEVED BODY (SYNCHRO), CRES (UNS S30200 OR UNS S30300

AS17184D (Current)

01/10/2024

E-25 General Standards for Aerospace and Propulsion Systems

Synchronizer Spring Failure Due to Gear Shift Loads - Investigation and Design Recommendations

2023-28-0051

11/10/2023

In manual transmission, the vital function of synchronizer pack is to synchronize the speed of the target gear for smooth gear shifting. The synchronizer pack consists of various elements and each of these elements has specific function. These elements are baulk rings, shifter sleeve, hub, synchro key, synchro springs etc. The function of synchronizer can be affected due to failure of any one of these elements. This work focuses on the failure of synchronizer pack due to synchro spring failure. The function of synchronizer spring is to exert the required force, to index the synchronizer ring before the movement of shifter sleeve over synchronizer ring. During the shifting of shifter sleeve from one gear to another gear, the springs deflect in both shifting directions. This causes fatigue failure of synchronizer springs. The manufacturing variations, and part quality issues results in very early fatigue failure of synchronizer springs. The failure of synchronizer springs affects the

JAMADADE, GAJANAN, K, Barathi Raja, Chatterjee, Soumik

Synchros, General Specification

AS20708C (Current)

06/05/2019

This specification relates to Synchros, 60 and 400 Hz. It is not complete in itself, but shall be used in conjunction with MIL-DTL-81963, in which the latter shall be recognized as forming an inherent part of this specification. This standard requires a Qualified Products List (see 6.4

AE-7A Generators and Controls Motors and Magnetic Devices

Counterfeit Electrical, Electronic, and Electromechanical (EEE) Parts; Avoidance, Detection, Mitigation, and Disposition

AS5553C (Historical)

03/26/2019

This standard is for use by organizations that procure and/or integrate and/or repair EEE parts and/or assemblies containing such items, including maintenance, repair, and overhaul (MRO) organizations. The requirements of this standard are generic and intended to be applied/flowed down, as applicable, through the supply chain, to all organizations that procure EEE parts and/or assemblies, regardless of type, size, and product provided. The mitigation of counterfeit EEE parts in this standard is risk-based, and these mitigation steps will vary depending on the criticality of the application, desired performance, and reliability of the equipment/hardware. The requirements of this document are intended to be used in conjunction with a higher-level quality standard (e.g., AS/EN/JISQ9100, ISO-9001, ANSI/ASQC E4, ASME NQA-1, AS9120, AS9003, and ISO/TS 16949 or equivalent) and other quality management system documents. They are not intended to stand alone, supersede, or cancel requirements

G-19 Counterfeit Electronic Parts Committee

Gearshift Quality Sensitivity Analysis

2019-26-0328

01/09/2019

Gearshift quality is a perceived quality parameter. Hence, is getting much importance because of the increased awareness about comfortable and refined driving experience, especially in the case of passenger cars. When the topic of gearshift feeling is broached in manual transmission vehicles, synchronizer pack (shifter sleeve, engaging gear, strut, synchronizer and gear synchro ring assembly) have been the focus point for optimization. Synchronizer type (single, double or triple cone), lining material, datch chamfer angle of shifter sleeve/synchro ring of gear/synchronizer, all of these have been extensively studied in the past to improve the gearshift quality. With stringent timelines for vehicle development, OEMs prefer to use off-the-shelf powertrain systems developed by powertrain manufacturers. Due to this, avenues to refine gearshift feel gets reduced to a large extent and hence refinement becomes difficult. The scope of this paper is to discuss gearshift quality parameters used

Patel, Hiral, Tendulkar, Vishveshvar, Baid, Himanshi, Bhosale, Vikas, Bhavikatti, Gururaj

SCREW, EXTERNALLY RELIEVED BODY, (SYNCHRO), CRES (UNS S30200 OR UNS S30300

AS17184C (Historical)

11/21/2018

E-25 General Standards for Aerospace and Propulsion Systems

Torsional Fluctuations Consideration while Design of Synchro Rings

2018-01-1823

09/10/2018

In today’s manual transmissions of car, gearshift system requires high performance with particular emphasis on low effort, minimal travel and positive feel. To meet these targets, a high capacity multi cone synchronizers along with higher co-efficient of friction material used for lower gears. The design of synchronizer with these specifications is influenced by torsional fluctuations from engine. Excessive torsional vibrations leads to wobbling of synchro rings within the peripheral clearances with surrounding parts. Wobbling leads to abrasion wear of frictional area of synchro ring causing grating or crashing noise of gears during shifting. This paper presents the optimization of the multiple cone synchronizer design exposed to excessive torsional vibrations and validation of the same on test bench during development stage instead vehicle level validation

Tawhare, Nitin, Aswale, Dhananjay, Ponkshe, Makarand