Refine Your Search

Search Results

Viewing 1 to 8 of 8
Technical Paper

Analysis of the Influence of Pre-Loading in the Rating Life Calculation of Tapered Roller Bearings Applied to Lightweight Front-Axle Differentials

For intricate automotive systems that enclose several components, such as gearboxes, an important aspect of the design is defining the correct assembly parameters. A proper assembly can ensure optimized operating conditions and therefore the components can achieve a longer life. In the case of the support bearings applied to front-axle lightweight differentials, the assembly preload is a major aspect for an adequate performance of the system. During the design phase it is imperative to define reference values to this preload, so the application would endure its requirements. However, with the assistance of computer simulations, it is possible to determine an optimum condition of operation, i.e. optimum pre-load, which would increase the system reliability.
Technical Paper

Basic dynamic load rating analysis of Clutch Release Bearings

The design of Clutch Release Bearings (CRB) is usually based on angular contact ball bearings. This kind of bearings supports both axial and radial loads and the load limits depend directly on the contact angle. The CRB has its own particularity, since it is a radial angular contact ball bearing and its main load is on axial direction. Due to this special situation, this work is done to evaluate this CRB design according to the classical theory of bearing life calculation, developed by Lundberg and Palmgren (1947), which the standard ISO 281 is based on. The analysis is focused on the basic dynamic load rating of the bearing, which briefly means the expected load that the bearings support a life of 1 million cycles. This expectation follows a Weibull distribution with increasing failure ratio and a specific reliability.
Technical Paper

Evaluation of the Method of Failure Analysis in Angular Contact Bearings through the Envelope Technique

More efficient and more reliable methods to analyze the performance of the bearing test samples help to reduce validation time during development of rolling bearings. This paper presents a study of the impact on airborne noise and structural borne noise of especial prepared rolling bearings with angular contact submitted for durability tests. The study aims to link specific bearing failures to characteristics in airborne noise and structural borne noise using for instance the “envelope technique”. In the future these patterns will enable more effective online monitoring of failure evolution.
Technical Paper

Influence of Operating Parameters in Grease Loss of Rolling Bearing

The main purpose of the lubrication in the rolling bearing is to avoid and to reduce the metal to metal contact, thus it is possible to reduce the friction and to prevent the wear between the balls and the raceways. Consequently, the rolling bearing should work with grease or oil inside to guarantee an oil film between the balls and the raceways, thus this grease should stay inside the bearing. To avoid the grease loss the bearing normally may have a sealing but even so a little grease loss can occur. Hence the present investigation was initiated because of the need to understand a grease loss and the basic parameter that has influence on this. To help the elaboration of the experimental tests was used a DOE technique, thus it was possible to determinate simultaneously the individual and interactive effects of many factors that affect in the grease loss.
Technical Paper

Investigations on Friction Losses within Front End Accessory Drives

In order to increase the efficiency of internal combustion engines, Schaeffler Technologies recognized that it is necessary to identify the sources of energy losses, quantify such losses and to study ways to minimize them. Based on this premise, the Front End Accessory Drive parameters had to be investigated to locate where further potential enhancement is hidden. This paper aims to analyze and discuss about the main sources of energy losses occurring in FEAD and propose ways to optimize the system to the optimal range of efficiency and durability. Investigations showed that there are some loss points of the basic belt drive components which have good potential to be reducible, e.g., losses at bearings and belt.
Technical Paper

Self-Heating Test to Evaluate Temperature Stabilization in the Rolling Bearing

Heating generation in rolling bearings is a critical point for development and application, specially for heavy trucks. Several problems can occur in the rolling bearing and in the system when the temperature increases. For example, at high temperature levels the rubber sealing can change its proprieties and volume, creating a high interference at the contact with the rings. The grease can also be affected and modify its viscosity, generating a possible leakage, which is not allowed during life. This papers aims to study the heat generation and evaluate, experimentally, the temperature stabilization in clutch release bearings for heavy duty application. With this purpose, several tests were performed and the results were analyzed to find the main factors that can be influenced.
Technical Paper

Sensor of Position for Shifter Lever

Nowadays, the development of new technologies in the automobilist industry has increasing the incorporation of electronics into mechanic systems, what reflects on safer and more reliable mechanisms. This study will present the development of a sensor detent pin for the switchgear unit, which combines an electronic sensor to a detent pin, reducing the number of mechanic components as consequence. Its main function are the comprehension of shifting and selection movement and gear positions (neutral and reverse), as well as send these informations by means of electric signals to a central computer.
Technical Paper

Study of the Swelling in Lip Seal Application

There are large numbers of variables that affect seal performance, for example, temperature, grease and dusty. This paper aims the study one of these variables, the swelling. Swelling is the absorption of the liquid by the rubber and this liquid absorption can deeply alter physical and chemical properties and hence change tensile strength, extensibility and hardness of the rubber. A review about seal and the characteristics of the seal performance will be made and also a study about what this phenomenon affects the seal performance. Thus the purpose of the present paper is to develop the conception of swelling by investigating the characteristics of swelling deformation.