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Mechanical seals have been applied as sealing devices for water pumps of automotive engines. The mechanical seal plays an important state. Therefore, there are many kinds of constructions. This paper is concerned with the FEM (Finite Element Method) analytical results for various water pump seal construction. It becomes clear that the property of heat transfer is closely related to the sealing durability.

A C-shaped seals is used under severe conditions in which rubber gasket and o-ring can not be used. Furthermore, C-seals exhibit various advantage such as small fitting space and light weight, therefore widely used as sealing elements for rocket engines and automotive engines. And also particular advantage offered by C-seals is good springback, high level of sealing performance under high pressure condition, stretching of the flange bolts. This paper is concerned of the sealing mechanism of C-seal by experimental work and finite element stress analysis. As a result, the lead coated layer on a C-seal has an important function on the sealing performance. In the present paper we describe on an interesting results reached by experiments regarding correlation of helium leakage late and contact pressure.

Mechanical seals have been applied as a sealing device for an automotive air conditioning compressor. Sometimes, the leaking trouble occurs under the conditions such as excessive wear, blistering formation and cracking phenomena on the carbon-ring. This paper is concerned with the analysis of cracking phenomena based upon Finite Element Method (FEM) calculation and experimental investigation.

Instead of end-face type seals, lip-type seals have recently been widely applied as sealing devices for automotive air conditioning compressors, and have shown good sealing performance in practical applications. This paper is concerned with the sealing phenomena of lip-type seals, which run under hydrodynamic lubrication between the lip/shaft surfaces.

C-shaped metal seals (C-seal) are used as static seals under the conditions such as high vacuum, high pressure, high temperature and cryogenic states. The correlation between the sealing performance and design parameters as loading force, deformation, and the surface roughness of ontacting faces have been investigated. This paper is concerned with the relationship between the surface condition of the coated-lead layer of C-seals and the surface roughness of mating flange. The effects of surface condition on leakage are examined fundamentally. Annular coated-lead layer on the surface of a C-seal prevents leakage, though there exist the fine defects or surface irregularities on the flange. It becomes clear from the test results that the surface conditions of the flange and loading force closely relate to the leakage rates with the deflection of C-seal under the. load and the behavior of the contact condition of flange surface.

Mechanical seals have been applied as a sealing device for an automotive air conditioning compressor. However, the leaking trouble occurs under the conditions such as excessive wear, blistering formation and cracking phenomena on the carbon-rings. This paper is concerned with a study of carbon-cracking phenomena.

The turbo-charger of an automotive engine is commonly used for increasing its power characteristics. In this equipment, both sealing and lubricating conditions are important factors and face to difficult technical problems. This paper is concerned with sealing problem for the turbo-charger, and development of low frictional type mechanical seals with good performance and excellent reliability.

The adoption of the newly developed self-standing grid construction allows a more flexible layout of the electrodes and location of the grids, while reducing the number of grid leads. These improvements make it possible to minimize the lead pitch and to increase the flexibility of the lead out position. For example, the leads of the new clip-on type displays will allow them to be condensed on one side of the display, while in the case of the ordinary Vacuum Fluorescent Displays (VFDs) the leads are located on both the top and the bottom. By connecting flat cables to the minimized leads, a clip-on VFD was successfully developed, which is excellent in terms of mounting flexibility, circuit maintenance, system cost and function. The manufacturing process and features of the clip-on VFD will be described later.

A lip seal for use in high-pressure automotive air conditioning compressors has been developed. This paper describes the design and the sealing performance of this new lip seal.

The mechanical seal in automotive water pumps is critical to the performance and reliability of the engine, requiring consistent, effective sealing performance and long operating life. In recent years, the advent of maintenance free performance requirements and increasingly severe operating conditions have resulted in significant changes to the variety and concentration of additives in cooling systems. As a consequence of these changes to the additives, various types of premature seal leakage failures have occurred during service operation. These have been categorized into four types of failure modes and compared with seals providing normal service in order to establish simulated test conditions for engine coolants containing various additives. This paper reports on the various types of failure mechanisms that were found to occur during simulated performance testing and the corrective measures that will eliminate their occurrence

To produce high quality appearance interior parts, precise pattern forming or gloss reduction of three-dimensional door trim cover materials are utilized. In the preparation of formed trim cover using polyvinyl chloride (PVC), prior pattern forming on original cover material or post-pattern forming with vacuum forming dies are employed. In the latter case, the die is usually made of epoxy resin. Although vacuum holes are prepared on the resin die as necessary, the lack of uniformity in air permeability causes inferior pattern transferability. In this development, special porous ceramic die is used as die material so that trim cover material can be evenly sucked through the fine pores on its surface. As a result, a door trim forming die of superior pattern transferability has realized.

There are various types of super chargers applied for mechanical charging system. Root system is the typical one of them, comprising some varieties such as vane type, spiral type, lysholm type, etc., each of which contains problems of consuming power, heat generation, wear- or other. It is now a big issue for the industry to overcome such problems and this paper refers to the effect of the vane type super charger (ESC-300) which could minimize such problems as less as possible.

End-face type seals (mechanical seals) have been applied as a sealing device for the automotive air conditioning compressor. However, in the practical market, oil or gas leakage from sealing devices sometimes occures based on blistering phenomena of carbon piece and lubricating conditions between rubbing surfaces. The paper presents good sealing performance for the developed face type mechanical seals.

On behalf of a face-type seal (mechanical seal), a new lip type seal for an automotive air conditioning compressor was developed. The paper presents good sealing performance and fundamental of designing for the new seal.

According to the 1982 Japanese Engine Data Book, 249 automobile engine models are used, including gasoline and diesel engines. Among them, 87 models (approximately 60% of all 4-cycle gasoline engine models), are designed for small passenger car applications, with displacements between 1.51 and 2.00. This paper will highlight the area such as Seals for Automobile Engine Applications, Present Automotive Engine Seal Situation in Japan and Countermeasure Activity for Field Claims.

It is clear that excessive lip wear is one of the origin of oil seal leakage in the market. In this paper, follows are discussed; Oil seals used for the rear side of automotive mission gear case have excessive lip wear as typical failure mode, and the sealing characteristics of oil seals is influenced by reciprocating motion of rotational shaft with rough surface.

Improvement of automotive fuel consumption is subject of saving energy today. Oil seals with low friction for automobile are required in the market. In this report, an idea for decreasing the friction of seals and its concreate countermeasure are discussed. It becomes clear that developed low friction seals have good sealing performance as same as present seals.

Types of boot seals for rack and pinion gear of automotive steering and their characteristics are given, and necessary items for designing seals are clarified based on experiments and experiences upon required performances of products.

Types of oil seals for automotive shock absorbers and their characteristics are given, and necessary items for designing seals are clarified based on experiments and experiences upon required performances of products.

In order to improve the reliability of seals for automotive application in practical use, it is considered that further basic investigations concerning sealing characteristics of seals are necessary. However, it has been found, from analyzing seals decided in the market as defective parts, that the troubles of seals in the market are mainly caused by both wrong handling for seals and the use under wrong operating condition which has not been expected by manufacturers of seals. Therefore, in order to improve the reliability of seals, it is important to investigate in detail troubles on functional characteristics of seals and their countermeasures. In this paper, on oil seals, O-rings, water pump seals and dust cover seals as seals for automotive application, the results of investigations are discussed.