Search Results

Upgrading of the performance and the durability of bellow boots used to seal constant-velocity joints are essential to seet the demand for higher performance and longer life automobiles. In this discussion about bellows boots for sealing constant-velocity joints, examples and analysis results of bench tests for studying wear and fatigue durability are presented.

We have developed a diaphragm which has low gas permeability and is used in the accumulator for the automotive hydraulic brake system, adopting the sandwich structure of rubber and resin films. Improvement of the diaphragm's gas permeability is absolutely necessary to achieve a maintenance-free and also light-weight and small-sized accumulator used for the automotive hydraulic brake system. We will discuss the development of the new resin films and investigation of the design factors of the accumulator focusing on the low gas permeability and durability under low temperature conditions.

In a diaphragm used for an accumulator, the relationship between design factors and durability in low temperature is discussed from the occurrence of buckling phenomenon through the observation results. The durability of the diaphragm which has a sandwich structure of rubber and resin films, is greatly influenced by the buckling phenomenon which occurs during deformation of the diaphragm when used for an accumulator in low temperature condition.

Regarding the polyester thermoplastic Elastomer (TPEE) boot used in a Constant Velocity joint(CVJ), it is effective to adopt soft and low frictional coefficient (μ) TPEE material which achieves compact size, low frictional noise and easy assembling. However, in the conventional low hardness TPEE, both grease resistance and heat resistance deteriorate, so it was necessary to improve the structure of TPEE polymers. We developed the new soft TPEE CVJ boot, focusing on the improvement method of TPEE polymers and design factors to achieve the compact and low frictional noise boot.