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Various needle bearings and metal thrust washers are used in automatic transmissions (ATs and CVTs) for automobiles, however, in recent years thrust washers made of engineering plastics are begining to be adopted, because of their superiority in saving space, reducing weight and cost. This paper reports the newly developed low friction thrust washer made of engineering plastic for torque converters of AT·CVT.

This paper describes a new measurement method using fluorescence analysis to measure oil pump rates of radial lip seals for small shaft diameters. A test apparatus and operating procedure for measurement of pump rate were shown. First results of pump rates obtained with seals for 8 mm shaft diameter were shown. As a result, the oil pump rates under various shaft speeds and sump pressures ranged from 4 to 160 mg/h.

This paper describes one of fundamental remarks for perfect sealing, regarding the compatibility between a rubber compound and a lubricant. In the field, leakage occurred on rotary lip seals for grease-lubricated machinery. In most cases, the sealing lip had been hardened and deposition was found on the surface. In order to investigate the causes of the leakage, bench tests, pin-on-ring tests and observation tests were performed focusing on rubber and grease compounds. As a result, deposition similar to that occurred in the field was reproduced in specific cases. The results obtained suggested that a sort of solid MoDTC in grease would react with the fillers in rubber, causing surface deposition and leakage.

The effects of aromatic components in fuel on ignition and combustion of intermittent spray were examined experimentally. Four types of fuel with different aromatic components, and with similar cetane number and calorific value were used in this study. Fuels were injected into the high-temperature and high-pressure vessel with the injection pressures of 100 MPa and 60 MPa using an electronically controlled fuel injection system developed by the authors. Injection rate shaping applied to the experiments was rectangular, which is a typical injection rate shaping of a common rail type injection system. Images of spray flames were captured using an ICCD camera under ambient conditions corresponding to a turbo-charged diesel engine, 6.1 MPa and 1030 K. A two-color pyrometry technique was applied to the images of spray flame to quantify two-dimensional distributions of flame temperature and soot in flame.

In order to clarify the sealing mechanism of radial lip seals, a new test apparatus with a hollow glass shaft was developed, and the fluid behavior under sealing condition was observed by using the Laser Induced Fluorescent (LIF) method. In this paper, the description of the test apparatus and first measurement results are shown. A laser dye dissolved in synthetic oil below the seal lip was excited at a wavelength of 427nm by a SHG solid state blue light laser. The fluorescence was detected by a CCD camera through an optical filter. The fluid paths of the oil beneath the seal lip appeared ahead of each rib as soon as a shaft started to rotate. Furthermore, the intensity of the fluorescence, which is related to the fluid film thickness, increased with shaft speed increasing. First measurement results obtained with the LIF method were in good agreement with other measurement results.