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Automobile OEM's around the world are looking to improve their overall vehicle and engine efficiency in terms of fuel economy and power output. Efficiency improvement is possible by cutting down the engine parasitic loads. One such parasitic load is the oil pump, which lubricates the engine parts. Oil pump is the heart of an engine lubrication system, and its important functions are cooling and lubricating the engine moving parts by delivering adequate oil flow based on the engine demand. Insufficient or no oil delivery from the oil pump leads to the seizure of the engine. The internal vane type oil pump is one kind of positive displacement type pump, where oil gets transferred from the oil sump into the inlet volume. The negative pressure is created inside the pumping chamber due to increase in area. As the vane rotates eccentrically with respect to the stator, it delivers the oil at a higher pressure from inlet to outlet and supplies to engine gallery through the discharge port.

Electronic closed loop control of automatic transmission functions can potentially benefit from the use of quantitative models of transmission response in a form compatible with controller design procedures. Transmission dynamic response during gear shifts of a discrete-ratio transmission is nonlinear. Procedures for developing linearized dynamic models are applied to the simulation of the nonlinear model of a representative power train during the inertia phase of a shift. The frequency responses for the resulting linear models are examined, and their implications for controller design are noted.

The technical advancements in microprocessors and their incorporation in motor vehicles has led to the feasibility of using continuously variable transmissions in automobiles. This paper discusses the design, development and testing of a rubber V-belt continuously variable transmission for a production vehicle. Overall speed ratios in excess of 7.0 were achieved with a hydraulically actuated driver sheave and a spring and cam loaded driven sheave. The drive was controlled with an 8-bit microprocessor which operated in three different control modes. The test results show that the rubber V-belt is viable for automotive use and has potential for improved fuel economy while maintaining good vehicle drivability.