Device and method for hydraulically controlling continuously variable transmission for vehicle

Abstract

This continuously variable transmission for a vehicle is provided with a transmission controller (12) for shifting gears in a variator (20) and an auxiliary gearshift mechanism (30), a line pressure regulating valve (11a), a primary pressure regulating valve (11b), and a secondary pressure regulating valve (11c). The transmission controller (12) is provided with a line pressure control unit (fig.4) that, when oil vibration occurs in the actual oil pressure at the primary pressure (Ppri) and / or secondary pressure (Psec), the line pressure (PL) is caused to exceed the line pressure (PL) beforeoil vibration occurred. The line pressure control unit (fig. 4) continues to increase the line pressure (PL) until gear shifting in the auxiliary gearshift mechanism (30) concludes in order to yield stable gear shifting when the gears are shifted in the auxiliary gearshift mechanism (30) with the line pressure (PL) in an increased state.

Description

technical field [0001] The present invention relates to an oil pressure control device and an oil pressure control method for a continuously variable transmission for a vehicle, in which a stepped transmission mechanism is provided in series with the continuously variable transmission mechanism, and the transmission oil pressure is controlled by a so-called double pressure regulation method. Background technique [0002] Conventionally, there is known a hydraulic control device for an automatic transmission that, in a continuously variable transmission based on a so-called monotonous pressure (line pressure=secondary pressure), changes the feedback of the feedback control when oil vibration occurs. Quantitative oil vibration countermeasures (for example, refer to Patent Document 1). [0003] In recent years, there has been a continuously variable transmission that is a so-called dual pressure regulating system (a system with pressure regulating valves for regulating the prim...

AI Technical Summary

Problems solved by technology

If the line pressure is continuously maintained, the fuel consumption rate will deteriorate

[0006] In this way, when the subtransmission mechanism is shifted while the line pressure is increased, it is necessary to reduce the increased line pressure. However, there is still room for improvement as to the timing of the reduction.

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