Oil pump device

Abstract

If a vehicle starts off after an engine idle stop, an auxiliary pump is switched on and delivers oil until the main oil pump driven by the engine delivers an sufficient amount of oil. If at this point the suction pipe is not emerged in the oil reservoir, e.g. during a stop on an uphill road, the suction pipe runs empty and is filled with air only. Thus, the auxiliary pump is unable to deliver oil. The invention provides a siphon-like pipe with a reservoir which does not run empty during tilt: An oil pump apparatus for supplying an oil to a vehicular transmission includes a pump (2) to suck the oil from an oil reservoir (18) through an inlet port into a pumping chamber, and an intake circuit (5) to convey the oil sucked from the oil reservoir (18) to the inlet port. The intake circuit (5) includes a proximal segment (51), an intermediate segment (52) and a distal segment (53). The proximal segment (51 ) extends from the inlet port, to the intermediate segment (52). The intermediate segment (52) extends upwards from the proximal segment (51). The distal segment (53) extends downwards from a first connecting end portion (53b) connected with the intermediate segment (52) to a end portion formed with a suction opening (53a) to suck the oil from the oil reservoir (18).

Description

technical field [0001] The present invention relates to an oil pump device for supplying oil required for a vehicle transmission. Background technique [0002] Conventionally, Patent Document 1 discloses a configuration including a main oil pump driven by an engine and an auxiliary oil pump driven by a differential gear. Furthermore, the suction port of the auxiliary oil pump is arranged at a position higher than the suction position of the main oil pump so that the auxiliary oil pump does not function during normal running. In this way, it is configured that the main oil pump functions and when the oil level drops, at least a part of the suction port of the auxiliary oil pump is located above the oil level so that it does not function as an oil pump, thereby excluding power from the auxiliary oil pump. loss. [0003] Patent Document 1: (Japanese) Unexamined Patent Publication No. 2001-165286 [0004] However, in the technology described in Patent Document 1, since the su...

AI Technical Summary

Problems solved by technology

[0004] However, in the technology described in Patent Document 1, since the suction port of the auxiliary oil pump is opened to the atmosphere, the oil in the suction path drops, and air may accumulate in the auxiliary oil pump and the suction circuit of the auxiliary oil pump.

In this way, in the state where air is accumulated in the suction circuit, even if the auxiliary oil pump is operated as needed, it takes time until the required oil pressure is obtained, and there is a problem that the required oil pressure cannot be supplied to the transmission.

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