Lubricant circuit

Abstract

A lubricant circuit includes, but is not limited to a lubricant pump, which is connected on the suction side to a reservoir and on the pressure side to a distributor, at least one lubricating point, which is connected to the distributor and a return leading to the reservoir, and an electronic control unit, which is set up to regulate the output pressure of the lubricant pump by reference to the temperature of the lubricant.

Description

CROSS-REFERENCE TO RELATED APPLICATIONThis application claims priority to German Patent Application No. 102010019007.1, filed May 3, 2010, which is incorporated herein by reference in its entirety.TECHNICAL FIELDThe technical field relates to a lubricant circuit, in particular for the lubrication of an internal combustion engine such as an Otto or diesel engine in an automobile.BACKGROUNDSince the lubricant requirement of such an internal combustion engine increases with its speed, the lubricant circuit usually comprises a lubricant pump firmly coupled to an output shaft of the internal combustion engine and driven by means of this. As a result of this coupling, the throughput of the lubricant pump increases with the speed of the internal combustion engine. Since the lubricant throughput of the engine is not exactly linearly proportional to the rotational speed, but depends on other factors, in particular the temperature of the internal combustion engine, the lubricant pump must be ...

AI Technical Summary

Benefits of technology

A lubricant circuit, in particular for an internal combustion engine, comprising a lubricant pump, which is connected on the suction side to a reservoir and on the pressure side to a distributor, at least one lubricating point, which is connected to the distributor and a return leading to the reservoir, and an electronic control unit for controlling the operation of the pump, the control unit being set up to regulate the output pressure of the lubricant pump by reference to the temperature of the lubricant. Since the temperature of the lubricant can be determined even before starting the internal combustion engine, it is possible to suitably predefine a desired output pressure of the lubricant pump at the starting time of the internal combustion engine, so that pressure peaks at the output of the pump, which must conventionally be intercepted via the cold start valve, can be avoided a priori.

In order that the second actuator does not block the movement of housing and rotor toward one another when it is separated from the distributor by the valve, the valve is preferably designed as a directional valve, which in one position in which it separates the second actuator from the distributor, connects it to the reservoir. Whereas the first actuator is generally connected to a downstream portion of the distributor in order to ensure that a requisite pressure is reached there, the valve is preferably connected to an upstream portion of the distributor to enable a rapid response of the second actuator to pressure fluctuations at the output of the pump. This is particularly expedient if a throttle element, in particular a lubricant cooler and / or a lubricant filter, is disposed between the upstream and the downstream portion of the distributor, which effects a pressure drop from the upstream to the downstream portion and / or delays the dissemination of a high pressure from the output of the pump to the downstream portion.

Problems solved by technology

The cold start valve certainly offers effective protection from critically high pressures in the lubricant circuit but energy is lost uselessly every time that the cold start valve lets lubricant through.

Images