DE102004052137A1 - Coolant circuit for internal combustion engine has crankcase-coolant circuit and cylinder head-coolant circuit whereby they are implemented as separate coolant circuit and crankcase-coolant circuit is lockable with actuating element - Google Patents

Abstract

The coolant circuit (1) with crank case and a cylinder head comprises a crankcase-coolant circuit (2) and a cylinder head-coolant circuit (3) whereby they are implemented as separate coolant circuit and the crankcase-coolant circuit is lockable with an actuating element (14). A common inlet pipe (4) is arranged in the crank case.

Description

The The invention relates to a coolant circuit for one Internal combustion engine with the features of the preamble of the claim 1.

It starts from the German publication DE 100 47 080 A1 out. In this an internal combustion engine is described with a coolant circuit. The internal combustion engine includes a coolant pump that pumps coolant through a common supply line to a crankcase coolant circuit and to a cylinder head coolant circuit. In order to achieve the best possible heat distribution during operation in the internal combustion engine, the cylinder head and the crankcase have mutually corresponding openings in the cylinder head coolant circuit and in the crankcase coolant circuit. Through these corresponding openings coolant is conveyed from the crankcase coolant circuit in the cylinder head coolant circuit. The coolant flow rate is set by bores in the cylinder head gasket, which limit the cross section of the corresponding openings. In order to adjust the absolute coolant flow rates through the individual coolant circuits, the crankcase coolant circuit and the cylinder head coolant circuit are connected to one another via a further frontally arranged in the internal combustion engine opening. Furthermore, the flow rate of coolant with two thermally differently designed thermostatic valves can be controlled. As a result, the crankcase can be operated, for example, with an approximately 20 ° -30 ° C. higher coolant temperature than the cylinder head. By setting different temperatures in the crankcase and cylinder head, a quick warm-up of the engine is achieved, whereby the HC emissions are reduced. Further, in warmer operation of the crankcase, the internal friction can be reduced, whereby the wear is reduced and the life of the internal combustion engine is extended.

From Disadvantage of the proposed embodiment is the high structural Effort to achieve the advantages described.

task the present invention is to show simple means with which a generic coolant circuit for one Internal combustion engine can be represented.

These The object is achieved by the features in the characterizing part of the claim 1 solved by that the crankcase coolant circuit and the cylinder head coolant circuit are designed as separate coolant circuits and the crankcase coolant circuit can be closed with an actuating element.

In Advantageously, the coolant flow is not only through the crankcase coolant circuit reducible, but can be switched off. This results in a faster Heating the cylinder liners of the internal combustion engine after a Cold start and thus a minimization of friction in the cylinder liners while the engine warm-up, and a friction minimization in hot condition the internal combustion engine by increasing the cylinder liner temperature compared to a conventional cylinder liner cooling in Low load range, as known from the prior art. Due to the faster heating of the crankcase after a cold start, the HC emissions significantly reduced due to keeping the crankcase warm Minimized or switched off coolant supply, is further significantly reduces internal friction, thereby reducing fuel consumption Operation of the internal combustion engine is saved.

The Arrangement according to claim 2 allows a very compact arrangement of the coolant circuit.

by virtue of the embodiment according to claim 3, all cylinders are at about the same operating temperature held, causing distortions of the crankcase are minimized.

With the embodiment according to claim 4 is a particularly efficient cooling of the internal combustion engine achieved.

With an actuator according to claim 5 is a very accurate temperature control of the internal combustion engine possible.

With an actuator according to claim 6, a particularly robust and cost-effective variant is achieved.

in the The invention is based on a preferred embodiment closer in three figures explained.

1 shows schematically an inventive, reduced to the essential coolant circuit for an internal combustion engine;

2 shows a casting core of a crankcase coolant circuit according to the invention for an internal combustion engine;

3 shows a casting core of a cylinder head coolant circuit according to the invention for an internal combustion engine.

1 schematically shows an inventive, reduced to the essential coolant circuit 1 for an internal combustion engine with a crankcase and a cylinder head, consisting of a crankcase coolant circuit 2 , a cylinder head coolant circuit 3 , a common feed 4 and a coolant pump 7 , The coolant pump 7 promotes a coolant through the common inlet 4 in the crankcase coolant circuit 2 as well as in the cylinder head coolant circuit 3 , The outputs of the crankcase coolant circuit 2 and the cylinder head coolant circuit 3 return to the coolant circuit 1 through which the coolant from the coolant pump 7 is sucked again. The coolant flow direction is shown by arrows. According to the invention, the crankcase coolant circuit 2 and the cylinder head coolant circuit 3 designed as separate coolant circuits and the crankcase coolant circuit 2 is with an actuator 14 closable. The illustrated position corresponds to a locked crankcase coolant circuit. The crankcase coolant circuit 2 is completely located in the crankcase, the cylinder head coolant circuit 3 is in the crankcase, in the form of a distribution channel 3 ' and integrated the cylinder head.

2 shows a casting core for the crankcase coolant circuit 2 as well as the distribution channel 3 ' of the cylinder head coolant circuit 3 , The reference numerals of 1 apply to the same components also for 2 and 3 , The geometry of the casting core corresponds to the geometry of the coolant guides in an internal combustion engine. In a coolant pump room 10 becomes the coolant pump 7 arranged, their blades in a worm space 9 the coolant from a suction channel 8th , coming from a heat exchanger, not shown, suck and in the common inlet 4 promote. At the end of the common inflow 4 shares this in the separa th crankcase coolant circuit 2 and the cylinder head coolant circuit 3 on. Starting from the common inlet 4 flows around the coolant in the crankcase coolant circuit 2 all cylinders of the internal combustion engine and is through a crankcase outlet 11 discharged again.

Also starting from the common inlet 4 the coolant is parallel to the crankcase coolant circuit 2 in the cylinder head coolant circuit 3 promoted, first in the distribution channel 3 ' which is formed largely parallel to the longitudinal axis of the internal combustion engine and no connection to the crankcase coolant circuit 2 having. Starting from the distribution channel 3 ' the coolant continues to flow through branch channels 5 . 5 ' in corresponding branch channels 5 . 5 ' in the cylinder head. There flows through the coolant - as under 3 described - the cylinder head to then the cylinder head through a cylinder head exit 12 to leave. The flow direction of the coolant in the coolant inlet and outlet 8th . 11 . 12 , as well as in the branch channels 5 . 5 ' are each represented by arrows.

3 schematically shows the top view of a three-dimensionally illustrated casting core for the coolant circuit of the cylinder head coolant circuit 3 , At the, in the plane of the drawing behind the long side of the cylinder head are the to the branch channels 5 . 5 ' of the crankcase coolant circuit correspond to branch channels 5 . 5 ' of the cylinder head coolant circuit 3 arranged. Starting from the branch channels 5 . 5 ' The coolant flows through the cylinder head largely transversely to then in a collection channel 6 to be collected. The coolant leaves the cylinder head through one to the collection channel 6 arranged cylinder head exit 12 , The flow direction of the coolant is again indicated by arrows. Furthermore, axially extending projections are formed on the casting core, which are core supports 13 . 13 ' is.

In the proposed embodiment, the coolant circuit according to the invention 1 provided for a four-cylinder internal combustion engine, but can be used in any other internal combustion engine with any number of cylinders. Particularly preferred is the proposed coolant circuit 1 used in self-igniting internal combustion engines, of course, it can also be used in externally ignited internal combustion engines. As an actuating element 14 Preferably, a continuously adjustable valve is used, since hereby the most accurate temperature control of the crankcase and cylinder head is possible. The actuation of the control element 14 can be pneumatic, hydraulic or electromechanical. It can also switchable valves are used, which are particularly robust and cost-effective. The actuating element is preferred 14 in the crankcase outlet 11 arranged, but can at any point in the crankcase coolant circuit 2 be arranged.

The switchable flow behavior of the coolant through the crankcase of the internal combustion engine - from zero to maximum flow - with the actuator, a faster heating of the cylinder liner and thus a minimization of the piston sleeve friction in the engine warm-up and a friction minimization in hot condition by increasing the cylinder liner temperature compared to a conventional cylinder book vertical cooling achieved in the low load range. Advantageously, the HC emissions are minimized by the inventive design, especially during warm-up of the engine, at the same time the life of the internal combustion engine is extended.

1.

Coolant circuit

Second

Crankcase coolant circuit

Third

Cylinder head coolant circuit

3 '

distribution channel

4th

common Intake

5, 5 '.

Stichkanal

6th

collecting duct

7th

Coolant pump

8th.

suction

9th

auger

10th

Coolant pump room

11th

crankcase outlet

12th

Cylinder head outlet

13 13 '

chaplets

14

actuator

Claims (6)

Coolant circuit ( 1 ) for an internal combustion engine having a crankcase and a cylinder head, comprising at least one crankcase coolant circuit ( 2 ) and a cylinder head coolant circuit ( 3 ), wherein for both coolant circuits ( 2 . 3 ) a common coolant pump is provided, the two coolant circuits ( 2 . 3 ) by a common supply line ( 4 ) supplied with coolant, characterized in that the crankcase coolant circuit ( 2 ) and the cylinder head coolant circuit ( 3 ) are designed as separate coolant circuits and the crankcase coolant circuit ( 2 ) is closable with an actuating element. Internal combustion engine according to claim 1, characterized in that the common supply line ( 4 ) is arranged in the crankcase. Internal combustion engine according to claim 1 or 2, wherein the internal combustion engine has at least two cylinders, characterized in that the cylinders largely from the crankcase coolant circuit ( 2 ) are included. Internal combustion engine according to one of the claims 1 to 3 wherein the internal combustion engine has a longitudinal axis and the cylinder head coolant circuit ( 3 ) arranged in sections in the crankcase and through branch channels ( 5 ) is guided in the cylinder head, characterized in that the cylinder head coolant circuit ( 3 ) - is formed in the crankcase largely parallel to the longitudinal axis, - on a cylinder head side as at least two branch channels ( 5 . 5 ' ) is continued in the cylinder head, - largely for a transverse flow in the cylinder head to a second cylinder head longitudinal side and - along the second cylinder head longitudinal side as a collecting duct ( 6 ) is trained. Internal combustion engine according to one of the claims 1 to 4 , characterized in that the adjusting element is a continuously adjustable valve. Internal combustion engine according to one of the claims 1 to 4 , characterized in that the actuating element is a switchable valve.