EP1299624A1

EP1299624A1 - Device for cooling an internal combustion engine

Info

Publication number: EP1299624A1
Application number: EP01955216A
Authority: EP
Inventors: Manfred Schmitt
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2000-07-01
Filing date: 2001-06-28
Publication date: 2003-04-09
Anticipated expiration: 2021-06-28
Also published as: JP2004502083A; US20030000487A1; DE50110945D1; EP1299624B1; DE10032184A1; WO2002002917A1

Abstract

The invention relates to a device (10) for cooling an internal combustion engine (11), preferably a four-cylinder engine, comprising coolant connections (13, 13', 14, 14'; 17, 17' - 24, 24') to a coolant circuit provided on the internal combustion engine (11), said coolant connections being connected to at least one cooling jacket region (12', 12'', 12''') of the internal combustion engine (11). According to the invention, a group of inlets (17 - 24) and outlets (17' - 24') that are arranged in pairs, each having directions of flow, constitute the coolant connections. Each pair of inlets and outlets defines a flow path as a result of their respective flow direction and in each case, at least one flow path that traverses the respective cylinder is assigned to each cylinder (15, 15', 15'', 15'''). The flow directions of the inlets and outlets run transversally to the longitudinal direction of the crankshaft, which is defined by the sequential arrangement of the individual cylinders (15, 15', 15'', 15''') one behind the other. An additional group of inlets and outlets (13, 13'; 14, 14') is arranged parallel to the longitudinal direction of the crankshaft. In addition, as the respective inlets and outlets arranged transversally to said crankshaft direction have metering bores, a thermal cylinder equalisation for each operating point can be achieved by supplying coolant to each cylinder, said supply being adjusted by means of the bores.

Description

Device for cooling an internal combustion engine

description

State of the art

The invention relates to a device for cooling an internal combustion engine, preferably a four-cylinder in-line engine, according to the preamble of the main claim.

A generic device is already known from EP 0 038 556. In this case, a cylinder head and a cylinder block accommodated in the internal combustion engine each have a cooling jacket region designed as a cooler pocket, the cooler pockets arranged separately from one another having coolant connections on the upstream and downstream sides for coupling to the cooling circuit, so that the cylinder head and the cylinder block of the internal combustion engine are separate from one another can be supplied with coolant, so that a separate thermal control of the cylinder head and the cylinder block is possible. However, what is unsatisfactory with this prior art is that due to the integral

Cooling of all cylinders A specific operating point-dependent cooling of individual cylinders of the internal combustion engine cannot be carried out. Advantages of the invention

The device according to the invention with the characterizing features of the main claim has the advantage that the geometric arrangement of the inflow and outflow and their flow direction relative to the arrangement of the cylinders of each individual cylinder is in direct flow contact of a flow path assigned to it and thus the number of flow paths the number of cylinders is dependent, so that a targeted and selective cooling of the individual cylinders or combustion chambers depending on the current

Engine operating state is feasible. This makes it possible to set an approximately uniform temperature distribution of the individual cylinders in all operating states, which has a wear-reducing effect with respect to the corresponding components of the internal combustion engine. Due to the resulting low temperature variance, the tendency to knock or the nitrogen oxide emission can be reduced, for example, under full load operation.

Further advantageous developments and refinements of the invention result from the measures listed in the subclaims.

drawing

An embodiment of the invention is explained in more detail in the following description and drawing. The latter shows in FIG. 1 a side view of an internal combustion engine designed in the exemplary embodiment as a four-cylinder in-line engine with coolant connections of the device according to the invention for coupling to a cooling circuit. FIG. 2 shows a sectional illustration of a cylinder block of the internal combustion engine with upstream and downstream coolant connections of the device according to the invention in a plan view along the section line II-II of FIG. 1. 3 shows a schematic view of the device according to the invention with the associated coolant circuit for cooling the internal combustion engine. Description of the embodiment

1 in its entirety designated 10 for cooling an internal combustion engine 1 1 designed in the exemplary embodiment as a four-cylinder in-line engine each has a cooling jacket region 12 ^' , 12 ^" , 12 ^'" for the cylinder head 1 1 ^' , the cylinder block 11 ^" and the

Combustion chamber 1 1 ^'"of the internal combustion engine 1 1. The cooling jacket regions 12 ^' , 12 ^" are arranged separately from one another and have inflow and outflow flows which are assigned to one another in pairs and which are provided in the exemplary embodiment as coolant connections 13, 13 ^' , 14, 14 ^'are formed and the inflow and outflow side

Serve coupling to the cooling circuit. For this purpose, a pair of coolant connections 13, 13 ^' , 14, 14 ^' for the respectively assigned cooling jacket region 12 ^' , 12 ^"are provided both on the cylinder head 1 1 ^' and on the cylinder block 1 1 ^" , these coolant connections in the horizontal longitudinal direction or in the longitudinal direction of the crankshaft Internal combustion engine 1 1, ie in the direction defined by the arrangement of the individual cylinders 15, are arranged on opposite side walls 16, 16 ^' of internal combustion engine 11 such that the respective flow direction of these coolant connections is aligned along the longitudinal direction of the crankshaft. Furthermore, in a direction transverse to the longitudinal direction of the crankshaft, which is also arranged horizontally, both on the cylinder block 1 1 ^" and on the cylinder head 1 1 ^' on opposite side walls 25, 25 ^', a further group of inflows and outflows formed in the exemplary embodiment as coolant connections - gen 17 - 20, 17 ^' - 20 ^' , 21 - 24, 21 ^' - 24 ^' provided.

FIG. 2 illustrates the geometrical arrangement of this second group of coolant connections 17-20 and 17 ^' - 20 ^' on the cylinder block 1 1 ^" , with each cylinder 15, 15 ^' , 15 ^" , 15 ^'" each having two coolant connections 17, 17 ^' , 18 , 18 ^' , 19, 19 ^' , 20, 20 ^'are assigned, the one another diametrically and mirror-symmetrically with respect to the respective cylinder

15, 15 ^' , 15 ^" , 15 ^{'" are} opposite. The individual pairs of coolant connections 17 - 20, 17 ^' - 20 ^' , 21 - 24, 21 ^' - 24 ^' are thus corresponding arranged to the spacing of the respective adjacent cylinder along the crankshaft longitudinal direction spaced from each other, wherein the inflow-side coolant connectors 17 on the front-side side wall 25 of the cylinder block 1 1 - 20 ^'are arranged such that their - 20 and on the opposite side wall ^25', the downstream coolant connections 17 ^' the respective flow direction transverse to the longitudinal direction of the crank and points to the respectively assigned cylinder 15, 15 ^' , 15 ^" , 15 ^'" . In contrast to the longitudinally aligned coolant connections 13, 13 ^' , 14, 14 ^' , through which the cylinders 15, 15 ^' , 15 ^" , 15 ^{'", which} are arranged in series one behind the other, flow against one another, the individual cylinders 15, 15 ^' , 15 ^" , 15 ^'" due to the parallel parallel flow of coolant flows directly and simultaneously. The cylinder head 11 ^{′, which} is not shown separately for reasons of symmetry, is also in an analogous manner with the same geometrical arrangement of inflow and outflow flows 21 - 24 and 21 designed as coolant connections.

24 ^' so that on opposite side walls 25, 25 ^{' of} the cylinder head 1 1 ^' each cylinder 15, 15 ^' , 15 ^" , 15 ^'" each have a pair of coolant connections 21, 21 ^' , 22, 22 ^' , 23, 23 ^' , 24, 24 ^' , the flow direction of which points transversely to the longitudinal direction of the crankshaft and to the respectively assigned cylinder 15, 15 ^' , 15 ^" , 15 ^'" . This the

Cylinder head 1 1 ^'associated group of inflow and Abstromungen 21 - 24, ^21' - 24 ^'feed the for the combustion chamber ^11''provided broken down in the cooling pockets cooling jacket portion ^12'", while in contrast, the cylinder block ^11" associated group of inflow and Outflows 17 - 20, 17 ^' - 20 ^' open into the cooling jacket region 12 ^" accommodated in the cylinder block 11 ^" . Furthermore, the inflow and outflow flows 17 - 20, 17 ^' - 20 ^' , 21 - 24, 21 ^' - 24 ^' each have suitable metering bores with flow directions running transversely to the longitudinal direction of the crankshaft, by means of a coolant supply which can be tuned via the metering bores to each cylinder 15, 15 ^' , 15 ^" , 15 ^'" and which is thereby controllable

Longitudinal and transverse flow through the cylinders ensures thermal cylinder equalization for every operating point. 3 shows the device 10 according to the invention with the associated cooling circuit. On the inflow side, the coolant connections 17 - 20 assigned to the cylinder block 11 "and arranged in the transverse direction are connected to a first outlet of a mixing valve 27, while its second outlet is connected on the inflow side to the longitudinally arranged coolant connection 14, so that this mixing valve 27 adjusts the mixing ratio between serves the coolant connection 14 arranged in the longitudinal direction and the coolant connections 17 - 19 arranged in the transverse direction. In an analogous manner, those on the inflow side which are assigned to the cylinder head 11 ^' and are arranged in the transverse direction

Coolant connections 21-24 are connected to a first outlet of a further mixing valve 27 ', while its second outlet is connected on the inflow side to the longitudinally arranged coolant connection 13, so that this second mixing valve 27 ^' adjusts the mixing ratio between the longitudinally arranged coolant connection 13 and the coolant connections 21 - 24 arranged in the transverse direction. The input of the first mixing valve 27 with a first output of a third mixing valve 28 and the input of the second mixing valve 27 ^' with a second are used to set the upstream coolant mixing ratio between cylinder head 11 ^' and cylinder block 11 ^"

Output of the third mixing valve 28 in connection.

On the outflow side, the transverse coolant connections 17 ^′ - 20 ′ assigned to the cylinder block 11 ^″ are connected to a first inlet of a mixing valve 29, while its second inlet is connected on the outflow side to the coolant connection 14 ^′ arranged in the longitudinal direction cylinder head associated with 11 ^"and in the transverse direction arranged coolant connections 21 ^'- ^24' 'is connected, while the second input of which is arranged in the longitudinal direction of coolant telanschluß ^13' to a first input of a further mixing valve 29 is downstream connected. Both mixing valves 29, 29 ^' can be set separately from one another and serve to return the coolant heated in the internal combustion engine 11; they each have one Output on, the output of the mixing valve 29 being connected to the output of the mixing valve 29 ^' ; These two outputs are connected to an input of a thermostat valve 31 which comprises feeding the output side via the mixing valves 29, 29 ^'of the cylinder head 1 1 "and the cylinder block 1 ^1' flowing heated coolant in a cooler 32nd The radiator 32 performs its part, reduced-temperature coolant to a feed pump 33, which is connected on the output side to an inlet of the mixing valve 28. Via a branching point 34 arranged upstream of the inlet of the thermostatic valve 31, part of the coolant flowing in from the return valves 29, 29 ^'is branched off and one

Heat exchanger 35 is supplied, the outlet side of which is connected via a reducing valve 36 to a branching point 37 interposed between the cooler 32 and the feed pump 33, so that the coolant which is reduced in temperature in the heat exchanger 35 is fed to the feed pump 33. Part of the coolant supplied to the thermostatic valve 31 is supplied to the feed pump via a second outlet of the thermostatic valve 31 coupled to the branching point 37. The branches of the coolant circuit defined in each case by the cooler 32 and the heat exchanger 35 can therefore be operated by a single feed pump 33. Thus, for example, for the inlets and outlets shown in FIG

The following flow conditions can be implemented in the outflow of the cylinder block 11 ^" : In a first embodiment, the partial flows supplied to the four transversely arranged inflow and outflow flows 17-20 and 17 ^' - 20 ^{' of} the cylinder block 1 1 ^" each amount to approximately 25% of the cylinder block 1 1 ^" supplied coolant flow, while the partial flow in the longitudinally arranged inflow 14 of the cylinder block 11 ^{" is} about 0% of the coolant flow supplied to the cylinder block, so that the corresponding partial flow of about 0% flows out at the corresponding outflow 14 ^' . In a second embodiment, the partial flows supplied to the transversely arranged inflows 17-20 of the cylinder block 11 ^" each amount to approximately 0% of the coolant flow supplied to the cylinder block 11 ^" , with the corresponding outflows 17 ^' - 20 ^{' are} also discharged about 0%, while the partial flow in the longitudinally arranged inflow 14 of the cylinder block 1 1 ^"is approximately 100% of the coolant flow supplied to the cylinder block, so that the corresponding partial flow 100 ^' at the corresponding outflow 14 ^' ) In a third embodiment, the partial flows of the coolant flow supplied to the cylinder block 1 1 ^" supplied to the four transversely arranged inflows 17 - 20 of the cylinder block 11" each amount to approximately 10%, with approximately 25% each of the corresponding outflow 17 ^' - 20 ^' are discharged while the partial flow in the longitudinally arranged inflow 14 of the cylinder block 1 1 ^{"is set} at approximately 60%, so that approximately 0% flows off at the corresponding outflow 14 ^' . In a fourth embodiment, the amount the four transverse Zustromungen 17 - 20 of the cylinder block 1 1 ^"supplied to partial streams of ^'the cylinder block ^11" supplied coolant flow in each case approximately 0%, with the corresponding thereto Abstromungen ^17' - 20 ^'are each about 25 % are removed, while the partial flow in the longitudinally arranged inflow 14 of the cylinder block 11 ^{"is set} at approximately 100%, so that approximately 0% flows off at the corresponding outflow 14 ^' . It is therefore characteristic of the invention that a group is used as the coolant connections of inflows 17 - 24 and outflows 17 ^' - 24 ^' which are assigned to one another in pairs and each have flow directions, a pair of inflows and outflows each defining a flow path on the basis of their respective flow direction and each cylinder 15, 15 ^' , 15 ^" , 15 ^'"in each case at least one flow flowing over the respective cylinder path is assigned. Their flow directions run transversely to the longitudinal direction of the crankshaft defined on the basis of the arrangement of the individual cylinders 15, 15 ^' , 15 ^" , 15 ^'" . Another group of inflows and outflows 13, 13 ^' ; 14, 14 ^' is arranged along the longitudinal direction of the crankshaft. In addition, since the inflow and outflow flows arranged transversely thereto each have metering bores, re coolant supply to each cylinder a thermal cylinder equalization can be achieved for each operating point.

Overall, the following advantages can be achieved: The adjustability of an almost uniform temperature distribution in all operating states reduces the thermal load on those belonging to the combustion chamber

Components and thus reduces wear. Due to the selective supply of the partial coolant flows to the individual combustion chamber areas and the precise cooling that is possible as a result, the volume flow required for a uniform temperature distribution drops and thus leads to a reduction in consumption. A lowering of the flow resistance also reduces consumption due to the parallel design of the partial coolant flows.

Claims

claims

1. Device for cooling an internal combustion engine, preferably a four-cylinder in-line engine, with coolant connections provided on the internal combustion engine to a cooling circuit, the

Coolant connections open into at least one cooling jacket area of the internal combustion engine, characterized in that a group of inflows (17 - 24) and outflows (17 '- 24 ^' ) assigned to one another in pairs is provided as the coolant connections, a respective pair of inflows and outflows due to their respective Flow direction defines a flow path and each cylinder (15, 15 ^' , 15 ^" , 15 ^'" ) is assigned at least one flow path flowing over it.

2. Apparatus according to claim 1, characterized in that the respective flow paths flowing the cylinders (15, 15 ^' , 15 ^" , 15 ^'" ) run parallel to one another.

3. Apparatus according to claim 1 or 2, characterized in that the mutually assigned and each having flow directions inflow and outflow (17, 17 ^' - 24, 24 ^' ) are arranged such that the flow directions transverse to due to the sequential arrangement of the individual Cylinder (15, 15 ^' , 15 ^" , 15 ^'" ) defined crankshaft longitudinal direction.

Device according to Claim 3, characterized in that the respective pairs of inflow and outflow flows (17, 17 ^' - 24, 24 ^' ) are spaced apart from one another in accordance with the distance between the respectively adjacent cylinders (15, 15 ', 15 ", 15 ^'" ) are.

Device according to Claims 3 to 4, characterized in that the respective pairs of inflow and outflow flows (17, 17 ^' - 24, 24 ^' ) are diametrically and mirror-symmetrical to one another with respect to the respectively assigned cylinder (15, 15 ^' , 15 ", 15'") face each other.

6. The device according to claim 5, characterized in that the respective pairs of inflow and outflow (17, 17 ^' - 24, 24') on opposite side walls (25, 25 ^' ) of both one of the internal combustion engine (11) cylinder head ( 11 ^' ) as well as a cylinder block encompassed by the internal combustion engine (11)

(11 ^" ) are arranged.

7. The device according to claim 6, characterized in that the pairs of inflow and outflow flows (21, 21 ^' - 24, 24 ^' ) assigned to the cylinder head (11 ^' ) to a cooling jacket region (12 ^' ) accommodated in the cylinder head (11 ^' ) ^' ) are connected.

8. The device according to claim 7, characterized in that the pairs of inflow and outflow flows (21, 21 ^' - 24, 24 ^' ) assigned to the cylinder head (11 ^' ) are provided for a combustion chamber (11) encompassed by the internal combustion engine (11). 11 ^'" ) provided cooling jacket area provided as cooling pockets (12 ^'" ).

9. Device according to one of claims 6 to 8, characterized in that the pairs of inflow and outflow flows (17 - 20, 17 ^' - 20') assigned to the cylinder block (11 ^" ) to one in the cylinder derblock (1 1 ") recorded cooling jacket area (12 ^" ) are connected.

10. Device according to one of claims 1 to 9, characterized in that the inflow and outflow (17 - 24, 17 ^' - 24 ^' ) have metering bores.

11. The device according to one of claims 1 to 10, characterized in that a further group of inflow and outflow (13, 13 ^' ; 14, 14') is provided on opposite side walls (16, 16 ^' ) penetrated by the longitudinal direction of the crankshaft, the flow directions of which are aligned along the longitudinal direction of the crankshaft.

12. The apparatus according to claim 11, characterized in that the

Device (10) has valve means (27, 27 ^' , 28, 29, 29', 31, 36) with which the inflow and outflow (13, 13 ^' , 14, 14 ^' ; 17 - 20, 17 ^' - 20 ^' ; 21 - 24, 21 ^' - 24 ') can be controlled such that a larger part of the coolant flow supplied by the cooling circuit (32, 33, 34, 35, 36, 37) via the group of inflows and outflows arranged transversely to the longitudinal direction of the crankshaft (17 - 20, 17 ^' - 20 ^' , 21 - 24, 21 ^' - 24 ^' ) flows and a smaller part of the coolant flow on the other hand via the group of inflow and outflow flows (13, 13 ^' , 14, 14 ^' ) flows.

13. The apparatus according to claim 12, characterized in that the valve means have at least a first mixing valve (28) for dividing the coolant flow in the cylinder block (1 1 ^" ) and the cylinder head (1 1 ^' ) each assigned partial flows.

14. The apparatus according to claim 13, characterized in that the valve means a first group of at least two mixing valves (27, 27 ^' ) arranged downstream of the first mixing valve (28) for setting a mixture of the longitudinally arranged inflow and outflow flows ( 13, 14) and, on the other hand, have partial flows of the coolant flow associated with the transversely arranged inflow and outflow flows (17-20, 21-24).

15. Device according to one of claims 13 or 14, characterized in that the valve means have a second group of at least two further mixing valves (29, 29 ^' ) for returning coolant flowing out of the internal combustion engine (11).

16. The apparatus of claim 14 or 15, characterized in that the mixing valves included in the respective group (27, 27 ^' ; 29, 29 ^' ) are arranged in parallel with each other.

17. Device according to one of claims 13 to 16, character- ized in that the valve means are designed such that - the cylinder block (1 1 ^" ) associated mixing valves (27, 28) can be switched off at least temporarily.

18. Device according to one of claims 12 to 17, characterized in that the transversely arranged inflow and outflow

(17 - 24, 17 ^' - 24 ^' ) assigned partial flows of the coolant flow are selectively adjustable relative to each other.

19. Device according to one of claims 12 to 18, characterized in that the valve means are switched such that the

Partial flows in the transversely arranged inflow and outflow (17 - 20, 17 '- 20 ^' ) of the cylinder block (1 1 ^" ) each about 0% of that Cylinder block (11 ") supplied coolant flow and in the longitudinally arranged inflow and outflow (14, 14 ') of the cylinder block (1 1 ^" ) amount to about 100% of the coolant flow supplied to the cylinder block.

20. Device according to one of claims 12 to 18, characterized in that the valve means are switched such that the partial flows in the transversely arranged inflow and outflow (17 - 20, 17 ^' - 20 ^' ) of the cylinder block (11 ^" ) each amount to approximately 25% of the coolant flow supplied to the cylinder block (11 ") and amount to approximately 0% of the coolant flow supplied to the cylinder block in the longitudinally arranged inflow and outflow flows (14, 14 ^' ) of the cylinder block (11 ^" ).

21. The apparatus according to claim 18, characterized in that the

Valve means are switched in such a way that the partial flows in the transversely arranged inflow and outflow (17 - 20, 17 ^' - 20 ^' ) of the cylinder block (1 1 ^" ) each about 10% in the inflows and each about 25%) in the outflows ( 17 ^' - 20 ^' ) of the coolant flow supplied to the cylinder block (11 ^" ), while in contrast in the longitudinally arranged inflow and outflow flows (14, 14 ^' ) of the cylinder block (11 ^" ) about 60% in the inflow (14) and amount to approximately 0% in the outflow (14 ^' ) of the coolant flow supplied to the cylinder block.

22. The apparatus according to claim 18, characterized in that the

Valve means are switched in such a way that the partial flows in the transversely arranged inflow and outflow (17 - 20, 17 ^' - 20 ^' ) of the cylinder block (1 1 ^" ) each have about 0% in the inflows and each about 25% in outflows (17th ^' - 20 ^' ) of the coolant flow supplied to the cylinder block (11 ^" ), while on the other hand they flow in the longitudinally arranged inflow and outflow flows (14, 14 ^' ) of the cylinder Linderblocks (11 ") about 100% in the inflow (14) and about 0% in the outflow (14 ') of the coolant flow supplied to the cylinder block.