DE102017218834B4 - Coolant channel arrangement for an internal combustion engine - Google Patents

Abstract

An internal combustion engine (10) has at least one cylinder head (12), a crankcase (14), at least one in the cylinder head (12) extending first coolant channel (18) and at least one at least partially through the crankcase (14) extending second coolant channel (20). The second coolant channel (20) branches off from the first coolant channel (18) at a branch (22) which lies inside the cylinder head (12).

Description

The invention relates to an internal combustion engine with a cylinder head and a crankcase.

Internal combustion engines must always be tempered, in particular in order to dissipate the heat generated during the combustion process. The cylinder head is the more critical component of an internal combustion engine, so the cylinder head must be cooled more than the crankcase. At the same time warming of the crankcase is desirable in a cold start of the engine to bring the crankcase quickly to its operating temperature. The cylinder head and the crankcase therefore have different requirements for the temperature.

Usually, the temperature of an internal combustion engine is achieved by means of coolant channels of a coolant circuit which extend through the cylinder head and the crankcase. Through the coolant channels flows a coolant, which causes a temperature of the cylinder head or the crankcase. In order to meet the different requirements of cylinder head and crankcase, so-called split-cooling concepts are known in which the cylinder head and the crankcase have separate cooling circuits, which are controlled differently.

An internal combustion engine with a split-cooling concept is for example from the DE 20 2017 102 039 U1 known.

The DE 102 12 672 A1 shows a liquid-cooled internal combustion engine, in which a coolant circuit is provided, which extends through both the cylinder head and through the crankcase.

Out DE 100 48 582 A1 a liquid-cooled cylinder head for an internal combustion engine is known in which in the cylinder head housing for each combustion chamber, a coolant space is designed, which at least partially surrounds the inlet and outlet ports and the receiving shaft for a spark plug or an injection valve.

In the DE 102 44 829 A1 Further, there is shown a liquid-cooled internal combustion engine having at least two cylinders arranged in series. The waste heat transfer from a combustion chamber near wall region of a cylinder head takes place here using a liquid cooling medium.

The problem with such split-cooling concepts is that shut-off systems, such as switched valves, are necessary to direct the flow of coolant. However, these valves are a cost factor, increase the back pressure in the coolant channel and have a certain susceptibility to interference.

It is therefore an object of the invention to provide an internal combustion engine with a cylinder head and a crankcase, which meets the different requirements of the temperature of the cylinder head and the crankcase and at the same time is efficient and reliable.

The object is achieved by an internal combustion engine with a cylinder head, a crankcase with at least one cylinder, at least one extending in the cylinder head first coolant channel and at least one at least partially extending through the crankcase second coolant channel, wherein the second coolant channel branches off from the first coolant channel at a branch, the lies within the cylinder head. The first coolant channel has a first portion extending from the coolant inlet to the branch, and the first coolant channel has a second portion which extends from the branch to the coolant outlet of the cylinder head. The second section is in this case arranged largely on the longitudinal axis of the cylinder-facing side of the first section.

In this way it is achieved that the majority of the heat of the cylinder head is discharged through the coolant flowing through the second portion, since the cylinder head is warmer to the longitudinal axis than radially away from the longitudinal axis.

In particular, no valves or other shut-off systems are provided at the branch. In this way, the coolant flowing through the cylinder head is also used to control the temperature of the crankcase, whereby on the one hand the cylinder head can be cooled and at the same time the crankcase can be tempered. By a suitable choice of the geometry and / or the position of the branch, the temperature of the coolant flowing to the crankcase can be adjusted.

Thus, no valves or other shut-off systems are necessary to meet the different temperature requirements of the cylinder head and the crankcase.

For example, in a multi-cylinder engine, the second coolant passage extends through the lands between two cylinders.

For example, the cylinder head has at least one coolant inlet for introducing coolant into the assembly of cylinder head and crankcase and at least one coolant outlet for removing coolant from the assembly of cylinder head and crankcase, wherein the first coolant channel extends from the coolant inlet to the coolant outlet, whereby the cylinder head can be efficiently cooled.

It is also conceivable that the second coolant channel extends from the branch through the crankcase to the coolant outlet of the cylinder head. In this case, the crankcase requires neither a coolant inlet nor a coolant outlet. In the context of this invention, the terms coolant outlet and coolant inlet do not denote the openings of the second coolant channel between the cylinder head and the crankcase, but only those openings of the coolant channels through which coolant can flow into or out of the cylinder head and crankcase assembly.

In one embodiment of the invention, the crankcase has a coolant outlet for the removal of coolant from the assembly of cylinder head and crankcase, wherein the second coolant channel extends from the branch to the coolant outlet of the crankcase, whereby the crankcase can be tempered in a simple manner. The crankcase has no coolant inlet through the coolant from other components than the cylinder head is introduced into the crankcase.

For example, the coolant outlets of the cylinder head and the crankcase are arranged on the same side of the cylinder, in particular one above the other.

Preferably, the coolant inlet and the coolant outlet of the cylinder head lie in a view in the direction of the longitudinal axis of the cylinder on the same side of the cylinder, in particular side by side, and the branch is on the other side of the cylinder, and / or the branch is the coolant inlet or the coolant outlet the cylinder head substantially diametrically opposite. This ensures that the coolant must flow through the cylinder head before it partially flows to the junction to the crankcase, whereby the waste heat of the cylinder head can be used efficiently for controlling the temperature of the crankcase.

In one embodiment of the invention, the branch is arranged on the side of the cylinder on which an inlet valve for introducing fuel into the cylinder is located, whereby a simple venting is made possible, in particular in the case of V-engines. This is achieved by the coolant flow going in the same direction as air bubbles in the coolant would rise.

Preferably, the second section is arranged completely on the side of the first section facing the longitudinal axis of the cylinder.

In one embodiment of the invention, the geometries and / or positions of the first coolant channel, in particular the first section and the second section, the second coolant channel and / or the branch are selected such that less than 15%, in particular less than 10%, particularly preferred about 8% of the incoming coolant at the junction flow into the second coolant channel. In this way, without the use of valves, a certain proportionality of the cooling between the cylinder head and the crankcase is achieved.

In one embodiment of the invention, the cylinder head has two coolant inlets and the first coolant channel has two first sections which are each associated with one of the coolant inlets and which connect the respective coolant inlet to the branch. In this way, a symmetrical structure of the first coolant channel can be achieved in the cylinder head, whereby a homogeneous heat dissipation is ensured. In this case, the coolant outlet can be arranged between the coolant inlets.

It is also conceivable that either a second section or two second sections of the first coolant channel are provided. The one or the two second sections may be arranged between the two first sections, in particular radially between the two first sections.

In one embodiment, the internal combustion engine may comprise a plurality of cylinders each having a first coolant channel and a second coolant channel, whereby a multi-cylinder engine can be tempered in a simple manner.

• - 1 eine schematische Schnittansicht einer ersten Ausführungsform eines erfindungsgemäßen Verbrennungsmotors,
• - 2 eine schematische Schnittansicht durch den Zylinderkopf des Verbrennungsmotors nach 1,
• - 3 eine schematische Schnittansicht durch das Kurbelgehäuse des Verbrennungsmotors nach 1,
• - 4 eine zweite Ausführungsform eines erfindungsgemäßen Verbrennungsmotors in einer schematischen Seitenansicht,
• - 5 eine schematische Schnittansicht durch den Zylinderkopf des Verbrennungsmotors nach 4, und
• - 6 eine schematische Schnittansicht durch das Kurbelgehäuse des Verbrennungsmotors nach 4.

Further features and advantages of the invention will become apparent from the following description and from the accompanying drawings, to which reference is made. In the drawings show:

• - 1 a schematic sectional view of a first embodiment of an internal combustion engine according to the invention,
• - 2 a schematic sectional view through the cylinder head of the engine according to 1 .
• - 3 a schematic sectional view through the crankcase of the internal combustion engine according to 1 .
• - 4 A second embodiment of an internal combustion engine according to the invention in a schematic side view,
• - 5 a schematic sectional view through the cylinder head of the engine according to 4 , and
• - 6 a schematic sectional view through the crankcase of the internal combustion engine according to 4 ,

In the 1 to 3 is a first embodiment of an internal combustion engine 10 with a cylinder head 12 and a crankcase 14 partially shown.

The internal combustion engine 10 is for example a V-engine with two cylinder banks, each with four cylinders 16 , For the sake of clarity, only one of the cylinder banks is shown in the figures, wherein in 1 the second cylinder bank is indicated by dashed lines.

The cylinders 16 are for example in the intended installation position of the internal combustion engine 10 tilted in a vehicle, ie the longitudinal axis L of the cylinder 16 includes with the vertical or the direction G of gravity a non-zero angle.

The internal combustion engine 10 has a first coolant channel 18 and a second coolant channel 20 at a fork 22 in the cylinder head 12 fluidly connected to each other. The two coolant channels 18 . 20 are part of a cooling circuit for temperature control of the internal combustion engine 10 ,

The two coolant channels 18 . 20 are for every cylinder 16 identical, so in the following the coolant channels 18 . 20 only one cylinder 16 described by way of example.

The internal combustion engine 10 also has a service section 24 on, in which two feed channels 26 ( 2 ) and a discharge channel 28 are provided.

In the embodiment according to the 1 to 3 consists of the supply section 24 made of two parts, each one-piece with the cylinder head 12 or the crankcase 14 are formed. In the context of this invention, the supply section 24 but not as part of the cylinder head 12 or the crankcase 14 be considered.

The cylinder head 12 has two coolant inlets 30 ( 2 ) and a coolant outlet 32 on, in which the feed channels 26 or the discharge channel 28 of the service section 24 lead.

Through the coolant inlets 30 and the coolant outlet 32 thus becomes coolant of the cylinder head assembly 12 and crankcase 14 supplied or removed from this.

In 2 It is good to see that the coolant outlet 32 between the two coolant inlets 30 lies, each on one side of the cylinder 16 are arranged.

Regarding the cylinder 16 diametrically to the coolant outlet 32 opposite is the turnoff 22 thus on the other side of the cylinder 16 is arranged.

The two sides of the cylinder 16 for example, from the midline M ( 2 ) of the cylinder bank, for example defined by a degree through the centers of the adjacent cylinders 16 to be separated.

The turnoff 22 is on the side of the cylinder 16 provided, at which the inlet valve 34 (in 1 merely indicated) for introducing the fuel into the cylinder 16 located.

As in 2 The first coolant channel begins 18 at the coolant inlets 30 , the turnoff happens 22 and runs through the cylinder head 12 to the coolant outlet 32 ,

The first coolant channel 18 is completely in the cylinder head in the embodiment shown 12 provided and has two first sections 36 and a second section 38 on.

The first two sections 36 run between each one of the coolant inlets 30 and the turnoff 22 , and the second section 38 runs from the junction 22 to the coolant outlet 32 ,

The second section 38 runs between the first two sections 36 and happens the longitudinal axis L of the cylinder 16 ,

The second section 38 thus runs completely on the side of the first sections 36 , each of the longitudinal axis L of the cylinder 16 is facing.

At the junction 22 begins the second coolant channel 20 and runs in the direction of the crankcase 14 ,

The geometries, in particular the flow diameter, and / or the layers of the branch 22 and / or the coolant channels 18 . 20 , in particular the first section 36 and the second section 38 , influence the volume or mass flow of the coolant at the point of diversion 22 ,

By a suitable selection of the geometry and / or the layers can be determined which Share of at the turnoff 22 incoming coolant into the second coolant channel 20 flows and what proportion in the first coolant channel 18 remains and through the second section 38 running.

In the drawings, the layers and geometries are not drawn to scale for purposes of illustration. Preferably, they are chosen such that less than 15%, in particular less than 10%, particularly preferably about 8%, of the branching 22 incoming coolant into the second coolant channel 20 arrives.

The second coolant channel 20 first passes through the cylinder head 12 and then into the crankcase 14 ,

In the embodiment according to the 1 to 3 also has the crankcase 14 a separate coolant outlet 40 on, in the discharge channel 28 of the service section 24 empties.

The coolant outlet 40 of the crankcase 14 is on the same page as the coolant outlet 32 of the cylinder head 12 intended. For example, the coolant outlet 40 of the crankcase 14 and the coolant outlet 32 of the cylinder head 12 longitudinal L of the cylinder 16 arranged one above the other.

The second coolant channel 20 runs from the junction 22 to the coolant outlet 40 of the crankcase 14 ,

The crankcase 14 thus has no separate coolant inlet, through the coolant in the assembly of cylinder head 12 and crankcase 14 can be introduced.

Longitudinal L of the cylinder 16 runs the second coolant channel 20 , as in 1 can be seen, first from the cylinder head 12 away and branches into two branches 42 ,

The branches 42 each move further away from the cylinder head 12 until they turn from a turning point 44 back to the cylinder head 12 go-out.

Due to the tilting of the longitudinal axis L of the cylinder 16 opposite the vertical, the branches run 42 and thus the second coolant channel 20 downstream of the turning point 44 close to the vertical. The coolant therefore flows from the inflection point 44 essentially in the opposite direction G of gravity.

In this way, air bubbles rise in the branches 42 form, in the flow direction, whereby the venting of the second coolant channel 20 is simplified.

In addition, each of the two branches 42 two different arms 46 have on different sides around the cylinder 16 walk around. For example, at least one of the arms extends 46 through one of the bridges 48 of the crankcase 14 between two adjacent cylinders 16 are formed.

As a result, the second coolant channel is divided 20 in four subchannels. Conceivable, of course, any other number of subchannels or a second coolant channel 20 that does not branch.

In operation of the internal combustion engine 10 Coolant flows through the feed channel 26 of the supply section 24 through the two coolant inlets 30 in the cylinder head 12 , There it first flows through the first sections 36 in the direction of the junction 22 , The flow of the coolant is shown by arrows in the figures.

By doing that, the first sections 36 on the edge of the cylinder 16 This will happen in the first sections 36 flowing coolant heats slightly. This is because on the edge of the cylinder 16 lower temperatures occur than in the middle of the cylinder 16 ,

At the junction 22 Now, a small part, in about 8%, of the slightly heated coolant into the second coolant channel 20 guided and the remaining coolant continues to flow through the first coolant channel 18 , more precisely through the second section 38 ,

The coolant passing through the second section 38 flows, then flows exactly over the cylinder 16 along and is strongly heated, that is, it transports a lot of heat from the cylinder head 12 from. Preferably, most of the heat is removed by the portion of the coolant passing through the second section 38 flows.

In contrast, the coolant flowing at the branch flows 22 in the second coolant channel 20 was steered, through the crankcase 14 , In particular, shortly after the start of the internal combustion engine 10 is the crankcase 14 still very cold, so that the slightly preheated coolant the crankcase 14 warms up.

In the course of operation of the internal combustion engine 10 Imagine a balance in the crankcase 14 in which also the coolant flowing through the second coolant channel 20 flows, heat of the crankcase 14 removed.

In this way can be valveless and without further shut-off a coolant circuit of an internal combustion engine 10 Realize that on the different requirements of the cylinder head 12 and the crankcase 14 Consideration.

In the 4 to 6 a second embodiment of the invention will be described, which is substantially the first embodiment of 1 to 3 equivalent. In the following, therefore, only the differences are discussed, wherein identical and functionally identical parts are provided with the same reference numerals.

In the second embodiment, the service section is 24 not integral with the cylinder head 12 and the crankcase 14 trained, but a separate component, for example, from hoses.

In addition, the second coolant channel runs 20 , as in 4 to see again back in the cylinder head 12 after he has the cylinders 16 happened.

The second coolant channel 20 thus runs in the second embodiment of the branch 22 in the cylinder head 12 through the crankcase 14 and on the other side of the cylinder 16 More specifically, on the side of the coolant outlet 32 , back in the cylinder head 12 ,

There, the second coolant channel opens 20 at an estuary 50 in the first coolant channel 18 and the coolant of the second coolant channel 20 then flows through the coolant outlet 32 of the cylinder head 12 ,

Thus, the crankcase has 14 in the second embodiment, neither a coolant inlet nor a coolant outlet.

Also the second section 38 of the first coolant channel 18 is performed differently from the first embodiment in the second embodiment.

In the second embodiment, there are two second sections 38 provided or the second section 38 has two branches separated from each other by the branch 22 to the coolant outlet 32 run. It is conceivable that none of the second sections 38 the longitudinal axis L cuts, but that the second sections 38 on separate sides on the longitudinal axis L run over.

Of course, the various features of the embodiments can be combined with each other as desired.

It is also conceivable that more than one turn 22 is provided. Likewise, more than one coolant outlet can also be used 32 in the cylinder head 12 be provided.

Claims (9)

Internal combustion engine having a cylinder head (12), a crankcase (14) with at least one cylinder (16), at least one first coolant channel (18) extending in the cylinder head (12) and at least one second coolant channel (20) extending at least partially through the crankcase (14) ), wherein the second coolant channel (20) branches off from the first coolant channel (18) at a branch (22) located inside the cylinder head (12), the first coolant channel (18) having a first section (36) extending from the first coolant channel (18) Coolant inlet (30) to the branch (22) extends, and a second portion (38) extending from the branch (22) to the coolant outlet (32) of the cylinder head (12), characterized in that the second portion (38) is arranged largely on the longitudinal axis (L) of the cylinder (16) facing side of the first portion (36). Internal combustion engine Claim 1 characterized in that the cylinder head (12) comprises at least one coolant inlet (30) for introducing coolant into the cylinder head (12) and crankcase assembly (14) and at least one coolant outlet (32) for removing coolant from the cylinder head assembly (12). 12) and crankcase (14), wherein the first coolant channel (18) extends from the coolant inlet (30) to the coolant outlet (32). Internal combustion engine Claim 1 or 2 characterized in that the crankcase (14) includes a coolant outlet (40) for removing coolant from the cylinder head (12) and crankcase assembly (14), the second coolant passage (20) extending from the branch (22) to the coolant outlet (40) of the crankcase (14). Internal combustion engine Claim 2 or 3 , characterized in that in a view in the direction of the longitudinal axis (L) of the cylinder (16) of the coolant inlet (30) and the coolant outlet (32) of the cylinder head (12) on the same side of the cylinder (16), in particular adjacent to each other and the branch (22) lies on the other side of the cylinder (16) and / or the branch (22) lies substantially diametrically opposite the coolant inlet (30) or the coolant outlet (32) of the cylinder head (12). Internal combustion engine according to one of the preceding claims, characterized in that the branch (22) on the side of the cylinder (16) is arranged, on which an inlet valve (34) for Introducing fuel into the cylinder (16) is located. Internal combustion engine according to one of the preceding claims, characterized in that the second section (38) is arranged completely on the side of the first section (36) facing the longitudinal axis (L) of the cylinder (16). Internal combustion engine according to one of the preceding claims, characterized in that the geometries and / or positions of the first coolant channel (18), in particular of the first portion (36) and the second portion (38), the second coolant channel (20) and / or the branch (22) is selected such that less than 15%, in particular less than 10%, particularly preferably about 8% of the coolant arriving at the branch (22) flow into the second coolant channel (20). Internal combustion engine according to one of the preceding claims, characterized in that the cylinder head (12) has two coolant inlets (30) and the first coolant channel (18) has two first sections (36) each associated with one of the coolant inlets (30) and the respective coolant inlet (30) connect to the branch (22). Internal combustion engine according to one of the preceding claims, characterized in that the internal combustion engine (10) has a plurality of cylinders (16) each having a first coolant channel (18) and a second coolant channel (20).

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