Internal combustion engine with a heat exchanger arranged in the water jacket of the internal combustion engine

Abstract

Internal combustion engine comprising: a base engine; a water jacket (3) which is formed in the base engine and through which a cooling fluid can flow; a recess (7) in a wall (4) of the base engine which extends into the water jacket (3); a heat exchanger (11) which is arranged at least in sections in the recess (7) and through which a second fluid can flow, so that thermal energy can be exchanged between the cooling fluid and the second fluid; a heat exchanger cover (17) via which the heat exchanger (11) is connected to a fluid circuit through which the second fluid can flow, wherein the heat exchanger (11) is fastened to the heat exchanger cover (17) and the heat exchanger cover (17) is fastened to the base engine; and a pin (25) which positions the heat exchanger cover (17), the support section and the base engine relative to one another.

Description

[0001] The present invention relates to an internal combustion engine having a heat exchanger arranged in a water jacket.

[0002] Heat exchangers are used in internal combustion engines to transfer thermal energy from one fluid circuit to another. For this purpose, internal combustion engines have a cast-in water jacket, for example, in the crankcase and / or cylinder head, in which coolant circulates to cool the internal combustion engine. The heat exchanger can be installed in this water jacket and connected to another fluid circuit, such as the oil circuit.

[0003] DE 10 2019 006 664 A1 discloses an internal combustion engine with a heat exchanger. The heat exchanger is arranged in a pocket of a crankcase, which is part of the water jacket of the internal combustion engine. Within the pocket, the crankcase has an oil inlet and an oil outlet, into which complementary nozzles of the heat exchanger are inserted to connect it to the oil circuit. The heat exchanger is screwed onto the oil inlet and the oil outlet using screw plates. The pocket in the crankcase is closed off by a heat exchanger cover, which includes guide fins. The guide fins surround the heat exchanger, together with cast fins formed in the pocket, so that a small gap is formed between the heat exchanger on one side and the crankcase and heat exchanger cover on the other side, in order to reduce the amount of fluid flowing past the heat exchanger.

[0004] DE 43 13 506 A1 discloses an oil cooler in a disc design with a permeable disc pack provided with an inlet and an outlet. The oil cooler is arranged in a recess of a housing, allowing fluid to flow through it in the longitudinal direction of the disc pack. Sealing strips are arranged transversely to the longitudinal direction of the housing between the sides of the disc pack and the opposite walls of the housing. The oil cooler has a cover that is screwed directly onto an outer surface of the housing.

[0005] Further heat exchangers arranged within a water jacket of an internal combustion engine are shown in the documents DE 10 2005 051 309 A1, DE 10 2013 225 181 A1, DE 10 2015 200 657 A1, DE 10 2018 216 675 A1 and US 2017 / 204812 A1.

[0006] The present invention is based on the object of providing an internal combustion engine with a heat exchanger which enables simple assembly of the heat exchanger in a housing of the internal combustion engine while at the same time maintaining a high positional tolerance.

[0007] To achieve this object, an internal combustion engine is proposed, comprising: a base engine; a water jacket which is formed in the base engine and through which a cooling fluid can flow, a recess in a wall of the base engine which extends into the water jacket, a heat exchanger which is arranged at least in sections in the recess and through which a second fluid can flow, so that thermal energy can be exchanged between the cooling fluid and the second fluid, a heat exchanger cover via which the heat exchanger is connected to a fluid circuit through which the second fluid can flow, wherein the heat exchanger is fastened to the heat exchanger cover and the heat exchanger cover is fastened to the base engine, and a pin which positions the three elements heat exchanger cover, support section and base engine relative to one another.

[0008] In one possible embodiment of the internal combustion engine, the heat exchanger cover can have a support surface. The heat exchanger can have a support section that rests on the support surface of the heat exchanger cover. The support section of the heat exchanger and the base engine can be arranged at a distance from one another. In this case, a gap is formed between the support section of the heat exchanger and the base engine. In other words, the support section of the heat exchanger and the base engine are arranged without contact with one another.

[0009] In a possible further embodiment, the base motor can have a receiving surface. The receiving surface can be flat and / or enclose the recess in the wall of the base motor. The heat exchanger cover can have a sealing portion, wherein the sealing portion of the heat exchanger cover rests on the receiving surface of the base motor. A contact area between the sealing portion and the receiving surface can enclose the recess in the wall of the base motor.

[0010] The sealing portion of the heat exchanger cover can comprise a sealing element that engages the receiving surface of the base engine in the contact area, so that the recess in the wall of the base engine is enclosed by the sealing element. In other words, the recess in the wall of the base engine is sealed from the environment of the internal combustion engine by means of the sealing element.

[0011] In a possible further embodiment, a positioning recess can be provided in each of the base motor, the support section of the heat exchanger, and the heat exchanger cover. The pin can be arranged in the three positioning recesses or extend through them. In particular, the pin can be arranged without play in one, two, or three of the three aforementioned positioning recesses. The positioning recesses can have different diameters. At least two of the three positioning recesses can have different diameters. The positioning recesses of the base motor, the heat exchanger, and the heat exchanger cover can be arranged coaxially on the base motor when the heat exchanger and heat exchanger cover are assembled.

[0012] In another possible embodiment, the pin can be permanently connected to at least one of the base motor, the heat exchanger, and the heat exchanger cover, for example, by gluing, welding, or soldering. In other words, the pin can be connected to at least one of the base motor, the heat exchanger, and the heat exchanger cover in a force-fitting, form-fitting, or material-fitting manner.

[0013] In a further possible embodiment, the pin can be designed in the form of a cylindrical pin, a conical pin, a grooved pin, a clamping pin or a clamping bush.

[0014] In another possible embodiment, the pin can be designed as a dowel pin.

[0015] In another possible embodiment, the heat exchanger and the heat exchanger cover can be clamped together by a screw. The screw can extend through an opening in the heat exchanger into a mating thread in the heat exchanger cover. The screw can be arranged in the opening of the heat exchanger with radial play relative to a longitudinal axis of the pin. In other words, the screw can be preloaded without transverse forces and / or can be arranged within the opening of the heat exchanger without contact with the heat exchanger.

[0016] In another possible embodiment, the heat exchanger cover and the base engine can be clamped together by a screw. The screw can extend through an opening in the heat exchanger cover into a mating thread in the base engine. The screw can be arranged in the opening of the heat exchanger cover with radial play relative to a longitudinal axis of the pin. In other words, the screw can be preloaded without transverse forces and / or can be arranged within the opening of the heat exchanger cover without contact with the heat exchanger cover.

[0017] In a further possible embodiment, the heat exchanger cover can be designed as a cast part, in particular as a die-cast part.

[0018] An embodiment of the internal combustion engine according to the invention is explained below with reference to the drawings. Herein: Fig. 1 is a partial side view of a crankcase of an internal combustion engine according to the invention; Fig. 2 a sectional view of the internal combustion engine from Fig. 1 in section plane II-II ; Fig. 3 a sectional view of the internal combustion engine from Fig. 1 in section plane III-III; and Fig. 4 a sectional view of the internal combustion engine in the section plane IV-IV in Fig. 2.

[0019] The Fig.1 to 4, which are described together below, show parts of an internal combustion engine 1 according to the invention. For the sake of clarity, only the crankcase 2, the heat exchanger 11, the heat exchanger cover 17, and the elements used to connect the aforementioned components are shown in the figures. The internal combustion engine 1 comprises, in particular, a cylinder head (not shown), which is connected to the crankcase 2 in a known manner. The cylinder head and the crankcase 2 can also be referred to together as the basic engine.

[0020] A water jacket 3 is formed in the cylinder head and crankcase 2. A water jacket is a cavity through which cooling fluid can flow to cool the internal combustion engine 1. It will be understood by those skilled in the art that the choice of cooling fluid is not limited to water. Therefore, the water jacket can also be referred to as a cooling fluid jacket.

[0021] The crankcase 2 has a side wall 4 in which a recess 7 is formed, extending into the water jacket 3. The area in which the water jacket 3 is open to the surroundings of the crankcase 2 via the recess 7 can also be referred to as a pocket. The pocket is supplied with cooling fluid through an inlet 8. The cooling fluid can flow out of the pocket again via an outlet 9.

[0022] A heat exchanger 11 is arranged in the recess 7 or in the pocket of the water jacket 3. Two guide ribs 10 are formed in the recess 7. The guide ribs 10 surround the heat exchanger 11 in the region of the recess 7, so that only a small gap is formed between the heat exchanger 11 and the crankcase 2. Thus, only a small portion of the cooling fluid flowing from the inlet 8 via the recess 7 towards the outlet 9 can flow past the heat exchanger 11, thus increasing the effectiveness of the heat exchanger 11. In order to keep the gap around the heat exchanger 11 constant and to achieve the greatest possible effectiveness of the heat exchanger 11, the heat exchanger 11 must be arranged in the recess 7 with small tolerances.

[0023] The heat exchanger 11 is detachably connected to a heat exchanger cover 17. A support section 12 of the heat exchanger 11 rests on a support surface 20 of the heat exchanger cover 17. For this purpose, one or more screws 16 extend through the support section 12 into a mating thread of the heat exchanger cover 17. The support section 12 of the heat exchanger 11 comprises one or more openings through which a screw 16 extends. In the present case, four screws 16 are provided, which extend through four openings in the support section 12. In the region of the openings, the screws 16 are each arranged so as not to make contact with the heat exchanger cover 17. In other words, the screws 16 are arranged in the opening with radial play relative to the longitudinal axis of the screws.

[0024] Due to the clamping force of the screws 16, the support section 12 of the heat exchanger 11 is pressed onto the support surface 20 of the heat exchanger cover 17 or clamped thereto.

[0025] For the exact positioning of heat exchanger 11 and heat exchanger cover 17 relative to one another, the two parts are additionally positioned relative to one another via a first pin 25. In the present case, a second pin 25 is also provided. In this case, the pin 25 is designed as a dowel pin, which is arranged in a bore 21 of the heat exchanger cover 17. The pin 25 also extends without play through an opening 13 in the support section 12 of the heat exchanger 11. The pin 25 projects into a bore 6 of the crankcase 2 on the side of the support section 12 facing away from the heat exchanger cover 17. The pin 25 is thus also arranged without play in the bore 6. The three parts, crankcase 2, heat exchanger 11, and heat exchanger cover 17, are thus arranged with small tolerances relative to one another. This also minimizes the deviations in the gap around the heat exchanger 11 in the water jacket and the associated leakage losses.

[0026] The pin 25 can be permanently connected to at least one of the crankcase 2, the support section 12 of the heat exchanger 11, and the heat exchanger cover 17, for example by gluing, welding, or soldering. In other words, the pin 25 can be connected to at least one of the crankcase 2, the support section 12 of the heat exchanger 11, and the heat exchanger cover 17 in a force-fitting, form-fitting, or material-fitting manner.

[0027] The heat exchanger cover 17 comprises an annular or circumferential sealing section 22, which is in contact with a receiving surface 5 of the crankcase 2. The bore 6 extends from this receiving surface 5 into the crankcase 2. The receiving surface 5 surrounds or encloses the recess 7. One or more screws 24 extend through a bore 21 of the heat exchanger cover 17 into a mating thread in the crankcase 2. The clamping force of the screws 24 clamps or presses the sealing section 22 of the heat exchanger cover 17 against the receiving surface 5 of the crankcase 2.

[0028] Furthermore, a circumferential sealing recess 23 is provided in the heat exchanger cover 17, which surrounds the recess 7. A sealing element 26 is inserted into the sealing recess 23 and is clamped between the heat exchanger cover 17 and the receiving surface 5 of the crankcase 2. The sealing element 26 seals the pocket from the surroundings of the crankcase 2.

[0029] The support section 12 of the heat exchanger 11 is arranged without contact with the crankcase 2. A circumferential gap 27 is formed between the support section 12 of the heat exchanger 11 and the crankcase 2.

[0030] In the present case, the heat exchanger 11 is designed as an oil cooler, which is connected to the oil circuit of the internal combustion engine 1 via an inlet connection 14 and an outlet connection 15. For this purpose, the inlet connection 14 projects into an inlet opening of the heat exchanger cover 17, which is concealed in the figures, and the outlet connection 15 projects into an outlet opening of the heat exchanger cover 17, which is concealed in the figures. The heat exchanger cover 17 has an inlet opening 18, which is connected to an oil source of the oil circuit, and an outlet opening, which is connected to an oil sink of the oil circuit. List of reference symbols 1 internal combustion engine 2 crankcases 3 water jacket 4 wall 5 Recording area 6 Hole 7 Recess 8 Inlet 9 Procedure 10 guide rib 11 heat exchangers 12 support section 13 Breakthrough 14 inlet nozzles 15 outlet nozzles 16 screw 17 Heat exchanger cover 18 Inlet opening 19 Outlet opening 20 support surface 21 Hole 22 Sealing section 23 Circumferential sealing recess 24 screw 25 pens 26 Sealing element 27 gap

Claims

[1] Internal combustion engine comprising: a basic engine; a water jacket (3) formed in the base engine and through which a cooling fluid can flow, a recess (7) in a wall (4) of the base engine, which extends into the water jacket (3), a heat exchanger (11) which is arranged at least partially in the recess (7) and through which a second fluid can flow, so that thermal energy can be exchanged between the cooling fluid and the second fluid, a heat exchanger cover (17), via which the heat exchanger (11) is connected to a fluid circuit through which the second fluid can flow, characterized by , that the heat exchanger (11) is attached to the heat exchanger cover (17) and the heat exchanger cover (17) is attached to the base engine, and a pin (25) that positions the heat exchanger cover (17) and the base motor relative to each other. [2] Internal combustion engine according to claim 1, characterized by , that the heat exchanger cover (17) has a support surface (20) and that the heat exchanger (11) has a support section (12) which rests on the support surface (20) of the heat exchanger cover (17), wherein the pin (25) positions the heat exchanger cover (17) and heat exchanger (11) relative to one another. [3] Internal combustion engine according to one of claims 1 or 2, characterized by , that the base motor has a receiving surface (5), and that the heat exchanger cover (17) has a sealing section (22), wherein the sealing section (22) of the heat exchanger cover (17) rests on the receiving surface (5) of the base motor, so that a contact area between the sealing section (22) and the receiving surface (5) encloses the recess (7) in the wall (4) of the base motor. [4] Internal combustion engine according to claim 3, characterized bythat the sealing section (22) of the heat exchanger cover (17) comprises a sealing element (26) which is in contact with the receiving surface (5) of the base motor in the contact area, so that the recess (7) in the wall (4) of the base motor is enclosed by the sealing element (26). [5] Internal combustion engine according to one of claims 1 to 4, characterized by , that a positioning recess (6, 13, 21) is provided in the base engine, in the support section (12) of the heat exchanger (11) and in the heat exchanger cover (17), and that the pin (25) is arranged in the three positioning recesses (6, 13, 21), in particular is arranged without play in one, two or three of the three positioning recesses (6, 13, 21). [6] Internal combustion engine according to claim 5, characterized by that at least two of the three positioning recesses (6, 13, 21) have a different diameter. [7] Internal combustion engine according to one of claims 1 to 6, characterized by that the pin (25) is permanently connected to at least one of the base motor, the heat exchanger (11) and the heat exchanger cover (17), for example by gluing, welding or soldering. [8] Internal combustion engine according to one of claims 1 to 7, characterized by , that the heat exchanger (11) and the heat exchanger cover (17) are clamped together by a screw (16), wherein the screw (16) extends through an opening in the heat exchanger (11) into a counter thread in the heat exchanger cover (17) and the screw (16) is arranged in the opening with radial play. [9] Internal combustion engine according to one of claims 1 to 8, characterized by , that the heat exchanger cover (17) and the base motor are clamped together by a screw (24), wherein the screw (24) extends through an opening in the heat exchanger cover (17) into a counter thread in the base engine and the screw (24) is arranged with radial play in the opening. [10] Internal combustion engine according to one of claims 1 to 9, characterized by that the support section (12) of the heat exchanger (11) and the base motor are arranged at a distance from one another. [11] Internal combustion engine according to one of claims 1 to 10, characterized by that the pin (25) is designed in the form of a cylindrical pin, a conical pin, a grooved pin, a clamping pin or a clamping bush. [12] Internal combustion engine according to one of claims 1 to 11, characterized by that the pin (25) is designed as a dowel pin. [13] Internal combustion engine according to one of claims 1 to 12, characterized by that the heat exchanger cover (17) is designed as a cast part, in particular as a die-cast part.

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