EXHAUST GAS RECIRCULATION (EGR) COOLER AND ENGINE SYSTEM WITH SUCH A COOLER

Abstract

Exhaust gas recirculation (EGR) cooler (55), comprising: a pipe assembly (100) formed by stacking a plurality of pipes (110) in which exhaust gas flows; a cover plate (200) having a mounting portion (230) which is concave for securing the tube assembly (100) thereto; a baffle (300) attached to the tube assembly (100) and configured to adjust the flow of coolant from a cylinder block (20); an inlet cover (400) installed on a first side of an outer surface of the cover plate (200) for supplying the exhaust gas to each tube; an outlet cover (500) installed on a second side of the outer surface of the cover plate (200) for discharging the exhaust gas from each tube (110); wherein at least one coolant channel in which the coolant flows is formed between the plurality of tubes (110), wherein each tube (110) comprises: a cooling section (115) forming an exhaust gas passage; an inlet curved surface portion (113) shaped to be rounded from a first end of the cooling portion (115) toward the cover plate (200); and an outlet curved surface portion (119) shaped to be rounded from a second end of the cooling portion (115) toward the cover plate (200), an inlet slope portion (111) formed at one end of the inlet curved surface portion (113) to be opened to allow the exhaust gas to flow into the exhaust passage of the cooling portion (115); and an outlet slope portion (121) formed at one end of the outlet curved surface portion (119) to be opened to discharge the exhaust gas from the exhaust passage of the cooling portion (115), characterized by a first inclination portion (233) shaped to be inclined on a first side of the mounting portion (230); and a second inclination portion (235) formed to be inclined on a second side of the mounting portion (230), wherein the first inclination portion (233) is inclined from a first side of an inner surface of the cover plate (200) toward the pipe assembly (100), and the second inclination portion (235) is inclined from a second side of the inner surface of the cover plate (200) toward the pipe assembly (100), wherein the first inclination portion (233) is formed between a plurality of inflow openings (211) and the second inclination portion (235) is formed between a plurality of inflow openings (211), and wherein the tube assembly (100) is engaged with the cover plate (200), the inlet slope portion (111) of each tube (110) is inserted into an inflow opening (211), and the outlet slope portion (121) of each tube (110) is inserted into an outflow opening (221).

Description

BACKGROUND OF THE INVENTIONTechnical field

[0001] The present invention relates to an exhaust gas recirculation (EGR) cooler and an engine system having the same, in particular to an EGR cooler installed in a cylinder block and an engine system having the same. Description of the state of the art

[0002] Nitrogen oxide (NOx) contained in vehicle exhaust gases is a major air pollutant that needs to be reduced, and research has been conducted to reduce NOx emissions. An exhaust gas recirculation (EGR) system is a system installed in a vehicle to reduce harmful exhaust gases. Generally, NOx is increased when the air fraction in a mixer is high and combustion is good. Therefore, the EGR system remixes a portion (e.g., about 5% to 20%) of the exhaust gas exiting an engine in the mixer to reduce the amount of oxygen in the mixer and hinder combustion, thereby suppressing the formation of NOx.

[0003] A low-pressure exhaust gas recirculation (LP-EGR) system is a typical EGR system. The LP-EGR device recirculates exhaust gas that has passed through a turbine of a turbocharger to an intake port at a front stage of a turbocharger. The EGR system also includes a cooler. The recirculated exhaust gas is cooled by the cooler and supplied to a combustion chamber 21. The previously known EGR cooler includes a cooling structure installed in a separate housing. This requires various components, such as a nipple or the like, for connecting a recirculation line 52 through which a recirculation gas flows outside the housing. This also results in high manufacturing costs of a vehicle due to the elongation of the recirculation line 52. Since it is difficult to fix the EGR cooler in the vehicle, the EGR cooler housing shakes during driving, causing excessive vibration.

[0004] The information disclosed in this section is intended only to enhance the understanding of the background of the invention and may therefore contain information that does not constitute prior art already known in this country to a person of ordinary skill in the art.

[0005] Furthermore, document US 2017 / 0 205 153 A1 is known. It describes a heat exchanger device suitable for cooling recirculated exhaust gases. The device is characterized by a configuration that allows the heat exchanger to be installed in very small spaces, with the inlets and outlets of the recirculated exhaust gas not necessarily being aligned. Also characteristic is the internal configuration, which is based on a stack of flat tubes constructed using stamped and embossed sheets, forming a complex path for the fluid to be cooled.

[0006] Another known document is DE 10 2017 201 592 A1, concerning a primary plate for a cooling plate. PRESENTATION OF THE INVENTION

[0007] The present invention provides an exhaust gas recirculation (EGR) cooler that offers advantages in reducing the manufacturing costs of a vehicle. Furthermore, the present invention provides an exhaust gas recirculation (EGR) cooler with advantages in improving the cooling performance of exhaust gases.

[0008] An exhaust gas recirculation (EGR) cooler according to the invention has the features of claim 1.

[0009] The tube assembly may include a fastening element for securing the tube. The tube may include at least one cooling fin for cooling the exhaust gas and a guide projection for guiding the position of the cooling fin. At least one gap projection may be formed in the tube for adjusting a distance between adjacent tubes.

[0010] A bending portion may be formed on an edge of a flange portion formed on an outer periphery of the cover plate.

[0011] An engine system according to the invention comprises the features according to claim 8.

[0012] The tube assembly may include a fastening element for securing the tube. The tube may include at least one cooling fin for cooling the exhaust gas and a guide projection for guiding the position of the cooling fin. At least one gap projection may be formed in the tube for adjusting a distance between adjacent tubes.

[0013] A bending portion may be formed on an edge of a flange portion formed on an outer periphery of the cover plate.

[0014] According to the invention as described above, it is possible to increase the cooling efficiency of the exhaust gas because the EGR cooler can have a tube with a round, curved surface portion at both ends. Since the EGR cooler can be made of aluminum material, material costs and overall weight can be reduced, and cooling performance can be improved. SHORT DESCRIPTION OF THE CHARACTERS

[0015] The above and other features of the present invention will now be described in detail, with exemplary embodiments being illustrated in the accompanying drawings, which are included herein for illustrative purposes only and thus do not limit the present invention, and in which: Fig. 1 is a view illustrating an arrangement of an engine system to which an exhaust gas recirculation (EGR) cooler according to an exemplary embodiment of the present invention is applied; it is an engine; Fig. 2 is a partial perspective view illustrating a configuration of a cylinder block according to an exemplary embodiment of the present invention; Fig. 3 is a perspective view illustrating a configuration of an EGR cooler according to an exemplary embodiment of the present invention; Fig. 4 is a perspective view illustrating a configuration of a pipe according to an exemplary embodiment of the present invention; Fig. 5A and Fig. 5B are plan views of a configuration of a split protrusion according to an exemplary embodiment of the present invention; Fig. 6 and Fig. 7 are perspective views illustrating a configuration of a cover plate according to an exemplary embodiment of the present invention; Fig. 8 is a perspective view illustrating a configuration of a baffle according to an exemplary embodiment of the present invention; Fig. 9 and Fig. 10 are perspective views illustrating a configuration of an input cover and an output cover according to an exemplary embodiment of the present invention; and Fig. 11 is a drawing illustrating a relationship between a cover plate, an inlet cover, and an outlet cover according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] It is understood that the term “vehicle” or “vehicle” or other similar term as used herein includes motor vehicles in general, such as passenger cars including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, internal combustion engines, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative motor vehicles (e.g., fuels derived from resources other than petroleum).

[0017] Although the exemplary embodiment is described as using a plurality of units to perform the exemplary method, it is understood that the exemplary methods may also be performed by one or more modules. Furthermore, it is understood that the term controller / controller refers to a hardware device including a memory and a processor. The memory is configured to store the modules, and the processor is specifically configured to execute the modules to perform one or more processes, which are described in more detail below.

[0018] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes all combinations of one or more of the related listed items.

[0019] Unless expressly stated or clear from the context, as used herein, the term "approximately" is understood as within a range of normal tolerance in the art, for example, within 2 standard deviations of the mean. "Approximately" may be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 53%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless the context otherwise indicates, all numerical values ​​contained herein are modified by the term "approximately."

[0020] The present invention will now be described in more detail with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. As those skilled in the art would appreciate, the described exemplary embodiments can be modified in various ways without departing from the spirit or scope of the present invention. To clarify the present invention, parts are omitted regardless of description, and like reference numerals are used for the like parts throughout the specification. The size and thickness of each element are arbitrarily illustrated in the drawings, and the present invention is not necessarily limited thereto.

[0021] In the drawings, the thickness of layers, foils, panels, areas, etc. is exaggerated for clarity.

[0022] First, an engine system to which an exhaust gas recirculation (EGR) cooler according to an exemplary embodiment of the present invention is applied will be described with reference to Fig. 1 described. Fig. 1 is a view illustrating an arrangement of an engine system to which an exhaust gas recirculation (EGR) cooler according to an exemplary embodiment of the present invention is applied. And Fig. 2 is a partial perspective view illustrating a configuration of a cylinder block according to an exemplary embodiment of the present invention.

[0023] With reference to Fig. 1, an engine system according to an exemplary embodiment of the present invention may include an engine 10, an intake manifold 30, an exhaust manifold 40, and an exhaust gas recirculation (EGR) device 50. The engine 10 converts chemical energy into mechanical energy by combusting a mixture of fuel and air. The engine 10 may include a cylinder block 20, an intake manifold 13, a throttle valve 15, and an exhaust manifold 17. Fig. 1 and with reference to Fig. 2, at least one combustion chamber 21, an installation space 23, a coolant inlet 25 and a coolant outlet 27 can be formed in the cylinder block 20.

[0024] In particular, the combustion chamber 21 may be configured to generate drive torque by burning fuel. Although the drawings illustrate that the engine 10 has four combustion chambers 21, the number of combustion chambers 21 is not limited thereto. The installation space 23 may be formed on the cylinder block 20. The coolant inlet 25 may be formed on the inside of the installation space 23. The cooling coolant of the cylinder block may flow into the installation space 23 through the coolant inlet 25. The coolant outlet 27 may be formed on the inside of the installation space 23. The coolant flowing in the installation space 23 may be introduced into a water jacket (not shown) of the cylinder block via the coolant outlet 27. One side of the installation space 23 may be open.

[0025] Additionally, outside air can be supplied to the combustion chamber 21 via the intake manifold 13, flowing through the intake line. The throttle valve 15 can be installed in the intake line 30 upstream of the intake manifold 13. The amount of air supplied to the intake manifold 13 can be adjusted by adjusting an opening degree of the throttle valve 15. The exhaust manifold 17 can be connected to the combustion chamber 21. The exhaust gas generated in the combustion chamber 21 can be exhausted through the exhaust manifold 17. The engine 10 can be, but is not limited to, a gasoline direct injection (GDI) engine that injects fuel directly into the gasoline engine.

[0026] The intake line 30 can be connected to the intake manifold 13. An air cleaner 31, a compressor 32, and a charge air cooler 35 can be installed in the intake line 30. Outside air can be supplied to the intake manifold 13 via the intake line 30. The air cleaner 31 can be arranged in the intake line 30. The air cleaner 31 can be configured to filter outside air flowing into the intake line 30 from outside the vehicle. The engine system according to the present invention can further include a turbocharger 33 configured to supply compressed air to the combustion chamber 21.

[0027] Specifically, the turbocharger 33 may be configured to compress an intake gas (outside air + recirculation gas) flowing through the intake passage 30, and the compressed intake gas may be supplied to the combustion chamber 21. The turbocharger 70 may include a turbine 71 provided in the exhaust passage 40 and rotated by the exhaust gas discharged from the combustion chambers 21, and a compressor 72 rotated together with the turbine 71 and configured to compress the intake gas. The intercooler 35 may be installed in the intake passage 30 downstream of the compressor 32. The intercooler 35 may be configured to cool the high-temperature and high-pressure intake gas compressed by the compressor 32. The exhaust passage 40 may be connected to the exhaust manifold 17 and the EGR device 50. The turbine 34 and a catalyst 41 can be installed in the exhaust line 40.The exhaust gas discharged from the combustion chamber 21 may flow through the exhaust line 40. Furthermore, a portion of the exhaust gas may flow from the exhaust line 40 into the EGR device 50.

[0028] The catalyst 41 may be installed in the exhaust line 40 downstream of the turbine 34. The catalyst 41 may be configured to purify harmful substances in the exhaust gas exhausted from the combustion chamber 21. The catalyst 41 may be a three-way catalyst (TWC). The three-way catalyst may be configured to reduce CO, HC, and NOx in the exhaust gas of a gasoline engine. The three-way catalyst may be activated at a predetermined temperature or higher to convert carbon monoxide (CO) and hydrocarbons (HC) into harmless components through oxidation reactions, and NOx may be converted into harmless components through reduction reactions.

[0029] The EGR device 50 may include an EGR line 51, an EGR valve 53, and an EGR cooler 55. The EGR device 50 may be, but is not limited to, a low-pressure exhaust gas recirculation (LP-EGR) device. The EGR line 51 may branch from the exhaust line 40 downstream of the catalyst 41 and merge into the intake line 30 between the compressor 32 and the air cleaner 31. A portion of the exhaust gas (hereinafter referred to as "recirculation gas") flowing through the exhaust line 40 may flow into the EGR line 51. The exhaust gas flowing through the EGR line 51 may be supplied to the combustion chamber 21 via the intake line 30 and the intake manifold 13.

[0030] The EGR cooler 55 may be installed in the EGR line 51. Specifically, the EGR cooler 55 may be installed on the cylinder block 20. The EGR cooler 55 may be configured to cool the exhaust gas flowing through the EGR line 51. The EGR valve 53 may be installed in the EGR line 51 downstream of the EGR cooler 55. The EGR valve 53 may be installed in a position where the intake line 30 and the EGR line 51 are connected. The amount of recirculation gas can be adjusted by adjusting the opening degree of the EGR valve 53.

[0031] In the following, the EGR cooler according to an exemplary embodiment of the present invention will be described with reference to Fig. 3 to Fig. 11 described in detail. Fig. 3 is a perspective view illustrating a configuration of an EGR cooler according to an exemplary embodiment of the present invention. As shown in Fig. 3, the EGR cooler 55 according to an exemplary embodiment of the present invention may include a tube assembly 100, a cover plate 200, a baffle 300, an inlet cover 400, an outlet cover 500, an inlet flange 600, and an outlet flange 700.

[0032] In the description, the direction in which the intake cover 400 is installed on the base of the cover plate 200 is referred to as a first side, and the direction in which the exhaust cover 500 is installed is referred to as a second side. The pipe assembly 100 may be fixed in the installation space 23 formed in the cylinder block 20. The pipe assembly 100 may include a pipe 110 through which exhaust gas can flow and a fixing member 150. The pipe 110 and the fixing member 150 may be made of aluminum. A plurality of the pipes 110 may be stacked vertically, and an outer surface of a plurality of the pipes 110 may be surrounded by the fixing member 150 to fix the plurality of pipes 110. The fixing member 150 may be welded to the outer surface of the stacked pipes 110 to fix the pipes 110. A variety of fastening elements 150 can be provided.Coolant channels may be formed between the plurality of tubes 110 and between the tube assembly 100 and the inner surface of the installation space 23.

[0033] A detailed description of the tube 110 will be given with reference to Fig. 4 and Fig. 5. The cover plate 200 may be attached to the outer surface of the cylinder block 20 to close the installation space 23. In other words, the cover plate 200 may cover the open side of the installation space 23. The cover plate 200 may be made of aluminum. The tube assembly 100 may be attached to the cover plate 200. The cover plate 200 is described with reference to Fig. 6 and Fig. 7 described in detail.

[0034] At least a portion of the facing surfaces of the cover plate 200 and the tube assembly 100 may be spaced apart from each other, and a coolant passage may be formed between the spaced surfaces. In other words, the coolant passage may be formed between the plurality of tubes 110, between the inner surface of the tube assembly 100 and the installation space 23, and between the cover plate 200 and the spaced surfaces of the tube assembly 100. Coolant flowing through the coolant inlet 25 into the installation space of the cylinder block 20 may flow into the coolant passage. The exhaust gas flowing in the tube 110 may be cooled by the coolant flowing in the coolant passage.

[0035] The baffle 300 may be provided at both ends of the tube assembly 100. The baffles 300 may be made of aluminum. A flow of the coolant inflow to the coolant passage through the coolant inlet 25 of the cylinder block 20 may be adjusted by the baffle 300. The baffle 300 is described with reference to Fig. 8. The inlet cover 400 may be installed on a first side of the outer surface of the cover plate 200, and the outlet cover 500 may be installed on a second side of the outer surface of the cover plate 200. The inlet cover 400 and the outlet cover 500 may be made of aluminum. The inlet cover 400 and the outlet cover 500 may be described with reference to Fig. 9 to Fig. 11. The inlet flange 600 can be installed outside the inlet cover 400, and the outlet flange 700 can be installed outside the outlet 500. The inlet flange 600 and the outlet flange 700 can be made of aluminum. The inlet flange 600 and the outlet flange 700 can be connected to the EGR line 51.

[0036] The following describes a flow of exhaust gas flowing through the EGR line 51. The exhaust gas flowing through the EGR line 51 can flow into the tubes 110 through the inlet flange 600, the inlet cover 400, and the cover plate 200. The exhaust gas can be cooled by the coolant flowing through the coolant passage. The exhaust gas can then be reintroduced into the EGR line 51 via the cover plate 200, the outlet cover 500, and the outlet flange 700.

[0037] With reference to Fig. 4 on Fig. 11, the components of the EGR cooler 55 according to an exemplary embodiment of the present invention are described in more detail.

[0038] Fig. 4 is a perspective view illustrating a configuration of a pipe according to an exemplary embodiment of the present invention. And Fig. 5A and Fig. 5B are plan views of a configuration of a split protrusion according to an exemplary embodiment of the present invention. Referring to Fig. 4, each tube 110 may be formed in a substantially rectangular shape. The exhaust gas may flow within each tube 110. A plurality of tubes 110 may be stacked to form a tube assembly 100 (see Fig. 3).

[0039] Each tube 110 may be formed by assembling a first tube partition 130 and a second tube partition 140, and an exhaust passage is formed therein. The tube 110 may include an inlet slope portion 111, an inlet curved surface portion 113, a cooling portion 115, a cooling fin 117, an outlet curved surface portion 119, an outlet slope portion 121, and a gap projection 123. An exhaust passage may be formed in the cooling portion 115. An inlet curved surface portion 113 may be formed to be rounded from a first end of the cooling portion 115 toward the cover plate 200. And the outlet curved surface portion 123 may be shaped to be rounded from a second end of the cooling portion 115 toward the cover plate 200.An inlet slope portion 111 may be formed at one end of the openable inlet curved surface portion 113 to allow the exhaust gas to flow into the exhaust passage of the cooling portion 115. And an outlet slope portion 121 may be formed at one end of the outlet curved surface portion 123 to be opened to discharge the exhaust gas from the exhaust passage of the cooling portion 115.

[0040] A cross-section of the inlet slope portion 111 may be formed in a substantially rectangular shape. The inlet slope portion 111 may be shaped to be inclined at a predetermined angle in the direction opposite to the cover plate 200. The inlet slope portion 111 may be opened to allow the exhaust gas to flow from the inlet cover 400 into the pipe 110. The exhaust gas may flow through the inlet slope portion 111 into the exhaust passage of the pipe 110. The inlet curved surface portion 113 of the inlet may be formed in a rounded shape. The exhaust gas flowing into the inlet slope portion 111 through the inlet curved surface portion 113 may flow into the cooling portion 115. Since the inlet curved surface portion 113 has a rounded shape, the flow resistance of the exhaust gas can be reduced and the exhaust gas can flow more smoothly into the cooling portion 115.

[0041] The cooling portion 115 may be formed in a central portion of the tube 110. The cooling fin 117 may be formed in the cooling portion 115. A plurality of cooling fins 117 may be formed and may be spaced apart from each other, and the cooling fin 117 may be formed in a wavy shape. The cooling fin 117 may be formed integrally with the cooling portion 115. Alternatively, the cooling fin 117 may be provided separately from the cooling portion 115, and the cooling fin 117 and the cooling portion 115 may be fixed by welding or joining. Since the cooling fin 117 may be formed in the cooling portion 115, the heat dissipation area of ​​the exhaust gas flowing in the cooling portion 115 can be increased. Accordingly, the cooling performance of the exhaust gas flowing in the tube 110 can be improved.

[0042] The guide projection 118 for guiding the position of the cooling fin 117 may be formed on both sides of the inner surface of the cooling section 115. The guide projection 118 may be formed in pairs adjacent to the cooling fin 117. In addition, the guide projection 118 may be provided on at least one of the inner surfaces of the first tube partition wall 130 and the inner surface of the second tube partition wall 140. The guide projection 118 may protrude or extend toward the inside of the cooling section 115. The guide projection 118 may protrude inside or outside the cooling section 115.

[0043] The outlet curved surface portion 119 may be formed in a rounded shape. The exhaust gas flowing in the cooling section 115 can be exhausted through the outlet curved surface portion 119 to the outlet slope portion 121. Since the outlet curved surface portion 119 has a rounded shape, the flow resistance of the exhaust gas can be reduced and the exhaust gas can be discharged more smoothly. The cross section of the outlet slope portion 121 may be formed in a substantially rectangular shape. The outlet slope portion 121 may be formed to be inclined at a predetermined angle in the direction opposite to the cover plate 200. The outlet slope portion 121 may be open to discharge the exhaust gas circulating in the cooling section 115. The exhaust gas cooled in the cooling section 115 can be exhausted through the outlet curved surface section 119 and the outlet slope section 121 to the outlet cover 500.

[0044] The gap projection 123 can be formed on the outer surfaces of the first pipe partition wall 130 or the second pipe partition wall 140. Fig. 4 shows four gap projections 123, which are only an example, and a plurality of gap projections 123 may be provided. The gap projection 123 may be formed separately from the tube 110 by welding or integrally with the tube 110. The gap projection 123 is shown in the Fig. 5A-5B, circular or elliptical, but not limited thereto. The gap projection 123 can adjust the flow rate of the coolant flowing in the coolant channel.

[0045] As in Fig. As shown in Figure 5A, when the gap projection 123 is formed in a circular shape, the coolant can flow through the coolant channel formed between the adjacent tubes 110. Since the coolant flows from upstream to downstream of the gap projection 123 and the coolant is formed in a swirl shape downstream of the gap projection 123, the coolant can be temporarily stagnated downstream of the gap projection 123 at this time.

[0046] As in Fig. As shown in Figure 5B, when the gap protrusion 123 is formed in an elliptical shape with a longer length in the coolant flow direction, the coolant flow past the gap protrusion 123 and the coolant flow before passing through the gap protrusion 123 can be adjusted in the same way. Furthermore, a distance between the plurality of tubes 110 can be adjusted by the gap protrusion 123. In other words, when the plurality of tubes 110 are stacked to form the tube assembly 100, the distance between the plurality of tubes 110 can be adjusted by the gap protrusion 123 and the cross-sectional area formed between the plurality of tubes 110. Accordingly, the cooling performance of the exhaust gas circulating in the tube 110 can be improved.

[0047] As described above, the pipe 110 can be formed by assembling the first pipe partition 130 and the second pipe partition 140. The first pipe partition 130 can be inserted into the second pipe partition 140, and the contact surface of the first pipe partition 130 and the second pipe partition 140 can be welded to form the pipe 110. The first pipe partition 130 and the second pipe partition 140 can be tightly fitted to minimize a gap between a contact surface 131 of the first pipe partition 130 and a contact surface 141 of the second pipe partition 140. By minimizing the gap as described above, it may be possible to reduce the material for welding to fill the gap. Therefore, the production cost of the pipe 110 and the weight of the pipe 110 can be reduced. In addition, the exhaust gas flowing inside the pipe 110 can be prevented from escaping to the outside.

[0048] Fig. 6 and Fig. 7 are perspective views illustrating a structure of a cover plate according to an exemplary embodiment of the present invention. Fig. 6 is a perspective view illustrating an outer surface of the cover plate 200 according to an exemplary embodiment of the present invention, and Fig. 7 is a perspective view illustrating an inner surface of the cover plate 200 according to an exemplary embodiment of the present invention.

[0049] The cover plate 200 according to an exemplary embodiment of the present invention can be attached to an outer surface of the cylinder block 20 and cover the installation space 23. The tube assembly 100 can be attached to an inner surface of the cover plate 200. The inlet cover 400 can be attached to a first side of the outer surface of the cover plate 200, and the exhaust cover 500 can be attached to a second side of the outer surface of the cover plate 200. The cover plate 200 can be manufactured by pressing the metal plate.

[0050] With reference to Fig. 6 and Fig. 7, the cover plate 200 may include an inlet portion 210, an outlet portion 220, a mounting portion 230, and a flange portion 240. Referring to Fig. 6, the inlet portion 210 may be formed on a first side of the outer surface of the cover plate 200. The inlet portion 210 may be inclined at a predetermined angle from a first side of the cover plate 200 toward the tube assembly 100. The inlet portion 210 may include an inflow opening 211 and a positioning protrusion 213.

[0051] The inlet opening 211 may be formed in the same shape as the inlet slope portion 111 of the tube 110. In addition, the number of inlet openings 211 is equal to the number of tubes 110 of the tube assembly 100. The exhaust gas flow from the inlet cover 400 may be distributed among the inlet openings and may flow into each tube 110. The positioning projection 213 may protrude toward the outside of the cover plate 200 (e.g., opposite side of the installation space) and be formed adjacent to the inlet opening 211. Fig. 6 shows three positioning protrusions 213, but this is only an example, and a plurality of positioning protrusions 213 may be provided. The number of positioning protrusions 213 may be equal to the number of positioning grooves 411 of the inlet cover 400, which will be described later. The positioning protrusion 213 can guide the locking position of the inlet cover 400.

[0052] The outlet portion 220 may be formed on a second side of the outer surface of the cover plate 200. The outlet portion 220 may be inclined at a predetermined angle from a first side of the cover plate 200 toward the tube assembly 100. The exhaust gas cooled in the tubes 110 may be exhausted to the outside through the outlet portion 220. The outlet portion 220 may have an outlet opening 221 and a positioning protrusion 223. The outlet opening 221 may be formed in the same shape as the outlet slope portion 121 of the tube 110. The number of outlet openings 221 is equal to the number of tubes 110 of the tube assembly 100. The exhaust gas cooled in the tubes 110 may be exhausted through the outlet opening 221 to the outlet cover 500.

[0053] The positioning projection 223 may be formed adjacent to the outflow opening 221. Fig. 6 shows three positioning protrusions 223, but this is only an example, and a plurality of positioning protrusions 223 may be provided. The number of positioning protrusions 223 may be equal to the number of engagement holes 511 of the inlet cover 400, which will be described later. Since the inlet portion 210 and the outlet portion 220 are inclined, the coolant passage formed between the tube assembly 100 and the cover plate 200 can be located near the inlet cover 400 and the outlet cover 500. Accordingly, the cooling performance of the exhaust gas flowing into the tubes 110 can be improved.

[0054] Furthermore, the distribution of the exhaust gas to each tube 110 of the tube assembly 100 and the exhaust gas discharged from the tube 110 can be facilitated. When the coolant channel and the inlet cover 400 and the outlet cover 500 are adjacent to each other as described above, the inlet cover 400 and the outlet cover 500 can be more easily cooled, and the durability of the inlet cover 400 and the outlet cover 500 can be improved.

[0055] With reference to Fig. 7, the mounting portion 230 may be concave in overall view and formed on an inner surface of the cover plate 200. The mounting portion 230 may include a central portion 231, a first inclination portion 233, and a second inclination portion 235. The tube assembly 100 may be fixed in the mounting portion 230. The first inclination portion 233 may be inclined from a first side of the inner surface of the cover plate 200 toward the tube assembly 100. The first inclination portion 233 may be formed between the plurality of inflow openings 211. When the tube assembly 100 is engaged with the cover plate 200, the inlet inclination portion 111 of each tube 110 may be inserted into each inflow opening 211.

[0056] The second slope portion 235 may be sloped from a second side of the inner surface of the cover plate 200 toward the tube assembly 100. The first slope portion 233 and the second slope portion 235 may be formed symmetrically around the central portion 231. The second slope portion 235 may be formed between the plurality of outflow openings 221. When the tube assembly 100 is engaged with the cover plate 200, the outlet slope portion 121 of each tube 110 may be inserted into each outflow opening 221. When the tube assembly 100 is secured in the cover plate 200, the central portion of the tube 110 may be positioned in the central portion, the inlet slope portion 111 may be inserted into the inflow opening 211, and the outlet slope portion 121 may be inserted into the outflow opening 221.

[0057] The flange portion 240 may be formed on an outer periphery of the cover plate 200. The cover plate 200 and the cylinder block 20 may be engaged by the flange portion 240. The flange portion 240 may include a bent portion 241 and an engagement hole 243. The bent portion 241 may be formed at the edge of the flange portion 240. In other words, the bent portion 241 may be bent outward from the outermost portion of the flange portion 240. The rigidity of the cover plate 200 can be increased by the bent portion 241. The engagement hole 243 may be formed on the flange portion 240. A plurality of engagement holes 243 may be provided, and the number of engagement holes 243 is equal to the number of engagement holes (not shown) formed in the cylinder block.After mounting the cover plate 200 on the cylinder block 20, a snap-in bolt can be screwed through the cover engagement opening 243 (e.g., hole) into the snap-in opening (e.g., hole) of the cylinder block to connect the cover plate 200 to the cylinder block 20.

[0058] Fig. 8 is a perspective view illustrating a structure of a baffle according to an exemplary embodiment of the present invention. Referring to Fig. 8, the baffle 300 according to an exemplary embodiment of the present invention has a substantially rounded shape and can be installed at a first end of the tube assembly 100 (e.g., at the inlet side where the coolant flows in). In other words, the baffle 300 can be configured to correspond to the inlet curved surface portion 113 of the tube 110.

[0059] The baffle 300 may include an insertion portion 310, a welding portion 320, and a through portion 330. The insertion portion 310 may be bent toward the cover plate 200 at both ends of the baffle 300. The welding portion 320 may be formed in a rounded shape (or partially arcuate). When the baffle 300 is engaged with the tube assembly 100, the insertion portions 310 may be inserted into the outside of the tube assembly 100, and then the welding portion 320 may be welded to the tube assembly 100.

[0060] The passage portion 330 is an opening formed in the baffle 300 and the welded portions 320. When the baffle 300 engages the tube assembly 100, the passage portion 330 can be positioned to correspond to the coolant passage formed between the adjacent tubes 110. Specifically, ten passage portions 330 can be formed. The coolant flowing through the coolant inlet 25 of the cylinder block 20 can flow into the coolant passage through the passage portion 330. Because the passage portions 330 are positioned to correspond to the coolant passages, the coolant can flow more smoothly into the coolant passage.

[0061] Fig. 9 and Fig. 10 are perspective views illustrating a structure of an inlet cover and an outlet cover according to an exemplary embodiment of the present invention. And Fig. 11 is a diagram illustrating a relationship between a cover plate, an inlet cover, and an outlet cover according to an exemplary embodiment of the present invention. The inlet cover and the outlet cover may be symmetrically shaped.

[0062] With reference to Fig. 9, the cross-section of the inlet cover 400 may have a substantially trapezoidal shape, and the inlet cover may be disposed on a first side of the outer surface of the cover plate 200. The inlet cover 400 may include a cover engagement portion 410 and a flange engagement portion 420. The cover engagement portion 410 may be attached to a first side of the cover plate 200 and may be inclined corresponding to the inlet portion 220 of the cover plate 200. The inlet cover 400 may be engaged with the cover plate 200 through the cover engagement portion 410.

[0063] With reference to Fig. 10, at least one engagement opening 411 may be formed in the cover engagement portion 410 to correspond to the positioning protrusion 213 formed in the inlet portion 210 of the cover plate 200. When the inlet cover 400 is engaged with the inlet portion 210 of the cover plate 200, the position of the inlet cover 400 may be guided by the positioning protrusion 213 and the engagement opening 411.

[0064] With reference to Fig. 11, the engaging hole 411 of the intake cover 400 may be inserted into the positioning protrusion 213 of the cover plate 200, and then the intake cover 400 and the cover plate 200 may be coupled by welding. An intake flange 600 may be attached to the flange engaging portion 420. A pipe opening 421 for engaging the EGR passage 51 may be formed in the flange engaging portion 420. The exhaust cover 500 may have a cover engaging portion 510 and a flange engaging portion 520. The cover engaging portion 510 may be attached to a second side of the cover plate 200 and may be inclined corresponding to the outlet portion 220 of the cover plate 200. The exhaust cover 500 may be engaged with the cover plate 200 through the cover engaging portion 510.

[0065] With reference to Fig. 10, at least one engagement hole 511 may be formed in the cover engagement portion 510 to correspond to the positioning protrusion 223 formed in the outlet portion 220 of the cover plate 200. When the outlet cover 500 is engaged with the outlet portion 220 of the cover plate 200, the position of the outlet cover 500 may be guided by the positioning protrusion 223 and the engagement hole 511.

[0066] With reference to Fig. 11, the engagement hole 511 of the outlet cover 500 may be inserted into the positioning protrusion 223 of the cover plate 200, and then the inlet cover 400 and the cover plate 200 may be coupled by welding. An outlet flange 700 may be attached to the flange engagement portion 520. A pipe opening 521 for engaging the EGR passage 51 may be formed in the flange engagement portion 520.

[0067] Because the cover engagement portions 410 and 510 are inclined, the distance between the coolant flowing in the coolant passage and the inlet cover 400 and the outlet cover 500 can be reduced. This allows the inlet cover 400 and the outlet cover 500 to be cooled more easily and improves durability. As described above, the tube 110, the fastener 150, the cover plate 200, the baffle 300, the inlet cover 400, the outlet cover 500, the inlet flange 600, and the outlet flange 700 can be made of aluminum.

[0068] Since the above-described parts are made of aluminum with higher thermal conductivity than conventional materials, the cooling efficiency of the exhaust gas circulating in the pipe 110 is increased, thus improving the vehicle's fuel consumption. Since the cost of aluminum is cheaper than conventional materials, it is possible to reduce material costs. Since aluminum is lighter than conventional materials, the overall weight of the EGR cooler 55 can be reduced.

[0069] The following describes in detail the operation of the EGR cooler 55 according to an exemplary embodiment of the present invention. The exhaust gas flowing in the EGR passage 51 can flow through the inlet flange 600 and the inlet cover 400 into the inlet portion 210 of the cover plate 200. The exhaust gas flowing in the inlet portion 210 of the cover plate 200 can be distributed among the plurality of tubes 110 and flow into the plurality of tubes 110. At the same time, some coolant from a water jacket (not shown) can flow into the installation space 23 through the coolant inlet 25.

[0070] The exhaust gas flowing through the plurality of tubes 110 can be heated by heat exchange with the coolant flowing through the coolant passage, and the temperature of the exhaust gas can be lowered. The exhaust gas, which has a lower temperature due to the heat exchange with the coolant, can be exhausted from the plurality of tubes 110 to the EGR passage 51 via the outlet portion of the cover plate 200, the outlet cover 500, and the outlet flange 700. List of reference symbols 10 Engine 13 Intake manifold 15 Throttle valve 17 exhaust manifold 20 cylinder block 21 Combustion chamber 23 Installation space 25 Coolant inlet 27 Coolant outlet 30 intake line 31 air filters 32 compressors 33 turbochargers 34 turbines 35 intercooler 40 exhaust pipe 41 Catalyst 50 EGR device 51 EGR line 53 EGR valve 55 EGR cooler 100 pipe arrangement 110 pipe 111 Inlet slope section 113 Inlet curved surface section 115 Cooling section 117 Cooling fin 118 lead 119 Outlet curved surface section 121 run-out slope section 123 gap projection 130 first pipe partition wall 131, 141 contact surface 140 second pipe partition wall 150 fastening element 200 cover plate 210 Inlet part 211 Inlet opening 213, 223 Position advantage 220 run-off section 221 Outlet opening 230 assembly section 231 Middle section 233, 235 incline section 240 flange section 241 Bending section 243 Access opening 300 baffle 310 insertion section 320 welding section 330 through section 400 inlet cover 410 Cover snap-in area 411 Snap-in panel 420 flange engagement area 500 spout lids 510 Cover snap-in area 511 Access opening 520 Flange engagement section 600 inlet flange 700 outlet flange

[0071] Although this invention has been described in connection with what are presently considered exemplary embodiments, it is to be understood that the invention is not limited to the exemplary embodiments disclosed. On the contrary, it is intended to cover various changes and equivalent modifications included within the spirit and scope of the appended claims.

Claims

[1] Exhaust gas recirculation (EGR) cooler (55), comprising: a pipe assembly (100) formed by stacking a plurality of pipes (110) in which exhaust gas flows; a cover plate (200) having a mounting portion (230) which is concave for securing the tube assembly (100) thereto; a baffle (300) attached to the tube assembly (100) and configured to adjust the flow of coolant from a cylinder block (20); an inlet cover (400) installed on a first side of an outer surface of the cover plate (200) for supplying the exhaust gas to each tube; an outlet cover (500) installed on a second side of the outer surface of the cover plate (200) for discharging the exhaust gas from each tube (110); wherein at least one coolant channel in which the coolant flows is formed between the plurality of tubes (110), wherein each tube (110) comprises: a cooling section (115) forming an exhaust gas passage; an inlet curved surface portion (113) shaped to be rounded from a first end of the cooling portion (115) toward the cover plate (200); and an outlet curved surface portion (119) shaped to be rounded from a second end of the cooling portion (115) toward the cover plate (200), an inlet slope portion (111) formed at one end of the inlet curved surface portion (113) to be opened to allow the exhaust gas to flow into the exhaust passage of the cooling portion (115); and an outlet slope portion (121) formed at one end of the outlet curved surface portion (119) to be opened to discharge the exhaust gas from the exhaust passage of the cooling portion (115), characterized by a first inclination portion (233) shaped to be inclined on a first side of the mounting portion (230); and a second inclination portion (235) formed to be inclined on a second side of the mounting portion (230), wherein the first inclination portion (233) is inclined from a first side of an inner surface of the cover plate (200) toward the pipe assembly (100), and the second inclination portion (235) is inclined from a second side of the inner surface of the cover plate (200) toward the pipe assembly (100), wherein the first inclination portion (233) is formed between a plurality of inflow openings (211) and the second inclination portion (235) is formed between a plurality of inflow openings (211), and wherein the tube assembly (100) is engaged with the cover plate (200), the inlet slope portion (111) of each tube (110) is inserted into an inflow opening (211), and the outlet slope portion (121) of each tube (110) is inserted into an outflow opening (221). [2] The exhaust gas recirculation (EGR) cooler (55) of claim 1, wherein the tube assembly (100) includes a fastener (150) for securing the tube (110). [3] An exhaust gas recirculation (EGR) cooler (55) according to claim 1 or 2, wherein each tube (110) comprises: At least one cooling fin (117) for cooling the exhaust gas; and a guide projection (118) for guiding a position of the cooling fin (117). [4] Exhaust gas recirculation (EGR) cooler (55) according to one of the preceding claims, further comprising: at least one gap projection (123) formed in each tube (110) to adjust a distance between adjacent tubes (110) of the plurality of tubes (110). [5] Exhaust gas recirculation (EGR) cooler (55) according to one of the preceding claims, further comprising: a bending portion (241) formed on an edge of a flange portion (240) formed on an outer periphery of the cover plate (200). [6] Exhaust gas recirculation (EGR) cooler (55) according to one of the preceding claims, further comprising: an inlet cover engagement portion formed in the inlet cover (400) corresponding to the first inclination portion (233), and an outlet cover engagement portion formed in the outlet cover (500) corresponding to the second inclination portion (235). [7] Exhaust gas recirculation (EGR) cooler (55) according to any one of the preceding claims, further comprising: a positioning projection (213; 223) formed in the cover plate (200); and an engagement opening (243) formed in the inlet cover (400) and the outlet cover (500) corresponding to the positioning projection (213; 223), wherein the inlet cover and the outlet cover are guided by inserting the positioning projection (213; 223) into the engagement opening (243). [8] Engine system, comprising: an engine (10) having a cylinder block (20) in which an installation space (23) is formed, a coolant inlet (25) through which coolant flows into the installation space (23), and a coolant outlet (27) through which the coolant is expelled from the installation space (23); an intake line (30) in which outside air supplied to the engine (10) flows; an exhaust pipe (40) in which exhaust gas generated in the engine (10) flows; an exhaust gas recirculation line (51) branching off from the exhaust line (40) and integrated into the intake line (30); and an EGR cooler (55) configured to cool the exhaust gas flowing through the EGR line (51); wherein the EGR cooler (55) comprises: a pipe assembly (100) formed by stacking a plurality of pipes (110) in which exhaust gas flows, the pipe assembly (100) being fixed in the installation space; a cover plate (200) having a mounting portion (230) which is concavely formed to fix the pipe assembly (100) thereon, the cover plate (200) covering the installation space (23); a baffle (300) attached to the tube assembly (100) and configured to adjust the coolant flow from the coolant inlet (25); an inlet cover (400) installed on a first side of the cover plate (200) for supplying the exhaust gas to the pipe (110); and an outlet cover installed on a second side of the cover plate (200) for discharging the exhaust gas from the pipe (110); wherein coolant channels in which the coolant flows are formed between the tube arrangement (100) and the installation space (23), between each of the plurality of tubes (110) and between the tube arrangement (100) and the cover plate (200), further comprising: a first inclination portion (233) shaped to be inclined on a first side of the mounting portion (230); and a second inclination portion (235) formed to be inclined on a second side of the mounting portion (230), wherein each tube (110) comprises: a cooling section (115) forming an exhaust gas passage; an inlet curved surface portion (113) shaped to be rounded from a first end of the cooling portion (115) toward the cover plate (200); and an outlet curved surface portion (119) shaped to be rounded from a second end of the cooling portion (115) toward the cover plate (200), an inlet slope portion (111) formed at one end of the inlet curved surface portion (113) to be opened to allow the exhaust gas to flow into the exhaust passage of the cooling portion (115); and an outlet slope portion (121) formed at one end of the outlet curved surface portion (119) to be opened to discharge the exhaust gas from the exhaust passage of the cooling portion (115), wherein the first slope portion (233) is sloped from a first side of an inner surface of the cover plate (200) toward the pipe assembly (100), and the second slope portion (235) is sloped from a second side of the inner surface of the cover plate (200) toward the pipe assembly (100), wherein the first inclination portion (233) is formed between a plurality of inflow openings (211) and the second inclination portion (235) is formed between a plurality of inflow openings (211), and wherein the tube assembly (100) is engaged with the cover plate (200), the inlet slope portion (111) of each tube (110) is inserted into an inflow opening (211), and the outlet slope portion (121) of each tube (110) is inserted into an outflow opening (221). [9] The engine system of claim 8, wherein the tube assembly (100) includes a fastener (150) for securing the tube (110). [10] An engine system according to claim 8 or 9, wherein each tube (110) comprises: At least one cooling fin (117) for cooling the exhaust gas; and a guide projection (118) for guiding a position of the cooling fin (117). [11] Engine system according to any one of claims 8-10, further comprising: at least one gap projection (123) formed in each tube (110) to adjust a distance between adjacent tubes (110) of the plurality of tubes (110). [12] Engine system according to any one of claims 8-11, further comprising: a bending portion (241) formed on an edge of a flange portion (240) formed on an outer periphery of the cover plate (200). [13] Engine system according to any one of claims 8-12, further comprising: an inlet cover engagement portion formed in the inlet cover (400) corresponding to the first inclination portion (233), and an outlet cover engagement portion formed in the outlet cover (500) corresponding to the second inclination portion (235). [14] Engine system according to any one of claims 8-13, further comprising: a positioning projection (213; 223) formed in the cover plate (200); and an engagement opening (243) formed in the inlet cover (400) and the outlet cover (500) corresponding to the positioning projection (213; 223), wherein the inlet cover (400) and the outlet cover (500) are guided by inserting the positioning projection (213; 223) into the engagement opening (243).

Images