JP2005083270A - Heat accumulator of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a deterioration in filling efficiency in a combustion chamber of an internal combustion engine. <P>SOLUTION: The heat accumulator of an internal combustion engine is equipped with a heat accumulating tank 8 for storing cooling water (hot water) heated to high temperatures by engine operation of the internal combustion engine when an engine of an internal combustion engine is stopped. When or before restarting the internal combustion engine, the high temperature cooling water stored in the heat accumulating tank 8 is supplied to warm up the internal combustion engine. An outer pipe 28 of an intake duct 24 having a double-pipe structure which is a passage for air supplied to the combustion chamber 13 is taken as the heat accumulating tank 8. Accordingly, even if the quantity of heat discharged to a space around the surface of the internal combustion engine 1 body is increased, resin 27 (a heat insulator) forming the outside of the heat accumulating tank 8 can intercept the heat discharged from the internal combustion engine 1 body, thereby suppressing the deterioration in the filling efficiency caused by excessive heating of air supplied to the combustion chamber 13. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat storage device for an internal combustion engine having a heat storage tank and an intake passage.

  During the cold start of the internal combustion engine, the temperature of the combustion chamber and cooling water has decreased, the temperature of the intake port wall surface remains low, and the atomization of the fuel injected from the fuel injection valve into the intake port is insufficient It becomes. In this case, the fuel supplied to the internal combustion engine and the intake air cannot be sufficiently mixed. For this reason, in a state where the warm-up immediately after starting the internal combustion engine is insufficient, fuel consumption and emission performance are deteriorated as compared with a state where the internal combustion engine is sufficiently warmed up.

  Therefore, as shown in Patent Document 1, a high-temperature storage tank that stores high-temperature cooling water is provided, and the high-temperature storage tank stores the heat storage tank at a location where the temperature needs to be increased, such as a cylinder head, prior to starting the internal combustion engine. There is a technique for promoting warm-up of the internal combustion engine by supplying the cooling water.

Japanese Patent Laid-Open No. 2002-138832

  After the warm-up operation of the internal combustion engine is finished, for example, in a high load state of the internal combustion engine, the amount of heat released from the outer surface of the internal combustion engine body to the surrounding space increases. Since the heat storage tank disclosed in Patent Document 1 is installed in contact with the intake side of the internal combustion engine body, the heat transfer tank is transferred from the outer surface of the internal combustion engine body in the portion of the intake passage facing the internal combustion engine body. Heat can be cut off. Therefore, it is possible to suppress excessive heating of the intake air that passes through the intake passage and is fed into the combustion chamber, so that it is possible to suppress a decrease in charging efficiency in the combustion chamber of the internal combustion engine.

  However, since the heat released from the outer surface of the internal combustion engine body is transferred to the intake passage using air as a medium, in the configuration of Patent Document 1, the heat released from the outer surface of the internal combustion engine body to the surrounding space is used. Only part of the heat transfer can be suppressed. Therefore, the reduction in the charging efficiency of the intake air due to the temperature rise of the intake air cannot be sufficiently suppressed.

  The present invention has been made in view of the problems of the prior art, and insulates a portion of the intake passage that receives heat released from the outer surface of the internal combustion engine body using a heat storage tank. Thus, without increasing the number of parts, the intake passage is prevented from being heated excessively due to the heat from the internal combustion engine body, and the reduction of the charging efficiency of the intake air in the combustion chamber of the internal combustion engine is suppressed. Is an issue.

  In order to solve the above problems, the present invention employs the following means. In a heat storage device for an internal combustion engine comprising an intake passage of the internal combustion engine and a heat storage tank for storing a heat medium, covering at least a part of the entire circumference in the longitudinal direction of the intake passage with a heat insulating material of the heat storage tank. Features.

  According to a second aspect of the present application, in the heat storage device for an internal combustion engine according to claim 1, at least a part of the entire circumference of the intake passage is covered with a storage portion of the heat storage tank. .

  According to a third aspect of the present invention, in the heat storage device for an internal combustion engine according to the first or second aspect, the present invention is an air intake duct that communicates an air cleaner and a surge tank.

  According to a fourth aspect of the present application, in the heat storage device for an internal combustion engine according to claim 2 or 3, the inlet of the heat storage tank is provided so as to face the circumferential direction of the heat storage tank. .

  According to a fifth aspect of the present application, in the heat storage device for an internal combustion engine according to any one of claims 1 to 4, at least a part of the heat storage tank or at least a part of the intake passage is formed of a resin. It is characterized by that.

  In the heat storage device for an internal combustion engine according to the first invention, at least a part of the entire circumference in the longitudinal direction of the intake passage is covered with the heat insulating material of the heat storage tank. Therefore, the heat released from the outer surface of the internal combustion engine body in the intake passage can be blocked by the heat insulating material of the heat storage tank, so that the filling efficiency in the combustion chamber in the internal combustion engine body is reduced without increasing the number of parts. Can be further suppressed.

  In the heat storage device for an internal combustion engine according to the second aspect of the invention, at least a part of the entire circumference of the intake passage is covered with the storage portion of the heat storage tank. Therefore, since the area occupied by the heat storage tank in the space between the internal combustion engine body and the intake duct can be reduced, the space between the internal combustion engine body and the intake duct can be increased.

  In the heat storage device for an internal combustion engine according to the third aspect of the invention, the intake passage is an intake duct that communicates the air cleaner and the surge tank. Therefore, the entire intake air is located within the heat insulating material of the heat storage tank, and heat transfer from the outer surface of the internal combustion engine body to the intake passage can be reliably blocked, so that in the combustion chamber in the internal combustion engine body A decrease in filling efficiency can be reliably suppressed.

  In the heat storage device for an internal combustion engine according to the fourth invention, the inlet of the heat storage tank is provided toward the circumferential direction of the heat storage tank. Therefore, since the cooling water flowing into the heat storage tank has a circumferential flow, the cooling water stored in the heat storage tank can be given to the entire cooling water in the heat storage tank. Can be prevented from stagnation.

  In the heat storage device for an internal combustion engine according to the fifth aspect, the heat storage tank and at least a part of the intake passage are formed of resin. Therefore, it can be made lighter than a heat storage tank and an intake duct formed of metal.

  First, a heat storage device for an internal combustion engine according to a first embodiment will be described with reference to FIGS. 1 to 13.

  As shown in FIG. 1, the internal combustion engine body 1 includes a cylinder head 2 and a cylinder block 4. The cylinder head 2 has a cylinder head side cooling water passage 3, and the cylinder block 4 has a cylinder block side cooling water passage 5. Is provided. The cylinder head side cooling water passage 3 and the cylinder block side cooling water passage 5 are communicated with each other. The cooling water cools the internal combustion engine body 1 by flowing through the cylinder head side cooling water passage 3 and the cylinder block side cooling water passage 5, while being heated by receiving the heat of the internal combustion engine body 1. The cylinder head side cooling water passage 3 is communicated with a heat storage tank 8 through a cooling water passage 6 and a cooling water passage 7.

  The cooling water is boosted by an electric water pump 9 installed in the middle of the cooling water path 6 and sent out to the cooling water path 6 on the heat storage tank 8 side downstream of the electric water pump 9. Furthermore, the cooling water circulates in the order of the inlet 10, the outlet 11, the cooling water path 7, the cylinder head side cooling water path 3, the cooling water path 6, and the electric water pump 9 installed in the heat storage tank 8. A cooling water circulation path 12 is formed.

  Here, the structure around the cylinder head 2 and the cylinder block 4 will be described in detail.

  A cylinder 13 is provided in the cylinder block 4, and a piston 14 is fitted in the cylinder 13. When the piston 14 moves up and down in the cylinder 13, the output shaft (not shown) of the internal combustion engine is rotated. The combustion chamber 15 is a space defined by the cylinder head 2, the cylinder block 4, and the piston 14. The combustion chamber 15 communicates with an intake port 18 and an exhaust port 19 via an intake valve 16 and an exhaust valve 17, respectively. During operation of the internal combustion engine, introduction of an air-fuel mixture through the intake port 18 or through the exhaust port 19 is performed. Exhaust gas is discharged. A fuel injection valve 20 attached to the intake port 18 injects and supplies fuel based on a command signal from an electronic control unit (ECU) 21. The fuel injected and supplied by the fuel injection valve 20 is atomized in the intake port 18. As shown in FIG. 1, the intake port 18 communicates with an intake duct 23 that configures the inside of an inner tube 22 having a double tube structure as a passage for intake air. Further, an air cleaner 24 for removing impurities from the intake air is communicated upstream of the intake duct 23. Impurities are removed by the air cleaner 24, and then the intake air that has passed through the inner pipe 22 of the intake duct 23 is taken into the combustion chamber 15 while forming an air-fuel mixture with the fuel atomized in the intake port 18. An igniter 25 that is driven based on a command signal from an electronic control unit (ECU) 21 energizes the spark plug 26 at an appropriate timing, so that the air-fuel mixture taken into the combustion chamber 15 is combusted.

  In the cylinder head 2, an intake port side cooling water passage 3a and an exhaust port side cooling water passage 3b corresponding to a part of the cylinder head side cooling water passage 3 are formed in the vicinity of the intake port 18 and the exhaust port 19, respectively. Has been. On the other hand, the cylinder block side cooling water passage 5 is formed so as to surround the outer periphery of the cylinder 13.

  Next, the structure of the heat storage tank 8 installed in the cooling water circuit 12 of FIG. 1 will be described.

  For example, as shown in FIG. 1, the heat storage tank 8 is provided between the resin forming the outer pipe 27 of the intake duct 23 having a double pipe structure and the inner pipe 22. The resin forming the outer tube 27 is a resin having air tightness and liquid tightness and having a predetermined heat insulating property. Therefore, even if the amount of heat released from the surface of the internal combustion engine main body 1 to the surrounding space increases, the intake duct 23 blocks heat transferred from the surrounding space due to the heat insulation of the resin forming the outer pipe 27. be able to. Therefore, it is possible to suppress a decrease in filling efficiency due to excessive heating of the intake air fed to the combustion chamber 15. Further, when the heat storage tank 8 is provided between the internal combustion engine body 1 and the intake duct 23, a space existing between the internal combustion engine body 1 and the intake duct 23 is reduced by an area occupied by the heat storage tank 8. Become. In this embodiment, the heat storage tank 8 is provided between the inner pipe 22 and the resin that forms the outer pipe 27 of the intake duct 23 having a double pipe structure, so that the internal combustion engine body 1 and the intake duct 23 are separated. Since the area occupied by the heat storage tank 8 in the space between them can be reduced, the space between the internal combustion engine body 1 and the intake duct 23 can be increased.

  In the heat storage tank 8 shown in FIG. 1, the storage portion is composed of an outer tube 27 and an inner tube 22, and has a hollow column shape. The storage portion of the heat storage tank 8 in the present embodiment has a length equivalent to that of the intake duct 23, and the intake duct 23 is excessively caused by the heat released from the surface of the internal combustion engine body 1 to the surrounding space. It can suppress reliably that it is heated.

  For example, a silica-based ultrafine porous material is used as the resin material forming the outer tube 27 according to the present embodiment. The silica-based ultrafine porous material is obtained by molding ultrafine particulate silica as a main component, blending a fine powdery inorganic fibrous filler and an infrared shielding material, and press-molding it.

  The shape of the intake duct 23 having a double-pipe structure is, for example, a hollow column as shown in FIG. As described above, the outer tube 27 having a double-pipe structure is formed of a resin having air tightness, liquid tightness, and predetermined heat insulation properties. Thereby, the heat storage tank 8 can store a predetermined amount of cooling water in a state of being thermally insulated from the outside. The cooling water path 6 and the inlet 10 of the heat storage tank 8 and the outlet 11 of the heat storage tank 8 and the cooling water path 7 are connected to each other, and the electric water pump 9 installed in the middle of the cooling water path 6 is operated. Thus, inflow of cooling water into the heat storage tank 8 and outflow of cooling water from the heat storage tank 8 are possible.

  The inlet 10 installed in the heat storage tank 8 is provided toward the circumferential direction of the heat storage tank 8, for example, as shown in FIG. The circumferential direction is attached with angles α and β with respect to the axis (A) of the heat storage tank 8 and the normal (B) at the installation location of the inlet. In the present embodiment, these angles α and β are both right angles. When the inlet 10 is provided in parallel with the axis (A) of the heat storage tank 8, the flow of cooling water flowing from the inlet 10 into the heat storage tank 8 does not have a circumferential component of the heat storage tank 8. Therefore, it is not possible to give a flow to the cooling water stored on the side opposite to the installation location of the inlet 10 across the intake duct 23. Further, when the inlet 10 is provided in parallel with the normal line (B) at the installation location, the cooling water flowing into the heat storage tank 8 from the inlet 10 becomes the inner pipe 22 of the intake duct 23 having a double pipe structure. The flow rate of the cooling water is reduced by colliding with. Therefore, the flow of the cooling water from the inlet 10 toward the outlet 11 becomes small, and the cooling water stored in the heat storage tank 8 is stagnated. In the present embodiment, since the inlet 10 is attached as described above, the cooling water flowing into the heat storage tank 8 has a certain flow velocity and a circumferential flow, so that the entire cooling water in the heat storage tank 8 has a circumferential direction. Can be given. That is, since the stagnation of the high-temperature cooling water stored in the heat storage tank 8 can be eliminated, it is possible to suppress the high-temperature cooling water (hot water) from remaining in the heat storage tank 8 and to warm up the internal combustion engine. Sometimes hot coolant can be supplied to the internal combustion engine body 1.

  Next, an outline of the heat storage device for the internal combustion engine according to the present embodiment will be described with reference to FIG. FIG. 3 is a diagram schematically showing the flow path of the cooling water in the heat storage device of the internal combustion engine shown in FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The electric water pump 9 is an electric pump driven by a motor (not shown) mounted on the vehicle. This motor is driven and controlled by a command signal from an electronic control unit (ECU) 21. In addition, a radiator side bypass passage 30 for air-cooling the cooling water via the radiator 29 is communicated with the cooling water passage 6. The radiator side bypass passage 30 is connected to a heater core side bypass passage 32 through which cooling water passes through a heater core 31 for heating the vehicle interior. The mechanical water pump 33 uses a driving force transmitted from an output shaft (not shown) of the internal combustion engine, and the cylinder block side cooling water passage from the radiator side bypass passage 30 and the heater core side bypass passage 32 during operation of the internal combustion engine. The cooling water is drawn into 5. When the mechanical water pump 33 is activated along with the operation of the internal combustion engine, the cooling water in the radiator side bypass passage 30 and the heater core side bypass passage 32 is urged to generate a flow in the direction of the arrow.

  Furthermore, the radiator 29 provided in the radiator side bypass passage 30 radiates the heat of the heated cooling water to the outside. The electric fan 29 a is driven based on a command signal from the electronic control unit (ECU) 21, and enhances the heat dissipation action of the cooling water by the radiator 29. A thermo valve 34 is provided in the middle of the radiator-side bypass passage 30 and downstream of the radiator 29. The thermo valve 34 is a well-known control valve that opens and closes in response to the temperature, and opens when the coolant temperature in the radiator bypass passage 30 near the thermo valve 34 exceeds a predetermined temperature (for example, 80 ° C.). Then, the flow of the cooling water is allowed, and when the temperature falls below the predetermined temperature (for example, 80 ° C.), the valve is closed to restrict the flow of the cooling water.

  That is, when the temperature of the cooling water exceeds 80 ° C. during operation of the internal combustion engine, the thermo valve 34 is opened, the flow of the cooling water in the radiator side bypass passage 30 is allowed, and the cooling water is forcibly cooled by the action of the radiator 29. Is done. Here, for the internal combustion engine, a state where the temperature of the cooling water (approximately the same as the cooling water temperature in the cooling water passage 4) is higher than 80 ° C. is called a warm state, and a state where the temperature is 80 ° C. or lower is called a cold state. I will decide.

  The heater core 31 for heating the vehicle interior provided in the heater core side bypass passage 32 uses the heat of the cooling water heated in the internal combustion engine to heat the vehicle interior (not shown) as necessary. The electric fan 31a driven based on a command signal from the electronic control unit (ECU) 21 urges heat radiation of the cooling water passing through the heater core 31 for heating the vehicle interior, and warms air generated by the heat radiation of the cooling water to the air passage (see FIG. (Not shown).

  The check valves 28 a and 28 b provided in the middle of the cooling water path 6 and the cooling water path 7 allow only the flow of cooling water from the cooling water path 6 to the cooling water path 7 via the heat storage tank 8. To prevent backflow.

  A cooling water circulation path constituted by the cooling water circulation path 12, the cylinder block side cooling water path 5, the radiator side bypass path 30, and the heater core side bypass path 32 is referred to as a cooling system 35.

  Next, referring to FIG. 4 to FIG. 6, an outline of the behavior of the cooling water executed by the heat storage device for the internal combustion engine according to the embodiment of the present invention through a command signal of the electronic control unit (ECU) 21 will be described. explain. 4 to 6, the same components as those in FIGS. 1, 2, and 3 are denoted by the same reference numerals, and detailed description thereof is omitted. In addition, the behavior of the cooling water in the heat storage device of the internal combustion engine is different from the execution timing and execution conditions because of “pre-engine start (preheat)”, “cold after engine start”, and “warm after engine start”. It is roughly divided into “time”.

  4, 5, and 6 explain how the flow of the cooling water circulating through the cooling system of the heat storage device of the internal combustion engine shown in FIG. 1 changes according to the operating state and temperature state of the internal combustion engine. FIG. 2 is a schematic diagram schematically showing a heat storage device of the internal combustion engine. 4, 5, and 6, a passage in which the flow of cooling water is generated is indicated by a solid line, and a passage in which little or no flow of cooling water is generated is indicated by an alternate long and short dash line.

  First, FIG. 4 shows a heat storage device for an internal combustion engine when the internal combustion engine is in a stopped state and the electric water pump 9 is in an operating state. When the electric water pump 9 operates, the cooling water flows along the cooling water circulation path 12. At this time, since the internal combustion engine is in a stopped state, the mechanical water pump 33 driven by the crankshaft (not shown) of the internal combustion engine is not operating. The state of the cooling system 35 shown in FIG. 4 corresponds to that immediately before the internal combustion engine starts the engine, and is embodied by “preheat control”.

  Next, the content and execution procedure of “preheat control” will be described in more detail. The internal combustion engine is in a warm state (cooling water temperature is generally higher than 80 ° C.) immediately before the end of the previous engine operation (engine stop), and high-temperature cooling water is contained in the heat storage tank 8. Assume that it is stored.

  First, in order to ensure a period for performing preheating before starting the internal combustion engine, events that occur inevitably prior to the start of the internal combustion engine, such as door opening / closing, seating, seat belt mounting, door lock opening, brake pedal Are determined by the electronic control unit (ECU) 21. As shown in FIG. 4, a door opening / closing sensor 36, a seating sensor 37, a seat belt sensor 38, a door lock sensor 39, a brake sensor 40, a shift position sensor 41, and an ignition switch 42 are connected to an electronic control unit (ECU) 21. Yes. The electronic control unit (ECU) 21 determines whether or not the internal combustion engine has been started based on signals from these sensors and the like. When the electronic control unit (ECU) 21 determines that the internal combustion engine is not yet started, the electric water pump 9 is operated to supply the hot water in the heat storage tank 8 to the cylinder head side cooling water passage 3 via the cooling water passage 7. To do. Here, the temperature of the cylinder head 2 reaches a temperature (60 ° C. to 80 ° C.) equivalent to the high-temperature coolant temperature in the heat storage tank 8 in about 5 to 10 seconds from the start of the operation of the electric water pump 9. Therefore, it is preferable that, for example, about 10 seconds elapse after the start of the operation of the electric water pump 9, and the internal water engine is started after the electric water pump 9 is stopped. As a result, the engine of the internal combustion engine can be started after the temperature of the cylinder head 2 has reliably reached a temperature (60 ° C. to 80 ° C.) equivalent to the high-temperature cooling water temperature in the heat storage tank 8.

  5 and 6 each show a heat storage device for an internal combustion engine when the internal combustion engine is in an operating state. However, FIG. 5 shows a state in which the cooling water temperature in the vicinity of the thermo valve 34 is 80 ° C. or less in the cooling system 35, and FIG. 6 shows that the cooling water temperature in the vicinity of the thermo valve 34 in the cooling system 35 is 80 ° C. It is in a state of exceeding.

  As shown in FIGS. 5 and 6, when the mechanical water pump 33 is in an operating state and the electric water pump 9 is in a stopped state as the internal combustion engine is operating, the cylinder head side cooling water passage 3 and the cylinder Except for the common cooling water passage 3c which is a part of the cooling water circulation passage 12 from the communication portion with the block side cooling water passage 5 to the connection portion 43 of the radiator side bypass passage 30 in the cooling water passage 6, the cooling water circulation passage 12 is provided. The flow of the cooling water along is almost stopped.

  As shown in FIG. 5, if the cooling water temperature in the vicinity of the thermo valve 34 in the cooling system is 80 ° C. or less, the thermo valve 34 is closed, and the flow of the cooling water from the radiator 29 toward the thermo valve 34 is restricted. The Therefore, the cooling water is caused to flow through the cylinder block side cooling water passage 5, the common cooling water passage 3 c that is a part of the cooling water circulation passage 12, and the heater core side bypass passage 32 by the action of the mechanical water pump 33. Become. (Fig. 5)

  On the other hand, when the cooling water temperature in the vicinity of the thermo valve 34 in the cooling system 35 exceeds 80 ° C., the thermo valve (control valve) 34 is opened, and the flow of the cooling water from the radiator 29 to the thermo valve 34 is allowed. The Accordingly, the cooling water is supplied into the cylinder block side cooling water passage 5, the common cooling water passage 3 c that is a part of the cooling water circulation passage 12, the heater core side bypass passage 32, and the radiator side bypass passage 30 by the action of the mechanical water pump 33. Will be fluidized. (Fig. 6)

  5 and 6, after the “preheat control” is performed, the cooling water passage from the cooling water passage space other than the cooling water circulation passage 12 is cooled by the operation of the mechanical water pump 33 so that the low-temperature cooling water is supplied to the cylinder head side cooling water passage. 3 flows into. For this reason, the temperature of the cylinder head 2 temporarily drops slightly. However, the temperature of the cylinder head 2 gradually rises due to the heat generation action of the internal combustion engine body 1 itself accompanying the operation of the internal combustion engine, and about a few seconds have elapsed since the engine start of the internal combustion engine, depending on environmental conditions such as the outside air temperature. After that, when the temperature of the cylinder head 2 (approximately the same as the cooling water temperature) reaches 80 ° C., the thermo valve 34 repeats opening and closing in the vicinity of the temperature, whereby the cooling water temperature (temperature of the cylinder head 2) is It is maintained at a substantially constant temperature (80 ° C.).

  Further, with the end of the engine operation of the internal combustion engine (engine stop), the electronic control unit (ECU) 21 operates the electric water pump 9 and the cooling water temperature is maintained at a substantially constant temperature (80 ° C.) in the heat storage tank 8. Stores cooling water (hot water). That is, the heat energy held by the high-temperature cooling water is stored in the heat storage tank 8.

  Note that the cooling system 35 during the engine operation of the internal combustion engine in the present embodiment basically holds the state shown in FIG. 5 or FIG.

  In the present embodiment, the heat storage tank 8 shown in FIG. 1 is adopted. However, for example, heat storage tanks 44, 47, and 50 as shown in FIGS. 7, 8, and 9 may be used. 7, 8, and 9, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the heat storage device for an internal combustion engine shown in FIG. 7, a part of the intake duct 45 has a double-pipe structure, and both ends have a single-pipe structure. The heat storage tank 44 is provided between the outer tube 46 and the inner tube 22 in a portion of the intake duct 45 having a double tube structure. Therefore, since the space required for mounting the heat storage tank 44 can be reduced, superiority can be exhibited in terms of mountability of the heat storage tank 44 with respect to vehicle mounting.

  Similarly, in the heat storage tank 47 shown in FIG. 8, both the outer pipe 27 and the inner pipe 49 of the intake duct 48 are formed of a resin having air tightness and liquid tightness and having predetermined heat insulation properties. Therefore, since the heat of the high-temperature cooling water stored in the heat storage tank 47 can be suppressed from transferring to the intake air passing through the inner pipe 49, the intake air in the intake duct 48 is heated excessively. Can be suppressed. Therefore, it is possible to reliably suppress a decrease in charging efficiency in the combustion chamber of the internal combustion engine.

  Similarly, FIG. 9 shows only the intake duct 51 and the heat storage tank 50 in the heat storage device of the internal combustion engine. The intake duct 51 shown in FIG. 9 has a single-pipe structure, and the heat storage tank 50 is integrally provided on the intake duct 51 on the internal combustion engine body 1 side. Further, the outer wall 52 of the intake duct 51 is formed by the resin forming the outer wall of the heat storage tank 50 having a hollow column shape. Therefore, it is possible to prevent the intake air in the intake duct 51 from being heated excessively due to the heat insulation of the resin that forms the outside of the heat storage tank 50. In addition, it is not necessary to set conditions in particular about installation of the inflow port 10 and the outflow port 11 which are provided in the heat storage tank 50 shown in FIG.

  Moreover, in this Embodiment, the modification of the shape of the intake duct 23 which is the double pipe structure shown in FIG. 2 is shown in FIG. 10, FIG. 10 and 11, the same components as those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted. The intake duct 53 shown in FIG. 10 has a quadrangular prism shape, and the intake duct 54 shown in FIG. 11 has a triangular prism shape. Obviously, various shapes of intake ducts 53 and 54 may be used.

  It is obvious that the double-pipe intake ducts 23, 53, and 54 shown in FIGS. 2, 10, and 11 may have a multi-pipe structure such as a triple-pipe structure.

  In the present embodiment, for example, a heat storage device for an internal combustion engine as shown in FIG. 12 may be used instead of the cooling water circulation path 12 shown in FIG. In this internal combustion engine heat storage device, as a part of the cooling system 55, the cylinder head side cooling water passage 3, the heater core side bypass passage 32, the heater core 31, the heater core side bypass passage 32, the mechanical water pump 33, the cylinder block side cooling. A cooling water circulation path 56 for circulating cooling water in the order of the water passage 5 is provided. The heat storage tank 8 is arranged in parallel to the cooling water circulation path 56 via the cooling water path 6 and the cooling water path 7. In the heat storage device for an internal combustion engine having such a configuration, when the electric water pump 9 installed in the middle of the cooling water passage 6 is operated, the cooling water is boosted by the electric water pump 9 and further downstream of the electric water pump 9. It is sent to the cooling water passage 6 and reaches the heat storage tank 8. On the other hand, during engine operation of the internal combustion engine, the electric water pump 9 is stopped and the mechanical water pump 33 is activated.

  That is, during the preheating, the electric water pump 9 is operated, so that the cooling water flows in the direction of the arrow X in each part, and the mechanical water pump 33 operates to draw the cooling water into the internal combustion engine body 1 during normal operation. As a result, the cooling water flows in the direction of the arrow Y at each part. Therefore, the cooling water in the cooling system flows in the opposite direction during preheating and during normal engine operation.

  Further, a flow rate control valve 57 for adjusting the flow rate of the cooling water flowing from the cylinder head side cooling water passage 3 to the heater core side bypass passage is provided. When the mechanical water pump 33 is driven with the flow control valve 57 fully closed, the cooling water circulates in a state of being generally confined in the internal combustion engine body 1 (direction Z). According to such an embodiment, the region in which the cooling water circulates can be kept small immediately after the internal combustion engine is started, so that the cooling water temperature in the internal combustion engine body 1 can be rapidly warmed up. Further, when the above-mentioned “preheat control” is used in combination, the warm-up efficiency before and after the start of the internal combustion engine can be further increased.

  In the heat storage device for an internal combustion engine according to the embodiment, the fuel injected and supplied by the fuel injection valve 20 is atomized in the intake port 18 and passes through the inner pipe 22 of the intake duct 23 having a double pipe structure. As described with reference to FIG. 1, the air-fuel mixture is taken into the combustion chamber 15 and used for combustion while forming an air-fuel mixture with the intake air. From the viewpoint of quickly atomizing the fuel supplied by the injection in the intake port 18 or preferably maintaining the atomized state, the intake air formed in the internal combustion engine body 1, particularly the cylinder head 2. The temperature of the inner wall of the port 18 is preferably higher than a predetermined temperature (60 ° C., preferably about 80 ° C.). This is because when the temperature of the inner wall of the intake port 18 is lowered, it is difficult to atomize the fuel efficiently or to easily attach the atomized fuel and to keep the atomized state. Such deterioration of fuel atomization makes it difficult to optimize the combustion efficiency and air-fuel ratio, and causes a decrease in exhaust characteristics and fuel consumption.

  Therefore, the internal combustion engine main body 1 is configured so that cooling water can be circulated for each part such as a part around the intake port 18 of the cylinder head 2, a part around the exhaust port 19 of the cylinder head 2, and the cylinder block 4. Keep it. Then, in order to improve the exhaust characteristics and fuel consumption at the initial start of the internal combustion engine, a priority order for increasing the temperature may be set, and control may be performed so that hot water is supplied sequentially from a part with a higher priority order.

  Specifically, first, a part of the total amount of hot water stored in the heat storage tank 8 is supplied to the vicinity of the intake port 18 and then stored in the heat storage tank 8 in the vicinity of the exhaust port 19 after a predetermined period. It is preferable to supply another part of the total amount of hot water, and then supply the remainder of the hot water stored in the heat storage tank 8 to the cylinder block 4 after a predetermined period. In addition, priority is given to a range in which hot water is supplied, such as hot water supply to a portion around the intake port 18 → hot water supply to a portion including the vicinity of the intake port 18 and the exhaust port 19 → hot water supply to the entire internal combustion engine. The structure of the cooling system 35 and the control logic for performing preheating may be constructed so as to sequentially expand from a local range with a high order to a wide range including a part with a low priority.

  In the present embodiment, the cooling system 35 and the electronic control unit (ECU) 21 configured integrally with the internal combustion engine constitute the heat storage device in the present embodiment. On the other hand, heat may be stored through a heat medium such as oil instead of cooling water as the heat medium.

  Further, such an internal combustion engine may be a so-called hybrid engine that is further provided with other driving means (for example, an electric motor) and generates a driving force in cooperation with the internal combustion engine and the other driving means (prime motor). Good. In this case, for example, control may be performed such that the driving operation is performed only by other driving means until the heat supply (preheating) from the heat storage tank 8 is completed.

  Further, instead of the “preheat control” according to the present embodiment, the cooling water (hot water) stored in the heat storage tank 8 at a temperature of approximately 80 ° C. or higher is used at the same time as the engine start of the internal combustion engine. It may be supplied to the passage 3. In this case, the temperature of the cylinder head 2 (approximately the same as the cooling water temperature) reaches 80 ° C. after about 10 seconds have passed since the engine start of the internal combustion engine, and then the cooling water temperature (the temperature of the cylinder head 2) is substantially constant ( 80 ° C.). Therefore, as the internal combustion engine starts, the internal combustion engine body 1 can be warmed up earlier than when the temperature of the cylinder head 2 gradually rises only by the heating action of the internal combustion engine body 1 itself. Performance and exhaust emission can be improved.

  Further, in the heat storage tank 8 according to the present embodiment, for example, as shown in FIG. 13, a spiral rectifying plate 58 may be installed on the outer peripheral surface of the inner tube 22 of the intake duct 23. In this case, the flow of the cooling water in the heat storage tank 8 that has flowed in from the inlet 10 attached in the circumferential direction of the heat storage tank 8 is a flow in which the circumferential component is further increased with respect to the axial direction of the heat storage tank 8. It becomes. Therefore, the high temperature cooling water stored in the heat storage tank 8 is sequentially pushed out toward the outlet 11 by the cooling water flowing into the heat storage tank 8 from the inlet 10 and flows into the heat storage tank 8 from the inlet 10. The low-temperature cooling water reaches the vicinity of the outlet 11 before the high-temperature cooling water (hot water) remaining in the heat storage tank 8, and the low-temperature cooling water enters the internal combustion engine body 1 during the warm-up operation of the internal combustion engine. Supplying can be further suppressed. Furthermore, the temperature drop of the warm water by mixing with the low temperature cooling water which flows in from the inflow port 10 and the high temperature cooling water (hot water) stored in the heat storage tank 8 can also be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a partially enlarged cross-sectional structure around a combustion chamber and around an intake pipe of an internal combustion engine according to an embodiment of the present invention. The schematic diagram which expands and shows the structure of the air intake duct concerning the embodiment. The schematic block diagram which shows the thermal storage apparatus of the internal combustion engine concerning the embodiment. The schematic diagram which shows schematically the thermal storage apparatus of the internal combustion engine concerning the embodiment. The schematic diagram which shows schematically the thermal storage apparatus of the internal combustion engine concerning the embodiment. The schematic diagram which shows schematically the thermal storage apparatus of the internal combustion engine concerning the embodiment. The schematic diagram which expands partially the cross-sectional structure of the combustion chamber periphery and the intake pipe periphery periphery about the internal combustion engine concerning other embodiment. The schematic diagram which expands partially the cross-sectional structure of the combustion chamber periphery and the intake pipe periphery periphery about the internal combustion engine concerning other embodiment. The schematic diagram which expands partially the cross-sectional structure of the combustion chamber periphery and the intake pipe periphery periphery about the internal combustion engine concerning other embodiment. The schematic block diagram which shows the structure of the intake duct concerning other embodiment. The schematic block diagram which shows the structure of the intake duct concerning other embodiment. The schematic diagram which shows schematically the thermal storage apparatus of the internal combustion engine concerning other embodiment. The schematic diagram which expands and shows the structure of the thermal storage tank concerning other embodiment.

Explanation of symbols

1 Internal combustion engine body 2 Cylinder head 3 Cylinder head side cooling water passage 3a Intake port side cooling water passage 3b Exhaust port side cooling water passage 3c Common cooling water passage 4 Cylinder block 5 Cylinder block side cooling water passage 6 Cooling water passage 7 Cooling water Path 8 Heat storage tank 9 Electric water pump 10 Inlet 11 Outlet 12 Cooling water circulation path 13 Cylinder 14 Piston 15 Combustion chamber 16 Intake valve 17 Exhaust valve 18 Intake port 19 Exhaust port 20 Fuel injection valve 21 Electronic control unit (ECU)
22 Inner pipe 23 Intake duct 24 Air cleaner 25 Igniter 26 Spark plug 27 Outer pipe 28a Check valve 28b Check valve 29 Radiator 29a Electric fan 30 Radiator side bypass passage 31 Heater core 31a Electric fan 32 Heater core side bypass passage 33 Mechanical water pump 34 Thermo valve 35 Cooling system 36 Door open / close sensor 37 Seat sensor 38 Seat belt sensor 39 Door lock sensor 40 Brake sensor 41 Shift position sensor 42 Ignition switch 43 Connection 44 Thermal storage tank 45 Intake duct 46 Outer pipe 47 Thermal storage tank 48 Intake duct 49 Inside Pipe 50 Thermal storage tank 51 Intake duct 52 Outer wall 53 Intake duct 54 Intake duct 55 Cooling system 56 Cooling water circulation path 57 Flow control valve 58 Rectifier plate

Claims (5)

In a heat storage device for an internal combustion engine comprising an intake passage of the internal combustion engine and a heat storage tank for storing a heat medium, covering at least a part of the entire circumference in the longitudinal direction of the intake passage with a heat insulating material of the heat storage tank. A heat storage device for an internal combustion engine. 2. The heat storage device for an internal combustion engine according to claim 1, wherein an entire circumference of at least a part of the intake passage is covered with a storage portion of the heat storage tank. The heat storage device for an internal combustion engine according to claim 1, wherein the intake passage is an intake duct that communicates an air cleaner and a surge tank. The heat storage device for an internal combustion engine according to claim 2 or 3, wherein an inlet of the heat storage tank is provided toward a circumferential direction of the heat storage tank. 5. The heat storage device for an internal combustion engine according to claim 1, wherein at least a part of the heat storage tank or at least a part of the intake passage is formed of resin.

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