JP2016191343A - engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress increase of the amount of moisture causing dew condensation on an injection hole portion of a fuel injection valve after stopping an engine.SOLUTION: An engine 10 includes a cylinder block 12 having a cylinder 24, a cylinder head 18 disposed on a top part of the cylinder 24, a piston 14 disposed movably in the cylinder 24, a fuel injection valve 28 disposed on the cylinder head 18, and injecting a fuel into the cylinder 24, a heater 34 disposed around an injection hole portion 32 of a tip of the fuel injection valve 28 in the cylinder head 18, and an ECU 200 operating the heater 34 during the operation of the engine 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for suppressing condensation at the tip of a fuel injection valve exposed in a cylinder in a direct injection engine having a fuel injection valve that directly injects fuel into the cylinder.

  2. Description of the Related Art Conventionally, in a direct injection engine having a fuel injection valve that directly injects fuel into a combustion chamber in a cylinder, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2007-303419 (Patent Document 1), A configuration in which a rod-like in-cylinder fuel injection valve is inserted into the circular hole is known.

  Further, in such a direct injection engine, generally, reduction of nitrogen oxide (NOx) and improvement of fuel consumption can be achieved by using a reduction in compression ratio or EGR (Exhaust Gas Recirculation).

JP 2007-303419 A

  However, in such a direct-injection engine, the nozzle hole at the tip of the fuel injection valve is exposed in the cylinder. Therefore, if the engine is left for a certain period of time after the engine is stopped, the moisture in the air in the cylinder is condensed. May adhere to the nozzle hole. In particular, in an engine equipped with EGR, exhaust gas containing moisture generated by combustion is recirculated to the intake side, so that the amount of moisture in the cylinder may be larger than when EGR is not installed. is there. Further, by reducing the compression ratio, the temperature in the cylinder may be lower than when the compression ratio is high, and the temperature of the components in the cylinder (including the injection hole portion of the fuel injection valve) may be lowered. As a result, after the engine is stopped, more water may adhere to the injection hole portion of the fuel injection valve due to condensation. When moisture adheres to the nozzle hole, it may cause deterioration.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an engine that suppresses an increase in the amount of moisture condensed in the nozzle hole portion of the fuel injection valve after the engine is stopped. It is.

  An engine according to an aspect of the present invention includes a cylinder block having a cylinder, a cylinder head provided at the top of the cylinder, a piston provided movably in the cylinder, a cylinder head, and fuel in the cylinder. A fuel injection valve that injects, a heater that is provided in the cylinder head and around the injection hole at the tip of the fuel injection valve, and a control device that operates the heater during operation of the engine.

  If it does in this way, the fall of the temperature of the nozzle hole part of the front-end | tip of a fuel injection valve can be suppressed or temperature can be raised by operating a heater during operation of an engine. Therefore, even if the temperature of the nozzle hole is lowered after the engine is stopped, the time until the temperature falls below the dew point is longer than when the heater is not operated. As a result, dew condensation is promoted at a location different from the nozzle hole part, so that an increase in the amount of moisture condensed at the nozzle hole part can be suppressed.

  Preferably, the tip of the fuel injection valve has a cylindrical shape. A heater is provided in the position which opposes the outer peripheral side surface of a front-end | tip.

  If it does in this way, the fall of the temperature of a nozzle hole part can be suppressed or the temperature can be raised during operation | movement of an engine with the heater provided in the outer periphery of a nozzle hole part.

More preferably, the heater is provided at a position facing the outer peripheral side surface on the intake valve side.
In this way, the temperature on the intake valve side tends to be lower than that on the exhaust valve side on the outer peripheral side surface of the tip. For this reason, by providing the heater at a position facing the outer peripheral side surface on the intake valve side, it is possible to suppress or increase the temperature of the nozzle hole during operation of the engine.

  More preferably, the control device operates the heater when the engine coolant temperature is lower than a threshold during operation of the engine.

  If it does in this way, since the temperature of a nozzle hole part can be raised rapidly, even when an engine stops, the increase in the moisture content which dew condensation in a nozzle hole part can be suppressed.

  More preferably, the control device calculates an estimated value of the amount of condensed water generated by condensation based on the operating state of the engine during operation of the engine, and the calculated estimated value is greater than a threshold value. If so, activate the heater.

  In this way, the heater can be operated when an increase in the amount of moisture condensed in the nozzle hole is predicted in the cylinder. Therefore, when the engine is stopped, the amount of moisture condensed in the nozzle hole can be reliably ensured. Increase can be suppressed.

  According to this invention, by operating the heater during the operation of the engine, it is possible to suppress or increase the temperature of the nozzle hole at the tip of the fuel injection valve. Therefore, even if the temperature of the nozzle hole is lowered after the engine is stopped, the time until the temperature falls below the dew point is longer than when the heater is not operated. As a result, dew condensation is promoted at a location different from the nozzle hole part, so that an increase in the amount of moisture condensed at the nozzle hole part can be suppressed. Therefore, it is possible to provide an engine that suppresses an increase in the amount of moisture that condenses in the nozzle hole of the fuel injection valve after the engine is stopped.

It is a figure which shows schematic structure of an engine. It is a figure for demonstrating the structure of the EGR system provided in an engine. It is a functional block diagram of ECU. It is a flowchart which shows the control processing performed by ECU. It is a timing chart for demonstrating operation | movement of ECU.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  FIG. 1 shows a schematic configuration of the engine 10. In the present embodiment, engine 10 is an internal combustion engine having a fuel injection valve that injects fuel directly into a combustion chamber. The engine 10 will be described using a diesel engine as an example, but may be a gasoline engine or a gas engine.

  As shown in FIG. 1, the engine 10 includes a cylinder block 12, a piston 14, a cylinder head 18, an intake valve 22, an exhaust valve 26, a fuel injection valve 28, and a heater 34. In FIG. 1, arrows indicate the flow of intake air and the flow of exhaust gas when the engine is operating.

  The cylinder block 12 is provided with one or more circular holes as cylinders 24 with the vertical direction of the paper surface of FIG. The piston 14 is accommodated in the cylinder 24. The piston 14 is connected to a crankshaft (not shown) by a connecting rod 15. As the piston 14 reciprocates, the reciprocating motion is changed to a rotational motion by the connecting rod 15 and the crankshaft rotates. A ring groove is provided on the outer periphery of the piston 14, and a plurality of (for example, three) piston rings 16 are fitted into the ring groove.

  The cylinder head 18 has one end connected to the intake manifold (see FIG. 2), the other end connected to the cylinder 24 of the cylinder block 12, and one end connected to the exhaust manifold (see FIG. 2). As a result, an exhaust port 30 whose other end is connected to the cylinder 24 of the cylinder block 12 is formed.

  The intake port 20 takes in air from an intake port (not shown) and distributes air flowing through the intake manifold to the cylinder 24. An intake valve 22 is provided at a connection portion between the intake port 20 and the cylinder 24. The intake valve 22 basically operates in synchronization with the rotation of the crankshaft, and communicates between the intake port 20 and the cylinder 24 or blocks communication.

  The exhaust port 30 circulates the gas exhausted from the cylinder 24 to the exhaust manifold. An exhaust valve 26 is provided at a connection portion between the exhaust port 30 and the cylinder 24. As with the intake valve 22, the exhaust valve 26 basically operates in synchronization with the rotation of the crankshaft, and communicates between the exhaust port 30 and the cylinder 24 or blocks communication.

  The cylinder head 18 is provided with a fuel injection valve 28 at a central portion when the cylinder is viewed from the central axis direction. The fuel injection valve 28 is connected to a common rail (not shown), and high-pressure fuel stored in the common rail is supplied to the fuel injection valve. The fuel injection valve 28 is operated by a control signal from the ECU 200 and supplies fuel to the combustion chamber in the cylinder 24. The fuel injection valve 28 has a cylindrical shape and is provided by being inserted into a circular hole formed in the cylinder head 18. A nozzle hole 32 through which fuel is injected is provided at the tip of the fuel injection valve 28 so as to be exposed in the cylinder 24.

  The heater 34 is disposed around the nozzle hole portion 32 provided in the cylinder head 18 (that is, around the tip of the fuel injection valve 28). The heater 34 is an electric heater configured using, for example, a heating wire, and the switch operation of the heater 34 is controlled by the ECU 200. That is, the switch of heater 34 operates in one of an on state and an off state in response to receiving control signal HT from ECU 200. In the present embodiment, the heater 34 is provided so as to surround the periphery of the injection hole portion 32.

  The ECU 200 includes a ROM (Read Only Memory) that stores programs and data, a CPU (Central Processing Unit) that performs various processes, a RAM (Random Access Memory) that stores processing results of the CPU, and external information. Includes an input port and an output port for communication. Various sensors are connected to the input port.

  ECU 200 receives signals from devices such as various sensors (for example, water temperature sensor 300) connected to the input port, and various devices (for example, fuel injection valve 28 and heater) connected to the output port based on the received signals. 34) etc. are controlled.

  Various sensors connected to the input port include a coolant temperature sensor 300 for detecting a coolant temperature Tw (hereinafter referred to as water temperature) Tw of the engine 10 and a rotational speed of the crankshaft of the engine 10 (hereinafter referred to as engine rotational speed). A rotation speed sensor 302 for detecting NE and an intake air temperature sensor 304 for detecting the temperature of intake air temperature (hereinafter referred to as intake air temperature) Ti flowing from the intake port to the intake port 20.

  The water temperature sensor 300 outputs a signal indicating the detected water temperature to the ECU 200. The rotation speed sensor 302 outputs a signal indicating the detected engine rotation speed to the ECU 200. The intake air temperature sensor 304 outputs a signal indicating the detected intake air temperature to the ECU 200.

  In the direct injection engine as described above, it is generally possible to reduce nitrogen oxides and improve fuel efficiency by reducing the compression ratio and using an EGR system. For example, an engine 10 equipped with an EGR system will be described with reference to FIG.

  As shown in FIG. 2, the EGR system 46 includes an intake side EGR pipe 42, a heat exchanger 40, and an exhaust side EGR pipe 44. One end of the intake EGR pipe 42 is connected to the intake manifold 36. The intake manifold 36 is connected to one end of the intake port 20. The other end of the intake side EGR pipe 42 is connected to one end of the heat exchanger 40. The other end of the heat exchanger 40 is connected to one end of the exhaust side EGR pipe 44. The other end of the exhaust side EGR pipe 44 is connected to the exhaust manifold 38. The exhaust manifold 38 is connected to one end of the exhaust port 30.

  The EGR system 46 further includes an EGR valve (not shown) provided in any one of the intake side EGR pipe 42 and the exhaust side EGR pipe 44. The ECU 200 controls the opening degree of the EGR valve to adjust the flow rate of the exhaust gas flowing through the EGR system 46.

  In such a direct injection engine, the nozzle hole portion 32 formed at the tip of the fuel injection valve is provided exposed in the cylinder 24. Therefore, if the engine is left for a certain period after the engine is stopped, In some cases, moisture in the inside condenses and adheres to the nozzle hole portion 32. In particular, in the engine 10 equipped with the EGR system 46 as described above, the exhaust gas containing moisture generated by combustion is recirculated to the intake side, so that the moisture content in the cylinder 24 is not installed in the EGR system. There are cases where it is increased compared to the case. Further, since the temperature in the cylinder 24 is lowered by reducing the compression ratio as compared with the case where the compression ratio is high, the temperature of the components in the cylinder 24 (including the injection hole portion 32 of the fuel injection valve 28) is lowered. Will be. As a result, more water may adhere to the injection hole portion 32 after the engine 10 is stopped. When moisture condenses on the nozzle hole 32, it may cause deterioration. In addition, moisture may condense in the gap between the fuel injection valve 28 and the cylinder head 18 and may drop and adhere from the tip toward the injection hole portion 32. This can also cause deterioration.

  Therefore, in the present embodiment, the heater 200 provided in the cylinder head 18 and around the tip of the fuel injection valve 28 (including the injection hole portion 32) while the ECU 200 is operating the engine 10 is provided. It is characterized in that it operates.

  In this way, by operating the heater 34 during the operation of the engine 10, it is possible to suppress or increase the temperature of the nozzle hole 32 at the tip of the fuel injection valve 28. Therefore, even if the temperature of the nozzle hole 32 decreases after the engine 10 is stopped, the time until the temperature falls below the dew point is longer than when the heater 34 is not operated. As a result, dew condensation at a location different from the nozzle hole 32 is promoted, so that an increase in the amount of moisture that forms dew at the nozzle hole 32 and its periphery can be suppressed.

  FIG. 3 shows a functional block diagram of ECU 200 that controls the operation of engine 10 according to the present embodiment. ECU 200 includes a water temperature determination unit 202, a generation amount calculation unit 204, a generation amount determination unit 206, and a heater control unit 208. In addition, these structures may be implement | achieved by software, such as a program, and may be implement | achieved by hardware.

  The water temperature determination unit 202 determines whether or not the water temperature Tw detected by the water temperature sensor 300 is higher than the threshold value Tw (0) while the engine 10 is operating. The threshold value Tw (0) is, for example, a temperature lower than the water temperature at which it is determined that the warm-up has been completed. The threshold value Tw (0) may be a temperature lower than the temperature at which the thermostat operates, for example.

  The generation amount calculation unit 204 generates the amount of condensed water generated by condensation based on the operating state of the engine 10 when the water temperature determination unit 202 determines that the water temperature Tw is lower than the threshold value Tw (0). An estimated value A (n) is calculated.

  The generation amount calculation unit 204 calculates an estimated value A (n) of the generation amount of condensed water based on, for example, the engine rotation speed NE, the water temperature Tw, the intake air temperature Ti, and the EGR rate. The EGR rate is a value obtained by dividing the amount of exhaust gas recirculated into the cylinder by the amount of gas sucked into the cylinder.

  The generation amount calculation unit 204 uses, for example, a basic value B of the generation amount per unit time from the engine rotation speed NE using a two-dimensional map indicating the relationship between the engine rotation speed NE and the basic value of the generation amount per unit time. Is calculated. In addition, the generation amount calculation unit 204 calculates the first correction coefficient Ca from the water temperature Tw using a two-dimensional map or the like showing the relationship between the water temperature Tw and the first correction coefficient Ca. Further, the generation amount calculation unit 204 calculates the second correction coefficient Cb from the intake air temperature Ti using a two-dimensional map indicating the relationship between the intake air temperature Ti and the second correction coefficient Cb. The generation amount calculation unit 204 calculates the third correction coefficient Cc from the EGR rate using a two-dimensional map or the like indicating the relationship between the EGR rate and the third correction coefficient Cc. The generation amount calculation unit 204 multiplies the calculated basic value B of the generation amount per unit time by the first correction coefficient Ca, the second correction coefficient Cb, and the third correction coefficient Cc, thereby condensing water per unit time. The estimated value C of the generation amount is calculated. The various maps are preliminarily adapted by experiments or the like and stored in advance in a storage area such as a memory of the ECU 200.

  The generation amount calculation unit 204 calculates a value D obtained by multiplying the calculated estimated value C of the condensed water per unit time by the operating time of the engine 10 from the previous calculation to the current calculation in the previous calculation. The estimated value A (n) of the amount of condensed water produced is calculated by adding to the estimated value A (n-1) of the amount of condensed water produced.

  The generation amount determination unit 206 determines whether or not the estimated value A (n) of the condensed water generation amount calculated by the generation amount calculation unit 204 is larger than the threshold value E. The threshold value E is a threshold value for determining that there is a possibility that water of a predetermined amount or more that may cause deterioration may adhere to the nozzle hole portion 32 when condensation occurs. The threshold E of the amount of condensed water produced is adapted, for example, experimentally or designally.

  The heater control unit 208 operates the heater 34 when the generation amount determination unit 206 determines that the estimated amount A (n) of the condensed water generation amount is larger than the threshold value E. The heater controller 208 energizes the heater 34 to generate heat by turning on the switch of the heater 34. The heater control unit 208 stops the heater 34 when the generation amount determination unit 206 determines that the estimated amount A (n) of the condensed water generation amount is equal to or less than the threshold value. When the switch of the heater 34 is on, the heater control unit 208 stops energization to the heater 34 by turning it off.

  With reference to FIG. 4, a control process executed by ECU 200 mounted on engine 10 according to the present embodiment will be described.

  In step (hereinafter, step is referred to as S) 100, ECU 200 determines whether or not water temperature Tw is smaller than threshold value Tw (0). If it is determined that water temperature Tw is lower than threshold value Tw (0) (YES in S100), the process proceeds to S102. If not (NO in S100), the process proceeds to S108.

  In S102, ECU 200 calculates an estimated value A (n) of the amount of condensed water generated. Since the calculation method of the estimated value A (n) of the amount of condensed water generation is as described above, detailed description thereof will not be repeated.

  In S104, ECU 200 determines whether or not estimated value A (n) of the calculated amount of condensed water is greater than or equal to threshold value E. When it is determined that estimated value A (n) of the amount of condensed water produced is equal to or greater than threshold value E (YES in S104), the process proceeds to S106. If not (NO in S104), the process proceeds to S108.

  In S106, ECU 200 operates heater 34. In S108, ECU 200 stops heater 34. For example, ECU 200 stops heater 34 when heater 34 is operating, and maintains the stopped state of heater 34 when heater 34 is stopped.

  The operation of ECU 200 of engine 10 according to the present embodiment based on the above-described structure and flowchart will be described with reference to FIG.

  The vertical axis of the upper graph in FIG. 5 indicates the temperature of the nozzle hole 32 when the heater in the cylinder 24 is operated (solid line), the temperature of the nozzle hole 32 when the heater is not operated (thick broken line), and the cylinder head 18. The temperature (one-dot chain line) is shown. The thin broken line in the upper graph of FIG. 5 indicates the change in the dew point after time T (0).

  The vertical axis of the middle graph in FIG. 5 indicates the total amount of condensation (broken line) when the heater is not operating and the amount of condensation other than the nozzle hole 32 (solid line). The vertical axis of the lower graph in FIG. 5 indicates the total amount of condensation (broken line) and the amount of condensation other than the nozzle hole 32 (solid line) during heater operation. The horizontal axis of each graph in FIG. 5 indicates time.

  For example, it is assumed that the engine 10 is in operation and the water temperature Tw of the engine 10 is smaller than the threshold value Tw (0). If the water temperature Tw is smaller than the threshold value Tw (0) during operation of the engine 10 (YES in S100), an estimated value A (n) of the amount of condensed water generated is calculated (S102). When estimated value A (n) of the amount of condensed water calculated based on the operating state of engine 10 is equal to or greater than threshold value E (YES in S104), heater 34 is operated (S106). . When the heater 34 operates to generate heat, the temperature of the injection hole portion 32 of the fuel injection valve 28 provided in the vicinity of the heater 34 increases. Then, at time T (0), for example, when the driver turns off the IG, the engine 10 is stopped. At this time, the heater 34 is also stopped.

  Since the engine 10 is stopped, after the time T (0), the dew point decreases as the temperature in the cylinder 24 decreases as shown by the thin broken line in the upper graph of FIG. Further, since the engine 10 is stopped, the temperature of the nozzle hole portion 32 and the temperature of the cylinder head 18 both decrease with the passage of time.

  At time T (1), the temperature of the cylinder head 18 falls below the dew point, so that moisture adheres to the cylinder head 18 due to condensation.

  Here, at the time T (0) when the engine 10 is stopped, as indicated by the solid line in the upper graph of FIG. 5, when the heater 34 is operating during the operation of the engine 10 (hereinafter referred to as heater operation). The temperature of the nozzle hole portion 32 in FIG. 5 is shown when the heater 34 is not operating during the operation of the engine 10 as shown by the thick broken line in the upper graph of FIG. It becomes higher than the temperature of the nozzle hole part 32.

  Therefore, when the heater is not operated, the temperature of the nozzle hole portion 32 is lower than the dew point after the time T (2), whereas when the heater is operated, the time after the time T (2). After T (3), the temperature of the nozzle hole portion 32 falls below the dew point. As a result, the time at which condensation occurs is slower when the heater is operating than when the heater is not operating, and therefore condensation occurs in the cylinder 24 at locations other than the injection hole portion 32. Therefore, when the middle graph and the lower graph in FIG. 5 are compared, the amount of water generated in a portion other than the nozzle hole portion 32 is increased, so that an increase in the water amount generated in the nozzle hole portion 32 is suppressed.

  As described above, according to the engine 10 according to the present embodiment, by operating the heater 34 during the operation of the engine 10, the injection hole portion 32 at the tip of the fuel injection valve 28 and the periphery thereof (particularly the heater 34). It is possible to suppress the temperature decrease or increase the temperature of the opposed tip portion. Therefore, even if the temperature of the nozzle hole 32 decreases after the engine 10 is stopped, the time until the temperature falls below the dew point is longer than when the heater 34 is not operated. As a result, dew condensation is promoted in the cylinder 24 at a location different from the nozzle hole portion 32 (particularly at a location away from the nozzle hole portion 32). Increase can be suppressed. Therefore, it is possible to provide an engine that suppresses an increase in the amount of moisture that condenses in the nozzle hole portion of the fuel injection valve after the engine stops and an increase in the amount of moisture that drops from the tip to the nozzle hole portion.

  In the present embodiment, the heater 34 is provided at a position corresponding to the outer peripheral side surface of the tip of the fuel injection valve 28. In this way, the heater 34 provided on the outer periphery of the tip including the nozzle hole portion 32 can suppress or increase the temperature drop of the nozzle hole portion 32 and its surroundings while the engine 10 is operating.

  In the present embodiment, ECU 200 activates heater 34 when water temperature Tw of engine 10 is smaller than threshold value Tw (0) during operation of engine 10. In this way, since the temperature of the nozzle hole 32 can be quickly raised, even when the engine 10 is stopped, an increase in the amount of moisture condensed on the nozzle hole 32 and its periphery can be suppressed.

  Furthermore, in the present embodiment, ECU 200 calculates an estimated value A (n) of the amount of condensed water generated by condensation based on the operating state of engine 10 during operation of engine 10. When the estimated value A (n) becomes larger than the threshold value E, the heater 34 is operated. In this way, the heater 34 can be operated when an increase in the amount of moisture that condenses in the nozzle hole 32 in the cylinder is predicted. Therefore, when the engine 10 is stopped, it is possible to reliably suppress an increase in the amount of moisture that is condensed at the nozzle hole portion 32.

Hereinafter, modified examples will be described.
In the present embodiment, the heater 34 is described as being provided in the cylinder head 18 and indirectly heating the injection hole portion 32. However, for example, the heater 34 is incorporated in the fuel injection valve 28 and has a tip portion (injection hole). It may be one that directly heats the periphery of the portion 32. Even if it does in this way, since the temperature of the nozzle hole part 32 can be raised during the operation | movement of the engine 10, the increase in the moisture content which dew condensation in the nozzle hole part 32 can be suppressed.

  In the present embodiment, the heater 34 is described as being provided so as to surround the tip including the periphery of the injection hole portion 32. However, for example, the heater 34 may surround only the periphery of the injection hole portion 32. For example, you may make it provide in the position facing a part of outer peripheral side surface of the front-end | tip of the fuel injection valve 28. FIG. For example, the heater 34 may be provided at a position corresponding to the outer peripheral side surface on the intake valve 22 side. In this way, the temperature on the intake valve 22 side tends to be lower than that on the exhaust valve 26 side on the outer peripheral side surface at the tip of the fuel injection valve 28. Therefore, by providing the heater 34 at a position facing the outer peripheral side surface on the intake valve 22 side, it is possible to suppress or increase the temperature of the injection hole portion 32 during operation of the engine 10.

  Further, in the present embodiment, ECU 200 calculates basic value B of the generation amount per unit time from engine speed NE, calculates first correction coefficient Ca from water temperature Tw, and performs second correction from intake air temperature Ti. The coefficient Cb is calculated, the second correction coefficient Cc is calculated from the EGR rate, and the basic value B is multiplied by the first correction coefficient Ca, the second correction coefficient Cb, and the third correction coefficient Cc, and the condensed water per unit time is calculated. Although it has been described that the estimated value C of the generation amount is calculated, it is not particularly limited to such a calculation method. For example, an estimated value C of the amount of condensed water generated per unit time corresponding to the operating state specified by the engine speed Ne, the water temperature Tw, the intake air temperature Ti, and the EGR rate is acquired in advance through experiments or the like. The ECU 200 stores an estimated value C of the amount of condensed water generated per unit time based on the engine speed NE, the water temperature Tw, the intake air temperature Ti, and the EGR rate. You may make it acquire from the said storage area.

  Furthermore, in the present embodiment, the ECU 200 has been described as a switch that is turned on when the heater 34 is operated, and a switch that is turned off when the heater 34 is stopped. When the temperature of the part 32 can be estimated or acquired, the switch operation of the heater 34 may be controlled so that the temperature of the nozzle hole part 32 becomes the target temperature. For example, the ECU 200 may turn off the switch when the temperature of the nozzle hole part 32 is equal to or higher than the target temperature, and may turn on the switch when the temperature of the nozzle hole part 32 is lower than the target temperature.

  Furthermore, the heater 34 in the present embodiment may have a function as a glow lamp, for example. Furthermore, the heater 34 may be in an ON state until a predetermined time after the engine 10 stops, for example.

In addition, you may implement combining the above-mentioned modification, all or one part.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  10 engines, 12 cylinder blocks, 14 pistons, 15 connecting rods, 16 piston rings, 18 cylinder heads, 20 intake ports, 22 intake valves, 24 cylinders, 26 exhaust valves, 28 fuel injection valves, 30 exhaust ports, 32 injection holes , 34 heater, 36 intake manifold, 38 exhaust manifold, 40 heat exchanger, 42, 44 EGR pipe, 46 EGR system, 200 ECU, 202 water temperature determination unit, 204 generation amount calculation unit, 206 generation amount determination unit, 208 heater control Part, 300 water temperature sensor, 302 rotation speed sensor, 304 intake air temperature sensor.

Claims (5)

A cylinder block having cylinders;
A cylinder head provided at the top of the cylinder;
A piston provided movably in the cylinder;
A fuel injection valve provided in the cylinder head and for injecting fuel into the cylinder;
A heater provided in the cylinder head and around the nozzle hole at the tip of the fuel injection valve;
An engine comprising: a control device that operates the heater during operation of the engine. The tip of the fuel injection valve has a cylindrical shape,
The engine according to claim 1, wherein the heater is provided at a position facing an outer peripheral side surface of the tip.   The engine according to claim 2, wherein the heater is provided at a position facing the outer peripheral side surface on the intake valve side.   The engine according to any one of claims 1 to 3, wherein the control device operates the heater when a cooling water temperature of the engine is lower than a threshold during operation of the engine.   The control device calculates an estimated value of the amount of condensed water generated by dew condensation based on the operating state of the engine during operation of the engine, and the calculated estimated value is larger than a threshold value. The engine according to any one of claims 1 to 3, wherein the heater is operated when it becomes.

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