JPH11303697A - Output control device for fuel burning heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal combustion engine with a suitable warming-up property and not to impair the heat resistance of a fuel burning heater in the internal combustion engine for circulating engine cooling water between an internal combustion engine body and the fuel burning heater, using a pump using the rotational force of a crankshaft as a driving source without using an electric pump. SOLUTION: This control device uses an engine 1 having a cooling water pump for flowing engine cooling water to a cooling water circulating passage 10, using the turning force of a crankshaft as a driving source and controls the output of a fuel burning heater 17 placed the cooling water circulating passage 10 and used for heating the engine cooling water. In this case, the output of the fuel burning heater 17 is controlled based on the temperature of the cooling water before heating by the fuel burning heater 17 and the temperature of the cooling water after heating by the fuel burning heater 17, respectively out of the cooling water flowing the cooling water circulating passage 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an output control device for a combustion type heater, and more particularly to an output control device for a combustion type heater for introducing combustion gas into an intake system of an internal combustion engine in order to promote warm-up of the internal combustion engine. .

[0002]

2. Description of the Related Art A technique for heating engine cooling water of an internal combustion engine with a combustion heater is well known.
No. 152. This publication discloses a technique in which engine cooling water is forcibly circulated by an electric pump between a water jacket of an internal combustion engine and a combustion heater. When the cooling water is circulated between the water jacket of the internal combustion engine and the combustion type heater using the electric pump in this manner, the circulation amount of the engine cooling water is kept constant regardless of the operation state of the internal combustion engine, or Within the range.

On the other hand, it is conceivable to circulate engine cooling water between a water jacket of an internal combustion engine and a combustion type heater using a pump driven by the rotational force of a crankshaft without using an electric pump.

[0004]

However, in such a technique that does not use an electric pump, the amount of circulating cooling water is not constant but varies depending on the engine speed of the internal combustion engine. Therefore, even though the amount of heat received by the cooling water from the combustion heater is constant, the temperature rise is not constant. Therefore, if the output control of the combustion heater is performed without considering the temperature rise due to the amount of heat received from the combustion heater of the cooling water, the engine warm-up performance may be reduced, or the output of the combustion heater may be required. As a result, the heat resistance of the combustion heater may be impaired.

[0005] The present invention has been made in view of such a situation, and the problem to be solved is to use a pump that uses the rotational force of a crankshaft as a drive source without using an electric pump. An internal combustion engine that circulates engine cooling water between an internal combustion engine main body and a combustion type heater, wherein the combustion type heater not only can preferably warm up the internal combustion engine but also does not impair the heat resistance of the combustion type heater. It is a technical object to provide an output control device.

[0006]

In order to solve the above-mentioned problems, an output control device for a combustion type heater according to the present invention has the following configuration.

That is, the output control apparatus for a combustion type heater according to the present invention is used in an internal combustion engine having a cooling water pump for flowing engine cooling water into a cooling water circulation passage by using the rotational force of a crankshaft as a drive source. What is claimed is: 1. An output control device for a combustion type heater which is arranged on a cooling water circulation passage and controls an output of a combustion type heater for warming the engine cooling water, the combustion type heater output control device comprising: a cooling water flowing through the cooling water circulation passage. The output of the combustion heater is controlled based on the respective temperatures of the cooling water before heating by the combustion heater and the cooling water after heating by the combustion heater.

[0008] The "combustion heater disposed on the cooling water circulation passage to warm the engine cooling water" is provided with a cooling water passage through which the cooling water flows inside the combustion heater, and the cooling water is cooled by the cooling water. While passing through the passage, heat is received from the combustion chamber of the combustion type heater to heat the cooling water.

In the output control device for a combustion type heater according to the present invention, of the cooling water flowing through the cooling water circulation passage, the respective temperatures of the cooling water before the heating by the combustion type heater and the cooling water after the heating by the combustion type heater are set. The output of the combustion type heater is controlled based on Therefore, the heating state of the cooling water by the combustion heater can be grasped from the temperature of the cooling water after the heating by the combustion heater, and the output control of the combustion heater can be controlled from this heating state. At this time, if the circulation amount of the cooling water changes according to the rotation speed of the internal combustion engine, the warmed-up state of the internal combustion engine cannot be grasped only from the cooling water temperature after the heating. However, in the present invention, the temperature before the cooling water is heated by the combustion type heater is also considered, and the output of the combustion type heater is controlled based on this temperature. Therefore,
Heating of the cooling water by the combustion type heater can be performed without excess or shortage.
Therefore, there is no danger that the engine warm-up performance will be reduced or the output of the combustion type heater will be increased more than necessary, thereby impairing the heat resistance of the combustion type heater. (2) When the temperature of the cooling water after the heating is equal to or higher than a predetermined temperature, the output of the combustion type heater may be reduced.

In this case, the combustion type heater can be prevented from being heated. (3) When the temperature of the cooling water before the heating is low, the value of the predetermined temperature may be increased.

In an internal combustion engine provided with a cooling water pump for flowing engine cooling water through a cooling water circulation passage using the rotational force of a crankshaft as a drive source, the amount of cooling water circulated is small when the engine speed is low. However, when the output of the combustion heater is higher than the circulation amount of the cooling water, the temperature after the heating of the cooling water by the combustion heater is sufficiently high. However, even if the amount of cooling water is small, warming up of the internal combustion engine is not necessarily promoted. This is because a sufficient amount of cooling water and this cooling water must have received sufficient heat in order to promote warm-up.

In the present invention, even if the amount of cooling water is not sufficient,
This is compensated for by increasing the cooling water temperature, so that if the temperature before heating of the cooling water by the combustion heater is in a low temperature state, the predetermined temperature related to the cooling water temperature after heating is increased. Therefore, the warm-up of the combustion heater is more effectively promoted. (4) The temperature of the cooling water before the heating is preferably measured at or near an outlet of a cooling water passage provided in the internal combustion engine body.

Here, "the cooling water passage provided in the internal combustion engine body" means a water jacket.

"Near the outlet of the cooling water passage provided in the internal combustion engine body" means "from the outlet of the cooling water passage of the internal combustion engine body to the inlet of the cooling water passage of the combustion heater" in the cooling water circulation passage of the internal combustion engine. The part between them shall be referred to.

Since the temperature of the cooling water before heating by the combustion type heater is measured at or near the outlet of the cooling water passage provided in the internal combustion engine main body, the temperature of the internal combustion engine main body, that is, the actual warm-up temperature can be accurately measured. . (5) The temperature of the cooling water after the heating may be measured at or near the outlet of the combustion heater.

Here, "in the vicinity of the outlet of the combustion type heater" means a portion of the cooling water circulation passage of the internal combustion engine which can detect a temperature value having a small error from the outlet temperature of the cooling water passage of the combustion type heater. Shall be.

Since the temperature of the cooling water after heating by the combustion heater is measured at or near the outlet of the combustion heater, the actual temperature in the combustion heater can be accurately measured.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. <Overall Description of Apparatus> The engine 1 as an internal combustion engine is of a water-cooled type, and includes an engine body 3, an intake device 5 for feeding air necessary for combustion into a plurality of cylinders (not shown) of the engine body 3, An exhaust system 7 for discharging exhaust gas after the air-fuel mixture burns into the atmosphere, and a vehicle interior heater 9 for warming the interior of a vehicle on which the engine 1 is mounted. Further, the engine 1 is provided with a cooling water pump (not shown) for flowing engine cooling water into a cooling water circulation passage 10 described below using the rotational force of a crankshaft (not shown) as a drive source. <Description of Device Components> (Engine Body 3) The engine body 3 includes a water jacket, which is a cooling water passage (not shown) through which cooling water circulates. Then, starting from the water jacket, the combustion type heater 17 and the engine body 3 belonging to the intake device 5 via the water pipes W1, W2 and W3.
Cooling water circulation passage 1 circulating between exterior cabin heaters 9
0 is formed. (Intake device 5) The intake device 5 uses an air cleaner 13 that takes in fresh air into a cylinder as a start end of the intake device 5.
A compressor 15a of a turbocharger 15, which is an intake system structure, a combustion heater 17, and an intercooler 19, are provided between the air cleaner 13 and an intake port (not shown) of the engine body 3, which is the end of the intake device 5.
And an intake manifold 21.

These intake system structures belong to an intake pipe 23 having a plurality of connecting pipes. (Intake pipe 23) The intake pipe 23 is connected to the compressor 15a so that the outside air entering the intake device 5 is separated from the compressor 15a.
Thus, the downstream connecting pipe 27 is forcibly pushed into the pressurized state, and the upstream connecting pipe 25 which is not forcibly pushed. (Upstream Connection Pipe 25) The upstream connection pipe 25 includes a rod-shaped main pipe 29 extending straight from the air cleaner 13 toward the compressor 15 a, and a heater branch as a branch pipe connected to the main pipe 29 in a bypass shape. And a tube 31. (Branch 31 for heater) The branch 31 for heater includes the combustion type heater 17 in the middle thereof, connects the upstream side portion of the combustion type heater 17 in the air flow direction with the main flow tube 29, and Combustion (exhaust) gas that connects the air supply passage 33 that supplies fresh air, that is, air, to the combustion heater 17, the downstream portion of the combustion heater 17 in the direction of air flow, and the main pipe 29 and that exits from the combustion heater 17. And a combustion gas discharge path 35 for discharging the gas to the main pipe 29. In addition,
The air relating to the heater branch pipe 31 does not only mean fresh air a1 entering the heater branch pipe 31 via the air cleaner 13, but also means that the combustion gas a exiting from the combustion type heater is not limited to the fresh air a 1.
Also means 2. The combustion gas of the sintering heater is a gas that has almost no smoke, in other words, does not contain carbon. Therefore, there is no problem in using it as intake air for an internal combustion engine.

The connection point c1 of the air supply path 33 and the connection point c1 of the combustion gas discharge path 35 with the main pipe 29 is located upstream of the main pipe 29 with respect to the connection point c2. Therefore, the air a1 from the air cleaner 13 is first supplied to the heater branch pipe 31 at the connection point c1.
The main flow pipe 29 is divided into air a1 'heading toward the connection point c2 without branching. Further, at the connection point c2, the air a2 branched at the connection point c1 and subjected to the combustion of the combustion type heater 17 to become the combustion gas merges with the fresh air a1 ′ not branched at the connection point c1 to mix the combustion gas. Air a
It becomes 3.

The air a1 branched at the connection point c1 returns to the main pipe 29 as air a2 from the connection point c2 via the air supply path 33, the combustion heater 17 and the combustion gas discharge path 35. Since the air a2 returning to the main pipe 29 is a combustion gas having heat generated by the combustion of the combustion heater 17, this gas is returned to the main pipe 29 to be connected to the air a1 'which has not branched. When it joins at the point c2 to become the combustion gas mixed air a3, as a result, the combustion gas mixed air a3
Is high-temperature intake air that enters the engine body 3.

In FIG. 1, the downstream connecting pipe 27
Is the compressor 15a and the intake manifold 21
The tube shown in FIG. 1 has an L-shape. Further, an intercooler 19 is arranged at a position near the intake manifold 21.

(Exhaust Device 7) On the other hand, the exhaust device 7 has an exhaust port (not shown) of the engine body 3 as a start end of the exhaust device 7, and an exhaust manifold 37, between the exhaust port 7 and the muffler 41 at the end of the exhaust device 7. The turbine 15 b of the turbocharger 15 and the exhaust catalyst 39 are connected to an exhaust pipe 42.
Have prepared above. Since these are well known and do not directly relate to the present invention, the description will be omitted. The air flowing through the exhaust device 7 is denoted by a4
Indicated by (Combustion type heater 17) The structure of the firing type heater 17 will be described with reference to FIG.

The combustion type heater 17 is connected to the water jacket of the engine body 3 through a water pipe W1, and the combustion type heater 17 has a cooling water passage 17a through which cooling water from the water jacket passes. Have.

The cooling water flowing through the cooling water passage 17a (indicated by a broken line arrow in the figure) passes around a combustion chamber 17d, which is a combustion section formed inside the combustion type heater 17, and passes therethrough. The heat is received by the heat from the combustion chamber 17d. This will be described in detail in order.

The combustion chamber 17d includes a combustion tube 17b as a combustion source for emitting a flame, and a cylindrical partition wall 17c that covers the combustion tube 17b to prevent the flame from leaking to the outside. By covering the combustion cylinder 17b with the partition wall 17c, the combustion chamber 1
7d is defined in the partition wall 17c. And this partition 17
c is also covered with the outer wall 43a of the combustion chamber main body 43 of the combustion type heater 17, and there is a space between them. By providing this space, the cooling water passage 17a is formed between the inner surface of the outer wall 43a and the outer surface of the partition wall 17c.

The combustion chamber 17d is connected to the air supply passage 3
3 and an air discharge port 17d2 directly connected to the combustion gas discharge path 35, respectively.

The air a1 flowing from the air supply path 33
When the air enters the combustion chamber 17d from the air supply port 17d1, the air flows through the combustion chamber 17d to reach the exhaust discharge port 17d2, and then flows through the combustion gas discharge path 35 into the main pipe 29 as the air a2 as described above. enter. Therefore, the combustion chamber 17d is in the form of an air passage through which the air a1 changed by combustion passes through the air a2 in the combustion type heater 17.

Then, after the combustion type heater 17 burns,
Air a returning to the main pipe 29 via the combustion gas discharge passage 35
Reference numeral 2 denotes an exhaust gas emitted from the combustion heater 17 and thus has heat. Until the heated air a2 exits the combustion heater 17, the heat of the air a2 is transmitted to the cooling water flowing through the cooling water passage 17a through the partition wall 17c, and the cooling water is supplied as described above. warm.
Therefore, the combustion chamber 17d is also a heat exchange passage.

The combustion cylinder 17b is provided with a fuel supply pipe 17e connected to a fuel pump (not shown), and supplies the fuel for combustion to the combustion cylinder 17b by receiving the pump pressure of the fuel pump therefrom. The supplied combustion fuel is vaporized in the combustion heater 17 to become vaporized fuel, and the vaporized fuel is ignited by an ignition source (not shown).

The air supply passage 33 and the combustion gas discharge passage 3
5 is used only for the combustion type heater 17. Therefore, they belong to the combustion heater 17. (Cooling water circulation) Next, the cooling water circulation will be described.

The cooling water passage 17a is provided with a cooling water inlet 17a1 connected to the water jacket of the engine body 3.
And a cooling water discharge port 17a2 connected to the vehicle interior heater 9.

The cooling water inlet 17a1 is connected to the engine body 3
The cooling water discharge port 17a2 is connected to the vehicle interior heater 9 via the water pipe W2. These water pipes W1
The combustion heater 17 is connected to the water jacket of the engine body 3 and the vehicle interior heater 9 via W2 and W2. Also, the heater 9 for the passenger compartment and the engine body 3
Are also connected via a water pipe W3. In addition, the water pipe W
No. 1 connection point with water jacket and water pipe W2
Water temperature sensors 40a and 40b are attached to the connection points with the combustion type heater 17 respectively. These water temperature sensors 40a and 40b are electrically connected to an engine electronic control unit (ECU) 46 for controlling the operation of the entire engine.

By connecting the engine body 3, the combustion type heater 17, and the vehicle interior heater 9 using the water pipes W1, W2, and W3 in this manner, the cooling water in the water jacket of the engine body 3 is cooled. , The cooling water circulation passage 10 is formed in the following order, and returns to the water jacket again and repeats the above.

The circulation of the cooling water will be described in detail. The cooling water flows from the water jacket to the combustion heater 17 from the cooling water inlet 17a1 via the water pipe W1.
There they are warmed.

The cooling water warmed in the above-described manner reaches the vehicle interior heater 9 from the cooling water discharge port 17a2 of the combustion type heater 17 via the water pipe W2.

Then, the cooling water is subjected to heat exchange in the vehicle interior heater 9 and its temperature is lowered, or, if the operation of the vehicle interior heater 9 is stopped, the cooling water passes without heat exchange. , And returns to the water jacket via the water pipe W3. (Other components of the combustion chamber main body 43)
3 includes a blower fan 45 and a central processing controller (CPU) 47 that exclusively controls operation of the combustion heater 17 that is separate from an engine electronic control unit (ECU) 46. If the combustion heater 17 is controlled by a CPU (not shown) of the ECU 46, the combustion heater 1
The CPU 47 may be omitted. (ECU 46 and related members electrically connected thereto) The ECU 46 includes various sensors such as an outside air temperature sensor, a combustion gas temperature sensor, and a rotation speed sensor (not shown), a blower fan 45 and a fuel pump (not shown).
It is electrically connected via PU47.

Then, the CPU 47 of the combustion type heater 17 operates according to each parameter of the various sensors, thereby controlling the combustion state of the combustion type heater 17. In other words, the CPU 47 controls the momentum, the size, the temperature, and the like of the flame of the combustion type heater 17, and controls the temperature of the exhaust gas (combustion gas) of the combustion type heater 17 by this control.

The water pipe W1 is connected to the water jacket, that is, the temperature detected by the water temperature sensor 40a provided at the outlet of the water jacket, and the water pipe W2
The temperature detected by the water temperature sensor 40b provided at the connection point with the combustion type heater 17, that is, at the outlet of the combustion type heater,
The engine outlet water temperature and the combustion-type heater outlet water temperature are denoted by T1 and T2, respectively. These water temperatures T1 and T2 can be said to be the cooling water temperature before being heated by the combustion type heater 17 and the cooling water temperature after being heated by the combustion type heater 17, respectively.

Of the cooling water flowing through the cooling water circulation passage 10, the temperature of the cooling water before heating by the combustion heater 17 and the temperature of the cooling water after heating by the combustion heater 17 are determined based on the temperatures T 1 and T 2 of the combustion heater 17. What controls the output is the output control device of the combustion type heater according to the embodiment of the invention.

(Operation Control Routine) Next, the operation control routine of the output control device of the combustion type heater will be described with reference to the flowchart of FIG.

This routine is a part of a normal flowchart (not shown) for driving the engine 1 and includes steps 101 to 108 described below. Also,
All operations in the following procedure are performed by the ECU 46. Then, using the symbol S, for example, step 101
In this case, it is abbreviated as S101.

After the start of the engine 1, when the process proceeds to this routine, in S101, it is determined whether or not the engine outlet water temperature (temperature before heating by the combustion type heater) T1 is equal to or lower than the temperature TT1 before complete warm-up. . The temperature before complete warm-up TT1 is, for example, 75 ° C.
Can be mentioned. Note that the temperature at the time of completion of warm-up is, for example, 90 ° C.

When the determination in S101 is affirmative, the engine outlet water temperature T1 becomes equal to the temperature TT1 before the completion of the complete warm-up (75 in the above example).
° C) or less, proceed to the next S102, make a negative determination,
The engine outlet water temperature T1 is the temperature TT1 before the completion of the complete warm-up.
If it is higher than the above (75 ° C. in the above example), the process proceeds to S103.

In S102, the predetermined temperature TT required for controlling the output of the combustion heater 17 is set to TT2 + A, and in S103, the predetermined temperature TT is set to a fixed value TT2. Here, TT2 is 85 ° C. in the present embodiment. A is also a fixed value, and is 10 ° C. in this embodiment.
It is. Therefore, since TT2 + A is an addition value between the fixed values, it is also a fixed value, for example, 95 ° C. However, the value of A may be a variable value. S102 and S103
After the predetermined temperature TT has been set in step, the process proceeds to the next step S104.

In step S104, the water temperature T at the outlet of the combustion type heater is determined.
2 is determined to be equal to or higher than a predetermined temperature TT. S1
When the determination is affirmative in 04, the process proceeds to S105, and when the determination is negative, the process proceeds to S106. The predetermined temperature TT is S10
4 for comparison with T2.
That.

In S105, the output value W of the combustion heater 17 is set to a low output value Lo or 0 (zero), and thereafter, the process proceeds to S108.

In step S106, the water temperature T at the outlet of the combustion type heater is determined.
2 is based on the temperature TT-B lower than the comparative temperature TT by B, and it is determined whether or not the combustion heater outlet water temperature T2 is a value lower than that. Where B is a fixed value,
In this embodiment, the temperature is 20 ° C. If the determination in S106 is affirmative, the routine proceeds to the next S107, where the combustion type heater 17
Is set to Hi, and the process proceeds to S108. On the other hand, if a negative determination is made in S106, the process proceeds to S108 without going through S107. Since the output value W of the combustion type heater 17 is aimed at Hi, Lo or 0, the output value W of the combustion type heater 17 is hereinafter referred to as “target output value W” unless otherwise specified.

In S108, the combustion type heater 17 sets
The output of the combustion type heater 17 is controlled so as to operate at the target output value W set in S05 or S107.
When the output value Lo or 0 set in S105 is set as the target output value W, the actual output of the combustion type heater 17 becomes a low output (or stops). Also, the target output value W
Is set to the output value Hi set in S107,
The actual output of the combustion heater 17 is high.

Next, an output control state of the combustion heater 17 when the flowchart of FIG. 3 is executed will be described with reference to FIG.

The vertical axis in FIG. 4 indicates the degree of output of the combustion heater 17, and the horizontal axis indicates the outlet water temperature T2 of the combustion heater. The broken line in FIG. 4 indicates the engine outlet temperature T
1 indicates the output control state of the combustion heater 17 when the temperature is not higher than the complete warm-up completion temperature TT1 (75 ° C. in the above example) (when shifting from S101 to S102), and the solid line indicates that the engine outlet temperature T1 is completely warmed. The output control state of the combustion heater 17 when the temperature is higher than the pre-completion temperature TT1 (75 ° C. in the above example) (when shifting from S101 to S103) is shown.

The meaning of the broken line means that when the engine outlet temperature T1 is higher than the pre-complete warm-up completion temperature TT1 (75 ° C. in the above example), the combustion heater outlet water temperature T2 becomes TT2 + A (for example, 95 ° C.). ) Indicates that the output of the combustion heater 17 switches from the high output to the low output. Then, by setting the combustion heater 17 to a low output in this way, when the combustion heater outlet water temperature T2 becomes TT2 + AB (for example, 75 ° C.), the combustion heater 17 switches from a low output to a high output. It means to switch. Here, a hysteresis is provided by B (for example, 20 ° C.) between the time when the output is switched from the low output to the high output and the time when the output is switched from the high output to the low output. Hunting is prevented.

The solid line means that when the engine outlet temperature T1 is equal to or lower than the pre-complete warm-up completion temperature TT1 (75 ° C. in the above example), the combustion heater outlet water temperature T2 becomes TT2 (for example, 85 ° C.). (° C.), the output of the combustion type heater 17 is switched from a high output (the position of Hi on the vertical axis) to a low output (the position of Lo or 0 on the vertical axis). Then, when the output of the combustion heater 17 becomes low as described above and the outlet water temperature T2 of the combustion heater becomes TT2-B (for example, 65 ° C.), the combustion heater 17 then turns from the low output to It means switching to high output. Here, between the time of switching from low output to high output and the time of switching from high output to low output, hysteresis is provided by B (for example, 20 ° C.) as in the case of the broken line. This prevents hunting that may occur when the output is switched.

As described above, when the water temperature T2 at the outlet of the combustion type heater becomes high, the output of the combustion type heater 17 is switched from high output to low output regardless of whether the line is a solid line or a broken line. To prevent a decrease in durability.

On the other hand, the engine outlet water temperature T1 shown by the solid line
Is higher than the temperature TT1 before the completion of the complete warm-up, the temperature TT2 at which the combustion heater 17 switches from high output to low output.
In contrast, when the engine outlet water temperature T1 indicated by the broken line is equal to or lower than the temperature TT1 before complete warm-up, the switching temperature TT2 + A of the combustion type heater 17 from high output to low output is higher. Therefore, when the warm-up of the engine 1 is insufficient and the engine outlet water temperature T1 is low, a decrease in the output of the combustion heater 17 is suppressed, and a decrease in the warm-up property of the engine 1 can be prevented. <Operation and Effect of Embodiment> Next, the operation and effect of the output control device for a combustion heater according to the embodiment will be described.

In the output control device of the combustion heater, the cooling water flowing through the cooling water circulation passage 10 is based on the temperatures of the cooling water before heating by the combustion heater 17 and the cooling water after heating by the combustion heater 17. , The output of the combustion heater 17 is controlled. Therefore, the heating state of the cooling water by the combustion type heater 17 can be grasped from the temperature of the cooling water after the heating by the combustion type heater 17, and the output of the combustion type heater 17 can be controlled from this heating state. At this time engine 1
If the amount of circulation of the cooling water changes depending on the number of rotations, the warm-up state of the engine 1 cannot be grasped only by the temperature of the cooling water after heating. However, in the engine 1 according to this embodiment, the temperature before the cooling water is heated by the combustion heater 17 is also taken into consideration, and the combustion heater 1 is determined based on this temperature.
7 is controlled. Therefore, the heating of the cooling water by the combustion type heater 17 can be performed without excess or shortage. Therefore, there is no danger that the engine warm-up performance is reduced or the output of the combustion heater becomes unnecessarily high and the heat resistance of the combustion heater 17 is impaired.

In the engine 1, when the engine speed is low, the rotation speed of the cooling water pump (not shown) is also low, so that the amount of cooling water flowing through the cooling water circulation passage 10 is small. However, the combustion type heater 17
Is high, the temperature after the cooling water is heated by the combustion heater 17 is sufficiently high. However, even if the amount of cooling water is small, warming up of the engine 1 is not necessarily promoted. This is because a sufficient amount of cooling water and this cooling water must have received sufficient heat in order to promote warm-up. However, in the engine 1, when the temperature of the coolant before heating by the combustion heater 17 is low, the predetermined temperature related to the coolant temperature after heating is increased. The warm-up is more effectively promoted.

Further, since the temperature of the cooling water before heating by the combustion type heater 17 is measured at or near the outlet of the water jacket provided in the engine main body 3, the temperature of the engine main body 3, that is, the actual warm-up temperature is accurately measured. Can be measured.

Since the temperature of the cooling water after heating by the combustion heater 17 is measured at or near the outlet of the combustion heater 17, the actual temperature of the combustion heater 17 can be accurately measured.

[0060]

As described above, according to the present invention, engine cooling is performed between an internal combustion engine body and a combustion type heater by using a pump driven by the rotational force of a crankshaft without using an electric pump. In an internal combustion engine that circulates water,
Not only can the warm-up property of the internal combustion engine be improved, but also the heat resistance of the combustion heater is not impaired.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an internal combustion engine having a combustion heater according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a combustion type heater.

FIG. 3 is a flowchart showing an operation control routine of an internal combustion engine having a combustion heater according to the embodiment of the present invention;

FIG. 4 is a diagram showing an output control state of a combustion heater 17 when the flowchart of FIG. 3 is executed.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine (internal combustion engine) 3 ... Engine main body (internal combustion engine main body) 5 ... Intake device 7 ... Exhaust device 9 ... Heater for vehicle compartment 10 ... Cooling water circulation passage 13 ... Air cleaner 15 ... Turbocharger 15a ... Compressor 15b ... Turbocharger Turbine 17 Combustion heater 17a Cooling water passage 17a1 Cooling water inlet 17a2 Cooling water outlet 17b Combustion cylinder 17c Cylindrical partition wall 17d Combustion chamber 17d1 Air supply port 17d2 Exhaust discharge port 17e Fuel supply pipe 19 Intercooler 21 Intake manifold 23 Intake pipe 25 Upstream connection pipe 27 Downstream connection pipe 29 Main flow pipe 31 Heater branch pipe 33 Air supply path 35 Combustion gas discharge path 37: Exhaust manifold 39: Exhaust catalyst 40a: Water temperature sensor 40b: Water temperature sensor 41 muffler 42 exhaust pipe 43 combustion chamber main body 43a outer wall 45 blower fan 46 ECU 47 CPU c1 connection point between air supply path 33 and main pipe 29 c2 combustion gas discharge path 35 and main pipe 29 Connection point with T: engine outlet water temperature T1 ... water temperature sensor 4 provided at the outlet of the water jacket
Temperature detected by Oa (temperature of cooling water before heating) T2: Temperature detected by water temperature sensor 40b provided at the outlet of the combustion type heater (temperature of cooling water after heating) TT: Comparative temperature (predetermined temperature) TT1 ... Temperature before complete warm-up (set temperature) TT2 ... fixed value TT2 + A ... fixed value A ... fixed value B ... hysteresis W ... target output value of combustion type heater 17 W1 ... water pipe W2 ... water pipe W3 ... water pipe a1 ... air cleaner 13 Outside air (fresh air) coming into the main pipe 29 from the outlet a1 '... air flowing to the main pipe 29 without branching at the connection point c1 a2 ... provided to the combustion of the combustion heater 17 to become combustion gas Air a3: Air mixed with combustion gas a4: Exhaust gas of engine 1

Claims (5)

[Claims] 1. An internal combustion engine provided with a cooling water pump for flowing engine cooling water through a cooling water circulation passage using a rotational force of a crankshaft as a drive source, and disposed on the cooling water circulation passage to warm the engine cooling water. An output control device of a combustion type heater for controlling an output of a combustion type heater, wherein the combustion type heater output control device comprises: An output control device for a combustion-type heater, wherein the output of the combustion-type heater is controlled based on each temperature of the cooling water heated by the type-type heater. 2. The output control device for a combustion type heater according to claim 1, wherein when the temperature of the cooling water after the heating is equal to or higher than a predetermined temperature, the output of the combustion type heater is reduced. 3. The output control device for a combustion type heater according to claim 2, wherein when the temperature of the cooling water before the heating is low, the value of the predetermined temperature is increased. 4. The cooling water according to claim 1, wherein the temperature of the cooling water before heating is measured at or near an outlet of a cooling water passage provided in the internal combustion engine body. Output control device for combustion type heater. 5. The output of the combustion type heater according to claim 1, wherein the temperature of the cooling water after the heating is measured at or near an outlet of the combustion type heater. Control device.