JP3358557B2 - Vehicle heating system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device for a vehicle having a combustor for heating the interior of a vehicle by burning fuel. The invention relates to a vehicle equipped with an internal combustion engine such as a diesel engine having a small amount of waste heat. It is effective to apply.

[0002]

2. Description of the Related Art In a vehicle in which the interior of a vehicle is heated by using waste heat of an internal combustion engine (hereinafter abbreviated as an engine) as a heat source, a so-called cold start immediately after the start of the engine is performed.
Alternatively, a diesel engine having a small amount of waste heat cannot exhibit a sufficient heating capacity, so the applicant has already applied for a heating device for a vehicle (Japanese Patent Application No. 10-161024) for supplementing the heating capacity with a combustor. ing.

[0003]

However, since the exhaust pressure of the combustor is smaller than the exhaust pressure of the engine, if the exhaust side of the combustor and the exhaust side of the engine are simply connected, when the engine is operating, However, since the exhaust of the engine flows back to the combustor, it is difficult to stably burn the combustor.

Therefore, in the above-mentioned application, although the combustor is stably burned by pumping air to the combustor using a volume (volume) type blower (air pump), a volume type blower is required. Therefore, there is a problem that the manufacturing cost of the vehicle heating device is increased. In addition, there is a problem that a piping for discharging exhaust gas from the combustor to the atmosphere is required, which complicates an exhaust system layout.

In view of the above, it is an object of the present invention to stably burn a combustor while suppressing an increase in the manufacturing cost of a heating device for a vehicle.

[0006]

The present invention uses the following technical means to achieve the above object. According to the first aspect of the present invention, the exhaust pipe (13) for discharging the exhaust gas of the internal combustion engine (10) into the atmosphere is guided by the exhaust pipe (13).
A vehicle heating device applied to a vehicle having a catalyst (14) for purifying exhaust gas and a muffler (15) for reducing exhaust noise, wherein a vehicle interior is heated using waste heat of the internal combustion engine (10) as a heat source. Heating means (20), and a combustor (21) for heating the vehicle interior by burning fuel,
When the internal combustion engine (10) is stopped, the combustion machine (2
The exhaust gas of (1) is passed through the catalyst (1) in the exhaust pipe (13).
4) and discharge to the upstream side of the muffler (15).
Switching the exhaust passage of the combustor (21) to said internal combustion
During operation of the engine (10), the exhaust of the combustor is
The combustion engine so as to discharge to an intake side of a combustion engine (10).
The exhaust path of (21) is switched, and the combustor (21) is
When the OFF signal for stopping is generated, the combustion machine is stopped.
The exhaust gas is discharged to the intake side of the internal combustion engine (10).
The exhaust path of the combustor (21) is switched .

[0007] Thus, without using a body volume (volume) type blower, the exhaust gas of the internal combustion engine (10) combustor (2
Runode it is possible to prevent the backflow to want it to 1),
The combustor (21) can be stably burned. Therefore, according to the vehicle heating device of the present invention, the combustor (21) can be stably burned while suppressing an increase in manufacturing cost, and the layout of the exhaust system of the combustor (21) is simplified. Combustion machine (21)
Vehicle mountability can be improved.

[0008]

[0009]

[0010] Cause Mini, reference numerals in parentheses of the above means are examples showing the correspondence with specific means described in embodiments described later.

[0011]

(First Embodiment) FIG. 1 is a schematic view of a vehicle heating device according to the present embodiment, and 10 is a water-cooled diesel engine (liquid-cooled internal combustion engine) for running the vehicle. . Reference numeral 11 denotes an intake pipe for guiding the air from which dust has been removed (purified) by the air cleaner 12 to each cylinder of a water-cooled diesel engine (hereinafter abbreviated as engine). Reference numeral 13 denotes an exhaust pipe from each cylinder. To collect the exhaust
This is an exhaust pipe leading to a catalyst 14 described later.

Reference numeral 14 denotes a three-way catalyst (hereinafter abbreviated as a catalyst) for purifying the exhaust gas by promoting an oxidation-reduction reaction such as hydrocarbon or nitrogen oxidation in the exhaust gas. Is provided with a muffler (muffler) 15 for reducing noise (exhaust sound) of exhaust gas flowing out of the catalyst 14. Reference numeral 16 denotes a radiator that cools cooling water (cooling liquid) circulating in the engine 10, and reference numeral 17 denotes a water pump that circulates cooling water by obtaining driving force from the engine 10. Reference numeral 18 denotes a bypass passage for returning the cooling water flowing out of the engine 10 to the engine 10 by bypassing the radiator 16, and 19 denotes a case where the cooling water flowing out of the engine 10 flows through the radiator 16 according to the cooling water temperature. Is a known thermostat that switches between a case where the gas flows through the bypass passage 18.

Incidentally, the water pump 17 and the bypass passage 18 are usually built in the engine 10.
Reference numeral 20 denotes a heater core (heating means) for heating the vehicle interior by heating the air blown into the vehicle interior using the cooling water as a heat source. This is a combustor that heats the cooling water to be heated.

The combustion state of the combustor 21 (stopped or the calorific value of the combustor 21), a fuel pump (F / P) 22 for pumping fuel to the combustor 21, and an electric water pump 23
Is controlled by an electronic control unit (ECU) 24 based on a set value of a timer switch (not shown) or a remote control device (not shown) operated by an occupant and a detection signal (detection temperature) of the water temperature sensor 24a. You.

Incidentally, the water temperature sensor 24a (temperature detecting means) is a water temperature sensor for detecting the temperature of the cooling water flowing out of the engine 10. Reference numeral 25 denotes a bypass passage which guides the cooling water flowing out of the engine 10 to the combustor 21 by bypassing the electric water pump 23. In the bypass passage 25, cooling water discharged from the electric water pump 23 is provided. 25 and the electric water pump 2
A check valve 26 for preventing reflux is provided on the suction side of No. 3.

Reference numeral 27 denotes a combustor 2 which inhales the air purified by the air cleaner 12 from the intake pipe 11 of the engine 10.
1 is an electric blower (hereinafter, abbreviated as a blower), and in this embodiment, a turbo blower is used. In addition, a turbo blower refers to a machine that gives kinetic energy to gas by the rotational movement of an impeller, and specifically refers to a centrifugal blower, a mixed flow blower, an axial blower, and the like (JIS).
B 0132).

Reference numeral 28 denotes a first exhaust duct (first exhaust pipe) for guiding the exhaust gas discharged from the combustor 21 to the catalyst 14. The exhaust duct 28 is connected to the exhaust pipe 13 on the upstream side of the exhaust gas from the catalyst 14. It is connected. Reference numeral 29 denotes a second exhaust duct (second exhaust pipe) for guiding the exhaust gas of the combustor 21 to the intake pipe 11 of the engine 10. A switching valve 30 is provided for switching between flowing the exhaust gas through the exhaust duct 28 and flowing the exhaust gas from the combustor 21 through the second exhaust duct 29.

In the present embodiment, the switching valve 30 is an electric switching valve that operates a valve element by a stepping motor, and the switching valve 30 is controlled by the ECU 24. Next, the operation of the vehicle heating device according to the present embodiment will be described based on the flowchart shown in FIG.

First, a signal from a timer switch or a remote control device is read into the ECU 24 (S100), and it is determined whether or not the signal ignites (operates) the combustor 21 (ON signal) (OFF signal). Is performed (S110). When it is determined that the signal is the OFF signal, the exhaust of the combustor 21 is switched to the second valve by the switching valve 30.
The state where the fuel flows through the duct 29 (hereinafter, this state is referred to as position A) (S120), and the combustor 21
Is stopped (S130). When the combustor 21 has already stopped, the stopped state (OFF state) is maintained.

If it is determined in S110 that the signal is an ON signal, the engine 1 is controlled based on an ignition signal to an ignition coil (not shown) of the engine 10.
It is determined whether 0 is operating (ON) or not (OFF) (S140). When the engine 10 is operating, the switching valve 30 is set to the position A (S150), and the fuel pump 22 and the blower 27 are turned on. The combustor 21 is operated (ignited) by operating (S160). When the combustor 21 is already operating, the operating state (ON state) is maintained.

On the other hand, when the engine 10 is stopped, the switching valve 30 is set to a state in which the exhaust gas of the combustor 21 flows through the first duct 28 (hereinafter, this state is referred to as a position B). S170), the fuel pump 22, the electric water pump 23 and the blower 27 are operated to
1 is operated (ignited) (S160). When the combustor 21 is already operating, the operating state (ON state)
To maintain.

When the combustor 21 operates, the engine 10
Operates, the engine 10 draws in the exhaust of the combustor 21 together with the intake air and burns (explodes). Therefore, the fuel injection device (not shown) of the engine 10
Due to the fact that the exhaust gas of the combustor 21 is mixed into the intake air,
It is necessary to perform fuel injection in consideration of a decrease in the amount of oxygen in the intake air.

Next, the features of this embodiment will be described. When the engine 10 is stopped, the exhaust of the combustor 21
The catalyst 14 flows through the exhaust duct 28 and is guided to the catalyst 14.
After the noise is reduced by the muffler 15 and then released into the atmosphere, the exhaust gas of the combustor 21 can be purified without newly providing a catalyst or a muffler for the combustor 21. it can.

When the engine 10 is operating,
Since the exhaust gas of the combustor 21 is discharged through the second exhaust duct 29 into the intake pipe 11 of the engine 10, the exhaust gas of the engine 10 is supplied to the combustor 21 without using a volume (volume) type blower. Backflow can be prevented, and the combustor 21 can be stably burned. Therefore, it is possible to stably burn the combustor 21 while suppressing an increase in the manufacturing cost of the vehicle heating device.

Further, since the exhaust gas of the combustor 21 can be purified without newly providing a catalyst or a muffler for the combustor 21, the mountability of the vehicle heating device having the combustor 21 on a vehicle is improved. Can be done. Further, since the exhaust gas of the combustor 21 is also discharged into the atmosphere via the exhaust pipe 13 of the vehicle, the layout of the exhaust system of the combustor 21 can be simplified, and the mountability of the combustor 21 in the vehicle is improved. Can be done.

When the engine 10 is stopped,
Since the cooling water heated by the combustor 21 circulates through the heater core 20 and the engine 10, the engine 10 is warmed (warmed up) in addition to the vehicle interior, so that the engine 10 is warmed up at the next engine start. Machine operation time can be reduced. Further, when the engine 10 is stopped, the exhaust gas of the combustor 21 is guided to the catalyst 14, so that
The temperature of the catalyst 14 can be increased. Therefore, at the time of the next engine start, the time required for raising the temperature of the catalyst 14 to a predetermined temperature (activating the catalyst 14) can be shortened, so that the exhaust gas of the engine 10 can be quickly purified. .

When the engine 10 is operating,
Since the exhaust gas of the combustor 21 is guided to the intake pipe 11 of the engine 10, it is possible to suppress the emission of nitrogen oxides from the engine 10 as in the exhaust gas recirculation device. Further, in the combustor 21, the fuel burns more slowly than the engine 10, so that the fuel easily burns completely.
The exhaust gas has a smaller amount of oxygen than the exhaust gas of the engine 10. For this reason, the engine 1 is oxidized (combusted) by the oxygen in the exhaust as compared with a so-called ordinary exhaust gas recirculation system that recirculates the exhaust of the engine 10 to the intake side of the engine 10.
0 can be suppressed from rising in the combustion chamber temperature. Therefore, nitrogen oxides can be reduced more reliably and reliably than in a normal exhaust gas recirculation device.

(Second Embodiment) This embodiment relates to a combustion machine 2
1 is intended to improve the ignitability (startability). That is, in the present embodiment, as shown in FIG. 3, the cooling water flowing out of the engine 10 is connected to the suction port side of the electric water pump 23 and the outlet side of the combustor 21 by the bypass passage 25, and A signal for igniting (operating) the combustor 21 (hereinafter, this signal is referred to as an ignition signal) while allowing the pump 23 and the combustor 21 to be bypassed and guided to the inflow side of the heater core 20 is provided. The electric water pump 23 is stopped until a predetermined time elapses from the time of the emission, and thereafter, the electric water pump 23 is stopped.
Is running.

This makes it possible to prevent the cooling water from circulating in the combustor 21 at the same time that the ignition signal is issued to the combustor 21, so that the heat in the combustor 21 is reduced before the combustor 21 is completely ignited. Outflow to the outside (heater core 20) side can be suppressed. Therefore, the ignitability of the combustor 21 can be improved. By the way, in the above-described embodiment, the discharge destination of the exhaust of the combustor 21 is switched by using the electric switching valve 30 in which the valve body is moved by the stepping motor. However, the present invention is not limited to this. Alternatively, the valve body may be moved via an actuator that moves by the negative pressure of a vacuum pump (vacuum pump) that operates in conjunction with the engine 10.

In this case, as shown in FIG. 4, in the exhaust gas recirculation device, the vacuum pump
Exhaust recirculation pipe 31 connecting exhaust pipe 13 and intake pipe 11
It is also desirable to double as a vacuum pump 33 that operates an EGR valve 32 that opens and closes the valve. Also, Engine 1
Mechanical switching valve 3 that directly operates the actuator to operate the valve body by utilizing the differential pressure between the exhaust pressure and the suction pressure of 0
It may be set to 0.

In the above-described embodiment, the heat of the combustor 21 is given to the cooling water to heat the vehicle interior. However, the vehicle interior may be directly heated and heated by the combustor 21. Further, the vehicle heating device according to the present invention is not limited to a diesel engine for a vehicle, but can be applied to a gasoline engine. Further, the vehicle heating device according to the present invention,
The engine 10 uses the energy of the exhaust of the engine 10
It can also be applied to turbocharged engines that supercharge the intake air.

In this case, both the intake side and the exhaust side of the combustor 21 are connected to the intake flow upstream or downstream from the turbocharger to reduce the pressure difference between the intake side and the exhaust side of the combustor 21. There is a need to. If there is a turbocharger or a throttle valve between the intake side and the exhaust side of the combustor 21, the turbocharger is stopped or the throttle valve is opened while the combustor 21 is in operation to open the combustor 21. It is necessary to reduce the pressure difference between the intake side and the exhaust side of 21.

Further, in the case where an intercooler for cooling the intake air is provided in the intake pipe 11 of the engine 10, the exhaust of the combustor 21 is discharged to the intake pipe 11 upstream of the intercooler in the intake pipe 11. In this case, it is desirable to provide a drain port for discharging condensed water in the intercooler. This is because the exhaust gas of the combustor 21 contains a large amount of water vapor, and condensed water is generated when the exhaust gas of the combustor 21 is cooled by the intercooler.

In the above-described embodiment, whether the engine 10 is operating is determined based on the ignition signal, or based on a signal from an alternator (generator) that operates in mechanical cooperation with the engine 10. Alternatively, it may be determined whether the engine 10 is operating.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a vehicle heating device according to a first embodiment.

FIG. 2 is a flowchart showing a control flow of an ECU.

FIG. 3 is a schematic diagram of a vehicle heating device according to a second embodiment.

FIG. 4 is a schematic diagram of a vehicle heating device according to a modification of the present invention.

[Explanation of symbols]

Reference Signs List 10: water-cooled engine (liquid-cooled engine), 11: intake pipe, 12: air cleaner, 13: exhaust pipe, 14: three-way catalyst, 15: muffler, 20: heater core (heating means),
21: combustor, 28: first exhaust duct (first exhaust pipe),
29: second exhaust pipe, 30: switching valve.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-63-71409 (JP, A) JP-A-63-71413 (JP, A) JP-A-63-71572 (JP, A) JP-A-61-71 54313 (JP, A) Japanese Utility Model Showa 57-67813 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60H 1/03 B60H 1/22

Claims (1)

(57) [Claims] An exhaust pipe (13) for discharging exhaust gas from an internal combustion engine (10) into the atmosphere, a catalyst (14) for purifying exhaust gas guided through the exhaust pipe (13 ), and exhaust gas. A vehicle heating device applied to a vehicle having a muffler (15) for reducing noise, a heating unit (20) for heating a vehicle interior using waste heat of the internal combustion engine (10) as a heat source, and burning fuel. Combustor (2)
1), and when the internal combustion engine (10) is stopped, the combustion machine (2)
The exhaust gas of (1) is passed through the catalyst (1) in the exhaust pipe (13).
4) and discharge to the upstream side of the muffler (15).
The exhaust path of the combustor (21) is switched during the operation of the internal combustion engine (10).
To the intake side of the internal combustion engine (10).
An OFF signal for switching the exhaust path of the combustor (21) and stopping the combustor (21) was generated.
At times, the exhaust of the combustor is absorbed by the internal combustion engine (10).
The exhaust path of the combustor (21) is discharged to the air side.
A vehicle heating device characterized by switching .