JPS6371412A - Heating device for vehicle - Google Patents

Abstract

PURPOSE:To enable the intake pipe of an engine directly take in a combustion gas and improve the assisting function of engine starting by feeding a combustion gas obtained by the combustor of a heater into said intake pipe or the heat exchanger of said heater through a selector valve. CONSTITUTION:A combustion gas passage 39 which is branched off from the combustion gas passage 20 in between a combustor 5 and a heat exchanger 8 is connected to the intake pipe 3 of an engine 1. And, a selector valve 40 is provided on the branched part of the combustion gas passage pipes 20, 39. Also, a check valve 18 is provided on the combustion gas passage 39. Thereby, a combustion gas obtained by the combustor 5 is fed into the intake pipe 3 of the engine 1 through the combustion gas passage 39 without being fed into the heat exchanger 8. This circuit is used when starting the engine at a cold time or at the time of warming up. On the other hand, the combustion gas passage 39 is closed by the selector valve 40 at the time of ordinary heating. Accordingly, the assisting function of starting the engine 1 and a warming-up function can be improved while enabling the rapid heating of a vehicle room.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vehicle heating system that uses exhaust gas, ie, combustion gas, generated in a combustor in a heater to assist in starting an engine.

[Conventional technology]

Conventionally, as a vehicle heating system, Japanese Patent Application Laid-Open No. 60-2520
18, Utility Model Application Publication No. 6159876, etc. are disclosed.

What is described in Japanese Unexamined Patent Publication No. 60-252018 will be summarized with reference to FIG. The automobile heating system shown in FIG. 4 includes a burner device 104 for burning fuel in an intake pipe 103 of an engine 101, and
A heat exchanger 105 is provided downstream of the burner device 10
The heat generated by burning the fuel in step 4 is recovered by the heat exchanger 105, and the recovered heat is used as a heat source for heating.

What is described in Utility Model Application Publication No. 61-59876 is the 5th
An overview will be given with reference to the figure. The engine warm-up device shown in FIG.
and an intake pipe 3 which sequentially arranges a heat exchanger 8 connected to a heater unit 9 of the vehicle and further bypasses the intake detour 4.
A pressure regulating valve 12 is provided. The combustor 5 is connected to a fuel injection pump 10 attached to the engine 1 via a fuel vibro, and combusts fuel from a fuel tank 11 in the intake detour 4. Regarding heat exchanger 8,
The air outlet side is connected to the heater unit 9 of the vehicle, and the warm air heat-exchanged by the combustion gas of the burner, that is, the vaporizer 7 is configured to flow into the heater unit 9. A check valve I5 such as a reed valve is installed downstream of the heat exchanger 8 in the intake detour 4 and upstream of the junction of the intake detour 4 with the intake pipe 3. intake detour 4
be configured to prevent intrusion from the downstream side. A pressure regulating valve 12 is installed in a portion of the intake pipe 3 that bypasses the intake detour 4. This pressure regulating valve 12 is connected to the intake pipe 3 before and after the pressure regulating valve 12.
The pressure regulating valve 12 has an arm 12b attached to its rotating shaft 12a, and this arm 12b is attached to a rod protruding from a diaphragm 13a of a diaphragm type actuator 13. 13e
is in contact with. The spring chamber 13b of the actuator 13 is connected to the intake pipe 3 on the downstream side of the pressure regulating valve 12 through a communication pipe 13d.
The spring chamber 13b is connected to a negative pressure sensor 14 installed in the spring chamber 13b so that the pressure on the downstream side of the pressure regulating valve 12 is introduced into the spring chamber 13b.

This engine warm-up device configured as described above operates as follows. Immediately after a cold start of the engine 1, the intake air flows through the intake detour 4 due to the action of the pressure regulating valve 12, so at this time, the vaporizer 7 of the combustor 5 is ignited to heat the intake air. The thus heated intake air warms the room heating air in the heat exchanger 8, and is introduced into the engine l from the intake manifold 2 to improve the warm-up performance of the engine l.

In this state, the pressure regulating valve 12 is driven by the actuator 13 according to the pressure detected by the negative pressure sensor 14. That is,
When the pressure downstream of the pressure regulating valve 12 is low, the spring chamber 13b
As the internal pressure decreases, the diaphragm 13a swells toward the spring chamber 13b, causing the rod 13C to move toward the actuator 13.
When the pressure on the downstream side of the pressure regulating valve 12 increases, conversely, when the pressure on the downstream side of the pressure regulating valve 12 increases, the pressure on the downstream side of the pressure regulating valve 12 increases. Since the pressure inside the chamber 13b increases, the diaphragm 13
a expands to the opposite side of the spring chamber 13b and pushes out the rod 13c from inside the actuator 13, and the pressure regulating valve 12 is slightly closed to reduce the amount of intake air flowing through the intake pipe 3.
This lowers the pressure downstream of the Due to the above operation of the pressure regulating valve 12, the pressure difference between the inlet and outlet of the intake detour 4 is always maintained constant, so that the combustor 5 is not affected by changes in the amount of intake air due to changes in engine rotation. The burner composed of the vaporizer 7 burns stably without blowing out. In addition, by providing the check valve 15 near the confluence with the intake pipe 3 on the outlet side of the intake detour 4, the engine
The backflow of intake air due to bank fire and intake pulsation does not cross the check valve 15 and flow back into the intake bypass path 4.

Therefore, the flame of the burner burns stably without being blown out, making it possible to improve the warm-up performance of the engine 1 and achieve rapid room heating.

[Problem that the invention seeks to solve]

However, in the automotive heating system and engine warm-up system shown in Figures 4 and 5, the combustion gas is introduced into the engine intake pipe after passing through a heat exchanger, and if the heat exchanger function is not Even if the engine is stopped, the combustion gas passes through the heat exchanger and is sucked into the engine due to its heat capacity, resulting in a lower rate of increase in air temperature. Therefore, there is a problem in that the effectiveness as a starting aid is reduced by half.

The purpose of this invention is to improve the starting assist function and warm-up function of the engine by directly drawing the combustion gas generated in the combustor of the heater into the engine intake pipe in order to maintain the hot state as much as possible. To provide a vehicle heating device capable of rapidly heating the inside of a vehicle after starting.

[Means for solving problems]

The present invention is configured as follows in order to solve the above problems and achieve the second object.

That is, the present invention relates to a heating device for a vehicle characterized in that combustion scum generated in a combustor of a heater is controlled to be sent to an intake pipe of an engine or a heat exchanger of the heater using a switching valve, and further Specifically, the combustion air for the combustor is configured to be taken in from the 047 intake pipe of the engine, and extends from between the combustor and the heat exchanger and is connected to the intake pipe. A check valve is provided in the combustion gas passage of the heat exchanger, and a check valve is provided in the combustion gas passage that communicates the F-flow combustion gas passage of the heat exchanger with the intake pipe. Vehicle heating, characterized in that the switching valve is switched to connect to the intake pipe when warming up the engine, and after the engine is warmed up, the switching valve is switched to connect to the heat exchanger. Regarding equipment.

[Effect]

The vehicle heating system according to the present invention is constructed as follows, and operates as follows. That is, this invention:
Since the combustion gas generated in the combustor of the heater was controlled to be sent to the intake pipe of the engine or the heat exchanger of the heater using the switching valve, the combustion gas of the combustor was controlled to flow before starting or warming up the engine. can be sent directly to the intake pipe of the engine without passing through the heat exchanger,
The engine can be assisted in starting and warmed up at a high temperature without lowering the temperature of the combustion gas. Further, since the combustion air for the combustor is taken in from the intake pipe of the engine, the air cleaner can be used in common as the air cleaner for the engine and the air cleaner for the combustor. Furthermore, since a check valve is provided in the combustion gas passage of the heater, backflow from the intake pipe can be prevented. Further, when the engine is started and warmed up, the switching valve is switched to communicate with the intake pipe, and after the engine is warmed up, the switching valve is switched to communicate with the heat exchanger. Immediately after starting the engine, the heater can function to its fullest.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle heating device according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a basic schematic diagram of a vehicle heating system which is an embodiment of the present invention.

This vehicle heating system is compared with the engine warm-up system described with reference to FIG. 5, where parts with the same configuration are given the same reference numerals, explanations thereof are omitted, and differences will be explained. do. A combustion gas passage 39 branched from the combustion gas passage 2o between the combustor 5 and the heat exchanger 8 is connected to the intake pipe 3 of the engine 1. A switching valve 40 is provided at a branch portion between the combustion gas passage 20 and the combustion gas passage 39.

In addition, a check valve 1 such as a reed valve is provided in the combustion gas passage 39.
8 is provided. In the figure, A indicates the flow direction of combustion air, B indicates the flow direction of combustion gas, F indicates the flow direction of fuel, and H indicates the flow direction of heating air in the vehicle.

FIG. 2 shows an example in which the vehicle heating device according to the present invention is applied to a vehicle together with its control device, in which a rapid heating device QH3 is installed as a heater. The rapid heating device QH3 is capable of rapidly heating a room by using a combustor and a heat exchanger, which will be described later. Regarding the rapid heating device QH3, the combustor 5 is configured to vaporize the liquid fuel using the vaporizer 7 to generate vaporized fuel, combust the vaporized fuel, and send the combustion gas to the heat exchanger 8. . In this case, combustion air for the combustor 5 is not introduced from the intake pipe 3 of the engine 1, but is taken from an air cleaner 23 provided separately. An air cleaner 24 is provided upstream of the intake pipe 3 of the engine l.
is provided. In addition, in order to achieve the same function as the vehicle heating system shown in FIG. Close. A combustion gas passage 39 branched from a combustion gas passage 41 between the combustor 5 and the heat exchanger 8 is connected to the intake pipe 3 of the engine 1. A switching valve 40 is provided at a branch point between the combustion gas passage 39 and the intake pipe 3.

In addition, in the figure, 42 is an engine intake instruction switch that manually instructs whether to send exhaust gas, that is, combustion gas generated by the heater, to the intake pipe 3 of the engine 1, 43 is an activation switch for the rapid heating device QH3, 44 is an operation switch for keeping the engine warm, which manually sends combustion gas to the outer surface of the engine 1, that is, the cylinder block, oil pan, etc. in order to keep the engine 1 warm; 45, 47 is a temperature sensor; and 46 is a switch for noise reduction. valve; 50 is a main control device; 70 is an exhaust brake activation switch for inputting exhaust brake activation; 7
1 is an air tank that stores air compressed by the engine 1, etc., 72 is a timer set by the user, 73 is a thalassotion/off signal sensor that inputs clutch on/off signals, and 74 is a sensor that indicates whether the accelerator is free or slightly An accelerator signal sensor that emits a signal as to whether the pedal is depressed, 75 is a starter, 76 is a key switch such as an engine starter installed in the driver's seat, 77 is a silencer,
Reference numeral 78 indicates a switching valve for the exhaust brake that manually operates the exhaust brake, 79 indicates a temperature sensor that detects the temperature of heating air sent into the cab, and 80 indicates a battery.

Next, although the details of the combustor 5 and the heat exchanger 8 are not shown, it is preferable to use one having the following configuration, for example. Examples of these will be explained in detail with reference to FIG.

First, the heat exchanger 8 will be explained. A blower 36 is installed upstream of the heat exchanger 8 through an air intake pipe. A suction duct 37 serving as a circulating air intake passage is attached to the suction port of the blower 36 . The suction duct 37 is configured to introduce heating air from the interior 28 of the vehicle or from outside the vehicle, and may be configured to gradually become narrower toward the downstream, or may be a simple circulation pipe. Although not shown, the heat exchanger 8 has a structure in which a heat absorption passage cylinder is arranged around the outer periphery of a heat flow passage cylinder, which is a double cylinder. The heat flow passage cylinder includes a heat flow outward passage cylinder and a heat flow return passage cylinder disposed around the outer circumference thereof. A combustor 5 is attached to one end of the heat flow outgoing cylinder. Therefore,
The heat exchanger 8 has a heat flow path in the center through which combustion gas from the combustor 5 passes, a heat transfer path in the middle to transfer the combustion heat of the combustion gas to the outer circumferential side, and an outer portion to radiate the combustion heat and generate cold air. It consists of an endothermic passage that converts heat into hot air. Moreover, the heat flow passage, the heat transfer passage, and the heat absorption passage are arranged coaxially with each other. The heat absorption passage cylinder constitutes an outer case of the heat exchanger 8, and is covered with a heat insulating material or the like. Both ends of the outer case have an air intake pipe 2 at one end.
A bent pipe is attached to one end and the other end, and the bent pipe is connected to a hot air blowing duct 22. A cup-shaped lid with fins is fixed to the end of the heat flow return path cylinder. With this structure, the flow path for combustion gas, that is, the heat flow path and the heat transfer path, and the flow path for air, which undergoes heat exchange and is used for heating, or the heat absorption path are completely cut off.

Further, the other end of the heat flow outward passage cylinder and one end of the heat flow return passage cylinder are in communication with each other, and the other end of the heat flow return passage cylinder is provided with an exhaust pipe having a combustion gas outlet, that is, a combustion gas exhaust pipe. aisle 16
is installed. This combustion gas is configured to be sent into the intake pipe 3 of the engine. Further, a large number of heat receiving fins are arranged on the heat flow return path cylinder.

Further, a large number of heat radiation fins are arranged in the heat absorption passage cylinder. From the viewpoint of heat conduction, it is preferable that the heat receiving fins and the heat dissipating fins are provided integrally with the heat flow outgoing cylinder. In other words, heat receiving fins are formed inside the heat flow return path cylinder, and heat radiation fins are formed outside the heat flow return path cylinder.

Next, the combustor 5 will be explained. The combustor 5 consists of a combustion tube, the combustion tube is divided into a vaporization chamber and a combustion chamber by a partition plate having a communication hole, and a vaporization device 7 having a built-in glow plug 30 for vaporization is arranged to penetrate the combustion chamber. , an ejection port for ejecting the vaporized fuel vaporized by the vaporization device 7 is opened in the vaporization chamber; furthermore, an ignition glow plug 29 is installed in the vaporization chamber. The vaporizing glow plug 30 vaporizes the liquid fuel into vaporized fuel, and
A glow plug 2 that takes in combustion air to generate vaporized fuel and a mixture, and ignites the slight amount of oil droplets or mixture.
9, the air-fuel mixture is ignited in the combustion chamber. By using such a combustor 3,
The liquid fuel rapidly vaporizes to a vaporized fuel, and the vaporized fuel is rapidly ignited or ignited, allowing rapid combustion. As a result, the combustor 5 can immediately send combustion gas to the heat exchanger 8, so that the function of the heat exchanger 8 can be quickly performed, and the combustor 5 can be used for heating.

The vehicle heating system according to the present invention is constructed as described above and operates as follows. Regarding the operation of this vehicle heating system, first, basic operating conditions will be explained. In FIG.
9 into the intake pipe 3 of the engine 1 so that it is directly inhaled into the engine 1. When using this circuit,
This is the time to assist in starting the engine 1 in cold weather or to perform warm-up operation. During normal heating operation, the switching valve 40
is at the position indicated by the solid line, and the combustion gas passage 39 is closed. The condition for the switching valve 40 to be in the dotted line position, the combustion gas passage 39 to be opened, and the bypass circuit to be activated is when the cooling water temperature of the engine 1 is below a specified value, for example, about 5°C; This is when the vehicle heating system including the engine 1 is set in the starting circuit. When only the heater operates independently and the engine 1 is started, there is no need to operate the bypass circuit.

Next, the operation of the Nyorori one-car heating system of the present invention equipped with the heater of the rapid heating system QH8 shown in FIG. 2 will be explained. Furthermore, the flowchart shown in Figure 3 (・
The processing status of the operation of the vehicle heating system will be explained with reference to .

First, start the vehicle heating system.

---(,51) Determine whether the operation switch 43 of the rapid heating device QH5 consisting of the combustor 5 and the heat exchanger 8 is on. When the operation switch 43 of the rapid heating device QH3 is on, the process proceeds to the next step (53), and when it is not on, the process returns to the previous step.
----------- (52) When the operation switch 43 of the rapid heating device QH5 is on, the ignition plug 1 - the plug 2
9. Electrify the vaporizing glow plug 30.

11--(53) The liquid fuel pump 32 is operated to send liquid fuel from the liquid fuel tank 11 to the vaporizer 7. By operating these, liquid fuel is supplied to the combustor 3 and converted into vaporized fuel.

The blower 31 is operated to send combustion air to the combustor 5. The combustor 5 vaporizes the liquid twister 4 to generate vaporized fuel, and enters a combustion state.

The temperature of the combustion gas is detected by a temperature sensor 34 installed at the combustion gas outlet of the heat exchanger 8, that is, at the combustion gas passage 1G. For example, if the temperature is above about 200°C, the process proceeds to the next step (57), and if it is below about 200°C, various control devices are adjusted and the combustion operation of the combustor 5 is continued.

It is determined whether the engine intake instruction switch 42, which causes combustion gas to be sucked into the engine 1 to assist in starting or warm up the engine 1, is on.

The following process (58
). However, when combustion gas is not sent to the intake pipe 3 of the engine 1, any one of the engine intake switching valve 25, the 9J switching valve 26 for engine heat retention, and the atmospheric release switching valve 27 is opened, A switching valve 40 installed in the combustion gas passage 39 is closed to prevent combustion gas from being sent to assist in starting or warming up the engine I. However, when engine 1 is running,
Of course, in order to completely burn the combustion gas, the engine intake switching valve 25 may be opened to send the combustion gas into the intake pipe 3 of the engine 1.
(57) The rotational speed of the engine l is detected by the rotation sensor 35. It is determined whether the rotation speed of the engine 1 is a predetermined value, for example, 800 rpm or more.

If the rotation speed of engine 1 is below the predetermined value, the next process (5
Proceeding to step 9), if the value is greater than or equal to the predetermined value, it means that the starting assistance or warming-up operation of the engine 1 is not necessary, and the starting assistance or warming-up operation of the engine 1 is ended.
(5B) If the rotational speed of the engine 1 is below a predetermined value, the engine 1 is assisted in starting or warmed up. In that case, the switching valve 25 for engine intake, the switching valve 26 for engine heat retention, and the switching valve 27 for venting to atmosphere are closed, the switching valve 40 of the combustion gas passage 39 is opened, and the combustion gas is transferred to the heat exchanger. 8 directly into the intake pipe 3 of the engine 1.
-1---(59) The driver starts the engine 1.
-, , (60) Determine whether the rotational speed of the engine I is equal to or higher than a predetermined rotational speed, for example, about 80 rpm. If the rotational speed of the engine 1 is equal to or lower than the predetermined rotational speed, the engine 1 is assisted in starting or warmed up, and the starting operation is performed again. If the rotation speed of the engine 1 is equal to or higher than the predetermined rotation speed, the process proceeds to the next process (62).

-------1-----, -(61) If the rotation speed of the engine 1 is equal to or higher than a predetermined rotation speed, the switching valve 40 of the combustion gas passage 39 is closed, and engine starting assistance or warm-up operation is stopped. do. At this time, the rapid heating device QH
3, selector valve 2 for engine intake
5. Open either the engine heat retention switching valve 26 or the atmospheric release switching valve 27, close the switching valve 40, and send combustion gas to the engine 1 to assist in starting or warming up the engine 1. Try not to let it get in the way. but,
Of course, the combustion gas may be sent into the intake pipe 3 of the engine 1 by opening the engine intake switching valve 25 in order to completely burn the combustion gas.
-------------(62") The startup assistance or warm-up operation of engine 1 by the rapid heating device QH3 ends. ---------------------- (63) In addition, when the rapid heating device QH3 is operated, for example, when the above-mentioned combustor 5 and heat exchanger 8 are used, the operation will be as follows.The combustion gas generated by the combustor 5 is The combustion gas is blown into the heat flow passage in the outward heat flow cylinder.The combustion gas blown into the heat flow passage is guided by the lid body from the heat flow passage in the heat flow outward cylinder, makes a U-turn, and flows through the heat transfer passage in the heat flow return cylinder. Since a large number of heat receiving fins are installed in the heat transfer passage in the radial direction, the combustion gas is deprived of combustion heat by the heat receiving fins, and is finally discharged from the combustion gas outlet to the combustion gas passage 16. , the heated air is passed through the suction duct 3 by the blower 36.
7 and is blown into the heat absorption passage cylinder of the heat exchanger 8 through the air intake port 21 of the blower 36, that is, the scroll outlet 21. The sent air flows between heat radiation fins installed in the heat absorption passage. In the heat absorption passage, a large number of radial heat dissipation fins are fixedly disposed on the outer periphery of the heat flow return path cylinder, and air passes between the heat dissipation fins and absorbs combustion heat from the heat flow fins. It can be warmed up. The warmed air becomes hot air, and then passes through a large number of radiating fins provided in the radial direction around the outer circumference of the lid body to be further warmed and flows. Next, the heated air passes through the hot air blowing duct 22 and is blown out from the hot air blowing outlet 38 into the vehicle interior 28. The hot air keeps the inside of the car warm, and then passes through the filter at the air intake port to the suction duct 37 and is sent to the blower 3.
It is sucked in by the action of 6. The sucked air is sent from the scroll outlet 21 of the blower 36 to the heat exchanger 8 again through the air intake pipe. The above operation is repeated to keep the interior of the vehicle at a predetermined temperature.

Although one embodiment of the vehicle heating device according to the present invention has been described in detail, the present invention is not limited to the detailed structure described above. That is, it goes without saying that various configurations can be applied to the combustor and heat exchanger. For example, the combustor may be of any type as long as it uses a glow plug, which is a heating plug, to vaporize liquid fuel into vaporized fuel and ignite it, and a vertical type, horizontal type, etc. can be applied. The design of the heat exchanger can also be changed in various shapes and structures, as well as in the shape and structure of the fins incorporated therein.

〔Effect of the invention〕

Since the vehicle heating device according to the present invention is configured as described above, it has the following effects.

That is, in this invention, the combustion gas generated in the combustor of the heater that operates independently of the engine is controlled to be sent to the intake pipe of the engine or the heat exchanger of the heater using the switching valve. Before starting the engine, the combustion gas of the combustor can be directly sent to the intake pipe of the engine without passing through the heat exchanger, and can be used to assist or warm up the engine without lowering the temperature of the combustion gas. Machine functions can be improved. Moreover, it has a simple structure in which the combustion gas passage of the combustor and the intake pipe of the engine are connected through a combustion gas passage and a switching valve is installed there.Furthermore, the operation itself is extremely simple, and there is no problem with malfunctions. The combustion gas generated in the combustor is sent to the engine or to the exhaust pipe of the engine, which is extremely preferable in terms of safety. Further, when the combustion air for the combustor is taken in from the intake pipe of the engine, the air cleaner can be used in common as the air cleaner of the engine and the air cleaner of the combustor. Furthermore, since a check valve is provided in the combustion gas passage, backflow from the intake pipe can be prevented. Further, when the engine is assisted in starting or warmed up, the switching valve is switched to communicate with the intake pipe, and after the engine is warmed up, the switching valve is switched to communicate with the heat exchanger. Immediately after starting the engine, the heater can be put into full operation for heating the vehicle.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a basic device of a vehicle heating device according to the present invention, FIG. 2 is a schematic diagram showing an embodiment of a vehicle heating device according to the present invention, and FIG. 3 is a schematic diagram showing a basic device of a vehicle heating device according to the present invention. Flowchart explaining the operating state of the heating device, No. 4
This figure is a schematic diagram showing a conventional vehicle heating system, and FIG. 5 is a schematic diagram showing a conventional engine warm-up system. l engine, 3- intake pipe, 5-- m- combustor,
7----vaporizer, 8----・heat exchanger, 11-m
- liquid fuel tank, 16. 39. 41 --- one combustion gas passage, 23, 24 --- one air cleaner, 25
, 26, 27゜40---Switching valve, 28--Vehicle interior, 29-1 Ignition globe lug, 3 (1-Ignition globe lug, 31, 36--Blower, 34-11 Temperature Sensor, 35----One rotation sensor, 50-
-----Main controller.

Claims (7)

[Claims] (1) A heating device for a vehicle, characterized in that combustion gas generated in a combustor of a heater is controlled to be sent to an intake pipe of an engine or a heat exchanger of the heater using a switching valve. (2) The heating device for a vehicle according to claim 1, characterized in that the combustion air for the combustor is taken in from the intake pipe of the engine. (3) A check valve is provided in a combustion gas passage extending from between the combustor and the heat exchanger and connected to the intake pipe. Vehicle heating system. (4) The vehicle heating device according to claim 1, wherein a combustion gas passage downstream of the heat exchanger is connected to the intake pipe. (5) The vehicle heating device according to claim 1, wherein a check valve is provided in the combustion gas passage downstream of the heat exchanger. (6) The vehicle heating device according to claim 1, wherein the switching valve is switched to communicate with the intake pipe when the engine is started and warmed up. (7) The vehicle heating system according to claim 1, wherein the switching valve is switched to communicate with the heat exchanger after the engine is warmed up.