JP3899470B2 - Vehicle heating system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle heating device that is mounted on a vehicle and uses engine coolant as a heat source, and more particularly, to a device that includes a mechanism that supplementarily heats engine coolant.
[0002]
[Prior art]
In recent years, with the adoption of DI (direct injection) method and lean burn system in diesel engines and gasoline engines, the efficiency of the engine is being improved. The efficiency of such an engine increases the temperature of the engine coolant. In the vehicle air conditioner provided with the hot water heat exchanger using the engine coolant as a heat source, there is a problem that the heating capacity is lowered.
[0003]
Moreover, even if the engine is turned off when the vehicle is stopped, such as a hybrid car (a car that generates electricity with an engine and runs with electricity), which is expected to increase in the future, there is a concern that the heating capacity of the hot water heat exchanger will be reduced. Is done.
[0004]
As means for solving these problems, use of techniques as disclosed in Japanese Utility Model Laid-Open No. 62-59771 and Japanese Patent Laid-Open No. 1-289713 can be considered. In the former, an electric heater is inserted into the pipe in the middle of the pipe through which the engine cooling water flows, and the cooling water flowing in the pipe is heated by energizing the electric heater. Similarly, an electric heater is installed in the cooling water, and an electric heater is also arranged in the ventilation duct of the air conditioner.
[0005]
[Problems to be solved by the invention]
However, in the configuration in which the electric heater is directly installed in the flow path of the cooling water, a sufficient sealing structure is required at the installation location of the electric heater so that there is no leakage of the cooling water, and the electric heater is placed in the cooling water. Because it is arranged, there is a safety problem. Even in the configuration where the electric heater is arranged in the ventilation path, there is a risk that foreign matter entering the ventilation path may adhere to the electric heater and short-circuit the electric system of the electric heater. There's a problem.
[0006]
Therefore, in the present invention, in the heating device using the engine cooling water as a heat source, the electric heater is used as an auxiliary heat source for heating the engine cooling water. An object of the present invention is to provide a vehicle heating device that sufficiently secures the above.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, an auxiliary heating device is provided in the middle of a path for circulating the cooling water to the hot water heat exchanger as a heating device for auxiliary heating of the cooling water in the cooling water path. A heat storage unit that enables the passage of cooling water, an auxiliary circulation path that circulates cooling water separately from the path, and a circulation pump that is interposed in the middle of the auxiliary circulation path. It is comprised by the at least 2 pipe material which intervenes in the middle of an auxiliary | assistant circulation path, and distribute | circulates cooling water, and the electric heater pinched | interposed by these pipe materials (Claim 1 ).
[0008]
In such a configuration, since the cooling water inside the heat storage unit can be heated by the auxiliary heating device provided in the circulation path, the heat storage unit can be stored by the auxiliary heating device, and hot water heat exchange with the internal combustion engine is possible. The cooling water that circulates between the heat generators can be immediately heated by the heat stored in the heat storage unit.
[0009]
As an attachment mode of the auxiliary heating device, the auxiliary environment path is formed in a U-bent shape, thereby creating a portion where the upstream paths are close to each other and facing each other, and two pipe members are connected to each of the opposed upstream paths. (Claim 3 ), a branch path is formed by branching the cooling water into the auxiliary circulation path and flowing it in parallel, and then joining them again , so that two pipes are connected to each of the parallel branch paths. It may be made to intervene in the middle (claim 4 ).
[0010]
Here, the electric heater is also possible to use a ceramic heater, and the number with multiple sandwiched by tubing may be switched to the number of the electric heater to be energized in response to the coolant temperature (claim 2,5 ).
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a heating device used for a vehicle equipped with an engine 1 is shown. This heating device has an air conditioning duct 6 constituting an air conditioning passage 5 arranged in a vehicle compartment 4 separated from the engine compartment 2 by a partition wall 3. The air-conditioning duct 6 includes at least a blower 7 that sucks air (outside air or inside air) and a heater core 8, and supplies cooling water for the engine 1 to the heater core 8.
[0012]
The cooling water of the engine 1 flows through a water jacket 10 provided around the combustion chamber of the engine 1, and the cooling water warmed here is sent to the radiator 12 by driving the water pump 11, where the radiator fan 13 The air is exchanged with the air sent from, and then returned to the water jacket 10.
[0013]
Further, a thermostat 14 for adjusting the temperature of the cooling water is provided on the path circulating between the water jacket 10 and the radiator 12, and when the cooling water temperature at the initial stage of the engine start is low, the thermostat 14 is connected to the radiator 12. The circulation of the cooling water is stopped so that the rapid increase of the cooling water temperature is not hindered.
[0014]
The cooling water in the water jacket 10 is also circulated to the heater core 8 via the pipes 15 and 16. The pipes 15 and 16 are drawn from the heater core 8 to the engine room 2 through the air conditioning duct 6 and the partition wall 3, and the pipe 15 constituting the path upstream of the heater core 8 is connected to the water jacket 10 and is more than the heater core. The pipe 16 constituting the downstream path is connected to the upstream side of the water pump 11. By driving the water pump 11, the cooling water in the water jacket 10 is sent to the heater core 8, where it is cooled by exchanging heat with the air sent by the blower 7 in the air conditioning duct 6, and then passed through the water pump 11. And returned to the water jacket 10.
[0015]
An auxiliary heating device 17 is provided in the middle of the pipe 15 constituting the path upstream of the heater core 8. This auxiliary heating device 17 forms part of the path in a U-bent shape to form a path part that is close in parallel, and as shown in FIGS. 2 and 3, the first and second two pipe members 18 and 19 and first and second ceramic heaters 20 and 21 sandwiched between the pipe members 18 and 19.
[0016]
One end opening of the first pipe 18 is connected to the pipe 22 connected to the water jacket 10, and one end opening of the second pipe 19 is connected to the pipe 23 connected to the heater core 8. The other end openings of the pipes 18 and 19 are connected to the U-shaped pipe 24, and therefore the pipe 15 constituting the path upstream of the heater core 8 includes the pipe 22, the first pipe 18, and the U-shape. The tube 24, the second tube material 19, and the tube material 23 are configured.
[0017]
The first and second pipe members 18 and 19 are obtained by integrating the metal tubes 18b and 19b with the metal blocks 18a and 19a formed with flat portions extending in parallel with the axis so as to be parallel to the plane portion. The metal tubes 18b and 19b formed in advance are put into a mold, and the metal blocks 18a and 19a are integrally die-cast around the metal tubes 18b and 19b. The flat portions 18c and 19c of the metal blocks 18a and 19a are formed so that the side edges protrude in a flange shape, and this protruding portion is used as a fixing allowance for fixing the pipe members together.
[0018]
The first and second pipe members 18 and 19 have the same shape, and are fixed by sandwiching the ceramic heaters 20 and 21 by the flat portions 18c and 19c of each other, for example, by sandwiching the fixing margin with the clip 25. . The means for fixing the first and second pipe members 18 and 19 is not limited to such a method, and a through hole is formed in the fixing margin of the metal blocks 18a and 19a, and a through bolt is inserted into the through hole. You may make it fix both pipe materials by making it mount | wear.
[0019]
The first and second ceramic heaters 20 and 21 are juxtaposed in the longitudinal direction (the axial direction of the metal tube) of the flat portions 18c and 19c of the first and second tube members 18 and 19, respectively. As shown in Japanese Patent No. 117687, the ceramic materials 20a and 21a formed in a rectangular plate are embedded with heating resistors 20b and 21b, and both surfaces of the ceramic materials 20a and 21a are tube materials. 18 and 19 are in contact with the flat portions 18c and 19c, and lead wires 26 are connected to both ends of the heating resistors 20b and 21b. Reference numeral 27 denotes a thermoswitch attached to the metal blocks 18a and 19a.
[0020]
Here, the ceramic materials 20a and 21a constituting the ceramic heaters 20 and 21 are made of ceramics mainly composed of alumina, silicon nitride, aluminum nitride, and the like, and the heating resistors 20b and 21b are made of Ti (titanium). ), W (tungsten), Mo (molybdenum) or the like, or a carbide or nitride of these metals.
[0021]
The first and second ceramic heaters 20 and 21 are controlled by an energization control unit 30. The energization control unit 30 includes first and second relays 31 and 32 and a control unit 33 that controls these relays. Each of the relays 31 and 32 includes excitation coils 31a and 32a and the excitation coil 31a. , 32a and operating contacts 31b, 32b that are closed by energization. Each excitation coil 31a, 32a has one end connected to the power supply 34 and the other end connected to the control unit 33. The control unit 33 controls the energization / non-energization of each excitation coil 31a, 32a. I have to.
[0022]
The first relay 31 and the second relay 32 are provided in parallel to the power supply 34, and the movable contact 31b of the first relay 31 is connected in series with the first ceramic heater 20, When the movable contact 31b is closed by energization of the exciting coil 31a, energization to the first ceramic heater 20 is started. The movable contact 32b of the second relay 32 is connected in series with the second ceramic heater 21. When the movable contact 32b is closed by energization of the exciting coil 32a, the movable contact 32b is connected to the second ceramic heater 21. Energization is started.
[0023]
The control unit 33 is constituted by an electric circuit with a built-in microcomputer, for example, and inputs a signal from a water temperature sensor 35 for detecting the cooling water temperature, and performs arithmetic processing on this signal according to a predetermined program given in advance. As shown in FIG. 4, energization control is performed on the excitation coils 31 a and 32 a.
[0024]
The energization control process shown in FIG. 4 is started at the same time as the engine is started. When the coolant temperature is higher than the first predetermined temperature, the excitation coils 31a of the first and second relays 31 and 32 are used. , 32a are turned off, the first and second ceramic heaters 20, 21 are turned off, and only the waste heat of the engine 1 is used (steps 50, 52). On the other hand, when the cooling water temperature is equal to or lower than the first predetermined temperature and higher than the second predetermined temperature set lower than the first predetermined temperature, the first The exciting coil 31a of the relay 31 is energized, the exciting coil 32a of the second relay 32 is de-energized, and only the first ceramic heater 20 is turned on to generate heat, and the cooling water is supplementarily heated by the ceramic heater 20 (step 50). , 54, 56). Further, when the cooling water temperature that requires heating capacity is equal to or lower than the second temperature, both the first and second exciting coils 31a and 32a are energized, and the first and second ceramic heaters 20 and 21 generate heat. To promote the heating of the cooling water (steps 50, 54, 58).
[0025]
In the above configuration, the temperature of the cooling water is very low immediately after starting the engine in the low outside air, and the circulation of the cooling water to the radiator 12 is interrupted by the thermostat 14, and the heat dissipation of the cooling water is avoided. At the same time, the control unit 33 of the energization control unit 30 energizes the exciting coils 31a and 32a of the first and second relays 31 and 32, whereby the first and second ceramic heaters 20 and 21 generate heat. start.
[0026]
Thereby, the cooled cooling water in the water jacket 10 passes through the first pipe member 18 via the pipe member 22, and passes through the first pipe member 18 to pass through the first and second ceramic heaters 20, 21. Heat is transferred through the tubing 18 and warmed. After that, the U-shaped pipe 24 makes a U-turn to enter the second pipe material 19, and in the process of passing through this pipe material 19, the heat of the first and second ceramic heaters 20, 21 is transmitted through the pipe material 19, Be warmed up.
[0027]
The cooling water heated in this way flows into the heater core 8 through the remaining pipe material 23 in the upstream path, and radiates heat to the air passing through the air conditioning duct 6 to warm the air. Then, the cooling water that has passed through the heater core 8 passes through the pipe 16, reaches the water pump 11, and is returned to the water jacket 10.
[0028]
Since the engine 1 is gradually warmed as time passes after starting, the temperature of the cooling water gradually increases due to waste heat from the engine 1, but as described above, the first and second ceramic heaters 20. , 21 can be used to heat the cooling water in an auxiliary manner, so that the temperature of the cooling water can be quickly raised, and a rapid heating request immediately after the engine is started can be met. Even if a sufficient time has elapsed after the engine 1 is started, if the temperature of the cooling water is equal to or lower than the second predetermined temperature in order to improve the efficiency of the engine, the first and second ceramic heaters 20, Similarly, 21 generates heat and the cooling water temperature is increased, and the cooling water having a required temperature can be supplied to the heater core 8.
[0029]
If the cooling water temperature is between the first predetermined temperature and the second predetermined temperature, the control unit 33 deenergizes the second relay 32, energizes only the first relay 31, and performs auxiliary heating of the cooling water. Is continued only by the first ceramic heater 20. If the water temperature is higher than the first predetermined temperature, the first relay 31 is also de-energized, the cooling water is not heated by the ceramic heater, and the heating control using only the waste heat of the engine 1 is performed.
[0030]
As described above, the auxiliary heating of the cooling water is performed by transmitting the heat of the first and second ceramic heaters 20 and 21 to the first and second pipe members 18 and 19 sandwiching the heat and heating the pipe members. Therefore, the cooling water does not come into contact with the ceramic heaters 20 and 21, and a safe heating device can be provided. In addition, the first and second ceramic heaters 20 and 21 are sandwiched between the first and second tube materials and the surfaces thereof are protected by these tube materials. Even if an external force is applied, the ceramic heaters 20 and 21 are configured. There is little fear that it will break, and a durable heating device can be provided.
[0031]
In addition, the number of ceramic heaters 20 and 21 to be energized can be adjusted according to the cooling water temperature and the change thereof, and the electric power can be used efficiently. Also, since a plurality of ceramic heaters are used for one auxiliary heating device 17, even when the power capacity is large, the amount of current supplied to each ceramic heater can be reduced, and harnesses and couplers such as lead wires It becomes easy to design.
[0032]
In this configuration, the heating amount is adjusted by one auxiliary heating device 17, but the same heating control is performed by providing a plurality of auxiliary heating devices on the cooling water path and supplying the plurality of auxiliary heating devices to a power source. The number of auxiliary heating devices that are connected in parallel to each other and energized according to the cooling water temperature may be adjusted.
[0033]
In addition, even if it is in the structure of the electricity supply control part 30 which controls electricity supply to the 1st and 2nd ceramic heaters 20 and 21, not only the said structure but the structure using the water temperature switch closed below predetermined water temperature It is good. For example, what is shown in FIG. 5 is one in which the water temperature of each ceramic heater 20, 21 is made different, and each ceramic heater 20, 21 is controlled by a separate water temperature switch 36, 37. The excitation coil 31a of the first relay 31 connected to the power supply 34 is connected in series with the first water temperature switch 36, the excitation coil 32a of the second relay 32 is connected in series with the second water temperature switch 37, The temperature at which the first water temperature switch 36 is closed (first predetermined temperature) is set higher than the temperature at which the second water temperature switch 37 is closed (second predetermined temperature).
[0034]
Therefore, also in this case, when the cooling water temperature is higher than the first predetermined temperature, the excitation coils 31a and 32a of the first and second relays 31 and 32 are set in a non-energized state, and the first and second The ceramic heaters 20 and 21 are turned off, and the auxiliary heating of the cooling water is not performed, and only the waste heat of the engine 1 is used. When the cooling water temperature is equal to or lower than the first predetermined temperature and higher than the second predetermined temperature, the exciting coil 31a of the first relay 31 is energized and the exciting coil 32a of the second relay 32 is de-energized. Only the first ceramic heater 20 is caused to generate heat, and the cooling water is supplementarily heated only by the first ceramic heater 20. Further, when the cooling water temperature is equal to or lower than the second predetermined temperature, both the first and second exciting coils 31a and 32a are energized, and the first and second ceramic heaters 20 and 21 are heated to generate cooling water. Promote heating.
[0035]
In the above configuration, the cooling water path upstream of the heater core 8 is formed in a U-bent shape, and the first and second pipe members 18 and 19 are provided in the vicinity of the upstream path, and these The cooling water was made to flow sequentially through the pipe material. In this configuration, since the cooling water sequentially flows through both pipe materials, the temperature rise of the cooling water increases, but there is a concern that the passage resistance may be somewhat increased by passing through the U-shaped tube 24.
[0036]
In view of this point, as shown in FIG. 6 (a), a part of the upstream path is bifurcated into branch paths 15a and 15b extending in parallel. Even when the second pipe members 18 and 19 are provided, the first pipe member 18 is provided on the upstream path of the heater core 8 and the second pipe member 19 is provided on the heater core 8 as shown in FIG. You may make it provide on a downstream path | route.
[0037]
According to the configuration shown in FIG. 6A, the cooling water in the water jacket 10 flows separately from the branch paths 15a and 15b in the process of passing through the upstream path, and is provided in each of the branch paths 15a and 15b. Heated when passing through the first and second pipe members 18, 19, gathered downstream of the auxiliary heating device 17, and flows into the heater core 8. Therefore, according to such a configuration, since the cooling water in the path is branched and any one of the pipes 18 and 19 is passed only once, the temperature rise of the passing cooling water is not large, Since there is no abrupt bend, the passage resistance can be reduced. Further, similarly to the above configuration, the auxiliary heating device 17 can be installed only by handling the upstream path.
[0038]
Further, according to the configuration shown in FIG. 6B, the cooling water in the water jacket 10 is warmed through the first pipe member 18 in the process of passing through the upstream path, and then flows into the heater core 8. Then, after being dissipated by the heater core 8, it is warmed through the second pipe material 19 in the process of passing through the downstream path, and returned to the water jacket 10. When viewed as a circulation system between the water jacket 10 and the heater core 8, the cooling water is sequentially heated by the first and second pipe members 18, 19, so that cooling can be performed as quickly as in the first configuration example. Since the temperature of the water is expected to increase, and the flow direction of the cooling water in each path is not changed by the auxiliary heating device 17, there is an advantage that an increase in passage resistance can be suppressed.
[0039]
FIG. 7 shows another aspect of the auxiliary heating device 17. Hereinafter, differences from the aspect shown in FIG. 1 will be mainly described, and the same portions will be denoted by the same reference numerals and description thereof will be omitted.
[0040]
A feature of this configuration is that a bypass path 41 passing through the heat storage unit 40 is provided in the path 15 upstream of the heater core 8, and an auxiliary circulation path 42 for heating and circulating the surrounding cooling water is provided in the heat storage unit 40. There is.
[0041]
That is, the auxiliary heating device 17 is provided with a first opening / closing valve 43 configured by an electromagnetic valve or the like in the upstream path 15 connecting the water jacket 10 and the heater core 8, and the bypass path 41 is connected to the first opening / closing valve 43. The second on-off valve 44 is provided on the upstream side of the heat storage unit 40 in the bypass path 41, and the bypass path 41 is provided on the downstream side of the heat storage unit 40 in the bypass path 41. The check valve 45 which permits only the outflow from is provided.
[0042]
In addition, the auxiliary circulation path 42 is provided with a circulation pump 46, and as shown in FIG. 1, a middle passage is formed in a U-bent shape to form a path that is close in parallel, and the first and second paths are formed on the path. Second pipe members 18 and 19 are provided, and the first and second ceramic heaters 20 and 21 are sandwiched between these pipe members. The pipes 18 and 19 and the ceramic heaters 20 and 21 have the same structure as that shown in FIGS. 2 and 3, and both pipes are connected by a U-shaped pipe 47 to constitute a part of the auxiliary circulation path 42. ing. Since other configurations are the same as those described above, description thereof is omitted.
[0043]
Therefore, according to such a configuration, the first on-off valve 43 is opened and the second on-off valve 44 is closed during preheating before starting the engine, and the circulation pump 46 and the ceramic heaters 20 and 21 are energized. Thereby, the cooling water around the heat storage unit 40 is circulated through the auxiliary circulation path 42 and heated, and heat is stored in the heat storage unit 40.
[0044]
When the first on-off valve is closed 43 and the second on-off valve 44 is opened when the engine is started, the cooling water sent from the water jacket 10 passes through the bypass path 41 in the middle of the upstream path and the heat storage unit. 40, the heat stored in the heat storage unit 40 in the process is absorbed, mixed with the warmed cooling water around the heat storage unit 40, and the heater core through the check valve 45 as a high temperature cooling water 8 is sent.
[0045]
Therefore, the cooling water circulating between the water jacket 10 and the heater core 8 is warmed at once, and warm air can be supplied to the passenger compartment from the beginning of the engine start. Moreover, even if the engine 1 is stopped, the cooling water can be kept at a high temperature for a long time by the heat stored in the heat storage unit 40, and the decrease in the cooling water temperature when the vehicle is stopped can be mitigated.
[0046]
Even in such a configuration, contact between the first and second ceramic heaters 20 and 21 and the cooling water can be avoided, damage to the ceramic heaters 20 and 21 can be suppressed, and ceramic. Needless to say, the first and second circuits provided on the auxiliary circulation path 42 have the same effects as the above-described configuration, such as the ability to change the number of energizations of the heater and supply the necessary amount of heat as required. The energization control of the ceramic heaters 20 and 21 may be performed as shown in FIG. 3 or FIG. 5 even if the two pipe members 18 and 19 are provided on each branch as shown in FIG. Control may be performed by the unit 30.
[0047]
Moreover, in the above embodiment, in order to improve the thermal efficiency of the auxiliary heating apparatus 17, you may add a heat insulating material to the circumference | surroundings and the junction part with the piping 15. FIG.
[0048]
【The invention's effect】
As described above, according to the invention according to claim 1 , the auxiliary heating device includes the heat storage unit that allows passage of the cooling water, and the auxiliary that circulates the cooling water separately from the path, including the heat storage unit. A circulation path, a circulation pump interposed in the middle of this auxiliary circulation path, at least two pipe materials that are interposed in the middle of the auxiliary circulation path and circulate cooling water, and an electric heater sandwiched between these pipe materials Therefore, by using the electric heater and the heat storage unit in combination, the heat storage to the heat storage unit is performed with the electric heater, and at the initial start of the internal combustion engine, the cooling water sent to the hot water heat exchanger is immediately generated by the heat stored in the heat storage unit. The cooling water temperature can be reduced when the internal combustion engine is stopped.
[0049]
According to the second aspect of the present invention, if a plurality of electric heaters sandwiched between the pipes are provided and the number of electric heaters to be energized is switched according to the cooling water temperature, the requirement for immediate warming and the heating load can be met. Accordingly, a necessary number of electric heaters can be used, and the electric power can be used efficiently. Also, considering the case where the amount of current is increased as the heating load increases, in one electric heater, it is necessary to make the harness and coupler compatible with a high current, but if a plurality of electric heaters are used, Even when the same amount of heat is obtained, the supply current amount of each electric heater can be reduced, and the design of a harness, a coupler, and the like is facilitated.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a vehicle heating apparatus according to the present invention.
FIG. 2 is an exploded perspective view showing first and second tube members constituting an auxiliary heating device used in the vehicle heating device and a ceramic heater sandwiched between the tube members.
FIG. 3 is a diagram showing an auxiliary heating device and an energization control unit of a ceramic heater used for the auxiliary heating device.
4 is a flowchart illustrating an example of a control operation of the control unit of FIG. 3;
FIG. 5 is a diagram illustrating another example of the energization control unit of the ceramic heater used in the auxiliary heating device.
FIG. 6 is a view showing another attachment mode of the first and second pipe members.
FIG. 7 is a diagram illustrating another configuration example of the auxiliary heating device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Engine 8 Heater core 15 Upstream path | route 15a, 15b Branch path 17 Auxiliary heating apparatus 18 1st pipe material 19 2nd pipe material 20 1st ceramic heater 21 2nd ceramic heater 40 Heat storage unit 46 Circulation pump 42 Auxiliary circulation path

Claims (5)

  In a vehicle heating apparatus provided with a hot water heat exchanger that uses cooling water of an internal combustion engine as a heat source, an auxiliary heating device is provided in the course of circulating the cooling water to the hot water heat exchanger. A heat storage unit that allows passage of the cooling water; an auxiliary circulation path that includes the heat storage unit and circulates the cooling water separately from the path; and a circulation pump that is interposed in the middle of the auxiliary circulation path; A vehicle heating apparatus comprising: at least two pipe members that are interposed in the middle of an auxiliary circulation path and through which the cooling water flows, and an electric heater sandwiched between the pipe members. Electric heater sandwiched by the tube material provided with a plurality of, the vehicle heating apparatus according to claim 1, wherein switching the number of the electric heater to be energized in response to the coolant temperature. The auxiliary circulation path is formed in a U-bent shape, thereby creating a portion where the upstream paths are close to each other and facing each other, and the two pipe members are interposed in the middle of each of the opposed upstream paths. The vehicle heating device according to claim 1. A branch path is formed in the auxiliary circulation path to branch the cooling water and flow in parallel, and to merge again on the downstream side , so that the two pipe members are interposed in the middle of each of the parallel branch paths. The heating device for vehicles according to claim 1 characterized by things.   The vehicle heating device according to claim 1, wherein the electric heater is a ceramic heater.

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