JP2001097028A - Heater for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop the energization to electric heaters by raising the temperature in a cabin even when the temperature of a cooling water of an engine is low, and prevent the excessive load on a battery. SOLUTION: The cooling water is allowed to flow in a core part 2 of a heat exchanger 1a for heating disposed in a duct 22, and electric heaters 5a and 5a are built therein. The detection signal of a temperature sensor 30 to detect the temperature of the air on the downwind side of the core part 2 is inputted in a controller 31 to control the energization to the electric beaters 5a and 5a. The controller 31 reduces or stops the energization to the electric heaters 5a and 5a when the temperature of the air is high.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an automobile heating apparatus for heating an interior of an automobile. In particular, the present invention, as a heat exchanger for heating for heating the air, mainly heats this air with engine cooling water,
When the temperature of the cooling water is low, an automotive heater using a structure in which the air is heated by an electric heater is used to realize a structure without imposing an excessive load on the battery.

[0002]

2. Description of the Related Art Conventionally, heater cores for heating air with cooling water of a vehicle driving engine have been widely used for heating the interior of an automobile. However, the temperature of the cooling water is not necessarily increased in consideration of heating in a cold region due to the improvement in engine combustion efficiency in recent years or the reduction in the amount of waste heat of the engine accompanying the realization of a hybrid vehicle. In some cases, it does not rise sufficiently. In view of such circumstances, a heating heat exchanger combining a heater core and an electric heater has been conventionally considered.

FIG. 21 shows an example of a heating heat exchanger 1 described in Japanese Patent Application Laid-Open No. H11-151926, which is considered in view of such circumstances. This heating heat exchanger 1 is composed of a pair of headers (FIG. 2) spaced from each other.
1 has a core portion 2 provided between them.
The core portion 2 includes a plurality of heat transfer tubes 3 and 3a each having an opening at both ends of the headers, and corrugated fins 4 and 4 sandwiched between adjacent heat transfer tubes 3 and 3a. Consists of The openings at both ends of each of the heat transfer tubes 3 are communicated with each of the headers. Further, a plate-shaped electric heater 5 is arranged between any of the heat transfer tubes 3a, 3a constituting the core portion 2, and between both surfaces of the electric heater 5 and the adjacent heat transfer tubes 3a, 3a. Also hold the fins 4,4.

When the heat exchanger 1 for heating as described above is used, the temperature of the core section 2 is raised by flowing cooling water for the traveling engine through the heat transfer tubes 3 and 3a. The air flowing through the section 2 in the direction of the arrow α is heated to be used for heating the interior of the automobile. If the temperature of the cooling water has not risen sufficiently to perform heating, the electric heater 5 is energized, and the temperature of the electric heater 5 and the adjacent fins 4, 4 is increased. Helps increase the temperature of the air flowing in the direction of arrow α. In the case of the structure shown in FIG. 21, the heat transfer tube 3 adjacent to the electric heater 5
a, 3a, one half of the end opening of each of these heat transfer tubes 3a,
The heat transfer tubes 3a, 3a are closed by lid members 6, 6, which are provided integrally with the heat transfer tubes 3a, and the flow rate of the cooling water flowing through the heat transfer tubes 3a, 3a is reduced. With such a configuration, when energizing the electric heater 5, the amount of heat energy generated by the electric heater 5 is taken away by the cooling water flowing through the heat transfer tubes 3a, 3a.

[0005] Further, as a heating apparatus for an automobile incorporating a heating heat exchanger provided with the above-described electric heater, one described in JP-A-11-42936 has been conventionally known. The automotive heating device described in this publication includes a duct for circulating air for heating the interior of the automobile, and a blower for blowing air into the duct. A heating heat exchanger with a heater is arranged. In the case of the vehicle heating device described in the above publication, the electric heater is energized in accordance with the temperature of the cooling water of the vehicle engine flowing through the heat transfer tube constituting the heating heat exchanger. I control it.

[0006]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No.
In the case of the heating device for a vehicle described in Japanese Patent No. 42936, when the vehicle is mounted in a vehicle equipped with an engine having a small amount of waste heat and is used in a cold region, the state in which the power supply to the electric heater is not stopped may occur. That is, the temperature of the cooling water of the engine having a small amount of waste heat does not increase so much even after a considerable time has elapsed since the start. For this reason, even when the temperature in the vehicle interior is sufficiently increased, the energization of the electric heater is continued, and the load on the battery becomes excessive.
The automotive heating device of the present invention has been invented in view of such circumstances.

[0007]

The heating device for a vehicle according to the present invention has a duct for flowing air for heating the interior of the vehicle, similarly to the above-described heating device for a vehicle. An air blower for blowing air into the duct, and a heating heat exchanger provided in the duct for heating the air. The heating heat exchanger includes a pair of headers spaced apart from each other, and a plurality of heat transfer tubes each having an opening at both ends thereof passing through each of the headers. It is provided with a core portion provided therebetween and an electric heater arranged between any of the heat transfer tubes constituting the core portion.

[0008] In particular, in the automotive heating apparatus according to the present invention, a temperature sensor is provided in the duct on the leeward side of the core, and detects the temperature of air passing through the core. A controller that controls energization of the electric heater based on a detection signal of the sensor. And
When the temperature of the air passing through the core portion is high, the controller reduces the amount of electricity to the electric heater or stops the electricity to the electric heater.

[0009]

According to the heating apparatus for an automobile of the present invention constructed as described above, when the temperature of the air passing through the core rises to such an extent that the temperature in the interior of the automobile can be sufficiently increased, the air flows through each heat transfer tube. Power supply to the electric heater is stopped regardless of the temperature of the cooling water. Therefore, even when the battery is installed in an automobile equipped with an engine having a small amount of waste heat and is used in a cold region, it is possible to prevent an excessive load on the battery.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS.
2 shows a first example of an embodiment of the present invention corresponding to FIG. The members constituting the heating heat exchanger 1a to be incorporated in the vehicle heating device of this embodiment are made of an aluminum alloy, except for the portion related to the electric heater. And
These aluminum alloy parts are brazed to each other. As the brazing material for brazing, a material laminated on the surface of at least one of the members that abut each other is used.

First, a heating heat exchanger 1a to be incorporated in a vehicle heating apparatus according to the present invention and an electric heater 5a constituting the heating heat exchanger 1a will be described with reference to FIGS. As shown in FIG. 1, the heating heat exchanger 1a has a core portion 2 provided between a pair of headers 7a and 7b spaced from each other. This core part 2
A plurality of heat transfer tubes 3, 3, each having an opening at each end leading to each of the headers 7 a, 7 b, and adjacent heat transfer tubes 3,
And corrugated fins 4, 4 sandwiched between the three. Then, open both ends of these heat transfer tubes 3, 3
Each of the headers 7a and 7b communicates with each other. Further, a plurality of (three in the example shown) electric heaters 5a, 5a each having a plate shape are arranged between any of the heat transfer tubes 3, 3 constituting the core portion 2. The fins 4, 4 are also sandwiched between both surfaces of the electric heaters 5a, 5a and the adjacent heat transfer tubes 3, 3, respectively. Although the heat transfer tubes 3 and 3 and the fins 4 and 4 are brazed to each other, the electric heaters 5a and 5a and the fins 4 and 4 are connected to each other by heat transfer such as heat transfer silicon as shown in FIG. Bonding is performed with adhesives 15 having good heat properties.

In the illustrated example, one of the headers 7a (upper part in FIG. 1) is divided into an inlet chamber and an outlet chamber at the center, and an inlet pipe 8 is provided in the inlet chamber, and an outlet pipe is provided in the outlet chamber. Outlet pipes 9 are provided respectively. When the heating heat exchanger 1a is used, cooling water (hot water) whose temperature has risen in the water jacket of the traveling engine is sent from the inlet pipe 8 to the inlet chamber of the header 7a. The cooling water flows through the heat transfer tubes 3, 3 constituting one half of the core part 2 toward the other (lower in FIG. 1) header 7 b, and is then turned back inside the other header 7 b, The inside of the heat transfer tubes 3, 3 constituting the other half of the core portion 2 is sent toward the outlet chamber of the header 7 a and returned from the outlet tube 9 into the water jacket. Therefore, if air for heating is made to flow through the core portion 2, the air can be heated.

Although illustration and detailed description are omitted,
In the case of the heating heat exchanger 1a of the present example, the flow passage area of the end opening of the heat transfer tubes 3, 3 adjacent to the electric heaters 5a, 5a is set to the sheet plate forming the headers 7a, 7b. It is squeezed by the squeezing holes formed at 10, 10. That is, each of the headers 7a and 7b is formed by combining the sheet plates 10 and 10 with the header main bodies 11a and 11b in the middle, respectively, and both ends of the heat transfer tubes 3 and 3 are open at both ends. The through holes formed in the sheet plates 10, 10 lead to the internal spaces of the headers 7a, 7b. In the case of this example, each of the above-described electric heaters 5a,
By making the through holes facing the end openings of the heat transfer tubes 3 and 3 adjacent to 5a the above-described throttle holes, these heat transfer tubes 3 and 3
The flow path area of the end opening 3 is narrowed.

In this way, by reducing the flow passage area of the end openings of the heat transfer tubes 3, 3 adjacent to the electric heaters 5a, 5a, the air supply based on the energization to the electric heaters 5, 5 is performed. The temperature can be efficiently controlled. That is, each of the sheet plates 1 constituting each of the headers 12a and 12b
The flow rate of the cooling water flowing through the heat transfer tubes 3, 3 adjacent to the electric heaters 5a, 5a is reduced by the respective throttle holes formed in a part of the electric heaters 5, 0, and
The amount of heat taken by the cooling water flowing through each of the heat transfer tubes 3, 3 is kept small.

In the case of this embodiment, each of the above-mentioned electric heaters 5a,
5a, as shown in FIGS. 3 to 7, thin films of resistors 13, 13 are attached to the front and back surfaces of a flat insulating plate 12, and these resistors 13, 13 are covered with insulating layers 14, 14, respectively. Become. As the insulating plate 12, an enamel plate or the like in which a glassy film of about 10 μm is formed on the surface of a steel plate as a base material is used. Such an insulating plate 12 can be made sufficiently thin (for example, to a thickness of about 0.5 to 1.0 mm) as long as the rigidity of the obtained electric heaters 5a and 5a can be secured. The resistors 13 are integrally baked on the surface of the insulating plate 12, for example.
AgPd or the like having a thickness of about 10 μm can be used. Further, as the insulating layers 14 and 14, a layer having a thickness of about 10 μm, such as a glass material, which is integrally baked on both the front and back surfaces of the insulating plate 12 so as to cover the resistors 13 and 13 can be used.

As described above, the electric heaters 5a, 5a used in the present embodiment are formed of resistors 13, 13 such as AgPd as heating elements.
Is used, the thickness is set to the value described in JP-A-11-151.
It can be made much thinner than an electric heater incorporated in a conventionally known heating heat exchanger described in, for example, Japanese Patent No. 926. That is, in the case of an electric heater incorporated in a conventionally known heating heat exchanger, since a positive temperature coefficient thermistor whose resistance value increases as the temperature rises is used, a pair of positive and negative electrodes is used. Thickness increases, such as the need for a board. Also, due to the characteristics of the positive temperature coefficient thermistor, the amount of heat generated by the obtained electric heater decreases as the temperature rises. It is not suitable for a structure for controlling the current supply. On the other hand, the electric heaters 5a and 5a used in the present example having the above-described configuration can be formed thin, have a substantially constant resistance value irrespective of temperature rise, and generate heat in accordance with the amount of electricity. Since it can be controlled, it is suitable for a structure in which energization to the electric heater is controlled by the temperature of the air passing through the core.

In the actual case, each of the resistors 13, 13
Is attached to the surface of the insulating plate 12 in a belt-like and meandering state as shown in FIG. Then, each of the resistors 13
Is connected directly to one end of the first terminal 16, 16 and the other end is connected to the base of the second terminal 17, 17 via a fuse 18. Accordingly, each of the electric heaters 5a, 5a is represented by a circuit diagram as shown in FIG. The bases of the first and second terminals 16 and 17 and the fuse 18 are also covered by the insulating layers 14 and 14. That is, in the completed state of each of the electric heaters 5a, 5a, only the first half of the first and second terminals 16, 17 is exposed from the insulating layers 14, 14.

The distal ends of the first and second terminals 16 and 17 exposed from the insulating layers 14 and 14 are
As shown in FIG. 6, each of the above-described electric heaters 5a, 5a
Is connected to an end of a harness 19 for supplying power to the harness.
Further, the entirety of the first and second terminals 16 and 17 and the end of the harness 19 are covered with a protective tube 20 made of an insulating material from the end of each resistor 13. As the protective tube 20, a heat-shrinkable synthetic resin tube or the like can be preferably used. If necessary, the protective tube 20 may be filled with an insulating material 21 such as rubber or grease.

The above-described electric heaters 5a, 5a
a and the harness 19 attached to each of the electric heaters 5a, 5a are, as described above, a portion through which electricity passes, that is, each of the resistors 13, 13, the first and second terminals 16, 17,
The conductors exposed from the insulating coating at the ends of the fuse 18 and the harness 19 are all covered with an insulating material. Therefore, even if water droplets (such as raindrops mixed in the outside air taken in from outside the vehicle compartment during rainy weather) adhere to the surfaces of the electric heaters 5a, 5a and the harness 19 attached to the electric heaters 5a, 5a. There will be no leakage. Therefore, it is not necessary to consider the installation positions and installation directions of the electric heaters 5a and 5a and the harness 19 attached to the electric heaters 5a and 5a.

Next, with respect to the configuration of the heating apparatus for an automobile of the present invention, including the heating heat exchanger 1a in which the above-described electric heaters 5a, 5a are incorporated in the core portion 2,
This will be described with reference to FIG. A blower 23 for blowing air into the duct 22 is provided at an upstream end of a duct 22 for circulating air for heating the interior of the automobile. An evaporator 24 and the heating heat exchanger 1a are provided in the middle of the duct 22 in order from the upstream side. A bypass passage 25 is provided on the side of the heating heat exchanger 1a, and an air mixing door 26 is provided on the upstream side of the heating heat exchanger 1a and the bypass passage 25. This air mix door 26 is for adjusting the temperature of the air blown into the vehicle interior by adjusting the ratio of the air passing through the heating heat exchanger 1a and the air passing through the bypass flow passage 25. It is.

Further, a defrost outlet (DEF) 27 for blowing air for air conditioning to the inner surface of the windshield is provided at a downstream end of the duct 22, and a ventilation for blowing the air toward the upper body of the occupant. An outlet (VENT) 28 and a foot outlet (FOOT) 29 for blowing out the foot similarly are provided. Each of the outlets 27 to 29 is provided with a door for opening and closing the outlet 27 to 29. When air conditioning in a car interior, each of these outlets 2
Open at least one outlet of 7 to 29,
Blows air into the cabin.

In particular, in the case of the automotive air conditioner of the present invention, the core 2 passes through the duct 22 to the leeward side of the core 2 (FIG. 1) of the heating heat exchanger 1a. A temperature sensor 30 for detecting the temperature of the air is provided, and a detection signal of the temperature sensor 30 is input to a controller 31. The controller 31 controls the energization of the electric heaters 5a, 5a incorporated in the core 2 of the heating heat exchanger 1a. In the case of the illustrated example, the controller 3
First, a detection signal of an outside air temperature sensor 32 for detecting the outside air temperature outside the vehicle compartment, a detection signal of an inside air temperature sensor 33 for detecting the inside air temperature inside the vehicle compartment, and a remaining amount of the battery 34 are detected (actually, a voltage is detected. The detection signal of the battery sensor 35, the detection signal of the engine rotation sensor 37 for detecting the operating state of the engine 36, and the detection signal of the water temperature sensor 38 for detecting the temperature of the cooling water of the engine 36 You are typing. Further, in the case of this example, although not shown, a signal indicating the open / closed state of each of the outlets 27 to 29 is also input to the controller 31. A signal indicating the open / closed state of each of the outlets 27 to 29 is, for example,
It can be taken out of the controller of the air conditioner for automobiles.
An air-conditioning switch 39 for controlling the start / stop of the air conditioner for the vehicle is provided between the battery 34 and the controller 31 between the water jacket of the engine 36 and the heat exchanger 1a for heating. Are provided with cooling water pipes 40 for flowing cooling water through the heat transfer tubes 3 and 3 (FIG. 1) of the heating heat exchanger 1a.

The controller 31 constituting the air conditioner for a vehicle of the present invention having the above-described configuration is adapted to control the temperature of the air passing through the core 2 based on the detection signal of the temperature sensor 30 when the temperature is high. The electric heaters 5a, 5a
The power supply to the electric heaters 5a and 5a is stopped. Also, the controller 31
Is based on the detection signal of the outside air temperature sensor 32 and only when the outside air temperature is equal to or lower than a predetermined value,
a, 5a can be energized. Also, the controller 31
Enables power to the electric heaters 5a and 5a only when the remaining amount of the battery 34 is equal to or more than a predetermined value (for example, 9 V) based on the detection signal of the battery sensor 35. In addition, the controller 31 controls each of the outlets 2.
Based on the signals indicating the open / close states of 7 to 29, the electric heaters 5a and 5a can be energized only in a blowout state in which there is a possibility of blowing out warm air. Furthermore,
Based on the detection signal of the water temperature sensor 38, the controller 31 enables power to the electric heaters 5a and 5a only when the temperature of the cooling water is equal to or lower than a predetermined value. The control of energization of the electric heaters 5a and 5a is performed by relay switches 42a and 42 provided between the electric heaters 5a and 5a and the battery 34 and the alternator 41.
This is performed by connecting and disconnecting b and 42c.

Next, the operation of the heat exchanger for an automobile of the present invention configured as described above will be described with reference to FIGS. First, when the air-conditioning switch 39 is closed (turned on) as shown in FIG.
The environmental conditions are read based on the detection signals sent from 2, 33, 35, 37, and 38. Then, in the next steps 2 to 6, it is determined whether or not the electric heaters 5a, 5a are energized. The order of steps 2 to 6 is not particularly limited, but the following description will be made in the order shown in FIG.

First, in step 2, if the outside air temperature is lower than a predetermined value (for example, 10 ° C.), the electric heater 5
a, 5a can be energized, and if it is equal to or greater than the predetermined value, these electric heaters 5a, 5a
The energization to a is stopped. Next, in step 3, the electric heaters 5a and 5a can be energized only when the engine 36 is rotating. Each electric heater 5
a, the power supply to 5a is stopped. This is alternator 41
This is to prevent an excessive load from being applied to the battery 34 when the operation is stopped. Next, in step 4, the battery 3
Each of the electric heaters 5 only when the remaining amount of the electric heater 4 is equal to or more than a predetermined value.
a, 5a can be energized, and when the remaining amount is less than a predetermined value, the electric heater 5
a, 5a is stopped to prevent the battery 34 from being excessively consumed. Next, in step 5, each of the electric heaters 5 is opened only when the open / close state of each of the outlets 27 to 29 is likely to perform warm air blowing.
a, 5a is energized, and there is no possibility that the open / closed state performs a warm air blowout, that is, a case where the air outlet into the vehicle compartment is a ventilation outlet, or in the middle of the cooling water pipe 40. When the provided hot water valve is closed, the power supply to the electric heaters 5a and 5a is stopped regardless of other conditions.

The open / close state in which warm air may be blown is defined as a DEF mode in which the defrost blowout port 27 is open, a FOOT mode in which the foot blowout port 29 is open, or a foot blowout mode. This is the case of the BI / LEVEL mode in which the mouth 29 and the ventilation outlet 28 are open. In the case of the VENT mode in which only the ventilation outlet 28 is open, there is no possibility that the warm air is blown out. Therefore, regardless of other conditions, the above-described electric heaters 5a, 5a
Stop supplying power to Further, in step 6, the temperature of the cooling water in the water jacket is set to a predetermined value (for example, 70
C)), the energization of each of the electric heaters 5a, 5a is enabled only when the temperature of the cooling water is equal to or higher than a predetermined value, regardless of other conditions.
The energization to a is stopped. Also, as is apparent from the above description, instead of corresponding to the open / closed state of each of the outlets 27 to 29, or while corresponding to this open / closed state,
When the hot water valve provided in the middle of the cooling water pipe 40 is closed, the above-mentioned electric heater 5
a, control for stopping the energization to 5a can also be performed.

In steps 2 to 6, the outside air temperature is lower than the predetermined value, the engine 36 is in operation, the remaining amount of the battery is higher than the predetermined value, and each of the outlets 27 to 2
9 is a state in which there is a possibility that hot air is blown out, and if it is determined that the temperature of the cooling water is lower than a predetermined value, in step 7, the electric heaters 5a, 5a
Turn on electricity.

In step 7, each of the electric heaters 5a,
5a, when the temperature of the core portion 2 of the heating heat exchanger 1a rises, in the next step 8, the blower 2
3 for controlling the startup and operation speed of the fan. This fan start control is performed as shown in FIG. 11 based on a signal from the temperature sensor 30 provided immediately downstream of the core section 2. That is, the temperature sensor 3
The blower 23 is started in a state in which the temperature of the air immediately after the leeward side of the core portion 2 detected by 0 exceeds a predetermined value (for example, 50 ° C.). In other words, when the temperature of the air immediately downstream of the leeward side is low, the blower 23 is kept stopped to prevent the cool air from blowing into the vehicle interior. After the blower 23 is started, the operating speed of the blower 23 is adjusted so that the temperature of the blown air passing through the core portion 2 detected by the temperature sensor 30 does not fluctuate significantly as compared with the predetermined value. For this purpose, the voltage applied to the motor of the blower 23 is controlled.

After the blower 23 has been started in this way, in the next step 9, it is necessary to bring the interior of the car to a desired temperature (a target temperature set by a control panel provided on the dashboard). Then, the target value of the blown air is calculated. Then, in the next step 10, each of the electric heaters 5a, 5a
Turn on electricity. That is, the controller 31 determines the relay switches 42a, 42a based on the difference between the blown air temperature detected by the temperature sensor 30 at that time and the target value.
b and 42c are connected and disconnected. That is, as shown in FIG. 12, when this difference is large, all the relay switches 42a, 4a,
2b and 42c are connected, and as the difference becomes smaller, the number of connected relay switches 42a, 42b and 42c is reduced.

In this manner, the electric heaters 5a, 5a
In step 11, while controlling the temperature of the blown air by energizing all or a part of the blower, the operation of the blower 23 is controlled so that the temperature of the blown air that has passed through the core portion 2 does not greatly fluctuate compared with the predetermined value. In order to adjust the speed, the voltage applied to the motor of the blower 23 is controlled as shown in FIG. In the case of this example, since such an operation speed control of the blower 23 is performed not by the cooling water temperature but by the blown air temperature, it is possible to perform an appropriate control according to a passenger's feeling.

Then, in the next step 12, it is determined whether or not the temperature of the blown air has reached the target value. If the temperature has reached the target value, the power supply to all the electric heaters 5a, 5a is stopped. , The respective relay switches 42a, 42b, 42c
All open. Thereafter, similarly to a general automotive air conditioner having a well-known structure, the temperature of the blown air is adjusted by the air mix door 26 as shown in the right end of FIG. Until the temperature of the blown air reaches the target value, the air mix door 26 keeps the bypass passage 25 completely closed. If the target value has not been reached, the procedure returns to step 1 again, and the above-described operation is repeated until the target value is reached.

As described above, the heating device for a vehicle according to the present invention stops energizing the electric heaters 5a and 5a when the blown air temperature reaches the target value. on the other hand,
Even when the amount of heat generated by the engine 36 is small and the temperature is cold, the time required to reach the target value can be shortened by operating in the inside air circulation state. That is, the duct 2
By opening the upstream end of the engine 2 only to the interior of the automobile and circulating the air taken in from the interior of the automobile to heat the interior of the automobile, even if the temperature of the cooling water of the engine 36 is not sufficiently high. Thus, the temperature of the blown air can be raised to the target value in a relatively short time. Therefore,
Even when the amount of heat generated by the engine 36 is small and the temperature of the cooling water does not rise sufficiently, energization of the electric heaters 5a and 5a can be stopped, so that an excessive load is not applied to the battery 34. Of course, after the temperature in the vehicle interior has risen sufficiently, the target value of the blown air temperature falls, so that outside air may be taken into the duct 22 while the power supply to the electric heaters 5a, 5a is stopped. Will be possible.

In the case of this embodiment, each of the electric heaters 5
Since the resistors 13 and 13 are used as the heating elements a and 5a, heat can be applied from the electric heaters 5a and 5a to the cooling water side to promote the temperature rise of the cooling water. When a positive temperature coefficient thermistor is used as the heating element as in the above-described conventional structure, the temperature of the heating element cannot be increased more than necessary for heating the air. Can be increased regardless of the temperature of the heated air. Therefore, the temperature of the blown air is increased while the inside air is circulating, and after the temperature of the blown air reaches the target value, when the temperature of the cooling water is equal to or lower than a predetermined value (for example, 40 ° C.), The energization to 5a is continued. That is, more electric power than necessary for heating the blown air is supplied, and the cooling water flowing in the heat transfer tubes 3, 3 adjacent to the electric heaters 5a, 5a is heated to form the cooling water. It can also increase the temperature. Each of the electric heaters 5a and 5a used in this example is provided with a fuse 1 as described above.
8, each of these electric heaters 5a, 5a
a rises excessively and the duct 22 made of synthetic resin
Such damage can be reliably prevented.

Next, FIGS. 13 to 15 show a second example of the embodiment of the present invention. In each of the electric heaters 5b and 5b used in this example, the resistors 13a and 13a are divided into a plurality of stages (three stages in the illustrated example) as shown in the circuit diagram of FIG. Then, the relay switches 42a, 42b, 42c
In accordance with the connection or disconnection, the whole or a part of each of the resistors 13a, 13a generates heat. Therefore, a plurality of (three in the illustrated example) electric heaters 5b and 5b incorporated in the heating heat exchanger 1b generate heat evenly. On the other hand, in the case of the first example described above, there is a state in which, when any one of the electric heaters 5a generates heat, the other electric heater 5a does not generate heat at all.

In the case of this example based on such a difference,
The effect that the air passing through the core portion 2 of the heating heat exchanger 1b is uniformly heated to reduce the temperature unevenness of the blown air, which is not achieved by the structure of the first example. Can do things. Since the structure and operation of the other parts are the same as those of the first example described above, the same parts are denoted by the same reference numerals, and duplicate description will be omitted.

FIGS. 16 and 17 show third and fourth examples of the embodiment of the present invention. In the case of the electric heater 5a used in the first example described above, the first and second terminals 16 and 17 for connecting the ends of the harness are provided at both ends of one end. On the other hand, in the case of the electric heater 5c of the third example shown in FIG.
Is provided at one end of one edge. Further, in the case of the electric heater 5d of the fourth example shown in FIG. 17, the first and second terminals 16, 17 are provided at both ends of one end.

FIG. 18 shows a fifth embodiment of the present invention. In the case of this example, arcuate locking recesses 43 are formed at both ends in the longitudinal direction of the electric heater 5e, and the sheet plates that constitute the mutually facing inner side surfaces of the pair of headers 7a (7b). 10, a leaf spring 44, which is an elastic member, is mounted. Then, by engaging the leaf spring 44 with the locking recess 43, the adhesive 1
Even before the hardening 5 (FIG. 2) hardens, the electric heater 5e is prevented from falling out of the core portion 2. By employing such a structure, a jig for holding down the electric heater 5e is not required even if the adhesive 15 having a long curing time is used. In addition, since the leaf spring 44 can be left assembled to the heating heat exchanger together with the electric heater 5e, the heating heat exchanger can be shipped while the adhesive 15 is not cured. .

FIG. 19 shows a sixth embodiment of the present invention corresponding to claim 7. In the case of this example, the heating heat exchanger 1c is a condenser constituting a heat pump cycle, and the fluid flowing through each of the heat transfer tubes 3, 3 is refrigerant vapor. Such a heating heat exchanger 1c may be used, for example, for indoor heating of an electric vehicle.
The automotive heating device of the present invention can also be implemented with a structure incorporating such a heating heat exchanger 1c. In this case, even if the compressor incorporated in the heat pump cycle is small, a sufficient heating effect can be obtained at low temperatures. Conventionally, the auxiliary heater 46 is assembled to the condenser 45 constituting the heat pump cycle by a structure as shown in FIG. 20, but the structure shown in FIG. Compact and lightweight.

[0039]

Since the present invention is constructed and operates as described above, a sufficient heating effect can be obtained even when the temperature of the heating fluid is low, and a heating device for an automobile which does not excessively burden the battery. Can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a heating heat exchanger incorporated in a first example of an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a portion A in FIG.

FIG. 3 is a schematic perspective view showing an electric heater taken out.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a sectional view taken along the line CC in FIG.

FIG. 6 is a view similar to FIG. 5, showing a state in which the ends of the harness are connected.

FIG. 7 is a side view of the electric heater showing a specific shape of the resistor.

FIG. 8 is a circuit diagram of an electric heater.

FIG. 9 is a schematic diagram showing the entire configuration of a heating device for an automobile.

FIG. 10 is a flowchart showing an operation.

FIG. 11 is a diagram showing a start control state of the blower.

FIG. 12 is a diagram showing control of energization of an electric heater and operation speed control of a blower according to the temperature of blown air.

FIG. 13 is a schematic view showing the entire configuration of a vehicle heating device according to a second example of the embodiment of the present invention.

FIG. 14 is a schematic perspective view of an electric heater used in a second example.

FIG. 15 is a circuit diagram of an electric heater.

FIG. 16 is a schematic perspective view of an electric heater used in a third example of the embodiment of the present invention.

FIG. 17 is a schematic perspective view of an electric heater used in the fourth example.

FIG. 18 is a partial schematic cross-sectional view of the fifth example.

FIG. 19 is a perspective view of the sixth example.

FIG. 20 is a perspective view showing a conventional structure corresponding to a fifth example.

FIG. 21 is a perspective view of an essential part showing an example of a conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c Heating heat exchanger 2 Core part 3, 3a Heat transfer tube 4 Fin 5, 5a, 5b, 5c, 5d, 5e Electric heater 6 Cover member 7a, 7b Header 8 Inlet tube 9 Outlet tube 10 Sheet Plate 11a, 11b Header body 12 Insulator 13, 13a Resistor 14 Insulating layer 15 Adhesive 16 First terminal 17 Second terminal 18 Fuse 19 Harness 20 Protection tube 21 Insulation material 22 Duct 23 Blower 24 Evaporator 25 Bypass flow path 26 air mix door 27 defrost outlet 28 ventilation outlet 29 underfoot outlet 30 temperature sensor 31 controller 32 outside air temperature sensor 33 inside air temperature sensor 34 battery 35 battery sensor 36 engine 37 engine rotation sensor 38 water temperature sensor 39 air conditioning switch 40 cooling water pipe 41 alternator 42a, 42b, 42c relay switch 43 locking recess 44 a leaf spring 45 the capacitor 46 auxiliary heater

Claims (9)

[Claims] 1. A duct for circulating air for heating a vehicle cabin, a blower for blowing air into the duct, and a heating device provided in the duct for heating the air. A heat exchanger, and the heat exchanger for heating,
A pair of headers spaced apart from each other, a plurality of heat transfer tubes each having an opening at both ends communicating with these headers, and a core portion provided between the headers; In a heating device for an automobile, comprising an electric heater disposed between any of the heat transfer tubes constituting the core portion, the heating device is provided at a leeward side of the core portion in the duct. A temperature sensor that detects the temperature of the air that has passed through the core portion, and a controller that controls energization of the electric heater based on a detection signal of the temperature sensor, the controller has passed the core portion A heating device for a vehicle, wherein when the temperature of air is high, the amount of electricity to the electric heater is reduced or the electricity to the electric heater is stopped. 2. A detection signal of an outside air temperature sensor for detecting an outside air temperature is input to a controller, and the controller enables power supply to the electric heater only when the outside air temperature is lower than a predetermined value. 2. The heating device for an automobile according to 1. 3. A detection signal of an engine rotation sensor for detecting a rotation state of the engine is input to a controller, and the controller enables power supply to the electric heater only when the engine is rotating. An automotive heating device according to claim 1. 4. A detection signal of a battery sensor for detecting a remaining amount of a battery is input to a controller, and the controller enables power supply to the electric heater only when the remaining amount of the battery is equal to or more than a predetermined value. An automotive heating device according to any one of claims 1 to 3. 5. A signal representing an outlet for blowing air from the downstream end of the duct into the vehicle compartment is input to a controller, and the controller controls the electric heater only in a blowing state in which there is a possibility of performing warm air blowing. The heating device for a vehicle according to any one of claims 1 to 4, wherein the heating device enables electricity to be supplied. 6. A fluid flowing in each heat transfer tube constituting the heating heat exchanger is cooling water for an automobile engine, and a detection signal of a water temperature sensor for detecting a temperature of the cooling water is input to the controller. The heating device for a vehicle according to any one of claims 1 to 5, wherein the controller enables the power supply to the electric heater only when the temperature of the cooling water is lower than a predetermined value. 7. The vehicle heating apparatus according to claim 1, wherein the heating heat exchanger is a condenser constituting a heat pump cycle, and the fluid flowing through each heat transfer tube is refrigerant vapor. 8. The electric heater incorporated in the heating heat exchanger, wherein a thin film of a resistor is attached to a surface of an insulator, and the resistor is covered with an insulating layer. 2. A heating device for an automobile according to the item 1. 9. A locking recess is formed at both ends in the longitudinal direction of the electric heater, and an elastic member is mounted on inner surfaces of the pair of headers facing each other, and the elastic member and the locking recess are connected to each other. The heating device for a vehicle according to any one of claims 1 to 8, wherein the engagement prevents the electric heater from falling out of the core portion.