JP2007280902A - Electrical heater and air-conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize downsizing of an electrical heater by suppressing increase of diameter of an electric wire connected to a common electrode plate. <P>SOLUTION: The electrical heater has a heat radiating section by laminating in order a current flowing exothermic member 23, a heat exchange fin 22, and an electrode plate which contacts the current flowing exothermic member 23 and the heat exchange fin 22 and flows current to the current flowing exothermic member 23. Two terminal parts 24c are integrally formed at the common electrode plate 24a which flows current simultaneously to the two current flowing exothermic members 23, and electric wires 27 are respectively connected to these terminal part 24c. Thereby, since the current flowing in every one piece of electric wires 27 can be made small, without making large the diameter of the electric wire 27, the wiring space of the electric wires 27 can be made small and connectors to connect the electric wires 27 can be made small in size to make the whole heater small in size. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric heater that generates heat when supplied with electric power, and a vehicle air conditioner using the electric heater.

Conventionally, Patent Document 1 discloses an electric heater configured by laminating a plurality of layers of heat radiation fins, energizing heat generating members, and electrode plates for supplying power to the energizing heat generating members. In addition, the present applicant discloses in Patent Document 2 an air conditioner for a vehicle using such an electric heater as an auxiliary heater at the start of heating. In Patent Documents 1 and 2, a so-called PTC heater in which an energized heat generating member is configured with a positive temperature coefficient thermistor (PTC element) or the like is employed as an electric heater.
JP-A-7-19781 Japanese Patent No. 5-169967

  By the way, in the electric heaters of Patent Documents 1 and 2, as shown in the schematic configuration diagram of FIG. 5, the heat dissipating fins 22, the energizing heat generating members 23 and the electrode plates 24 a and 24 b are sequentially laminated. When three or more members 23 are laminated, as shown in the electric circuit diagram of FIG. 6, two electrode plates 24a (hereinafter referred to as common electrode plates) for energizing the two heat generating members 23 are generated.

  Such a current flowing through the common electrode plate 24a is approximately twice as large as a current flowing through an electrode plate (hereinafter referred to as a single electrode plate) 24b that is energized to one energization heating member 23, and therefore the common electrode plate 24a. Also in the electric wire connected to, a current twice as large as that of the electric wire connected to the single electrode plate 24b flows.

  For this reason, in order to reduce the calorific value of the electric wire connected to the common electrode plate 24a, it is necessary to reduce the electric resistance by making the wire diameter of the electric wire thicker than the electric wire connected to the single electrode plate 24b. is there. However, if the wire diameter of the electric wire connected to the common electrode plate 24a is increased, the wiring space is increased and the connecting connector between the common electrode plate 24a and the electric wire is increased, so that the electric heater 20 as a whole is large. It becomes a problem in that it becomes.

  In view of the above points, an object of the present invention is to reduce the size of an electric heater by suppressing an increase in diameter of an electric wire connected to a common electrode plate.

  In order to achieve the above object, the present invention provides an energization heating member (23) that generates heat by energization, a heat exchange member (22) that promotes heat dissipation of the energization heating member (23), an energization heating member (23), and heat. The electrode members (24a, 24b) that are in contact with the replacement member (22) and energize the energizing heat generating member (23) are sequentially laminated, so that there are at least three energizing heat generating members (23). An electric heater in which the energized heat generating member (23), the heat exchange member (22), and the electrode members (24a, 24b) are stacked, and two of the electrode members (24a, 24b) are energized heat generating members (23). An electric heater to which a plurality of electric wires (27) are connected is a first feature of the common electrode member (24a) energized simultaneously.

  According to this, since the plurality of electric wires (27) are connected to the common electrode member (24a), the current flowing through the electric wires (27) per one wire when the single electric wire (27) is connected. Can be reduced. Therefore, in order to suppress the heat generation of the electric wire (27) connected to the common electrode member (24a), it is not necessary to increase the diameter of the electric wire (27).

  As a result, the wiring space of the electric wire (27) can be reduced and the connecting connector for connecting the common electrode member (24a) and the electric wire (27) can be reduced, so that the electric heater as a whole can be reduced in size. .

  In the electric heater having the first feature, the common electrode member (24a) may have a plurality of terminal portions (24c) to which the electric wires (27) are connected. According to this, since the common electrode member (24a) has the terminal portion (24c), a plurality of electric wires (27) can be easily connected.

  In the electric heater having the first feature described above, the terminal portion (24c) may be formed integrally with the common electrode member (24a). According to this, even if the plurality of terminal portions (24c) are formed on the common electrode member (24a), the number of parts is not increased, and therefore the increase in the manufacturing cost of the electric heater can be suppressed.

  Furthermore, in order to form the terminal portion (24c) integrally with the common electrode member (24a), specifically, the common electrode member (24a) and the terminal portion (24c) may be formed by punching. Moreover, what is necessary is just to form a terminal part (24c) by bending a part of common electrode member (24a).

  In the electric heater having the first feature described above, the plurality of terminal portions (24c) may be arranged so as to protrude in directions substantially parallel to each other. According to this, since the front-end | tip parts of each terminal part (24c) do not spread in the direction which leaves | separates, size reduction of an electric heater can be achieved further.

  In the electric heater having the first feature described above, the plurality of terminal portions (24c) may be disposed so as to protrude in a direction substantially perpendicular to the longitudinal direction of the common electrode member (24a). According to this, when connecting an electric wire (27) to a plurality of terminal parts (24c), since it becomes difficult to interfere with a common electrode member (24a), it can connect easily.

  Moreover, in this invention, let the vehicle air conditioner provided with the electric heater (20) of the above-mentioned 1st characteristic be the 2nd characteristic. According to this, by using the electric heater (20) of the first feature described above as an auxiliary heater of the vehicle air conditioner, it is possible to configure a vehicle air conditioner equipped with an auxiliary heater that has immediate effect at the start of heating.

  Furthermore, due to the downsizing effect of the electric heater (20) of the first feature described above, the mountability when the electric heater (20) is mounted on the vehicle air conditioner is also improved.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

  1-4, one embodiment of the present invention will be described. FIG. 1 shows an electric heater 20 according to the present invention applied to a vehicle air conditioner. FIG. 1 is a schematic sectional view of an indoor air conditioning unit 1 of the vehicle air conditioner.

  The vehicle air conditioner is mounted on a vehicle (for example, a hybrid vehicle or a diesel engine vehicle) in which the engine cooling water temperature does not easily rise when the engine is started or a vehicle with a cold district specification. The electric heater 20 of the present invention is used as an auxiliary heater for heating the blown air.

  First, the indoor air conditioning unit 1 is disposed inside the instrument panel (instrument panel) at the forefront of the vehicle interior and has a resin case 2 that constitutes an outer shell. An air passage through which air flows toward the vehicle interior is formed inside the case 2, and an inside / outside air switching box 3 is disposed at the most upstream part of the air flow.

  The inside / outside air switching box 3 includes an inside air introduction port 4, an outside air introduction port 5, and an inside / outside air switching door 6. The inside air introduction port 4 is an introduction port for introducing inside air (vehicle compartment air) into the case 2, and the outside air introduction port 5 is an introduction port for introducing outside air (vehicle compartment outside air) into the case 2. The inside / outside air switching door 6 is disposed inside the inside / outside air switching box 5 so as to be rotatable, and is inside / outside air switching means driven by a servo motor (not shown).

  Specifically, depending on the rotational position of the inside / outside air switching door 6, an inside air mode for introducing inside air from the inside air introduction port 4, an outside air mode for introducing outside air from the outside air introduction port 5, and an inside air / Switch to outside air mode. FIG. 1 shows a state of the inside air mode, and the inside air is introduced into the case 2 as indicated by an arrow A.

  On the downstream side of the air flow in the inside / outside air switching box 5, an electric blower 7 that blows air toward the passenger compartment is disposed. The blower 7 rotates a known centrifugal multiblade fan 7a by an electric motor 7b to blow air in the direction of arrow B. On the downstream side of the air flow of the blower 7, an evaporator 8 that is a cooling heat exchanger for cooling the blown air is disposed.

  The evaporator 8 is one of elements constituting a refrigeration cycle (not shown), and as is well known, absorbs heat from the blown air blown by the blower 7 when the low-pressure refrigerant flowing into the evaporator 8 evaporates. To cool the blown air. On the downstream side of the evaporator 8, a heater core 9 for heating the air (cold air) after passing through the evaporator 8 is arranged.

  The heater core 9 is a heating heat exchanger that reheats the air (cold air) that has passed through the evaporator 8 using the engine coolant as a heat source (the engine coolant circuit is not shown). Further, a bypass passage 10 through which air (cold air) after passing through the evaporator 8 bypasses the heater core 9 and passes through the heater core 9 inside the case 2 is formed.

  In the vehicle air conditioner of the present embodiment, the electric heater 20 is disposed on the downstream side of the heater core 9. When the heater core 9 cannot sufficiently heat the air after passing through the evaporator 8 during the heating operation of the vehicle air conditioner, the electric heater 20 generates heat by being supplied with electric power from a control device (not shown), and after passing through the heater core 9. It is an auxiliary heater that heats the air. Details of the electric heater 20 will be described later.

  As specific control of the electric heater 20 by the control device, for example, the temperature of the engine coolant passing through the heater core 9 is detected, and when the engine coolant temperature is below a predetermined temperature, the heater core 9 evaporates. It may be determined that the air after passing through the vessel 8 is in a state where the air cannot be sufficiently heated, and the electric heater 20 may be supplied with electric power.

  An air mix door 11 is disposed between the evaporator 8 and the heater core 9. The air mix door 11 is rotatably disposed in the case 2 and is driven by a servo motor (not shown) so that its rotational position (opening) can be adjusted continuously.

  Therefore, depending on the opening degree of the air mix door 11, the amount of air passing through the heater core 9 and the electric heater 20 (the amount of hot air indicated by arrow C) and the amount of air passing through the bypass passage 10 (the amount of cold air indicated by arrow D) are as follows. The proportion is adjusted. The hot air (arrow C) and the cold air (arrow D) are mixed downstream of the heater core 9, the electric heater 20, and the bypass passage 10 and blown into the vehicle interior. Air temperature is adjusted.

  In the most downstream part of the air passage of the case 2, a defroster opening 12 for blowing conditioned air toward the front window glass of the vehicle, a face opening 13 for blowing conditioned air toward the face of the occupant, and A total of three types of openings, a foot opening 14 for blowing air-conditioned air toward the passenger's feet, are provided.

  A defroster door 15, a face door 16 and a foot door 17 are rotatably arranged in the upstream portions of these openings 12 to 14, and these doors 15 to 17 are connected to a common servo via a link mechanism (not shown). Opening and closing operation is performed by a motor (not shown). FIG. 1 shows a state of the foot / defroster mode in which the defroster door 15 and the foot door 17 are simultaneously opened.

  Next, the details of the electric heater 20 will be described with reference to FIGS. FIG. 2 is an overall perspective view showing a schematic configuration of the electric heater 20 of the present embodiment, and FIG. 3 is an exploded perspective view of the electric heater 20. Note that the up, down, left, and right arrows in FIG. 2 indicate directions in the mounted state. In addition, the electric heater 20 of the present embodiment includes a PTC element 23a described later, and is a so-called PTC heater.

  The electric heater 20 is in contact with the energization heat generating member 23 that generates heat by energization, the heat exchange fin 22 that is a heat exchange member that promotes heat dissipation of the energization heat generation member 23, and the energization heat generation by contacting the energization heat generation member 23 and the heat exchange fin 22. The heat radiating portion 25 is configured by sequentially laminating electrode plates 24 a and 24 b that are electrode members for energizing the member 23. In the present embodiment, the energization heat generating member 23, the heat exchange member 22, and the electrode members 24a and 24b are stacked so that there are four energization heat generation members 23. Therefore, the basic configuration is the same as the schematic configuration diagram of FIG.

  In addition, a load is applied from both ends in the stacking direction (vertical direction in FIG. 2) with a frame 21 having a spring portion (not shown) so that these stacked members are in good contact, and a direction orthogonal to the stacking direction (FIG. 2). Then, the housings 26a and 26b are fitted from the left and right direction.

  Further, as shown in FIG. 3, the energizing heat generating member 23 has a plurality of PTC elements 23a fitted in a resin frame 23b formed of a heat-resistant resin material (for example, polyamide synthetic fiber or polybutadiene terephthalate). It is composed.

  The PTC element 23a rapidly increases in temperature when energized. When the temperature reaches a predetermined temperature (Curie point), the electrical resistance value rapidly increases to limit the current and to have a self-temperature control function that suppresses heat generation. It is a thermistor.

  The heat exchange fins 22 are aluminum for corrugated fins 22a obtained by forming a thin aluminum plate into a corrugated shape, and for keeping the fins 22a in a certain shape and ensuring a contact area with the PTC element 23a and the electrode plates 24a and 24b. The plate 22b is joined by brazing.

  The electrode plates 24a and 24b are formed by punching a flat metal (brass, copper, etc.) having good electrical conductivity. The electrode plate 24a shown in FIG. 3 is a common electrode plate that energizes the two energization heat generating members 23 simultaneously, and two electric wires 27 are connected to the end in the longitudinal direction (the left end in FIGS. 2 and 3). Two terminal portions 24c are formed for this purpose.

  Since the basic configuration of the electric heater 20 of the present embodiment is the same as that in FIG. 5, the outermost electrode plate 24 b in the stacking direction (the vertical direction in FIG. 2) of the heat radiating portion 25 energizes one energizing heat generating member 23. It becomes a single electrode plate, and the other electrode plate 24a becomes a common electrode plate.

  The terminal portion 24c of the common electrode plate 24a is formed by bending a longitudinal end portion (left end portion in FIGS. 2 and 3) of the common electrode plate 24a into a U shape. That is, the terminal portion 24c is integrally formed with the common electrode plate 24a. Each terminal portion 24c protrudes in a direction substantially parallel to each other and protrudes in a direction substantially perpendicular to the longitudinal direction of the common electrode plate 24a.

  The housing 26 is a resin housing formed of the same resin material as that of the resin frame 23b. One end side (right end side in FIG. 2) the housing 26b only holds the heat exchange core part, but the other end side (see FIG. In the housing 26a on the left end side in FIG. 2, the terminal portions 24c provided on the electrode plates 24a and 24b pass through, and the electric wires 27 are respectively connected to the terminal portions 24c outside the housing 26a. Yes.

  In the above configuration, the operation of the electric heater 20 will be described. As described above, when the vehicle air conditioner performs the heating operation, the electric heater 20 is supplied with electric power from the control device and generates heat when the heater core 9 cannot sufficiently heat the air after passing through the evaporator 8. As a result, the air blown into the passenger compartment can be heated, so that the vehicle air conditioner of the present embodiment can perform an immediate heating operation.

  Furthermore, in the electric heater 20 of the present embodiment, as shown in FIG. 4, a plurality (specifically, two) are provided on the common electrode plate 24a in which about twice the current flowing in the single electrode plate 24b flows. Since the electric wires 27 are connected to each other, the current flowing through the electric wires 27 can be reduced as compared with the case where a single electric wire 27 is connected as in the electric heater 20 described in Patent Documents 1 and 2. Can do. FIG. 4 is an electric circuit diagram of the electric heater of the present embodiment.

  Therefore, it is not necessary to increase the diameter of the wire 27 in order to suppress the heat generation of the wire 27 connected to the common electrode plate 24a. As a result, it is possible to reduce the space for handling the electric wires 27 and to reduce the size of the connection connector between the common electrode plate 24a and the electric wires 27, so that the electric heater 20 as a whole can be reduced in size.

  Specifically, the details of the miniaturization effect will be described by comparing FIG. 2 with FIG. FIG. 8 is an overall perspective view of a conventional electric heater 20 to which the present invention is not applied. That is, it is an overall perspective view of the electric heater 20 in which one electric wire is connected to the common electrode plate 24a.

  As shown in FIG. 2, in the electric heater 20 of the present embodiment, since the electric wires 27 connected to the common electrode plate 24a are thinner than the conventional electric heater 20, the electrode plates 24a and 24b, the electric wires 27, The connector case 27c can be reduced in size, and the connector connected to the end of the electric wire 27 can also be reduced in size. Thereby, the electric heater 20 as a whole is miniaturized.

  Furthermore, in the electric heater 20 of this embodiment, since the plurality of terminal portions 24c are formed integrally with the common electrode plate 24a, a plurality of electric wires can be easily connected to the common electrode plate 24a, and a plurality of terminals can be connected. Since it is not necessary to increase the number of parts in order to form the part 24c, the manufacturing cost of the electric heater 20 is not increased.

  Further, since each terminal portion 24c is configured to protrude in a direction substantially parallel to each other, the size of the electric heater 20 can be reduced by avoiding the distal end portion of each terminal portion 24c from spreading away. Can be achieved. Moreover, since each terminal part 24c is comprised so that it may protrude in the substantially perpendicular | vertical direction with respect to the longitudinal direction of the common electrode plate 24a, when connecting the electric wire 27 to each terminal part 24c, it interferes with the common electrode plate 24a. Hard to connect and easy to connect.

  Furthermore, due to the downsizing effect of the electric heater 20 of the present invention, the mounting property when the electric heater 20 is mounted on the vehicle air conditioner is also improved.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows.

  (1) In the above-described embodiment, the two terminal portions 24c are formed on the common electrode plate 24a. However, the number of the terminal portions 24c may be pluralized. Further, the terminal portions of the single electrode plate 24b may be divided into n pieces, and the terminal portions 24c of the common electrode plate 24a may be divided into 2n pieces. In addition, since the connection connector connected to a terminal part is also divided by such a plurality of terminal parts, what is necessary is just to multiplex a terminal part in the range which does not impair the miniaturization effect of the electric heater 20. FIG.

  (2) In the above embodiment, the terminal portion 24c arranged in parallel in the stacking direction of the heat radiating portion 25 is formed by bending the end portion in the longitudinal direction of the common electrode plate 24a into a U shape. The part 24c may be formed by other methods. For example, as shown in FIG. 7, the common electrode plate 24a may be formed in advance so that the terminal portions 24c are arranged in parallel in the longitudinal direction of the common electrode plate 24a.

  (3) In the above-described embodiment, the electric heater 20 is disposed on the downstream side of the heater core 9, but a foot duct (not shown) that is disposed on the downstream side of the foot opening 14 and guides the conditioned air to the feet of the occupant. You may arrange in. Further, the electric heater 20 of the present invention may be incorporated in a part of the heat exchange core portion of the heater core 9.

  (4) The application of the electric heater 20 of the present invention is not limited to the vehicle air conditioner, and can be applied to various uses.

It is sectional drawing of the indoor air conditioning unit of the vehicle air conditioner of one Embodiment. It is a whole perspective view showing a schematic structure of an electric heater of one embodiment. It is a disassembled perspective view of the thermal radiation part of the electric heater of one Embodiment. It is an electric circuit diagram of the electric heater of one embodiment. It is a schematic block diagram of the electric heater of a prior art. It is an electric circuit diagram of the electric heater of a prior art. It is a disassembled perspective view of the thermal radiation part of the electric heater of other embodiment. It is a whole perspective view which shows schematic structure of the electric heater of a prior art.

Explanation of symbols

20 ... electric heater, 22 ... heat exchange fin, 23 ... electric heating member,
24a ... Common electrode plate, 24b ... Single electrode plate, 24c ... Terminal part, 27 ... Electric wire.

Claims (8)

An energization heating member (23) that generates heat when energized;
A heat exchange member (22) that promotes heat dissipation of the energization heating member (23);
The electrode members (24a, 24b) that are in contact with the energization heat generating member (23) and the heat exchange member (22) and energize the energization heat generation member (23) are sequentially laminated.
An electric heater in which the energized heat generating member (23), the heat exchange member (22), and the electrode members (24a, 24b) are laminated so that there are at least three energized heat generating members (23). There,
An electric heater characterized in that a plurality of electric wires (27) are connected to the common electrode member (24a) for simultaneously energizing the two energization heating members (23) among the electrode members (24a, 24b). . The electric heater according to claim 1, wherein the common electrode member (24a) has a plurality of terminal portions (24c) to which the electric wires (27) are connected. The electric heater according to claim 1 or 2, wherein the terminal portion (24c) is formed integrally with the common electrode member (24a). The electric heater according to claim 3, wherein the common electrode member (24a) and the terminal portion (24c) are formed by punching. The electric heater according to claim 3 or 4, wherein the terminal portion (24c) is formed by bending a part of the common electrode member (24a). The electric heater according to any one of claims 2 to 5, wherein the plurality of terminal portions (24c) are arranged so as to protrude in directions substantially parallel to each other. The plurality of terminal portions (24c) are arranged so as to protrude in a direction substantially perpendicular to the longitudinal direction of the common electrode member (24a). The electric heater according to 1. A vehicle air conditioner comprising the electric heater (20) according to any one of claims 1 to 7.

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