JP4450212B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner that is used in combination with a heating heat exchanger that uses hot water or the like as a heating heat source and an electric heating element as an auxiliary heat source, and is suitable for use in a vehicle air conditioner or the like.

  In recent years, as the efficiency of a vehicle engine increases, the coolant temperature (warm water) of the vehicle engine tends to be lower than that in the past even after the engine is warmed up. In particular, a diesel engine generally has a higher thermal efficiency than a gasoline engine, and thus the above tendency is remarkable. Therefore, in the hot water type air conditioner that heats the passenger compartment by using the waste heat from the engine cooling water, a lack of heating capacity is a problem.

Therefore, there is an air conditioner that solves the shortage of heating capacity by using a hot water heating heat exchanger and an electric heating element in combination, and heating the heating air by the heat generated by the electric heating element. In such an air conditioner, the applicant previously described in the following patent document, among the plurality of electric heating elements, increases the amount of heat generated by the electric heating element arranged at a part where the wind speed is high and the part where the wind speed is low. Discloses an air conditioner that reduces the amount of heat generated by an electrical heating element.
JP 2001-1751 A

  However, while the heating temperature of the electric heater by the electric heating element is uniform, the heating temperature of the hot water heater is lower on the hot water outlet side than on the hot water inlet side, so that there is a difference in the blowing temperature depending on the position. There is a point. In addition, for a hot water heater with such a gradient in the heat generation temperature distribution, simply assisting with a uniform heat generation temperature of the electric heater contributes to the lack of heating capacity, but the difference in blowing temperature depending on the position is In addition to being solved, there is a problem that the generated heat of the electric heating element is not effectively used for heating the passenger compartment depending on the position.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to eliminate the difference in blowing temperature depending on the position and to make the most effective use of the amount of heat generated by the electric heating element. Is to provide.

In order to achieve the above object, the present invention employs technical means described in claims 1 to 3. That is, in the invention described in claim 1, an air conditioning case (11) that forms an air passage, a heating heat exchanger (13) that heats air passing through the air conditioning case (11), and heating A plurality of energized heat generating portions (33A to 33D) for heating the air passing through the heating heat exchanger (13) arranged in parallel with the heating heat exchanger (13) on the downstream side of the air flow of the heat exchanger for heat use (13). In an air conditioner comprising an electric heater (30),
When the heating temperature of the heat exchanger for heating (13) is low at the time of air heating, power is supplied to the plurality of energized heat generating portions (33A to 33D) and the heating temperature of the heating heat exchanger (13) increases. In this case, the energization heat generating section (33A to 33D) corresponding to the portion where the heating temperature of the heat exchanger for heating (13) rises quickly is turned off sequentially.

  For example, when the vehicle is started and heating is started when it is cold, the plurality of energized heat generating portions (33A to 33D) of the electric heater (30) are energized to perform immediate heating, and the vehicle engine cooling water (warm water) ) When the temperature rises, the hot water is passed through the heating heat exchanger (13), and air heating can be performed in the heating heat exchanger (13). At this time, since the temperature of the hot water inlet (13a) rises faster than that of the hot water outlet (13b), the energization heat-generating parts (33A to 33D) corresponding to the heated portions are sequentially turned off. Become.

  According to the first aspect of the present invention, the electric heater (30) is passed by energizing the energization heat generating portion (33A to 33D) in accordance with the temperature gradient of the heating heat exchanger (13). The subsequent air temperature distribution can be made substantially uniform regardless of the passing position, and the temperature difference of the blown air depending on the position can be reduced. In addition, the amount of heat generated by the energized heat generating portions (33A to 33D) can be used to the maximum extent possible for heating the passenger compartment.

Moreover, in invention of Claim 2, the heat exchanger (13) for heating the air-conditioning case (11) which forms an air path, the air arrange | positioned in an air-conditioning case (11), and passing, A plurality of energized heat generating portions (33A to 33D) for heating the air passing through the heating heat exchanger (13) arranged in parallel with the heating heat exchanger (13) on the downstream side of the air flow of the heat exchanger for heat use (13). In an air conditioner comprising an electric heater (30),
When the heat generation temperature of the heating heat exchanger (13) decreases during air heating, it corresponds to the portion of the plurality of energized heat generating sections (33A to 33D) where the heat generation temperature of the heating heat exchanger (13) has decreased. It is characterized in that energization is sequentially performed from the energization heat generating section (33A to 33D).

  For example, if the vehicle is stopped when it is cold and heating at idling is continued for a long time, the cooling water (warm water) temperature of the vehicle engine decreases and the heating capacity becomes insufficient, and heating assistance with the electric heater (30) is necessary. In such a case, among the plurality of energization heat generating portions (33A to 33D), from the energization heat generation portions (33A to 33D) corresponding to the portion where the heat generation temperature of the heating heat exchanger (13) is reduced. Sequential energization is performed.

  Also according to the second aspect of the invention, after passing through the electric heater (30) by energizing the energizing heat generating portions (33A to 33D) in correspondence with the temperature gradient of the heat exchanger for heating (13). The air temperature distribution can be made substantially uniform regardless of the passing position, and the temperature difference of the blown air depending on the position can be reduced. In addition, the amount of heat generated by the energized heat generating portions (33A to 33D) can be used to the maximum extent possible for heating the passenger compartment.

  Moreover, in invention of Claim 3, in the air conditioner in any one of Claim 1 or Claim 2, the heat exchanger (13) for a heating is a warm water type heater (13), and a warm water exit (13b) ) Side is characterized in that the exothermic temperature is less likely to rise and the exothermic temperature tends to be lower than the hot water inlet (13a) side. According to the third aspect of the invention, the hot water heater (13) is likely to cause a temperature gradient between the hot water inlet (13a) side and the hot water outlet (13b) side. Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with the specific means described in the embodiments described later.

(First embodiment)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a structural outline of an air conditioning unit 1 of a vehicle air conditioner according to the first and second embodiments of the present invention, and shows a state of a defroster blowing mode. The ventilation system of the vehicle air conditioner according to the present embodiment is roughly divided into two parts: an air conditioning unit 1 and a blower unit (not shown).

  The vehicle of this embodiment is a hybrid vehicle, a diesel vehicle, or a gasoline vehicle, such as a vehicle that has high efficiency and is difficult to increase the engine water temperature, a cold region specification vehicle, etc. An electric heater (hereinafter referred to as a PTC heater) 30 is incorporated on the downstream side of the heater core (heating heat exchanger, hot water heater) 13 of the air conditioning unit 1.

  The blower unit is arranged offset from the central part to the passenger seat side in the lower part of the instrument panel in the passenger compartment, whereas the air conditioning unit 1 is substantially the left-right direction in the lower part of the instrument panel in the passenger compartment. Located in the center. As is well known, the blower unit is composed of an inside / outside air switching box for switching between the inside air (vehicle interior air) and the outside air (vehicle outside air) and a blower for blowing air introduced from the inside / outside air switching box. .

  This blower rotates a known centrifugal multiblade fan (sirocco fan) by a blower motor. The air conditioning unit 1 also integrally incorporates an evaporator (refrigerant evaporator) 12 as a cooling heat exchanger and a heater core 13 as a heating heat exchanger in one common air conditioning case 11. Of the type.

  The air conditioning case 11 is made of a resin molded product having some elasticity and excellent strength such as polypropylene, and is divided into a left and right divided case having a dividing surface in the vertical direction (vehicle vertical direction) in FIG. Become. This left and right split case accommodates equipment such as the heat exchangers 12 and 13 and doors 16, 21, and 25 described later, and is then integrally coupled by fastening means such as metal spring clips and screws to the air conditioning case 11. Configure.

  The air conditioning unit 1 is arranged in the posture shown in FIG. 1 with respect to the front-rear and up-down directions of the vehicle, and an air inlet 14 is disposed at a portion of the air-conditioning case 11 closest to the vehicle. Air conditioning air blown from the above-described blower unit flows into the air inlet 14. The air inflow port 14 is open to the side surface of the air conditioning case 11 on the passenger seat side in order to connect to the air outlet portion of the blower unit disposed in the front portion of the passenger seat.

  In the air conditioning case 11, the evaporator 12 is disposed at a position immediately after the air inlet 14 so as to cross the entire area of the air passage. As is well known, the evaporator 12 absorbs the latent heat of evaporation of the refrigerant in the refrigeration cycle from the air-conditioning air and cools the air-conditioning air. Here, as shown in FIG. 1, the evaporator 12 is installed in the air conditioning case 11 so as to be thin in the longitudinal direction of the vehicle and in the longitudinal direction in the vertical direction of the vehicle.

  Further, the evaporator 12 is a well-known laminated type, and a large number of laminated layers are formed by interposing corrugated fins in which a thin aluminum plate is formed into a wave shape between flat tubes formed by laminating two metal thin plates such as aluminum. Arranged and brazed together. A heater core 13 is disposed adjacent to the evaporator 12 on the downstream side of the air flow (the vehicle rear side) at a predetermined interval.

  The heater core 13 reheats the cold air that has passed through the evaporator 12, and is a hot water heater that heats high-temperature engine cooling water (hot water) through the inside thereof and heats the air using the cooling water as a heat source. As with the evaporator 12, the heater core 13 is also installed in the air conditioning case 11 so as to be thin in the vehicle front-rear direction and oriented in the longitudinal direction in the vehicle vertical direction.

  The heater core 13 is a well-known one, and a large number of corrugated fins in which a thin aluminum plate is formed into a wave shape are interposed between flat tubes formed by joining thin metal plates such as aluminum in a flat cross section by welding or the like. They are stacked and brazed together.

  In this embodiment, since the lower side is the hot water inlet side tank (hot water inlet) 13a and the upper side is the hot water outlet side tank (hot water outlet) 13b, a plurality of hot water flows into the lower hot water inlet side tank 13a. It is distributed to the flat tubes, heat-exchanged with the air-conditioning air through the corrugated fins and heated, and the cooled engine cooling water is gathered in the upper hot water outlet side tank 13b and flows out. Yes.

  In the air conditioning case 11, a cold air bypass passage 15 that bypasses the heater core 13 and flows air (cold air) is formed above the heater core 13. Further, in the air conditioning case 11, the air volume ratio between the warm air heated by the heater core 13 and the cool air that bypasses the heater core 13 (that is, cool air flowing through the cool air bypass passage 15) between the heater core 13 and the evaporator 12. A flat air mix door 16 is arranged to adjust the angle.

  Here, the air mix door 16 includes a rotating shaft 16a disposed in the horizontal direction and a plate portion 16b provided integrally with the rotating shaft 16a. The air mix door 16 rotates in the vehicle vertical direction together with the rotating shaft 16a. It is possible to move. The air mix door 16 constitutes temperature adjusting means for adjusting the air temperature by adjusting the air volume ratio.

  The rotating shaft 16a is rotatably supported by the air conditioning case 11, and one end of the rotating shaft 16a protrudes outside the air conditioning case 11 and is coupled to a link mechanism (not shown) to form a temperature control mechanism of the air conditioner. It is rotated by an actuator such as a motor.

  In the air conditioning case 11, a wall surface 17 extending in the vertical direction with a predetermined interval between the heater core 13 and the heater core 13 is integrally formed in the air conditioning case 11 on the air downstream side (the vehicle rear side portion) of the heater core 13. Yes. The wall surface 17 forms a hot air passage 18 that extends upward immediately after the heater core 13, and the downstream side (upper side) of the hot air passage 18 merges with the cold air bypass passage 15 in the upper portion of the heater core 13, A cool / warm air mixing space 19 for mixing with warm air is formed.

  On the upper surface of the air conditioning case 11, a defroster opening 20 is opened at a front portion of the vehicle. The defroster opening 20 allows the conditioned air whose temperature is adjusted from the cold / hot air mixing space 19 to flow in through the inlet hole 20a, which is the second inlet hole, and is connected to the defroster outlet through a defroster duct (not shown). The wind is blown out from the outlet toward the inner surface of the front window glass of the vehicle.

  In the air conditioning case 11, an inlet hole 23 that is a first inlet hole is formed, and a face opening 22 and an inlet hole 24 a that is a third inlet hole are formed in a space formed downstream of the inlet hole 23. Has been. The inlet hole 20 a and the inlet hole 23 are selectively opened and closed by the defroster door 21. That is, the defroster opening 20 and the inlet hole 23 are opened and closed by the defroster door 21. The defroster door 21 includes a rotating shaft 21a that is rotatably supported by the air conditioning case 11, and a plate portion 21b that is provided integrally with the rotating shaft 21a.

  A foot opening 24 is provided on the downstream side of the inlet hole 24a. The face opening 22 and the entrance hole 24 a are selectively opened and closed by a foot / face switching door 25. That is, the face opening 22 and the foot opening 24 are opened and closed by the foot / face switching door 25. The foot / face switching door 25 includes a rotating shaft 25a rotatably supported by the air conditioning case 11, and a plate portion 25b provided integrally with the rotating shaft 25a.

  The defroster door 21 and the foot / face switching door 25 are blowing means switching door means, which are connected to a link mechanism (not shown) and are operated in conjunction by an actuator such as a servo motor as the blowing mode switching mechanism. ing. The face opening 22 includes a center face outlet that is disposed on the upper side of the central part in the left and right direction of the instrument panel via a face duct (not shown), and a side face that is disposed on the upper side of the left and right ends of the instrument panel. It is connected to the air outlet.

  Wind blows out from the center face outlet toward the occupant's head in the passenger compartment, and blows out from the side face outlet toward the occupant's head or the vehicle side window glass on the left and right sides of the passenger compartment. As is well known, the side face air outlet is equipped with a manually operated air outlet grille, and by adjusting the direction of the louvers of this air outlet grille, It is possible to blow wind toward the side window glass.

  The foot opening 24 is connected to a foot outlet through a foot duct (not shown) so as to blow warm air from the foot outlet toward the passenger's feet. In addition, as for each door 16,21,25 mentioned above, the length of each rotating shaft 16a * 21a * 25a is substantially the same. Each of the plate portions 16b, 21b, and 25b has a resin or metal door substrate, and has a structure in which an elastic sealing material such as urethane foam is attached to both front and back surfaces of the substrate.

  Next, the structure of the PTC heater 30 which concerns on the principal part of this invention is demonstrated. The PTC heater (auxiliary heater) 30 of the present embodiment is arranged downstream of the heater core 13 in the air conditioning case 11 so as to be arranged in parallel with the heater core 13, and the air blown from the upstream side of the heater core 13. Air can be blown to the downstream side of the PTC heater 30.

  FIG. 2 is a perspective view showing a schematic configuration of the PTC heater 30, and FIG. 3 is a schematic configuration diagram of a heat exchange core portion of the PTC heater 30 of FIG. The PTC heater 30 heat-exchanges by sequentially laminating an energization heating element array (energization heating unit) 33 as an energization heating unit, a heat exchange fin structure 32 as a heat exchange member, and an electrode plate 34 as an electrode member. It constitutes the core part. In addition, the PTC heater 30 of this embodiment has four energization heating element rows 33, which are 33A to 33D from above when mounted on the vehicle.

  A portion corresponding to a conventional common electrode is made into two electrode plates 24, and an insulating member 35 is laminated between the adjacent electrode plates 24 to achieve insulation. Since the insulating member 35 is made of, for example, a polyimide resin film that is thin and heat resistant, there is no significant effect on the space.

  Then, in order to make good contact between the laminated members, the frame 31 having spring portions (not shown) is pressed from both ends in the lamination direction, and the housing 36 is taken from a direction orthogonal to the lamination direction (substantially left-right direction in FIG. 2). It is held by fitting. 4A is a plan view of the PTC heater 30 energization heating element array 33 in FIGS. 2 and 3, and FIG. 4B is a partial perspective view of the heat exchange core portion.

  As shown in FIG. 4, the energization heating element array 33 includes a PTC element 331 having a positive resistance temperature characteristic as a plurality of electric heating elements, a resin material having heat resistance (for example, 66 nylon, polybutadiene terephthalate, etc.). It is fitted and held in the resin frame 332 formed by the above method.

  In addition, the heat exchange fin assembly 32 maintains a corrugated fin 32a obtained by forming a thin aluminum plate into a corrugated shape and the fin 32a in a fixed shape, and also ensures a contact area with the PTC element 33a and the electrode plate 34. The aluminum plate 32b is brazed and joined.

  The housing 36 is a resin housing formed of the same resin material as that of the resin frame 33b. The one end side housing 36B only holds the heat exchange core portion, but the other end side housing 36A is an electrode plate. The terminal part provided in 34 penetrates and forms the connector part C on the outer surface side. FIG. 5 is a schematic circuit diagram of the PTC heater 30 of FIG. 37 is a fuse for protecting from overcurrent, and 38 is an energization switch for energizing each energization heating element array 33 in sequence.

  As is well known, the vehicular air conditioner having such a configuration is an electronic device (not shown) to which operation signals from various operation members provided on an air conditioning operation panel (not shown) and sensor signals from various sensors for air conditioning control are input. A control device is provided, and a compressor (refrigerant compressor), a condenser (refrigerant condenser) fan, a blower motor, and the like (not shown) are driven and controlled by the output signal of the control device, and the positions of the doors 16, 21, 25 are controlled. The energization heating element rows 33A to 33D are energized and controlled as necessary.

  FIG. 6 is a graph showing that the energization heating element array 33 of the PTC heater 30 in the first embodiment of the present invention is sequentially turned off. When the heat generation temperature of the heater core 13 is low at the time of air heating, the heat generation temperature of the heater core 13 is increased while energizing the plurality of energization heat generating element arrays 33A to 33D. Then, the energization heating element rows 33A to 33D corresponding to the portions where the heat generation temperature of the heater core 13 rises quickly is sequentially turned off.

  For example, when the vehicle is started and heating is started when it is cold, the plurality of energized heating element rows 33A to 33D of the PTC heater 30 are energized to perform immediate heating. For example, in the state of the defroster blowing mode in FIG. 1, the air heated by the PTC heater 30 is blown toward the inner surface of the vehicle front window glass, and immediate effect and clouding are performed.

  When the temperature of the cooling water (warm water) of the vehicle engine rises, the warm water is passed through the heater core 13 so that the heater core 13 can perform air heating. At this time, since the temperature rise on the warm water inlet tank 13a side of the heater core 13 is quicker than that on the warm water outlet tank 13b side, the energization heating element rows 33A to 33D corresponding to the heated portions are sequentially turned off. Become.

  According to this, it is possible to make the air temperature distribution after passing through the PTC heater 30 substantially uniform regardless of the passing position by energizing the energizing heating element rows 33A to 33D in correspondence with the temperature gradient of the heater core 13. The temperature difference of the blown air depending on the position can be reduced. For example, in the case of the above-described defroster blowout, the fog on the front window glass of the vehicle is uniformly cleared. In addition, the amount of heat generated by the energized heat generating element rows 33A to 33D can be used to the maximum extent possible for heating the passenger compartment.

  The heater core 13 is a hot water heater 13, and the hot water outlet 13b side is a portion where the heat generation temperature is less likely to rise compared to the hot water inlet 13a side. This is because the warm water heater 13 tends to generate a temperature gradient between the warm water inlet 13a side and the warm water outlet 13b side.

(Second Embodiment)
FIG. 7 is a graph showing that the energized heating element array 33 of the PTC heater 30 is sequentially turned on in the second embodiment of the present invention. As a feature different from the first embodiment described above, when the heat generation temperature of the heater core 13 decreases during air heating, the heat generation corresponding to the portion where the heat generation temperature of the heater core 13 decreases among the plurality of power generation element arrays 33A to 33D. Power is sequentially supplied from the element rows 33A to 33D.

  For example, if the vehicle is stopped when it is cold and heating at idling is continued for a long time, the cooling water (warm water) temperature of the vehicle engine decreases, the heating capacity becomes insufficient, and heating assistance by the PTC heater 30 is necessary. In such a case, energization heating element rows 33A to 33D corresponding to portions of the plurality of energization heating element rows 33A to 33D corresponding to the portions where the heat generation temperature of the heater core 13 is lowered are sequentially energized.

  Also by this, by energizing the energization heating element rows 33A to 33D in correspondence with the temperature gradient of the heater core 13, the air temperature distribution after passing through the PTC heater 30 can be made substantially uniform regardless of the passing position. The temperature difference of the blown air due to can be reduced. In addition, the amount of heat generated by the energized heat generating element rows 33A to 33D can be used to the maximum extent possible for heating the passenger compartment.

  In this case, the heater core 13 is also a hot water heater 13, and the hot water outlet 13b side is a portion where the heat generation temperature tends to be lower than the hot water inlet 13a side. This is because the warm water heater 13 tends to generate a temperature gradient between the warm water inlet 13a side and the warm water outlet 13b side.

(Other embodiments)
Although the number of PTC heaters 30 is one in the above-described embodiment, the present invention is not limited to the above-described embodiments, and a plurality of PTC heaters 30 may be used. In addition, although there are four energized heat generating element arrays, this number is not limited. In the embodiment of FIGS. 6 and 7, all of the four energized heat generating element arrays 33A to 33D are turned off at regular intervals. Although all of them are turned on, it is not always necessary to energize all the energized heating element arrays, and the ON / OFF intervals need not be constant. Further, the energization heating element 33a is not limited to the PTC element.

It is sectional drawing which shows the structure outline | summary of the air conditioning unit 1 of the vehicle air conditioner which concerns on 1st, 2nd embodiment of this invention. It is a perspective view which shows the schematic structure of the PTC heater 30 in FIG. It is a schematic diagram which shows schematic structure of the PTC heater 30 heat exchange core part of FIG. (A) is a top view of the PTC heater 30 conduction | electrical_heating heating element row | line | column 33 of FIG. 2, FIG. 3, (b) is a fragmentary perspective view of a heat exchange core part. It is a schematic circuit diagram of the PTC heater 30 of FIG. It is a graph which shows turning off the energization heat generating element row | line | column 33 of the PTC heater 30 in 1st Embodiment of this invention sequentially. It is a graph which shows turning ON the energization heat generating element row | line | column 33 of the PTC heater 30 in 2nd Embodiment of this invention sequentially.

Explanation of symbols

11 ... Air conditioning case 13 ... Heater core (heat exchanger for heating, hot water heater)
13a ... Warm water inlet side tank (hot water inlet)
13b ... Warm water outlet side tank (warm water outlet)
30 ... PTC heater (electric heater)
33A to 33D ... energization heating element array (energization heating part)

Claims (3)

An air conditioning case (11) forming an air passage;
A heating heat exchanger (13) for heating the air passing through the air conditioning case (11);
A plurality of energizing heat generating portions (33A to 33D) for heating the air passing through the heating heat exchanger (13) arranged downstream of the air flow of the heating heat exchanger (13 ). In an air conditioner comprising an electric heater (30) having
When the heating temperature of the heating heat exchanger (13) is low during air heating, the plurality of energized heating sections (33A to 33D) are energized and the heating temperature of the heating heat exchanger (13). When the air temperature rises, the air-conditioning apparatus is characterized in that the energization heat generating section (33A to 33D) corresponding to a portion where the heat generation temperature of the heating heat exchanger (13) rises quickly is turned off sequentially. An air conditioning case (11) forming an air passage;
A heating heat exchanger (13) for heating the air passing through the air conditioning case (11);
A plurality of energizing heat generating portions (33A to 33D) for heating the air passing through the heating heat exchanger (13) arranged downstream of the air flow of the heating heat exchanger (13 ). In an air conditioner comprising an electric heater (30) having
When the heat generation temperature of the heating heat exchanger (13) decreases during air heating, the portion of the plurality of energized heat generation sections (33A to 33D) where the heat generation temperature of the heating heat exchanger (13) decreases The air conditioner is characterized in that energization is sequentially performed from the energization heat generating portions (33A to 33D) corresponding to the above.   The heating heat exchanger (13) is a hot water heater (13), and the heating water outlet (13b) side is less likely to raise the heating temperature than the warm water inlet (13a) side, and the heating temperature is likely to fall. The air conditioner according to any one of claims 1 and 2, wherein the air conditioner is.

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