JP6105275B2 - Air conditioner for vehicles - Google Patents

Description

  The present invention relates to a vehicle air conditioner mounted on, for example, an automobile, and particularly relates to a technical field for controlling an electric heater.

  Conventionally, for example, an electric heater having a heating element such as a PTC element is used as a heating heat source of a vehicle air conditioner (see, for example, Patent Document 1). The air conditioner of Patent Document 1 includes a casing that houses an electric heater, a blower fan, various dampers, and the like. Hot air can be obtained by heating the air-conditioning air introduced into the casing with an electric heater.

  In the air conditioner of Patent Document 1, the electric heater is provided with three types of heating elements having different heating values. A heating element with a high calorific value is arranged in a part with a high wind speed in the casing, and a heating element with a low calorific value is arranged in a part with a low wind speed. Thereby, it is preventing that the air temperature of the low wind speed site | part in a casing rises too much.

JP 2001-1751 A

  By the way, in the configuration in which three types of heating elements are provided in one electric heater as in the electric heater of Patent Document 1, when only one heating element is energized according to the required heating capacity, two heating elements are generated. When energizing the body, all the heating elements may be energized. The required heating capacity may change during heating. For example, when only one heating element is energized, two heating elements are energized, or when two heating elements are energized, If the heating element is energized, the heating capacity will increase step by step, so the temperature difference between the conditioned air blown out of the casing before and after the switching of the heating capacity will increase, and the passenger will feel uncomfortable and the comfort will be impaired. End up. When the heating capacity is lowered, the same problem occurs because the heating capacity is lowered step by step.

  The present invention has been made in view of such a point, and an object of the present invention is to blow out air before and after switching of the heating capacity when using an electric heater configured to switch the heating capacity in multiple stages. It is intended to prevent the passenger from feeling a sense of incongruity by preventing the temperature of the vehicle from changing greatly, and to improve comfort.

  In order to achieve the above object, the present invention utilizes the fact that the wind speed is not uniform in the casing, for example, even when energizing one heating element, by selecting the position of the heating element to be energized. The change in capacity was made small before and after switching the heating capacity.

The first invention includes an electric heater configured to heat external air passing through the first heating element , the second heating element, and the third heating element that generate heat when power is supplied.
An evaporator for cooling external air passing therethrough,
A casing having a hot air passage and a cold air passage in which the electric heater and the evaporator are respectively disposed, and an air mix space communicating with the downstream side of the hot air passage and the cold air passage ;
An air mix damper that is accommodated in the casing and changes the amount of hot air and the amount of cold air flowing into the air mix space by opening and closing the hot air passage and the cold air passage; and
An air conditioning control device for controlling the electric heater and the air mix damper ,
The conditioned air introduced into the casings grayed, in vehicle air-conditioning system configured to supply to each part of the passenger compartment from is passed through the electric heater and the evaporator,
The first heating element is disposed at a part where the wind speed is lower than the arrangement part of the second heating element in the warm air passage ,
The third heating element is arranged at a portion where the wind speed is higher than the arrangement portion of the second heating element in the warm air passage,
The air conditioning control device calculates a target opening of the hot air passage of the air mix damper, and when the target opening is a large opening that requires high heating capacity, the second heating element and the above Electric power is supplied to the third heating element and power is not supplied to the first heating element, and the target opening is within the range of the medium opening of the heating capacity that is lower than the large opening to the large opening. When the opening is on the large opening side, power is supplied only to the third heating element, and the target opening is within the range of the medium opening from the large opening side of the medium opening and When the heating capacity is low and the opening is on the small opening side, electric power is supplied only to the second heating element, and the target opening is lower than the intermediate opening from the intermediate opening. if it becomes small opening degree of der those characterized by being configured for supplying power only to the first heating element .

According to this arrangement, it is possible to reduce the temperature change of the blown out air.

A second invention includes an electric heater configured to heat external air passing through the first heating element, the second heating element, and the third heating element that generate heat when power is supplied.
An evaporator for cooling external air passing therethrough,
A casing having a hot air passage and a cold air passage in which the electric heater and the evaporator are respectively disposed, and an air mix space communicating with the downstream side of the hot air passage and the cold air passage;
An air mix damper that is accommodated in the casing and changes the amount of hot air and the amount of cold air flowing into the air mix space by opening and closing the hot air passage and the cold air passage; and
An air conditioning control device for controlling the electric heater and the air mix damper,
In the vehicle air conditioner configured to supply the air conditioning air introduced into the casing to each part of the passenger compartment after passing through the electric heater and the evaporator,
The first heating element is disposed at a part where the wind speed is lower than the arrangement part of the second heating element in the warm air passage,
The third heating element is arranged at a portion where the wind speed is higher than the arrangement portion of the second heating element in the warm air passage,
The air conditioning control device calculates a target opening degree of the hot air passage of the air mix damper, and when the target opening degree is a small opening degree that requires a low heating capacity, When only the power is supplied and the target opening is within the range of the medium opening of the heating capacity higher than that at the small opening from the small opening, and the opening is on the small opening side, Electric power is supplied only to the second heating element, and the target opening is an opening from the small opening side of the intermediate opening to the large opening side within the range of the intermediate opening and the heating capacity is high. In this case, power is supplied only to the third heating element, and the second heat generation is performed when the target opening is a large opening having a heating capacity higher than the intermediate opening from the intermediate opening. der which the body and supplies power to the third heating element, characterized in that it is configured to the non-supply of power to the first heating element .

According to this arrangement, it is possible to reduce the temperature change of the blown out air.

According to the first invention, the it is possible to ensure that the passenger does not feel uncomfortable to prevent the temperature of the blown air before and after the switching of the warm tufts capacity greatly changes, thereby enhancing comfort Can do.

According to the second invention, it is possible to further reduce the temperature change in the outlet air when reducing the warm tufts capability.

It is sectional drawing which shows the internal structure of the vehicle air conditioner which concerns on embodiment. It is a front view of an electric heater. It is a block diagram of a vehicle air conditioner. It is a flowchart which shows the control content by the air-conditioning control apparatus in the case of reducing heating capability. It is a flowchart which shows the control content by the air-conditioning control apparatus in the case of making heating capacity increase.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  FIG. 1 is a cross-sectional view of a vehicle air conditioner 1 according to an embodiment of the present invention. The vehicle air conditioner 1 is accommodated, for example, in an instrument panel (not shown) provided in the front part of a passenger compartment of an automobile.

  In the description of this embodiment, for convenience of explanation, the front side of the vehicle is simply referred to as “front”, the rear side of the vehicle is simply referred to as “rear”, the left side of the vehicle is simply referred to as “left”, and the right side of the vehicle is referred to. Is simply called “right”.

  The vehicle air conditioner 1 includes an air conditioning unit 2 and an air conditioning control device 3. The air conditioning unit 2 includes a blower fan 10, an evaporator 11 as a cooling heat exchanger, an electric heater 12, an air mix damper 13, a heat damper 14, a differential / vent switching damper 15, and a casing 16. The evaporator 11, the electric heater 12, the air mix damper 13, the heat damper 14, and the differential / vent switching damper 15 are accommodated in a casing 16.

  The casing 16 is formed by molding a resin material or the like, for example. A fan housing 20 that houses the blower fan 10 is formed on the upper portion of the casing 16. The blower fan 10 is driven by a blower motor 10a. The blower motor 10 a is controlled by the air conditioning control device 3. The evaporator 11 and the electric heater 12 are accommodated below the fan housing 20.

  Although not shown, the fan housing 20 is provided with an inside / outside air switching box for switching between air inside the vehicle compartment and air outside the vehicle compartment. Air-conditioning air introduced from the inside / outside air switching box is introduced into the fan housing 20.

  A defroster port 22 and a vent port 23 are formed in the upper portion of the fan housing 20 of the casing 16. Further, a heat port 24 is formed in the lower rear portion of the casing 16.

  The defroster port 22 is connected to a defroster outlet of the instrument panel via a defroster duct (not shown), and is mainly for supplying conditioned air to the inner surface of the front window. The vent port 23 is connected to a vent outlet of the instrument panel via a vent duct (not shown), and is mainly for supplying conditioned air to the upper body of the occupant. The vent outlets are respectively provided on the left and right sides and the center of the instrument panel. The heat port 24 is for supplying conditioned air to a passenger's feet through a foot duct (not shown). The foot duct may extend not only to the front seat but also to the rear seat.

  An air flow path R is formed in the casing 16. The air flow path R includes a cold air passage R1 extending from the fan housing 20, a hot air passage R2 extending from a downstream end of the cold air passage R1, and extending downward, an upper side of the downstream end of the cold air passage R1, and a downstream of the hot air passage R2. An air mix space R3 having an end communicating therewith, an upper passage R4 communicating with the air mix space R3 and extending upward, and a lower passage R5 communicating with the air mix space R3 and extending downward are formed.

  The cold air passage R <b> 1 extends rearward from the front side of the casing 16, and the evaporator 11 is disposed in the middle portion. The evaporator 11 generates cold air. The evaporator 11 constitutes a refrigerant evaporator of a refrigeration cycle apparatus, and is a tube-and-fin type heat exchanger having a plurality of tubes and fins. The evaporator 11 is disposed so that the tube extends in the vertical direction and crosses the cold air passage R1. Almost all of the air conditioning air introduced into the casing 16 passes through the evaporator 11.

  A drain portion 16 a for draining the condensed water generated in the evaporator 11 is provided on the bottom wall portion of the casing 16.

  The cool air passage R1 generates cool air when the compressor of the refrigeration cycle apparatus is operating, and does not generate cool air when the compressor is stopped. It will be called a cold air passage R1.

  The warm air passage R2 is formed in the lower half of the rear side inside the casing 16. The upstream end of the warm air passage R <b> 2 is located in the middle portion of the casing 16 in the vertical direction. A bulging portion 16 b that bulges upward (inside the casing 16) is formed at the boundary between the cold air passage R <b> 1 and the hot air passage R <b> 2 on the bottom wall portion of the casing 16.

  The warm air passage R2 has a U-turn on the downstream side and extends obliquely forward toward the upper side. An electric heater 12 is disposed in the middle of the hot air passage R2. The hot air passage R <b> 2 is a passage for generating hot air by the electric heater 12. Almost all of the air flowing through the hot air passage R2 passes through the electric heater 12, and the electric heater 12 is inclined so that the upper part is located behind the lower part.

  As shown in FIG. 2, the electric heater 12 includes an upper heating element 31, an intermediate heating element 32, a lower heating element 33, and a fixing member 34 that integrates them. The upper heating element 31 is formed by alternately arranging a plurality of PTC elements 31a and a plurality of fins 31b in the vertical direction. The fins 31b can be composed of corrugated fins, for example, and allow external air to circulate. Hot air is generated by heating the external air passing through the fins 31b by the heat of the PTC element 31a. The intermediate heating element 32 is also formed by alternately arranging a plurality of PTC elements 32a and fins 32b. The lower heating element 33 is also formed by alternately arranging a plurality of PTC elements 33a and fins 33b.

  The PTC elements 31a, 32a, and 33a of the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 are controlled by the air conditioning control device 3 as will be described in detail later. By supplying electric power to the PTC elements 31a, 32a, and 33a, the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 generate heat. In this embodiment, the amount of heat generated per unit time when the same power is supplied to the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 is set to be approximately equal.

  As indicated by phantom lines in FIG. 1, the cross section X of the portion of the hot air passage R <b> 2 where the electric heater 12 is disposed has an upper portion located behind the lower portion in the same manner as the inclination angle of the electric heater 12. Inclined to do. The wind speed distribution in the cross section X is the fastest in the vertical middle part of the cross section X, the slowest in the lower part of the cross section X, and the upper part of the cross section X in the vertical direction as indicated by the white arrow in the figure. The wind speed is between the section and the bottom.

  The reason why the wind speed in the lower part in the cross section X of the hot air passage R2 is the slowest is that the bulging portion 16b is formed in the bottom wall portion of the casing 16, and the cold air in the cold air passage R1 does not easily flow to the lower part in the cross section X. Because. The reason why the wind speed at the intermediate portion in the vertical direction in the cross section X is the fastest is that the center line of the hot air passage R2 is located and the main stream passes as shown by the solid line arrow. The reason why the upper wind speed in the cross section X is slower than the middle part in the vertical direction is that it is close to the inner wall of the hot air passage R2 and the air mix damper 13 described later rotates. Since there is no obstacle like 16b, the wind speed is faster than the lower part of the cross section X.

  The upper heating element 31 of the electric heater 12 is positioned above the cross section X of the hot air passage R2. Further, the intermediate heating element 32 is located in the middle in the vertical direction of the cross section X of the hot air passage R2. Further, the lower heating element 33 is located below the cross section X of the hot air passage R2. Since the wind speed distribution of the cross section X of the hot air passage R2 is set as described above, the lower heating element (first heating element) 33 of the electric heater 12 is the upper heating element (second heating element) in the hot air passage R2. Body) 31 and the intermediate heating element 32 are arranged at a part where the wind speed is lower than the arrangement part. Further, the intermediate heating element 32 (third heating element) is disposed at a location where the wind speed is higher than the arrangement location of the upper heating element 31 in the warm air passage R2.

  For this reason, among the upper heating element 31, the intermediate heating element 32, and the lower heating element 33, the amount of air per unit time passing through the intermediate heating element 32 is the largest, and per unit time passing through the lower heating element 33. The amount of air is the smallest. Therefore, when comparing the case where power is supplied only to the upper heating element 31, the case where power is supplied only to the intermediate heating element 32, and the case where power is supplied only to the lower heating element 33, the intermediate heating element 32 is compared. When the electric power is supplied only to the heating element, the heating capacity is the highest, and when the electric power is supplied only to the lower heating element 33, the heating capacity is the lowest.

  An upper holding portion 27 that holds the upper portion of the electric heater 12 is provided in the vicinity of the central portion in the vertical direction inside the casing 16. A partition wall 28 for partitioning the warm air passage R2 and the lower passage R5 is provided behind the upper holding portion 27 in the casing 16. The partition wall 28 extends upward from the rear side of the lower wall portion of the casing 16 and forms a downstream portion of the hot air passage R2 with respect to the electric heater 12. The substantially lower half of the partition wall 28 is inclined so as to be located later as it goes upward, while the substantially upper half is inclined so as to be located forward as it goes upward. By forming the partition wall 28 in this way, the warm air after passing through the electric heater 12 in the warm air passage R2 flows upward and obliquely forward.

  The air mix space R3 is located above the warm air passage R2 inside the casing 16, and is a space for mixing warm air and cold air to generate conditioned air.

  The upstream end opening 41 of the upper passage R4 communicates with the upper portion of the air mix space R3. The upper passage R4 extends upward, and the downstream side of the upper passage R4 branches in the front-rear direction. A defroster port 22 is formed on the front side downstream of the upper passage R4, and a vent port 23 is formed on the rear side.

  The upstream end opening 42 of the lower passage R5 communicates with the rear portion of the air mix space R3, and is located on the rear side of the upstream end opening 41 of the upper passage R4. That is, the upstream end opening 41 of the upper passage R4 and the upstream end opening 42 of the lower passage R5 are adjacent to each other. The lower passage R5 extends downward, and a heat port 24 is formed at the downstream end.

  The air mix damper 13 is for adjusting the temperature of the conditioned air by changing the amount of cool air and the amount of hot air flowing into the air mix space R3. The air mix damper 13 has a turning shaft 13a extending in the left-right direction and a turning shaft 13a. And a closing plate portion 13b extending in the radial direction.

  The rotation shaft 13 a is supported so as to be rotatable around a center line extending in the left-right direction with respect to the side wall portion of the casing 16. An actuator 4 disposed outside the casing 16 is connected to the rotation shaft 13a. The actuator 4 is controlled by the air conditioning control device 3.

  The rotation shaft 13 a of the air mix damper 13 is located in the vicinity of the front portion of the upper holding portion 27. The closing plate portion 13b swings in the vertical direction by the rotation of the rotation shaft 13a.

  When the blocking plate portion 13b swings upward, it closes the upper portion of the downstream end of the cold air passage R1 and opens the upstream end of the hot air passage R2. When the closing plate portion 13b closes the upper portion of the downstream end of the cold air passage R1, the cold air does not flow from the cold air passage R1 into the air mix space R3, and the cold air in the cold air passage R1 flows into the hot air passage R2 and is heated. Since the air flows into the air mix space R3, heating can be performed.

  On the other hand, when the blocking plate portion 13b swings downward, it closes the upstream end of the hot air passage R2 and opens the upper portion of the downstream end of the cold air passage R1. When the closing plate portion 13b closes the upstream end of the hot air passage R2, the cold air does not flow into the hot air passage R2 from the cold air passage R1, and the cold air in the cold air passage R1 flows into the air mix space R3. It can be performed. That is, the amount of cold air and the amount of hot air flowing into the air mix space R3 are changed according to the rotation angle of the air mix damper 13.

  The heat damper 14 is rotatably supported on the side wall portion of the casing 16 via a support shaft extending in the left-right direction. The heat damper 14 can be in a state where one of the upstream end opening 41 of the upper passage R4 and the upstream end opening 42 of the lower passage R5 is closed and the other is opened, or both are opened. It has become.

  When the upstream end opening 41 of the upper passage R4 is opened and the upstream end opening 42 of the lower passage R5 is closed, a blowing mode in which conditioned air mainly flows to the upper passage R4 is set. In this blowing mode, the conditioned air may be slightly leaked into the lower passage R5, or the entire amount may be allowed to flow into the upper passage R4.

  On the other hand, although not shown, when the upstream end opening 41 of the upper passage R4 is closed and the upstream end opening 42 of the lower passage R5 is opened, a blow-out mode in which conditioned air flows to the lower passage R5 is set. Further, when both the upstream end opening 41 of the upper passage R4 and the upstream end opening 42 of the lower passage R5 are opened, a blow mode is set in which conditioned air flows to the upper passage R4 and the lower passage R5.

  The differential / vent switching damper 15 is for switching the blowing mode by closing one of the defroster port 22 and the vent port 23 and opening the other, and is provided on the side wall portion of the casing 16 via a support shaft extending in the left-right direction. It is rotatably supported. The differential / vent switching damper 15 and the heat damper 14 are interlocked by a link mechanism. The heat damper 14 and the differential / vent switching damper 15 may be operated by an actuator, or may be operated by an occupant operating an operation wire.

  The movement of the heat damper 14 and the differential / vent switching damper 15 can be set by the shape of the cam of a known link mechanism. In this embodiment, the heat damper 14 closes the lower passage R5 and the differential / vent switching damper 15 closes the defroster port 22, the heat damper 14 opens the upper passage R4 and the lower passage R5, and the differential / vent switching damper 15 Is the differential / foot mode that closes the vent port 23, the heat damper 14 opens the upper passage R4 and the lower passage R5, the differential / vent switching damper 15 closes the defroster port 22, and the heat damper 14 closes the lower passage R5. The differential / vent switching damper 15 can be switched to a blowing mode such as a defroster mode in which the vent port 23 is closed, and the heat damper 14 in a foot mode in which the upper passage R4 is closed.

  Next, control by the air conditioning control device 3 will be described. The air conditioning control device 3 is a microcomputer composed of a known central processing unit, ROM, RAM, and the like. Although not shown, the air conditioning control device 3 is connected to various sensors such as an outside air temperature sensor, a solar radiation sensor, an inside air temperature sensor, and a water temperature sensor, various switches such as a temperature setting switch in the passenger compartment, an air volume change switch, and a refrigeration cycle device Has been. As shown in FIG. 3, the air-conditioning control device 3 includes a first energizing switch that switches between a power supply state and a cut-off state for the upper heating element 31 of the electric heater 12 in addition to the blower motor 10 a and the actuator 4. 5, a second energizing switch 6 that switches between a power supply state and a cut-off state for the intermediate heating element 32, and a third energization switch 7 that switches between a power supply state and a cut-off state for the lower heating element 33 are connected. Has been. And the air-conditioning control apparatus 3 operate | moves according to a predetermined | prescribed program, and controls the ventilation motor 10a, the actuator 4, the 1st-3rd electricity supply switch 5-7, etc.

  The air conditioning control device 3 calculates and sets the target opening of the air mix damper 13 based on the occupant's set temperature, outside air temperature, and the like. When it is determined that heating is necessary, the target opening of the air mix damper 13 is increased so that the amount of rocking upward of the closing plate portion 13b of the air mix damper 13 is large (the opening degree of the hot air passage R2 is large). On the other hand, when it is determined that cooling is necessary, the amount of rocking downward of the closing plate portion 13b of the air mix damper 13 is large (the opening degree of the hot air passage R2 is small). The target opening degree of the air mix damper 13 is set. The air conditioning control device 3 outputs an operation signal to the actuator 4 after the target opening is calculated, and rotates the air mix damper 13.

  In the description of this embodiment, “the large opening” of the air mix damper 13 means that the opening of the hot air passage R2 is large, and “the small” opening of the air mix damper 13 means that the warm air Let us say that the opening degree of the passage R2 is small.

  The target opening of the air mix damper 13 is repeatedly calculated and set in a predetermined extremely short cycle while the air conditioner 1 is in operation. For example, when the occupant raises the set temperature, the setting is reset so that the target opening degree of the air mix damper 13 is increased. Further, when the temperature in the passenger compartment becomes stable as when a certain amount of time has passed since the start of heating, the target opening of the air mix damper 13 is set to be smaller than immediately after the start of heating.

  Moreover, the air-conditioning control apparatus 3 operates the electric heater 12 when it judges that heating is required. At this time, when the temperature in the passenger compartment is far away from the set temperature of the occupant, for example, when the vehicle is left for a long time in an environment where the outside air temperature is low in winter, the air conditioning control device 3 Assuming that the heating capacity is necessary, the first to third energizing switches 5 to 7 are closed to supply power to all of the upper heating element 31, the intermediate heating element 32, and the lower heating element 33.

  On the other hand, when the air conditioner 1 is in an OFF state or in a cooling state, the first to third energizing switches 5 to 7 are opened and the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 are opened. Shut off the power supply. In addition, the air conditioning control device 3 can output control signals to the first to third energizing switches 5 to 7 at different timings individually according to the required heating capacity.

  The air conditioning control device 3 basically supplies power to only one of the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 when the heating capacity may be low (low heating control). ). At this time, when the lowest heating capacity is sufficient, power is supplied only to the lower heating element 33. When a slightly higher capacity is required among the low heating capacity, power is supplied only to the upper heating element 31. When a higher capability is required, power is supplied only to the intermediate heating element 32.

  On the other hand, when a high heating capacity is required, power is supplied to only two of the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 (high heating control). At this time, if a lower heating capacity is sufficient among the high heating capacity, power is supplied to the upper heating element 31 and the lower heating element 33, and if a slightly higher capacity is required, the intermediate heating element 32 and Electric power is supplied to the lower heating element 33, and when higher capacity is required, electric power is supplied to the upper heating element 31 and the intermediate heating element 32.

  Hereinafter, specific control by the air conditioning control device 3 will be specifically described based on the flowcharts shown in FIGS. 4 and 5. The flowchart shown in FIG. 4 shows the control when the heating capacity is lowered during operation with a higher heating capacity that is lower than the maximum heating capacity.

  In step SA1 of the flowchart, it is determined whether or not the blowing fan 10 is blowing air. The determination in step SA1 can be made based on, for example, ON / OFF of an air conditioning switch. If it is determined NO in step SA1 and no air is blown, the process proceeds to step SA2 to cut off the power supply of the upper heating element 31, the intermediate heating element 32, and the lower heating element 33. Thereby, abnormal overheating of the electric heater 12 can be prevented.

  On the other hand, if YES is determined in step SA1, the process proceeds to step SA3 to determine whether or not the opening degree of the air mix damper 13 is large. If it is determined YES in step SA3 and the opening of the air mix damper 13 is large, it means that a high heating capacity is required, and the process proceeds to step SA4, where the upper heating element 31 and the intermediate heating element 32 are processed. The power is supplied to the lower heating element 33 and the power supply to the lower heating element 33 is cut off (high heating control).

  When it is determined NO in step SA3, low heating control is performed. That is, it progresses from step SA3 to step SA5, and it is determined whether the opening degree of the air mix damper 13 is the maximum side within the range of the intermediate opening degree and the intermediate opening degree. If YES is determined in step SA5 and the opening of the air mix damper 13 is medium and large, it means that a stronger heating capacity is required, and the process proceeds to step SA6 to generate intermediate heat. Electric power is supplied to the body 32 and power supply to the upper heating element 31 and the lower heating element 33 is cut off. By supplying electric power only to the intermediate heating element 32, a larger heating capacity can be obtained as compared with the case where electric power is supplied only to the upper heating element 31 and the lower heating element 33.

  When it is determined NO in step SA5, the process proceeds to step SA7, and it is determined whether or not the opening of the air mix damper 13 is an intermediate opening and is on the minimum side within the range of the intermediate opening. If it is determined YES in step SA7 and the opening of the air mix damper 13 is a medium opening and smaller, it means that a heating capacity that is weaker than that determined in step SA5 is required. In step SA8, power is supplied to the upper heating element 31, and power supply to the intermediate heating element 32 and the lower heating element 33 is cut off. By supplying electric power only to the upper heating element 31, the heating capacity is smaller than when supplying electric power only to the intermediate heating element 32, but larger heating than when supplying electric power only to the lower heating element 33. Ability is gained.

  If NO is determined in step SA7, the process proceeds to step SA9, and it is determined whether or not the opening degree of the air mix damper 13 is small. If it is determined as YES in step SA9 and the opening degree of the air mix damper 13 is small, it means that the heating capacity is weaker than that determined in step SA7, and the process proceeds to step SA10 and the lower heating element. Electric power is supplied only to 33, and power supply to the upper heating element 31 and the intermediate heating element 32 is cut off. By supplying electric power only to the lower heating element 33, the heating capacity becomes smaller than when supplying electric power only to the upper heating element 31 and the intermediate heating element 32.

  Therefore, when switching from the high heating control to the low heating control, the heating capacity of the electric heater 12 gradually decreases, so that the temperature change of the blown air can be reduced before and after switching from the high heating control to the low heating control. It becomes possible.

  When the air mix damper 13 is at the maximum opening, power is supplied to all of the upper heating element 31, the intermediate heating element 32, and the lower heating element 33. From this state, the opening of the air mixing damper 13 is small. Then, the heating capacity will be reduced. When reducing the heating capacity from the maximum, first, power is supplied to the upper heating element 31 and the intermediate heating element 32, and the power supply to the lower heating element 33 is shut off. Thereafter, power is supplied to the intermediate heating element 32 and the lower heating element 33, and the power supply to the upper heating element 31 is shut off. Thereafter, power is supplied to the upper heating element 31 and the lower heating element 33, and the power supply of the intermediate heating element 32 is shut off. This makes it possible to reduce the temperature change of the blown air before and after switching from maximum heating to high heating control.

  Moreover, the flowchart shown in FIG. 5 has shown the control in the case of raising a heating capability during a driving | operation with a low heating capability.

  In step SB1 of the flowchart, the same determination as in the flowchart shown in FIG. 4 is performed. If it is determined NO in step SB1 and the air is not blown, the process proceeds to step SB2, and the power supply to the upper heating element 31, the intermediate heating element 32, and the lower heating element 33 is cut off.

  On the other hand, when it determines with YES at step SB1, it progresses to step SB3 and it is determined whether the opening degree of the air mix damper 13 is small. If YES in step SB3 and the opening of the air mix damper 13 is small, it means that a low heating capacity is required, and the process proceeds to step SB4 to supply power to the lower heating element 33. The power supply to the upper heating element 31 and the intermediate heating element 32 is cut off (low heating control).

  If NO is determined in step SB3, the process proceeds to step SB5, and it is determined whether or not the opening of the air mix damper 13 is an intermediate opening and is on the minimum side within the range of the intermediate opening. If it is determined as YES in step SB5 and the opening degree of the air mix damper 13 is a medium opening degree and smaller, it means that a stronger heating capacity is required than in the case where it is determined in step SB3. In step SB6, power is supplied to the upper heating element 31, and power supply to the intermediate heating element 32 and the lower heating element 33 is cut off. By supplying power only to the upper heating element 31, a large heating capacity can be obtained as compared with the case where power is supplied only to the lower heating element 33, but smaller than when supplying power only to the intermediate heating element 32. Heating capacity is obtained.

  When it is determined NO in step SB5, the process proceeds to step SB7, where it is determined whether or not the opening degree of the air mix damper 13 is the medium opening degree and the maximum side within the range of the intermediate opening degree. If it is determined as YES in step SB7 and the opening degree of the air mix damper 13 is medium and large, it means that a stronger heating capacity is required than in the case where determination is made in step SB5. In step SB8, power is supplied to the intermediate heating element 32, and power supply to the upper heating element 31 and the lower heating element 33 is cut off. By supplying electric power only to the intermediate heating element 32, a larger heating capacity can be obtained as compared with the case where electric power is supplied only to the upper heating element 31 and the lower heating element 33.

  When it is determined NO in step SB7, the process proceeds to step SB9, where it is determined whether the opening degree of the air mix damper 13 is large. If it is determined as YES in step SB9 and the opening degree of the air mix damper 13 is large, it means that a stronger heating capacity is required than in the case determined in step SB7, and the process proceeds to step SB10 to perform high heating control. I do. In step SB10, power is supplied to the upper heating element 31 and the intermediate heating element 32, and power supply to the lower heating element 33 is cut off.

  Therefore, before the switching from the low heating control to the high heating control, the heating capacity by the electric heater 12 gradually increases, so that it is possible to reduce the temperature change of the blown air before and after switching from the low heating control to the high heating control. become.

  As described above, according to the vehicle air conditioner 1 according to this embodiment, before switching from the low heating control to the high heating control, the power is first supplied to the lower heating element 33 disposed in the portion where the wind speed is low. After that, the power supply to the lower heating element 33 is stopped and the electric power is supplied to the upper heating element 31 and the intermediate heating element 32 arranged in the part where the wind speed is high. It is possible to prevent the temperature of the blown air from changing greatly to prevent the passenger from feeling uncomfortable and to improve comfort.

  In addition, when switching from the high heating control to the low heating control, after supplying power first to the intermediate heating element 32 disposed in the part where the wind speed is high, the power supply to the intermediate heating element 32 is stopped, Since electric power is supplied to the upper heating element 31 and the lower heating element 33 that are arranged at a part where the wind speed is low, it is possible to prevent the temperature of the blown air from greatly changing before and after switching of the heating capacity. It is possible to prevent the user from feeling uncomfortable and improve comfort.

In the above SL embodiment has described the case of applying the present invention to the full center type air conditioner which houses a blower fan 10 in the same casing 16 as the electric heater 12 is not limited to this, for example, the blower fan It is also possible to apply the present invention to a semi-center type air conditioner that is housed in a separate casing from the electric heater 12 and arranged on one side in the vehicle width direction.

  The above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  As described above, the vehicle air conditioner according to the present invention can be mounted on, for example, an electric vehicle.

DESCRIPTION OF SYMBOLS 1 Vehicle air conditioner 3 Air conditioning control apparatus 10 Blower fan 11 Evaporator 12 Electric heater 13 Air mix damper 16 Casing 31 Upper heating element (2nd heating element)
32 Intermediate heating element (third heating element)
33 Lower heating element (first heating element)
R air flow path

Claims (2)

An electric heater having a first heating element , a second heating element, and a third heating element that generate heat by the supply of electric power, and configured to heat the passing external air;
An evaporator for cooling external air passing therethrough,
A casing having a hot air passage and a cold air passage in which the electric heater and the evaporator are respectively disposed, and an air mix space communicating with the downstream side of the hot air passage and the cold air passage ;
An air mix damper that is accommodated in the casing and changes the amount of hot air and the amount of cold air flowing into the air mix space by opening and closing the hot air passage and the cold air passage; and
An air conditioning control device for controlling the electric heater and the air mix damper ,
The conditioned air introduced into the casings grayed, in vehicle air-conditioning system configured to supply to each part of the passenger compartment from is passed through the electric heater and the evaporator,
The first heating element is disposed at a part where the wind speed is lower than the arrangement part of the second heating element in the warm air passage ,
The third heating element is arranged at a portion where the wind speed is higher than the arrangement portion of the second heating element in the warm air passage,
The air conditioning control device calculates a target opening of the hot air passage of the air mix damper, and when the target opening is a large opening that requires high heating capacity, the second heating element and the above Electric power is supplied to the third heating element and power is not supplied to the first heating element, and the target opening is within the range of the medium opening of the heating capacity that is lower than the large opening to the large opening. When the opening is on the large opening side, power is supplied only to the third heating element, and the target opening is within the range of the medium opening from the large opening side of the medium opening and When the heating capacity is low and the opening is on the small opening side, electric power is supplied only to the second heating element, and the target opening is lower than the intermediate opening from the intermediate opening. if it becomes small opening degree of the vehicular air, characterized in that it is configured for supplying power only to the first heating element Apparatus. An electric heater having a first heating element, a second heating element, and a third heating element that generate heat by the supply of electric power, and configured to heat the passing external air;
An evaporator for cooling external air passing therethrough,
A casing having a hot air passage and a cold air passage in which the electric heater and the evaporator are respectively disposed, and an air mix space communicating with the downstream side of the hot air passage and the cold air passage;
An air mix damper that is accommodated in the casing and changes the amount of hot air and the amount of cold air flowing into the air mix space by opening and closing the hot air passage and the cold air passage; and
An air conditioning control device for controlling the electric heater and the air mix damper,
In the vehicle air conditioner configured to supply the air conditioning air introduced into the casing to each part of the passenger compartment after passing through the electric heater and the evaporator,
The first heating element is disposed at a part where the wind speed is lower than the arrangement part of the second heating element in the warm air passage,
The third heating element is arranged at a portion where the wind speed is higher than the arrangement portion of the second heating element in the warm air passage,
The air conditioning control device calculates a target opening degree of the hot air passage of the air mix damper, and when the target opening degree is a small opening degree that requires a low heating capacity, When only the power is supplied and the target opening is within the range of the medium opening of the heating capacity higher than that at the small opening from the small opening, and the opening is on the small opening side, Electric power is supplied only to the second heating element, and the target opening is an opening from the small opening side of the intermediate opening to the large opening side within the range of the intermediate opening and the heating capacity is high. In this case, power is supplied only to the third heating element, and the second heat generation is performed when the target opening is a large opening having a heating capacity higher than the intermediate opening from the intermediate opening. vehicular air, characterized in that the body and supplies power to the third heating element is configured to the non-supply of power to the first heating element Apparatus.

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