JP5454497B2 - Air conditioner for vehicles - Google Patents

Description

  The present invention relates to a vehicle air conditioner, and adjusts the position of an inside / outside air switching damper of an air conditioner according to the state of a blower of the air conditioner even when the air conditioner is activated while the vehicle is running. Thus, the air conditioner is smoothly activated.

  2. Description of the Related Art Conventionally, in an air conditioner mounted on a vehicle, air that is conditioned and taken into the vehicle interior is air outside the vehicle (outside air) or air in the vehicle interior (inside air) is circulated. There is a switching member (called an inside / outside air switching damper). When the air conditioner detects that the air outside the passenger compartment is dirty while operating in the outside air introduction mode, the inside and outside air of the vehicle air conditioner that controls to switch from the outside air introduction mode to the inside air circulation mode is detected. A control device is described in Patent Document 1.

  In a vehicle equipped with an air conditioner, air outside the passenger compartment may flow into the passenger compartment through the outside air inlet for the air conditioner when the vehicle is traveling. In this case, when the blower (blower) built in the air conditioner is stopped, the blower is rotated in the reverse or forward rotation by the external force due to the incoming air. In general, when a sirocco fan is used for the blower, the blower is reversed by the inflow air, and when a turbofan is used, the blower is normally rotated by the inflow air.

  A blower of a general on-vehicle air conditioner is rotationally driven by a DC motor with a brush or a motor with a sensor that can detect a position using a Hall IC or the like. The motor with brush can be energized according to the position of the rotor of the motor by the brush contact, and the motor with sensor can detect the magnetic pole position of the motor. Is possible. Therefore, in the air conditioner employing these motors, the air conditioner is stopped while the vehicle is running, and the air conditioner blower is rotated by the outside air flowing in from the outside air introduction port. Even when the apparatus is activated, the air conditioner can be activated relatively smoothly without alignment as in the initial lock.

  On the other hand, as a need for a motor for driving a blower of an in-vehicle air conditioner, instead of a DC motor with a brush or a motor with a sensor, it is possible to extend the life and reduce the noise, and to realize cost reduction and space saving. There is a demand for using a sensorless motor.

  When a brushless and sensorless motor is used as the motor for driving the blower, if the air conditioner is started while the blower is rotating during the above-mentioned vehicle running, alignment such as initial locking is performed. It is necessary to forcibly align the magnetic pole position of the motor. That is, even when a brushless and sensorless motor is used as the motor of the blower, the rotation state of the blower can be activated by performing start-up control of the blower such as initial lock when the air conditioner is activated while the vehicle is running. is there.

Japanese Patent No. 3356008 (FIGS. 1 and 2)

  However, when a brushless and sensorless motor is used as the motor for driving the blower, and when the starter control is performed without a sensor such as an initial lock while the blower is rotating, abnormal noise is generated in the vehicle interior. was there. This is because the vibration caused by the rotation of the blower motor during the initial lock is amplified in the passenger compartment, resulting in an abnormal sound source that gives the passenger a sense of incongruity.

  In view of the above problems, the present invention provides an air conditioner that uses a brushless and sensorless motor as a drive motor for a blower, in a state where the blower is rotating forward or reverse by outside air flowing in through an outside air introduction port. Provided is an air conditioner that can start a blower without generating abnormal noise that makes a passenger feel uncomfortable by an inexpensive method without using start-up control such as initial locking for a drive motor. is there.

  In order to solve the above-mentioned problems, the invention of claim 1 is a vehicle air conditioner (1) driven and controlled by an electronic control device (10), wherein the blower unit of the vehicle air conditioner (1) is provided. The blower motor (25) for driving the blower (26) incorporated in (2) is constituted by a sensorless AC motor, and the blower unit (2) is connected to the electronic control unit (10) when the blower (26) is started. ) Has an inside / outside air switching state detection means for detecting the position of the inside / outside air switching member (22), and when the vehicle is running, the position of the inside / outside air switching member (22) is set to the inside air. An inside / outside air switching member moving means that moves to a predetermined position closer to the outside air introduction port (24) than the introduction port (23), and after the movement of the inside / outside air switching member (22) to the predetermined position, the blower motor (25) Launched A vehicle air conditioning system characterized by providing a that motor starting means.

  As a result, when the blower is started, the position of the inside / outside air switching member is moved closer to the outside air introduction port than the inside air introduction port by the electronic control unit, so that the rotation of the blower at the time of startup is lowered and noise is reduced. .

  The invention of claim 2 is characterized in that the predetermined position is a position closer to the outside air introduction port (24) than an intermediate point between the inside air introduction port (23) and the outside air introduction port (24). The vehicle air conditioner according to Item 1.

  As a result, the position of the inside / outside air switching member at the time of start-up of the blower is closer to the outside air introduction port than the intermediate point between the inside air introduction port and the outside air introduction port. Is reduced.

  The invention according to claim 3 is characterized in that the predetermined position is a position where the inside / outside air switching member (22) completely closes the outside air introduction port (24). Device.

  As a result, the position of the inside / outside air switching member at the time of starting the blower becomes a position to completely close the outside air introduction port, so that the rotation of the blower at the time of starting becomes very low or stops, so that the noise is reduced. To do.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, a vehicle speed detecting means (44) for detecting a vehicle speed is connected to the electronic control device (10), and the inside / outside air switching member is connected. The moving means is a vehicle air conditioner characterized in that when the vehicle speed is equal to or higher than a predetermined value, the position of the inside / outside air switching member (22) is moved to the predetermined position.

  As a result, when the blower is started, the position of the inside / outside air switching member is moved closer to the outside air introduction port than the inside air introduction port by the electronic control device only when the vehicle speed is high, so the start time of the blower when the vehicle speed is low is reduced. Can be shortened.

  The invention of claim 5 is the invention according to any one of claims 1 to 3, wherein the blower motor (25) is a three-phase AC motor including a three-phase inverter circuit (18), and the three-phase motor is provided. The inverter circuit (18) is provided with motor current detecting means for detecting a motor current flowing out from at least one of the phases when generating the U-phase, V-phase, and W-phase constituting the three-phase AC motor. Connected to the inside / outside air switching member moving means of the control device (10), the inside / outside air switching member moving means sets the position of the inside / outside air switching member (22) to the predetermined position when the motor current exceeds a predetermined value. The vehicle air conditioner is characterized by being moved to the position.

  Thereby, when the motor current is large at the time of starting the blower, that is, when the rotation of the blower is high, the position of the inside / outside air switching damper is moved closer to the outside air introduction port than the inside air introduction port by the electronic control unit. The start-up time of the blower when the rotation of the blower is small can be shortened.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the motor current detecting means is provided in a signal circuit for one phase of the blower motor (25). A vehicle air conditioner characterized by turning on the lower arm of one phase.

  Thereby, the structure of a motor current detection means can be simplified.

  The invention of claim 7 is the invention according to any one of claims 1 to 3, wherein the blower motor (25) is constituted by a three-phase AC motor provided with a three-phase inverter circuit (18), and the electronic control An internal / external air switching member moving means of the device (10) is connected to a rotational speed detecting means for detecting the rotational speed at the time of power generation of the three-phase AC motor, and the internal / external air switching member moving means has the rotational speed of a predetermined value. In the above case, the vehicle air conditioner is characterized in that the position of the inside / outside air switching member (22) is moved to the predetermined position.

  As a result, when the blower motor is rotating at the time of starting the blower, the position of the inside / outside air switching member is moved closer to the outside air introduction port than the inside air introduction port by the electronic control unit. The start-up time of the blower can be shortened.

  The invention according to claim 8 is the invention according to claim 7, wherein the rotation speed detecting means is one cycle time of a pulse signal obtained from a comparison of induced voltages induced in each phase during power generation of the three-phase AC motor. A vehicle air conditioner that detects the rotational speed by measuring

  Thereby, detection of the rotation speed of a blower motor can be comprised with a simple circuit, and the structure of the vehicle air conditioner can be simplified.

  In addition, the code | symbol attached | subjected above is an example which shows a corresponding relationship with the specific embodiment as described in embodiment mentioned later.

(A) is the whole block diagram which shows the arrangement | positioning of the blower unit, cooling unit, and heater unit in one Embodiment of the air conditioning apparatus for vehicles which concerns on this invention, and the connection with the electronic controller which controls these, (b) is ( It is explanatory drawing explaining operation | movement of the inside / outside air switching apparatus in the blower unit shown to a). FIG. 1A is a flowchart showing a control procedure of the first embodiment of the start-up control of the vehicle air conditioner performed by the electronic control device shown in FIG. 1A, and FIG. It is a flowchart which shows the control procedure of the modification of the 1st Example of the control at the time of starting of the air conditioning apparatus for vehicles which the electronic controller shown in FIG. It is a flowchart which shows the control procedure of the 2nd Example of the starting control of the air conditioning apparatus for vehicles which the electronic control apparatus shown to Fig.1 (a) performs. It is a flowchart which shows the control procedure of the 3rd Example of the starting control of the air conditioning apparatus for vehicles which the electronic control apparatus shown to Fig.1 (a) performs. 4A is a circuit diagram showing an example of a circuit configuration for detecting the motor current of the blower motor in the control procedure shown in FIG. 4, and FIG. 4B is a circuit diagram for detecting the motor current of the blower motor in the control procedure shown in FIG. It is a circuit diagram which shows the other example of a structure. It is a flowchart which shows the control procedure of the 4th Example of the starting control of the air conditioning apparatus for vehicles which the electronic control apparatus shown to Fig.1 (a) performs. (A) is a circuit diagram showing an example of the configuration of a circuit for detecting the rotation speed of the blower motor in the control procedure shown in FIG. 6, and (b) is a waveform diagram showing waveforms on the input side of the comparator shown in (a). (C) is a wave form diagram which shows the waveform of the output side of the comparator shown to (a). (A) is a waveform diagram showing a waveform of a VW voltage comparison with respect to a UV voltage comparison when the blower motor rotates forward due to the inflow of outside air when the vehicle air conditioner is in a stopped state, and (b) is a waveform diagram showing the waveform of the vehicle air conditioner. It is a wave form diagram which shows the waveform of the VW voltage comparison with respect to UV voltage comparison when a blower motor reverse | inverts by the inflow of external air at the time of a stop state.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Moreover, also about each embodiment, the same code | symbol is attached | subjected to the part of the same structure, and the description is abbreviate | omitted or simplified.

  Fig.1 (a) shows the whole structure of one Embodiment of the air conditioning apparatus 1 for vehicles which concerns on this invention. A vehicle air conditioner (hereinafter referred to as an auto air conditioner) 1 includes a blower unit 2, an air conditioner unit 3 including a cooling unit and a heater unit (not shown), and an auto air conditioner ECU 10 which is an electronic control device for driving and controlling these units. . The blower unit 2 has an inside air introduction port 23 and an outside air introduction port 24 in the case 20, and a discharge port 27 for sucked air is connected to the air conditioning unit 3. Also, inside the case 20 of the blower unit 2 are provided an inside / outside air switching damper 22 and a blower 26 which are inside / outside air switching members. The inside / outside air switching damper 22 is driven by a damper motor 21 which is an inside / outside air switching member moving means to block one of the inside air introduction port 23 and the outside air introduction port 24. The blower 26 sends air taken from the inside air introduction port 23 or the outside air introduction port 24 into the air conditioning unit 3 from the discharge port 27, and is rotationally driven by the blower motor 25. A sensorless AC motor is used for the blower motor 25.

  The air conditioning unit 3 adjusts the temperature of the air sent from the blower unit 2 and blows it out into the vehicle interior. Inside the air conditioning unit main body 30, an evaporator that cools the air, a heater core that warms the air, and the cooled air There is an air mix damper that adjusts the warming condition. The air whose temperature is adjusted by the evaporator, the heater core and the air mix damper is discharged into the vehicle interior from any of the front seat outlet (FACE) 31, the foot outlet (FOOT) 32, or the defroster outlet (DEF) 33. Is done. The amount of temperature-controlled air discharged from each air outlet is adjusted by opening and closing the air outlet switching damper. Since the internal configuration of the air conditioning unit main body 30 is well known and is not directly related to the present invention, illustration and further description thereof are omitted.

  The auto air conditioner ECU 10 receives switch signals from a temperature setting switch 4, an inside / outside air changeover switch 5 and an auto switch 6 on a vehicle control panel (not shown), and each temperature sensor (inside air sensor 41, outside air sensor) provided inside and outside the vehicle interior. 42 and the detected value from the water temperature sensor 43), and the blower unit 2 and the air conditioning unit 3 are driven and controlled so that the temperature in the passenger compartment is kept at the set temperature by the temperature setting switch 4. The auto air conditioner ECU 10 may be connected to a solar radiation sensor that detects the amount of solar radiation. In addition, a vehicle speed sensor 44 that is a vehicle speed detection means is also connected to the automatic air conditioner ECU 10 of the present embodiment.

  The auto air conditioner ECU 10 controls the air based on the input signal from each switch so that the vehicle interior temperature becomes a set value by the temperature setting switch 4 and according to the state of the inside / outside air changeover switch 5 and the state of the auto switch 6. The air outlet temperature, air outlet volume and outlet are automatically calculated. Then, control of the rotational position of the damper motor 21, control of the rotational speed of the blower motor 25, and automatic control of each actuator in the air conditioning unit 3 are performed.

  FIG. 1B illustrates the position and operation of the inside / outside air switching damper 22 which is the inside / outside air switching device in the blower unit 2 shown in FIG. The illustration of the damper motor 21 is omitted. The inside / outside air switching damper 22 is switched to the position of point A and point B by the damper motor 21 shown in FIG. When the inside / outside air switching damper 22 is at the position of the point A indicated by the solid line, the inside air introduction port 23 of the blower unit 2 is closed, and when the inside / outside air switching damper 22 is at the position of the point B indicated by the broken line, 2 outside air inlet 24 is closed. In the present invention, the inside / outside air switching damper 22 can be stopped before the position of the point B indicated by the broken line by the control of the automatic air conditioner ECU 10 described later. The point before the position of the point B is, for example, an intermediate point C between the point A and the point B and a position D between the point C and the point B. The position D can be an intermediate point between the point C and the point B. It is assumed that the damper motor 21 has a built-in damper position detecting means or the automatic air conditioner ECU 10 has a damper position detecting means.

  In the present invention, when the air conditioner 1 is stopped while the vehicle is running and the position of the inside / outside air switching damper 22 is at point A by the inside / outside air changeover switch 5 (outside air introduction state), the auto air conditioner 1 is activated. In this case, the startup control of the damper motor 21 by the automatic air conditioner ECU 10 will be described. Several embodiments will be described below.

  FIG. 2A is a flowchart showing a control procedure of the first embodiment of the startup control of the auto air conditioner 1 performed by the auto air conditioner ECU 10 shown in FIG. Implemented at startup. In step 201, it is first determined whether or not the auto air conditioner 1 is in the inside air mode. Whether or not the auto air conditioner 1 is in the inside air mode can be known by detecting the position of the inside / outside air changeover switch 5, the damper position detection signal from the damper motor 21, or the damper position detected by the auto air conditioner ECU 10 itself. If the auto air conditioner 1 is in the inside air mode (YES), the process proceeds to step 203, the blower motor 25 is rotated to start the auto air conditioner 1, and this routine is terminated. Step 201 corresponds to the inside / outside air switching state detection means of the auto air conditioner ECU 10, and step 205 corresponds to the motor starting means of the auto air conditioner ECU 10.

  On the other hand, if the determination in step 201 is not the inside air mode (NO), the process proceeds to step 202. In step 202, the inside / outside air switching damper 22 is moved to the side where the outside air introduction port 24 is closed. That is, the inside / outside air switching damper 22 is moved to the position of the point B indicated by the broken line, and the outside air inlet 24 of the blower unit 2 is completely closed. After moving the inside / outside air switching damper 22 to the point B, the routine proceeds to step 203, where the auto air conditioner ECU 10 which is the blower starting means rotates the blower motor 25 to start the auto air conditioner 1 and ends this routine.

  FIG. 2B is a flowchart showing a control procedure of a modification of the first embodiment of the start-up control of the auto air conditioner 1 performed by the auto air conditioner ECU 10 shown in FIG. Sometimes implemented. Therefore, the same steps as those in the first embodiment will be described with the same step numbers. In step 201, it is determined whether or not the auto air conditioner 1 is in the inside air mode. If the auto air conditioner 1 is in the inside air mode (YES), the process proceeds to step 203, the blower motor 25 is rotated to start the auto air conditioner 1 and this routine is finished. To do. This procedure is the same as in the first embodiment.

  On the other hand, if the determination in step 201 is not the inside air mode (NO), the process proceeds to step 202 '. In step 202, the inside / outside air switching damper 22 is moved to the side where the outside air introduction port 24 is closed. In step 202 ', the inside / outside air switching damper 22 is moved to a predetermined position close to the position where the outside air introduction port 24 is closed. Let This predetermined position is, for example, the point D shown in FIG. 1B, that is, the point B indicated by a broken line where the inside / outside air switching damper 22 closes the outside air introduction port 24, and an intermediate point C between the points A and B. Is an intermediate point D. When the inside / outside air switching damper 22 is at the position of point D, the inside air almost flows into the blower 26, and a slight amount of outside air is taken into the blower 26 as inflow air, so that the blower 26 is not affected by the outside air. Step 203 after step 202 'is the same as that in the first embodiment. The blower motor 25 is rotated to start the automatic air conditioner 1, and this routine is terminated.

  Thus, when the automatic air conditioner 1 is activated, the inside / outside air switching damper 22 is on the side that closes the inside air introduction port 23, and when the outside air is flowing in, this is detected and the inside / outside air switching damper 22 is connected to the outside air introduction port 24. When the automatic air conditioner 1 is started, rotation of the blower motor 25 due to inflow of outside air is reduced. As a result, in the first embodiment or its modification, it is possible to prevent or reduce the abnormal noise that may have occurred when the auto air conditioner 1 is started. The degree of this reduction is around 15 dB against abnormal noise generated when the present invention is not carried out.

  FIG. 3 is a flowchart showing the control procedure of the second embodiment of the start-up control of the auto air conditioner 1 performed by the auto air conditioner ECU 10 shown in FIG. In step 301, it is first determined whether or not the auto air conditioner 1 is in the inside air mode. If the auto air conditioner 1 is in the inside air mode (YES), the process proceeds to step 305, the blower motor 25 is rotated to start the auto air conditioner 1, and this routine is terminated.

  On the other hand, if the determination in step 301 is not the inside air mode (NO), the process proceeds to step 302. In step 302, the vehicle speed is detected by the vehicle speed sensor 44 shown in FIG. In step 303, it is determined whether or not the vehicle speed is equal to or higher than a predetermined value. If the vehicle speed is lower than the predetermined value (NO), the process proceeds to step 305, the blower motor 25 is rotated and the automatic air conditioner 1 is started. finish. The predetermined value varies depending on the type of vehicle on which the auto air conditioner 1 is mounted, but is a value of about 60 km / h.

  If the determination in step 303 is YES, the process proceeds to step 304, and the inside / outside air switching damper 22 is moved to the side where the outside air introduction port 24 is closed as in the first embodiment, or the first embodiment. As in the modified example, the inside / outside air switching damper 22 is moved to a predetermined position close to the position where the outside air introduction port 24 is closed. In this state, the process proceeds to step 305, the blower motor 25 is rotated to activate the automatic air conditioner 1, and this routine is terminated.

  Here, the reason why the auto air conditioner 1 is started in the outside air mode even when the vehicle speed is low and the inside / outside air switching mode is set to the outside air mode when the auto air conditioner 1 is activated will be described. The blower 26 in the blower unit 2 of the auto air conditioner 1 is rotated by the outside air flowing from the outside air introduction port 24 as long as the vehicle speed does not exceed a predetermined value even when the inside / outside air switching mode is the outside air mode. First, it starts to rotate around the vehicle speed exceeding 60 km / h. Moreover, if the speed is up to about 80 km / h, the rotation speed of the blower 26 due to the outside air flowing in from the outside air introduction port 24 is low, and when the vehicle speed approaches 100 km / h, the rotation speed of the blower 26 due to the outside air taken in from the outside air introduction port 24 is low. It increases, and it becomes about 300rpm although it changes with car models. When the activation of the auto air conditioner 1 is started in this state, an abnormal noise can be heard in the passenger compartment when the rotation direction of the blower 26 at the time of activation is different from the rotation direction of the blower 26 at the time of operation.

  The vehicle speed at which the blower 26 of the auto air conditioner 1 in which the inside / outside air switching mode is in the outside air mode starts to rotate due to the outside air flowing in from the outside air introduction port 24 varies depending on the vehicle type when the vehicle in which the auto air conditioner 1 is not operating. However, when the vehicle speed is low, even if the auto air conditioner 1 is started in a state where the blower 26 is rotating due to the outside air flowing in from the outside air introduction port 24, no abnormal noise is heard in the vehicle interior or it is not audible. Since the sound does not give a pleasant feeling, the control according to the vehicle speed is performed when the auto air conditioner 1 is activated as in the second embodiment.

  Thus, when the automatic air conditioner 1 is activated, the inside / outside air switching damper 22 is on the side that closes the inside air introduction port 23, and when the vehicle speed is high, the inside / outside air switching damper 22 is closed or closed. When the automatic air conditioner 1 is activated, abnormal noise can be prevented or reduced when the automatic air conditioner 1 is activated. The degree of this reduction is the same as in the first embodiment.

  FIG. 4 is a flowchart showing the control procedure of the third embodiment of the startup control of the auto air conditioner 1 performed by the auto air conditioner ECU 10 shown in FIG. In the third embodiment, description will be made assuming that the blower motor 25 is a three-phase AC motor. In step 401, it is first determined whether or not the auto air conditioner 1 is in the inside air mode. When the auto air conditioner 1 is in the inside air mode (YES), the routine proceeds to step 406, the blower motor 25 is rotated to start the auto air conditioner 1, and this routine is ended. On the other hand, if the determination in step 401 is not the inside air mode (NO), the process proceeds to step 402. In step 402, the lower arm of any phase of the three-phase AC blower motor 25 is turned on to pass a current through the lower arm. The configuration and arm of the three-phase AC blower motor 25 will be described later.

  When the air conditioner 1 is started up and the blower 26 is rotated by the air flowing from the outside air inlet 24, the three-phase AC blower motor 25 is rotated by the blower 26, and the three-phase AC blower motor 25 generates power. Generate motor current. Therefore, in the subsequent step 403, the motor current of the three-phase AC blower motor 25 is detected, and in the next step 404, it is determined whether or not the motor current is greater than or equal to a predetermined value. When the motor current is less than the predetermined value (NO), the routine proceeds to step 406, the three-phase AC blower motor 25 is rotated to start the automatic air conditioner 1, and this routine is terminated. This predetermined value is the value of the motor current generated when the blower 26 is approximately 300 rpm.

  If the determination in step 404 is YES, the process proceeds to step 405, and the inside / outside air switching damper 22 is moved to the side where the outside air introduction port 24 is closed as in the first embodiment, or the first embodiment. As in the modified example, the inside / outside air switching damper 22 is moved to a predetermined position close to the position where the outside air introduction port 24 is closed. In this state, the process proceeds to step 406, the three-phase AC blower motor 25 is rotated to start the automatic air conditioner 1, and this routine is terminated.

  Here, the control for turning on the lower arm of any phase of the three-phase AC blower motor 26 in step 402 and causing the current to flow through the lower arm will be described with reference to FIGS. 5 (a) and 5 (b). As shown in FIG. 5A, the three-phase AC blower motor 25 is a brushless motor, and includes a U-phase winding 25U, a V-phase winding 25V, and a W-phase winding 25W, and a three-phase inverter circuit that is a drive circuit. The rotation is controlled by a signal flowing through a signal circuit connecting 18 and each phase winding. The three-phase inverter circuit 18 includes two switching elements 11U and 11L for the U-phase winding 25U, two switching elements 12V and 12VL for the V-phase winding 25V, and two switching elements for the W-phase winding 25W. There are 13U and 13L. The two switching elements for each phase are connected in series between the high battery voltage HV and the low battery voltage LV, and are called the upper arm and the lower arm, respectively. That is, the switching element 11U is called an upper arm, and the switching element 11L is called a lower arm.

  The auto air conditioner ECU 10 receives signals UU and UL for driving the switching elements 11U and 11L, signals VU and VL for driving the switching elements 12U and 12L, and signals WU and WL for driving the switching elements 13U and 13L. Is output. In this embodiment, a current detection sensor 14U is provided as a motor current detection means between the switching element 11L and the lower battery voltage LV. When the auto air conditioner 1 is activated, the auto air conditioner ECU 10 outputs a signal for driving the switching element 11L (U-phase lower arm), and the U-phase lower arm is turned on. When the U-phase lower arm is turned on, the U-phase of the three-phase AC blower motor 25 is rotated in the state where the blower is rotated (reversed) by the external air flow introduced into the vehicle interior from the outside air introduction port while the vehicle is running in the outside air introduction state. The electric current from 25U flows through the current detection sensor 14, and the automatic air conditioner ECU 10 can detect this current value. A shunt resistor can also be used for the current detection sensor 14U.

  The auto air conditioner ECU 10 stores the outflow current value of each phase at the time of power generation generated by the three-phase AC blower motor 25 with respect to the rotation speed when the blower rotates by outside air flowing in. The auto air conditioner ECU 10 detects the detected current The rotation speed of the blower at the time of detection can be known from the value. If the rotational speed of the blower is high when the auto air conditioner 1 is activated, the external airflow is moved by moving the inside / outside air switching damper 22 to a position where the outside air introduction port 24 is closed or a predetermined position close to the closing position as described above. And the auto air conditioner 1 is started in a state where the rotational speed of the blower is reduced.

  In the embodiment of FIG. 5A, the current detection sensor 14U is provided only between the switching element 11L and the lower battery voltage LV, but the current detection sensor 14 may be provided in another phase. That is, as indicated by a broken line, current detection sensors 14V and 14W are provided between the switching element 12L and the low battery voltage LV, or between the switching element 13L and the low potential battery voltage VL, respectively, and the motor currents of other phases are supplied. You may make it detect.

  FIG. 5B shows an embodiment in which a current detection sensor 15U is provided instead of the current detection sensor 14U described in FIG. In the embodiment shown in FIG. 5B, the current detection sensor 15U is provided in a circuit between the connection point of the upper and lower arms of the U phase and the U phase winding 25U. When the auto air conditioner 1 is started, if the lower arm of the U phase is turned on by a signal UL from the auto air conditioner ECU 10, the blower is rotated by the external air current introduced from the outside air introduction port into the vehicle interior while the vehicle is running in the outside air introduction state ( In this state, the current from the U-phase 25U of the three-phase AC blower motor 25 flows through the current detection sensor 15U, and this current value is detected by the auto air conditioner ECU 10, and the inside / outside air switching damper 22 is outside the air as described above. The inlet 24 is moved to a position to close or a predetermined position close to the position to close.

  In the embodiment of FIG. 5B, the current detection sensor 15U is provided in a circuit between the connection point of the upper and lower arms of the U phase and the U phase winding 25U. It may be provided in this phase. That is, as indicated by a broken line, a current detection sensor 15V is provided in a circuit between a connection point between the upper and lower arms of the V phase and the V phase winding 25V, and a connection point between the upper and lower arms of the W phase A current detection sensor 15W may be provided in a circuit between the W-phase winding 25W and another phase motor current may be detected.

  In the second embodiment, it is necessary to adjust the predetermined value of the vehicle speed for whether or not the control for preventing or reducing the inflow of outside air is performed for each vehicle type. According to the third embodiment, the motor current is used to adjust the outside air flow. Since it is possible to determine a predetermined value indicating whether or not to perform control for preventing or reducing inflow, it is possible to determine the predetermined value not depending on the vehicle type but depending on the structure of the motor. For this reason, if it is a vehicle using the same motor, the adjustment for every vehicle type becomes unnecessary.

  FIG. 6 is a flowchart showing the control procedure of the fourth embodiment of the startup control of the auto air conditioner 1 performed by the auto air conditioner ECU 10 shown in FIG. In the fourth embodiment, description will be made assuming that the blower motor 25 is a three-phase AC motor. In step 601, it is first determined whether or not the auto air conditioner 1 is in the inside air mode. If the auto air conditioner 1 is in the inside air mode (YES), the process proceeds to step 605, the blower motor 25 is rotated to start the auto air conditioner 1, and this routine is terminated.

  On the other hand, if the determination in step 601 is not the inside air mode (NO), the process proceeds to step 602. In step 602, the rotational speed of the blower motor 25 due to the above-described external airflow when the automatic air conditioner 1 is stopped is detected. The rotational speed of the blower motor 25 due to the external airflow can be calculated by detecting the induced voltage generated in the blower motor 25. However, the method of detecting the rotational speed of the blower motor 25 due to the external airflow from the induced voltage generated in the blower motor 25. Will be described later. In step 603, it is determined whether or not the rotational speed of the blower motor 25 is equal to or greater than a predetermined value. If the rotational speed of the blower motor 25 is less than the predetermined value (NO), the process proceeds to step 605 to rotate the blower motor 25 to 1 is started and this routine is terminated.

  If the determination in step 603 is YES, the process proceeds to step 604, and the inside / outside air switching damper 22 is moved to the side for closing the outside air introduction port 24 as in the first embodiment, or the first embodiment. As in the modified example, the inside / outside air switching damper 22 is moved to a predetermined position close to the position where the outside air introduction port 24 is closed. In this state, the process proceeds to step 605, the blower motor 25 is rotated to activate the automatic air conditioner 1, and this routine is terminated.

  Here, the blower motor rotation speed detecting means for detecting the rotation speed of the three-phase AC blower motor 26 from the induced voltage induced in each phase of the three-phase AC blower motor 26 in step 602 will be described with reference to FIGS. To do. The configurations of the three-phase AC blower motor 25 and the three-phase inverter circuit 18 have been described with reference to FIG.

  In the fourth embodiment, as shown in FIG. 7A, a rotation speed detection circuit 50 connected to the three-phase inverter circuit 18 is provided. The rotation speed detection circuit 50 includes two comparators 51 and 52 and an arithmetic processing unit 53, and an output of the arithmetic processing unit 53 is input to the automatic air conditioner ECU 10. The comparator 51 compares the voltage Vu at the coupling point between the U-phase switching elements 11U and 11L with the voltage Vv at the coupling point between the V-phase switching elements 12U and 12L. The comparator 52 compares the voltage Vv at the coupling point between the V-phase switching elements 12U and 12L with the voltage Vw at the coupling point between the W-phase switching elements 13U and 13L. Then, the comparison output Vuv of the comparator 51 and the comparison output Vvw of the comparison air 52 are input to the arithmetic processing unit 53.

  FIG. 7B shows the signal waveforms on the input side of the comparators 51 and 52 shown in FIG. 7A, that is, the three-phase when the three-phase AC blower motor 25 is rotated by the inflow of outside air. The induced voltage waveform input into the three-phase inverter circuit 18 from each phase of the AC blower motor 25 is shown. The waveform indicated by the solid line is the U-phase induced voltage waveform Vu, the waveform indicated by the broken line is the V-phase induced voltage waveform Vv, and the waveform indicated by the chain line is the W-phase induced voltage waveform Vw.

  FIG. 7C is a pulse signal waveform showing the waveform on the output side of the comparators 51 and 52 shown in FIG. In the UV phase comparison voltage Vuv, in the waveform diagram shown in FIG. 7B, the portion where the voltage Vu is higher than the voltage Vv is at the high level, and the VW phase comparison voltage Vvw is shown in FIG. 7B. In the waveform diagram, the portion where the voltage Vv is higher than the voltage Vw is at the high level. The arithmetic processing unit 53 can calculate the rotation speed of the three-phase AC blower motor 25 by measuring one cycle time Tcyc of the VW-phase comparison voltage Vvw. For example, if the three-phase AC blower motor 25 is a two-pole pair, it can be calculated as rotational speed = (1 / (2 × Tcyc)).

  In the fourth embodiment, the rotational direction of the three-phase AC blower motor 25 due to the inflow of outside air may be normal or reverse with respect to the rotational direction of the three-phase AC blower motor 25 when the auto air conditioner is operating normally. Judgment is possible. FIG. 8A shows the pulse signal waveform of the VW-phase comparison voltage Vvw relative to the pulse signal waveform of the UV-phase comparison voltage Vuv when the outside air flows when the auto air conditioner is stopped and the three-phase AC blower motor 25 rotates forward. Is shown. When the rotation direction due to the inflow of outside air into the three-phase AC blower motor 25 rotates in the forward direction, the pulse waveform of the VW-phase comparison voltage Vvw is delayed with respect to the pulse waveform of the UV-phase comparison voltage Vuv. On the other hand, FIG. 8B shows a pulse signal of the VW phase comparison voltage Vvw with respect to the pulse signal waveform of the UV phase comparison voltage Vuv when the outside air flows in and the three-phase AC blower motor 25 is reversed when the auto air conditioner is stopped. A waveform is shown. When the rotation direction due to the inflow of outside air from the three-phase AC blower motor 25 is reversed, the pulse waveform of the UV phase comparison voltage Vuv is delayed with respect to the pulse waveform of the VW phase comparison voltage Vvw.

  In this way, if the rotation direction of the three-phase AC blower motor 25 due to the inflow of outside air is determined to be normal or reverse, it is determined whether or not the inside air mode or control for closing the outside air inlet with the inside / outside air switching damper to a predetermined position is possible. The predetermined value of the rotation speed can be set to another value.

  In the fourth embodiment, since the number of rotations of the three-phase AC blower motor 25 is detected using an induced voltage that is induced when the three-phase AC blower motor 25 rotates due to the inflow of outside air, it is affected by the characteristics of the motor. Less. Although there is an influence of the number of pole pairs for judging the rotation speed in relation to the characteristics of the three-phase AC blower motor 25, the fourth implementation is performed even if, for example, other windings or the strength of the magnetic force is changed. In the example, adjustment for each motor is unnecessary or can be reduced.

1 Auto air conditioner (vehicle air conditioner)
2 Blower unit 3 Air conditioning unit (cooling unit / heater unit)
10 Auto air conditioner ECU (control device)
11U, 11L, 12U, 12L, 13U, 13L Switching element (arm)
14, 15 Current detection sensor 21 Damper motor 22 Inside / outside air switching damper (switching member)
23 Inside air introduction port 24 Outside air introduction port 25 Blower motor 30 Air conditioning unit body 50 Rotation speed detection circuit 51, 52 Comparator 53 Arithmetic processing unit

Claims (8)

A vehicle air conditioner (1) driven and controlled by an electronic control unit (10),
The blower motor (25) for driving the blower (26) built in the blower unit (2) of the vehicle air conditioner (1) is constituted by a sensorless AC motor,
In the electronic control device (10),
When the blower (26) is activated, it has inside / outside air switching state detection means for detecting the position of the inside / outside air switching member (22) built in the blower unit (2), and the vehicle is running An inside / outside air switching member moving means for moving the position of the inside / outside air switching member (22) to a predetermined position closer to the outside air introduction port (24) than the inside air introduction port (23);
An air conditioner for a vehicle, comprising: motor starting means for starting the blower motor (25) after the inside / outside air switching member (22) is moved to the predetermined position.   2. The predetermined position is a position closer to the outside air introduction port (24) than an intermediate point (C) between the inside air introduction port (23) and the outside air introduction port (24). Air conditioner for vehicles.   The vehicle air conditioner according to claim 2, wherein the predetermined position is a position (B) where the inside / outside air switching member (22) completely closes the outside air introduction port (24). Vehicle speed detecting means (44) for detecting the vehicle speed is connected to the electronic control unit (10);
The inside / outside air switching member moving means moves the position of the inside / outside air switching member (22) to the predetermined position when the vehicle speed is equal to or higher than a predetermined value. The vehicle air conditioner according to any one of the preceding claims. The blower motor (25) is composed of a three-phase AC motor having a three-phase inverter circuit (18),
The three-phase inverter circuit (18) is provided with motor current detecting means for detecting a motor current flowing out from at least one of the U-phase, V-phase, and W-phase power generating the three-phase AC motor. To the inside / outside air switching member moving means of the electronic control device (10),
The inside / outside air switching member moving means moves the position of the inside / outside air switching member (22) to the predetermined position when the motor current is equal to or greater than a predetermined value. The vehicle air conditioner according to any one of the above.   6. The motor current detecting means is provided in a signal circuit for one phase of the blower motor (25), and turns on the lower arm of the one phase when the motor current is detected. The air conditioning apparatus for vehicles described in 2. The blower motor (25) is composed of a three-phase AC motor having a three-phase inverter circuit (18),
A rotation speed detecting means for detecting a rotation speed during power generation of the three-phase AC motor is connected to the inside / outside air switching member moving means of the electronic control device (10),
The inside / outside air switching member moving means moves the position of the inside / outside air switching member (22) to the predetermined position when the rotational speed is a predetermined value or more. The vehicle air conditioner according to any one of the above.   The rotational speed detection means detects the rotational speed by measuring one cycle time of a pulse signal obtained from comparison of induced voltages induced in each phase during power generation of the three-phase AC motor. The vehicle air conditioner according to claim 7.

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