JP3287110B2 - Electric vehicle air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for an electric vehicle in which a compressor of a refrigerant circuit mounted on an electric vehicle controls the number of revolutions of a compressor motor in accordance with an output set for air conditioning control.

[0002]

2. Description of the Related Art In recent years, electric vehicles using a traction motor driven by a vehicle-mounted battery as a drive source have been put into practical use instead of vehicles using an internal combustion engine. And
In an electric vehicle, an air conditioner is being mounted similarly to a gasoline internal combustion engine vehicle.

In this case, the air conditioner controls air conditioning such as cooling and heating and dehumidification by a refrigerant circulating in the refrigeration cycle, and the refrigerant is compressed by a compressor constituting the refrigeration cycle. In an electric vehicle, the compressor is rotationally driven by a compressor motor that is electrically driven to rotate by a vehicle-mounted battery.

[0004]

By the way, in an electric vehicle, the traveling motor is driven to rotate at a rotational speed generally corresponding to the traveling speed of the vehicle. Therefore, the noise generated tends to increase as the traveling speed increases. is there. Therefore, when the compressor motor is driven to rotate during traveling, the noise generated by the compressor motor is not so noticeable to the occupants in the passenger compartment.

[0005] However, when the electric vehicle is stopped, the noise generated by the traveling motor is reduced, and the vehicle should be quiet even in the vehicle interior. If so, the compressor motor may be driven to rotate at a high speed depending on the set output state of the air-conditioning control, which may cause extremely unpleasant noise for the occupant.

In this case, for example, if the user wants to preferentially control the air conditioning in the passenger compartment regardless of the running speed of the electric vehicle, noise is generated from the air conditioner when the vehicle is stopped or running at a low speed. However, if it is desired to suppress the noise caused by air conditioning control by giving priority to the silent state in the vehicle cabin, it is necessary to take measures such as stopping the air conditioner depending on the environmental condition. In addition, there is a problem that the air conditioning control is completely stopped.

In an electric vehicle, when air conditioning operation is performed during driving, the air conditioning operation must be performed at night in order to save the discharge amount of the battery and secure the electric power required for driving. Preliminary air-conditioning operation, in which the air-conditioning operation is preliminarily performed so that the vehicle interior is air-conditioned to a predetermined temperature when power is supplied from an external power source while the battery is being charged. There is. However,
Performing air-conditioning operation at night in this way is a problem when the surrounding environment is quiet, since noise generated by the operation of the compressor becomes a problem. Is difficult to use.

The present invention has been made in view of the above circumstances, and has as its object to perform air-conditioning operation when the vehicle is stopped or at a low speed, or to perform pre-air-conditioning operation during a charging period such as at night. In such a case, it is an object of the present invention to provide an air conditioner for an electric vehicle that can minimize the generation of noise due to the operation of a compressor so as not to cause discomfort to the user and the local residents.

[0009]

SUMMARY OF THE INVENTION The present invention is to be mounted on an electric vehicle, and is provided in an indoor room provided in a refrigerant circuit.
It is intended for an air conditioner for an electric vehicle that performs an air conditioning operation by performing heat exchange between a refrigerant flowing through a heat exchanger and vehicle interior air passing through the indoor heat exchanger,
A rotation control means for controlling a rotation speed of a motor of a compressor provided in the refrigerant circuit according to a setting output of air conditioning control, a vehicle speed sensor for detecting a vehicle speed, and limiting a rotation speed of the compressor motor to a certain rotation speed or less. Rotation speed limiting means, and when the vehicle speed detected by the vehicle speed sensor is equal to or less than a predetermined speed, driving the rotation control means through the rotation speed limitation means to reduce the rotation speed of the compressor motor to a certain rotation speed or less. And a silent control means for performing a silent control operation for restricting the noise control operation.

Further, in the above configuration, even when the vehicle speed detected by the vehicle speed sensor is equal to or lower than a predetermined speed, the silent control means may increase the rotation speed of the compressor motor required for air conditioning control at that time to a predetermined upper limit value. In the above case, it is preferable that the silent control operation is disabled and the compressor motor is driven and controlled at a required rotation speed.

Further, in each of the above structures, a silent switch may be provided in a driver's seat portion of the electric vehicle, and the control means may execute the silent control operation only when the silent switch is operated. .

Further, the present invention provides an indoor heat exchanger mounted in an electric vehicle and provided in a refrigerant circuit.
It is intended for an air conditioner for an electric vehicle that performs an air conditioning operation by performing heat exchange between a circulating refrigerant and vehicle interior air passing through the indoor heat exchanger. A rotation control means for controlling a rotation speed of a compressor motor and a cooling blower of an outdoor heat exchanger provided in the refrigerant circuit, a vehicle speed sensor for detecting a vehicle speed, and a rotation speed of the compressor motor and the cooling blower. Rotation speed limiting means for limiting the rotation speed to a certain rotation speed or less,
When the vehicle speed detected by the vehicle speed sensor is equal to or lower than a predetermined speed, the rotation speed of the compressor motor and the cooling blower is limited to a predetermined speed or less by driving the rotation control means via the rotation speed limiting means. And a silent control means for performing a silent control operation.

[0013] In the above configuration, even when the vehicle speed detected by the vehicle speed sensor is equal to or lower than a predetermined speed, the silent control means may increase the rotation speed of the compressor motor required for air conditioning control at that time to a predetermined upper limit value. In the above case, it is preferable that the silent control operation is invalidated and the compressor motor and the cooling blower are driven and controlled at a required rotation speed.

Further, in each of the above configurations, a silent switch may be provided in a driver's seat portion of the electric vehicle, and the control means may be configured to execute the silent control operation only when the silent switch is operated. .

Further, the present invention relates to an indoor heat exchanger mounted in an electric vehicle and provided in a refrigerant circuit.
The air-conditioning system for electric vehicles is designed to perform an air-conditioning operation by exchanging heat between a circulating refrigerant and vehicle interior air passing through the indoor heat exchanger. Rotation control means for controlling the number of rotations of a compressor motor provided in a circuit, a vehicle speed sensor for detecting a vehicle speed, pressure detection means for detecting a discharge pressure of the compressor, and the compressor motor according to a set output of air conditioning control Calculating means for calculating the noise level estimated from the required rotation speed of the compressor and the discharge pressure of the compressor by the pressure detection means; rotation speed limiting means for controlling so as to reduce the rotation speed of the compressor motor; When the vehicle speed detected by the vehicle speed sensor is equal to or lower than a predetermined speed, the compressor motor is driven via the rotation speed limiting unit. Having characterized in that the estimated generated noise level which is configured by providing a static sound control means for causing the silent control operation of controlling the rotational speed to be equal to or less than the noise reference level by the.

A silent switch may be provided in a driver's seat of the electric vehicle, and the control means may be configured to execute the silent control operation only when the silent switch is operated.

Further, for an air conditioner for an electric vehicle having a pre-air-conditioning operation mode in which the vehicle interior is preliminarily air-conditioned when a battery which is a driving power source of the vehicle is charged, the arithmetic means is provided with the pre-processing unit. When the air-conditioning operation is being performed, the calculation may be performed based on the pre-air-conditioning operation noise reference level set lower than the noise reference level.

[0018]

According to the first aspect of the present invention, when the vehicle speed detection output from the vehicle speed sensor exceeds a predetermined value, the silent control unit controls the rotation of the compressor motor by the rotation control unit. When the vehicle speed detection output from the vehicle speed sensor is equal to or less than a predetermined value, the compressor motor is rotationally controlled by the rotation control means via the rotation speed limiting means. By doing so, for example, even when the rotation speed of the compressor motor according to the set output of the air conditioning control is equal to or higher than a certain rotation speed, the air conditioning operation by the silent control operation that limits the rotation speed to not exceed the certain rotation speed is performed. Will be implemented.

With this arrangement, the air-conditioning operation can be performed while suppressing the noise generated by the compressor motor for air-conditioning control in response to the case where the vehicle speed is lower than the predetermined speed and the noise generated by the traveling motor is small. For a passenger in the cabin, it is possible to maintain a quiet state while keeping the reduction of the air conditioning capacity by the air conditioning control within an allowable range.

According to the second aspect of the present invention, even if the vehicle speed detection output from the vehicle speed sensor is equal to or less than the predetermined value, the rotational speed of the compressor motor based on the set output of the air conditioning control in that state is equal to the predetermined upper limit. If the value is equal to or greater than the value, the silent control unit gives priority to the air conditioning control over the silent operation control, invalidates the silent control operation of limiting the number of rotations of the compressor motor by the rotation number limiting unit, and performs normal air conditioning control. When the air-conditioning environment in the vehicle compartment requires quick air-conditioning control, the air-conditioning control is quickly performed by giving priority to the air-conditioning control so that the occupant does not feel uncomfortable.

According to the third aspect of the present invention, the above-described silent control operation can be executed by operating the silent switch from the driver's seat by the user, so that the user is required to perform the operation. Accordingly, it is possible to select between giving priority to the air conditioning control and giving priority to the silent control.

According to the air conditioner for an electric vehicle of the fourth aspect, in addition to the operation of the first aspect, in the air conditioner having a cooling blower in the outdoor heat exchanger, the compressor motor and the cooling blower are also provided. A similar silent control operation can be performed, and a comfortable vehicle environment can be realized by performing silent control in the vehicle interior.

According to the fifth aspect of the present invention, even if the vehicle speed detection output from the vehicle speed sensor is equal to or less than a predetermined value, the rotation of the compressor motor or the cooling blower according to the output of the air conditioning control in that state. When the number is equal to or greater than the predetermined upper limit, the silent control means gives priority to the air conditioning control over the silent operation control, and invalidates the silent control operation for limiting the number of revolutions of the compressor motor by the number of revolutions limiting means. If the air-conditioning environment in the vehicle compartment requires quick air-conditioning control, priority is given to this, and the air-conditioning control is quickly performed so that the occupant does not feel uncomfortable. be able to.

According to the air conditioner for an electric vehicle according to the sixth aspect, the above-described silent control operation can be executed by operating the silent switch from the driver's seat by the user. Accordingly, it is possible to select between giving priority to the air conditioning control and giving priority to the silent control.

According to the seventh aspect of the present invention, when the vehicle speed detection output from the vehicle speed sensor exceeds a predetermined value, the silent control means controls the rotation of the compressor motor by the rotation control means. Then, the air-conditioning operation according to the set output of the air-conditioning control is performed, and when the vehicle speed detection output from the vehicle speed sensor is equal to or less than a predetermined value, the rotation speed of the compressor is controlled as follows. That is,
The calculating means calculates a noise level estimated from the required number of revolutions of the compressor motor according to the set output of the air-conditioning control and the discharge pressure of the compressor by the pressure detecting means. If the reference level is exceeded, the number of revolutions of the compressor motor is limited by the rotation control means via the number of revolutions limiting means, and the number of revolutions is controlled so that the noise level generated from the compressor motor is equal to or less than the noise reference level. The silent control operation is performed.

With this arrangement, the air-conditioning operation can be performed while suppressing the noise generated by the compressor motor for air-conditioning control in response to the case where the vehicle speed is lower than the predetermined speed and the noise generated by the traveling motor is small. For a passenger in the cabin, it is possible to maintain a quiet state while keeping the reduction of the air conditioning capacity by the air conditioning control within an allowable range.

According to the air conditioner for an electric vehicle according to the present invention, the above-mentioned silent control operation can be executed by operating the silent switch from the driver's seat by the user, so that the user is required Accordingly, it is possible to select between giving priority to the air conditioning control and giving priority to the silent control.

According to the air conditioner for an electric vehicle of the ninth aspect, a pre-air-conditioning operation mode in which battery consumption is reduced by performing preliminary air-conditioning operation using a power source when charging the battery at night or the like. Is performed by the calculation means, the calculation is performed based on the pre-air-conditioning operation noise reference level set lower than the noise reference level set during operation, such as at night different from when traveling. Even when the air-conditioning operation is performed in a particularly quiet environment, it is possible to minimize the adverse effects of noise generation on the surroundings.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to an air conditioner for controlling air conditioning such as cooling and heating of a vehicle compartment and dehumidification will be described below with reference to FIGS. FIG. 2 shows a configuration of an indoor unit of an air conditioner, and an inside / outside air switching device 2 provided at an inlet of an air conditioning duct 1 includes:
Inside air inlet 4 or outside air inlet 5 by switching damper 3
It is set so that air can be taken in from either of the above.

The blower 6 is arranged on the upstream side of the air-conditioning duct 1, and is configured to draw air from the inside / outside air switching device 2 side by the rotation of the blower motor 7 and blow the air to the downstream side of the air-conditioning duct 1. The air conditioning duct 1 includes a first unit 8 and a second unit 9, in which a first indoor heat exchanger 10 is disposed, and a second indoor unit 9 includes a second indoor heat exchanger 10. A heat exchanger 11 and two auxiliary heaters (PTC heaters) 12, 12 are arranged.

On the discharge side of the second unit 9, a differential air outlet 13 for blowing out toward the inner side of the vehicle window, a heater outlet 14 for blowing out to the feet of the occupant, and a blowout for the occupant's chest. Vent outlet 15 is provided. In this case, the vent outlet 15 is further branched at its tip into a center outlet 16 and side outlets 17 and 18. In addition, each of the outlets 13, 14, 16, 17, 18
Outlet switching dampers 19, 2 for opening and closing them.
0, 21, 22, and 23 are provided.

Next, in FIG. 3 showing a refrigerant circuit, a compressor 24 for sucking, compressing and discharging the refrigerant is provided in a closed container 2.
5 is provided with a compressor motor 26 (see FIG. 1). A four-way switching valve 28 is provided on the discharge passage 27 side of the compressor 24, and is switched so that the discharged refrigerant flows to the indoor heat exchangers 10 and 11 or the outdoor heat exchanger 29 side. ing. The first indoor heat exchanger 10 and the outdoor heat exchanger 29 are connected by a refrigerant pipe 30. In the middle of the refrigerant pipe 30, a cooling capillary tube 31 and a heating capillary tube 32 are respectively checked. It is arranged in a state of being connected in parallel with the valves 33 and 34.

The indoor second heat exchanger 11 disposed in the second unit 9 is mainly used for dehumidification, and is provided between the indoor second heat exchanger 11 and the indoor first heat exchanger 10. Is connected to a capillary tube 35 for dehumidification. The dehumidifying capillary tube 35 is provided with a parallel bypass circuit 36, and the parallel bypass circuit 36 is provided with a reversible solenoid valve 37. Reversible solenoid valve 37
Means that the refrigerant flow is always allowed from the indoor first heat exchanger 10 to the indoor second heat exchanger 11 side, and the refrigerant flow in the opposite direction is allowed when the solenoid valve coil is energized, and is blocked when not energized. It is supposed to be.

One end of the refrigerant circuit 38 provided as a dehumidifying bypass circuit is connected between the first indoor heat exchanger 10 and the cooling capillary tube 31. The other end of the refrigerant circuit 38 is connected to the four-way switching valve 28 and the accumulator 40 via a normally closed solenoid valve 39. The solenoid valve 39 allows the flow of the refrigerant in an energized state.

The accumulator 40 separates the introduced refrigerant into gas and liquid, stores the liquid refrigerant, and supplies only the gas refrigerant to the compressor 24. Its capacity is, for example, 50 to 100% of the total refrigerant charge. What can be accommodated is used. In addition, the accumulator 40 in the present embodiment is actually composed of a first accumulator 41 directly mounted inside the compressor 24 and a second accumulator 42 provided separately from the compressor 24. The compressor unit 43 is configured by the compressor 24, the accumulator 40, the four-way switching valve 28, and the like.

Next, referring to FIG. 4, which is attached to a vehicle compartment of an electric vehicle, an outdoor heat exchanger 29 having cooling blowers 44, 45 is connected to a compressor unit 43, and operates during a cooling operation. It is arranged so that outdoor air can be sufficiently taken in and cooled during both the heating operation and the heating operation. Further, an inverter 46 and a control unit 47 as rotation control means for controlling the rotation speed of the compressor motor 26 of the compressor 24 are housed in an electric box 48. The dashboard 49 in front of the driver's seat is provided with a control panel 50 for the user to operate.

FIG. 5 showing the entire control panel 50.
In the upper part, an air outlet mode changeover switch group 51 for switching the air outlet is provided, and in the lower part thereof, an air volume changeover switch 52, a silent switch 53, and an inside / outside air changeover switch 54 are provided. An operation mode changeover switch group 55 for switching the operation mode is provided below, and a temperature adjustment lever 56 for adjusting the set temperature is provided at the bottom.

The outlet mode changeover switch group 51 is used to switch the direction of the conditioned air blown into the vehicle compartment by controlling the opening and closing of the outlet changeover dampers 19, 20, 21, 22, 23. A vent mode switch 51a for setting blowout to the chest, a bi-level mode switch 51b for setting blowout to both the occupant's head and chest, and feet, a heater mode switch 51c for setting blowout to the occupant's feet, The air conditioner includes a heater differential mode switch 51d for setting blow-off to both the inner surface of the front window glass and a differential mode switch 51e for setting blow-out to the inner surface of the front window glass.

The operation mode changeover switch 55 includes a stop switch 55a, a blower switch 55b, a cooling switch 55c, and a heating switch 55 for switching among operation stop, air blowing operation, cooling operation, heating operation and dehumidifying operation.
d and a dehumidification switch 55e.

When the vehicle is stopped or running at a low speed, the silent switch 53 is provided to suppress the generation of noise due to the operation of the air conditioner and to set a quiet vehicle interior space. More specifically, the power supply state is controlled so that the rotation speed of the compressor 24 becomes equal to or less than a predetermined rotation speed when the traveling speed becomes equal to or less than a predetermined value. In addition, each of the above-mentioned various switches 51 to 55 is provided with an indicator for displaying the operation state.

Next, in FIG. 1 showing the electrical configuration, the control unit 47 includes a well-known CPU, RAM, and RO.
An air conditioning control program is stored and set in advance, and air conditioning control described later is executed in accordance with an operation instruction from the control panel 50. The control unit 47 has a function as a rotation speed limiting unit and a silent control unit according to the present invention.

The control unit 47 includes various switch groups 51, 52, 53, 5 of the control panel 50.
4, 55 and a signal corresponding to the setting state of the temperature control lever 56 is input. The control unit 47 includes a discharge temperature detector 57, an indoor heat exchanger temperature detector 58, an outdoor heat exchanger temperature detector 59, an outdoor temperature detector 60, a pressure sensor 61, a compressor temperature detector 62, and a vehicle speed sensor. 63 are connected to supply various detection signals.

In this case, the discharge temperature detector 57 detects the temperature of the refrigerant discharged from the compressor 24. The indoor heat exchanger temperature detector 58 detects a surface temperature of the indoor heat exchanger 10 as a temperature related to the indoor heat exchanger 10. The outdoor heat exchanger temperature detector 59 detects the refrigerant temperature as the temperature relating to the outdoor heat exchanger 29. The outdoor temperature detector 60 detects the temperature outside the vehicle. The pressure sensor 61 detects the pressure of the refrigerant discharged from the compressor 24. The compressor temperature detector 62 detects the temperature of the body of the compressor 24. The vehicle speed sensor 63 detects the traveling speed of the vehicle.

A vehicle-mounted battery 64 serving as a power source is configured to supply power to the compressor motor 26 of the compressor 24 via an inverter 46 to be driven, and the supplied current is detected by a current detector 65 and detected by a control unit 47. It gives a signal.

The control unit 47 is connected with inverters 46, blowers 6, blowers 44 and 45, four-way switching valves 28, and solenoid valves 37 and 39 as loads to be controlled by the control unit 47. The control signal is generated by the air-conditioning control program based on the detection signal, and the driving is controlled by the control signal.

Next, the operation of this embodiment will be described with reference to FIG. First, the cooling operation will be described.
That is, when the control panel 50 is operated by the user, the cooling switch 5 of the operation mode changeover switch 55 is operated.
This is the operation when 5c is turned on.

A program for air conditioning control is stored in the control unit 47 in advance, and a program (not shown) for cooling operation control is started by turning on the cooling switch 55c. The control unit 47 sets the flow path of the four-way switching valve 28 so that the refrigerant discharged from the compressor 24 flows into the outdoor heat exchanger 29 during the cooling operation. in this case,
The reversible solenoid valve 37 is set in a closed state.

The control unit 47 sets the number of revolutions of the compressor 24 in accordance with the set position of the temperature control lever 56 of the control panel 50 and controls the drive. For example, when the adjustment position of the temperature adjustment lever 56 is set to the low temperature side, the rotation speed of the compressor 24 is controlled to be high, and when it is set to the high temperature side, the rotation speed of the compressor 24 is controlled. The number is controlled to be low.

During the cooling operation, the high-temperature and high-pressure refrigerant discharged from the compressor 24 is supplied to the outdoor heat exchanger 2.
9, the liquid is liquefied at a high temperature, and then adiabatically expanded when passing through the cooling capillary tube 31 via the check valve 34 to be in a low-temperature and low-pressure atomized state, and the first heat exchange in the room. It flows into the vessel 10.

Thus, in the indoor first heat exchanger 10, the air introduced by the blower 6 into the duct 1 is blown, and the refrigerant exchanges heat with the air to take away the vaporization heat of the air. Cool the air while evaporating. Thereafter, the refrigerant flows into the accumulator 42 via the reversible solenoid valve 27, the indoor second heat exchanger 11, and the four-way switching valve 28. In the accumulator 42, the gas refrigerant and the liquid refrigerant are separated, and only the gas refrigerant is sucked into the compressor 24 and compressed. Thus, in the cooling operation mode, the vehicle interior is cooled by the cooling capacity according to the setting of the temperature control lever 56.

Next, the heating operation will be described. That is, when the control panel 50 is operated by the user, the heating switch 55 d of the operation mode changeover switch 55 is operated.
This is the operation when is turned on.

In this case, the control unit 47
When a program (not shown) for heating operation control is started by turning on the heating switch 55d, the flow path of the four-way switching valve 28 is switched to the refrigerant discharged from the compressor 24 to the indoor second heat exchanger 11 side. The flow is set to flow in, and the reversible solenoid valve 37 is set to the open state.

The control unit 47 sets the number of revolutions of the compressor 24 in accordance with the set position of the temperature control lever 56 of the control panel 50 and controls the drive. For example, when the adjustment position of the temperature adjustment lever 56 is set to a low temperature side, the rotation speed of the compressor 24 is controlled to be a low rotation speed, and when the adjustment position is set to a high temperature side, the rotation speed of the compressor 24 is controlled. The number is controlled to be high.

During the heating operation, the high-temperature and high-pressure refrigerant discharged from the compressor 24 is supplied to the reversible solenoid valve 3.
7, the indoor second heat exchanger 1
1 and the indoor first heat exchanger 10. That is, the air sucked into the duct 1 is supplied to the indoor first heat exchanger 10 and the indoor second heat exchanger 1.
When passing through 1, the refrigerant is heated by the high-temperature and high-pressure refrigerant, while the refrigerant radiates heat and condenses.

Thereafter, the refrigerant condensed by the first indoor heat exchanger 10 and the second indoor heat exchanger 11 is supplied to the check valve 33.
Through the heating capillary tube 32, and then adiabatically expands into a low-temperature and low-pressure mist to flow into the outdoor heat exchanger 29. In the outdoor heat exchanger 29, the low-temperature refrigerant exchanges heat with the outdoor air and evaporates, thereby becoming a gas refrigerant and becoming a four-way switching valve 28.
Through the accumulator 42. In the accumulator 42, the gas refrigerant and the liquid refrigerant are separated, and only the gas refrigerant is sucked into the compressor 24 and compressed. Thus, in the heating operation mode, the vehicle interior is heated by the heating power according to the setting of the temperature control lever 56.

Next, the dehumidifying operation will be described. That is, the control panel 50 is operated by the user, and the dehumidifying switch 55e of the operation mode changeover switch 55 is operated.
This is the operation when is turned on.

In this case, the control unit 47
Starts a program (not shown) for dehumidification operation control by turning on the dehumidification switch 55e,
The flow path of the four-way switching valve 28 is set so that the refrigerant discharged from the compressor 24 flows into the indoor second heat exchanger 11 and the reversible electromagnetic valve 37 is closed so that the dehumidifying capillary tube 35 flows. Set to be a route. Also, during this dehumidifying operation, the solenoid valve 39
Is opened to bypass the refrigerant.

As a result, the refrigerant discharged from the compressor 24 flows into the indoor second heat exchanger 11 via the four-way switching valve 28, and exchanges heat with the air flowing through the duct 1 to be condensed. It starts to heat the air. Subsequently, the condensed refrigerant is supplied to the dehumidifying capillary tube 35.
Adiabatic expansion during the flow of the gas into a low-temperature, low-pressure atomized state, flows into the first indoor heat exchanger 10, and evaporates here to exchange heat with the air passing through the duct 1, thereby cooling it. I will be.

As a result, the air that has flowed into the duct 1 is first cooled in the first indoor heat exchanger 10 to be low-temperature air having a low water vapor pressure, and then passes through the second indoor heat exchanger 11. When heated, the air is blown into the vehicle interior as low-humidity air.

Thereafter, the evaporated refrigerant flows into the accumulator 42 via the solenoid valve 39, bypassing the dehumidifying refrigerant circuit 38. This accumulator 42
In the above, the gas refrigerant and the liquid refrigerant are separated, and only the gas refrigerant is sucked into the compressor 24 and compressed.

The above-mentioned cooling, heating and dehumidifying operations are controlled independently of the running speed of the vehicle. For example, when the running speed of the vehicle is extremely low or when the vehicle is in a stopped state, it is not used. There is a case where the user wants to suppress the noise generated by the air-conditioning control rather than the air-conditioning control state in the vehicle compartment, in particular, the noise generated from the compressor motor 26 by the operation of the compressor 24.

Therefore, in such a case, when the silent switch 53 provided on the control panel 50 is turned on in order to perform the air conditioning control by giving priority to the quietness over the air conditioning temperature control in the vehicle compartment. The operation will be described with reference to the flowchart of the air conditioning control program including the silent control shown in FIG.

That is, the control unit 47
When the air-conditioning control program is started, first, the values of counters, flags, and the like used in the subsequent calculation process are initialized (step S1), followed by detection signals of various sensors and various switches of the control panel 50,
The setting state of the temperature control lever 56 is read (step S2).

Next, the control unit 47 calculates a required rotational speed Nc of the compressor 24 in the operation mode based on the detection signal values of the various sensors read in the previous step S2 and the setting states of the various switches in a predetermined arithmetic expression. (Step S3). Subsequently, when the control unit 47 proceeds to step S4, it determines whether or not the silent switch 53 is turned on. Here, since it is assumed that the silent switch 53 is turned on, “YES” is set. And step S
Go to 5.

In step S5, the control unit 47 determines that the value of the required rotation speed Nc of the compressor 24 calculated in step S3 based on the setting of the silent mode is equal to or more than a predetermined rotation speed, for example, 4000 rpm. It is determined whether or not this is the case, and if "YES" is determined, the process proceeds to step S6. Next, in step S6, the control unit 47 determines whether or not the detected value of the current vehicle speed detected by the vehicle speed sensor 63 is equal to or less than a certain speed, for example, 5 km / h or less.
When it is determined as "S", the process proceeds to step S7.

Thus, the control unit 47
Is a state where the current running state of the vehicle is stopped or running at a low speed, and the number of rotations of the compressor 24 required by the air conditioning control is higher than a predetermined number of rotations. Also, it was determined that the noise generated by the rotation of the compressor 24 was higher.

Then, in step S7, the control unit 47 sets the rotation speed of the compressor 24 to a constant value, for example, 4000 rpm irrespective of the result calculated in step S2. A drive signal is supplied to an inverter 46 for controlling the number of rotations, and a control signal is supplied to each section to execute air conditioning control of a silent control operation.

Thus, when the vehicle is stopped or running at a low speed and the speed of the running motor of the vehicle is low and the generation of noise is small, the generation of noise by the air conditioning control is suppressed to a certain level or less. As a result, it is possible for the user to travel comfortably while performing the air-conditioning control while keeping the vehicle interior quiet.

In the above case, in each of steps S4 to S6, the control unit 47
If it is determined to be "O", it is determined that the condition described above is not satisfied, and the process jumps to step S7 and proceeds to step S2.
The normal air-conditioning control is executed in accordance with the result calculated in step S7. When step S7 ends, the process returns to step S2 to repeatedly execute the same air-conditioning control operation as described above. is there.

In the case described above, when the determination in step S6 is "YES" and the process proceeds to step S7, the control unit 47 causes the blowers 44 and 4 to operate.
Similarly, the number of rotations of 5 can also be controlled to be a constant value, whereby a further silent effect can be expected.

According to the present embodiment, when the silent switch 53 is set to the ON state, the vehicle speed detected by the vehicle speed sensor 63 by the control unit 47 is 5 km / h or less, and various sensors are used. When the required rotation speed Nc of the compressor motor 26 calculated from the detection signal of the type and the setting output of the air conditioning control according to the setting by the control panel 50 is 4000 rpm or more, 4000 r as the instruction value to the inverter 46.
pm, so that the air-conditioning operation is not stopped in a low-speed running state or a stopped state where noise is not generated by the running motor of the vehicle. However, the generation of noise can be suppressed as much as possible, and a comfortable cabin environment for the occupant can be formed.

The silent control operation in the air conditioning control is as follows.
Since the operation is performed with the silent switch 53 provided in the driver's seat portion being on, the occupant can select whether to prioritize the silent control or the air conditioning control, thereby improving the usability.

FIG. 7 shows a second embodiment of the present invention. The difference from the first embodiment is that, as shown in FIG. 7, in the air-conditioning control program, between steps S3 and S4. This is a program in which step S9 is additionally inserted. That is, in the present embodiment, after the air conditioning control program is started, step S3 is executed.
After going through step S9, the control unit 47 determines whether or not the amount of heat required for air conditioning control as a result of the calculations in steps S2 and S3 is equal to or greater than 3000W.

This is because the value of the required rotation speed Nc of the compressor motor 26 calculated from the detection signals of the various sensors and the setting output of the air conditioning control in accordance with the setting by the control panel 50 is converted into the heat quantity required by the air conditioning control. To determine whether it is 3000 W or more.
The necessity of the heat amount of 0 W or more indicates that the air conditioning environment in the passenger compartment is far from the desired state, and that when the silent control operation is performed in this state, the occupant feels uncomfortable. is there.

If the determination of step S9 is "NO", the control unit 47 proceeds to step S4 and thereafter to execute the silent control operation according to the conditions, as in the first embodiment. On the other hand, "YE
S ”, it is necessary to give priority to the air conditioning control. Therefore, the inverter 4 is controlled so that the required rotation speed Nc of the compressor motor 26 calculated in step S3 becomes equal to Nc.
6 is given a control signal to perform an air-conditioning operation.

According to the second embodiment, the control unit 47 converts the number of revolutions Nc of the compressor motor 26 necessary for air-conditioning control to 300
When the vehicle speed is 0 W or more, the air conditioning control is prioritized even when the vehicle speed is 5 km / h or less.
In situations where the occupant is uncomfortable with the air-conditioning condition in the passenger compartment exceeding the allowable range, the air-conditioning control can be given priority over the silent control operation so that a comfortable air-conditioned space can be quickly formed. Become.

FIGS. 8 and 9 show a third embodiment of the present invention. Hereinafter, portions different from the first embodiment will be described. That is, in the present embodiment, the generated noise level S actually generated by the operation of the compressor 24 is
(DB) is estimated, and the compressor motor 26 at that time is estimated.
When the noise level S generated corresponding to the required rotation speed Nc is smaller than the predetermined reference noise level S1, the compressor motor 26 is driven and controlled at the required rotation speed Nc, and the estimated generated noise level S becomes the noise reference level. If it exceeds S1, the number of revolutions Nc of the compressor motor 26 is reduced to control the noise level S to be equal to or lower than the noise reference level S1.

In this case, the noise level S (dB) actually generated by the compressor 24 was measured by the inventors in accordance with various aspects, and as shown in FIG. It has been found that the number increases in proportion to each of the number Nc and the refrigerant discharge pressure Pc of the compressor 24. Therefore, when the value of the generated noise level S is expressed as a function of the rotation speed Nc and the refrigerant discharge pressure Pc, the following expression (1) is obtained. Generated noise level S (dB) = a · Nc + b · Pc + k (1) where a, b, and c are constants.

Therefore, based on this equation (1), the number of revolutions for preventing the noise level S generated by the compressor 26 from exceeding the noise reference level S1, ie, the upper limit NUc of the number of revolutions, is calculated by the following equation (2). Can be sought. The upper limit value of the rotational speed NUc = (S1−b · Pc) / a (2) The control unit 47 performs the silent control according to the flowchart of the program shown in FIG. 8 based on the above principle.

That is, the control unit 47
When the air-conditioning control program is started, first, the values of counters, flags, and the like used in the subsequent calculation process are initialized (step T1).
The detection signals of various sensors including the detection signals of various types, various switches of the control panel 50, and the temperature control lever 56
(Step T2).

Next, the control unit 47 calculates the required rotation speed Nc of the compressor 24 in the operation mode based on the detection signal values of the various sensors read in the previous step T2 and the setting states of the various switches in a predetermined arithmetic expression. (Step T3). Subsequently, when proceeding to Step T4, the control unit 47 determines whether or not the pre-air-conditioning operation is currently being performed.

In this case, the pre-air-conditioning operation is to preliminarily perform the air-conditioning operation by using the charging power source when charging the vehicle-mounted battery 64.
The charging of 4 is often performed when the vehicle is not operated for a long period of time, such as at night, and by performing air conditioning operation to some extent during this period, the vehicle interior can be immediately comfortably used in the morning or the like. Air condition can be controlled,
Further, it is intended to minimize the consumption of the vehicle-mounted battery 64 due to the execution of the air-conditioning operation and to secure a power supply required for traveling.

If the control unit 47 determines "NO" in step T4, the control unit 47 proceeds to step T5 to determine whether or not the silent switch 53 is turned on. In this case, the silent switch 53 is turned on. Is determined, "YES" is determined, and step T is performed.
Proceed to 6. The control unit 47 executes step T6.
Then, it is determined whether or not the detected value of the current vehicle speed detected by the vehicle speed sensor 63 is equal to or lower than a predetermined speed, for example, equal to or lower than 5 km / h. If "YES" is determined, the process proceeds to step T7. Become.

If the control unit 47 determines "YES" in step T4, that is, if the pre-air-conditioning operation is being performed, the control unit 47 jumps to step T7 in order to perform unconditional silent control. Has become. When it is determined "NO" in steps T5 and T6, the normal air-conditioning control is performed (jump to step T11) without performing the silent control.

The control unit 47 executes step T
7, the noise reference level S1 is set to, for example, 50 dB. Then, in step T8, the upper limit value NUc of the number of revolutions of the compressor motor 26 corresponding to the noise reference level S1 is calculated by the above equation (2). Therefore, calculation is performed. At this time, the refrigerant discharge pressure Pc of the compressor 24 is equal to the pressure sensor 6 detected in step T2 described above.
1 detection data is used.

Then, when the control unit 47 proceeds to step T9, the control unit 47 determines the upper limit value NU of the number of revolutions of the compressor motor 26 obtained in correspondence with the noise reference level S1.
c is compared with the required rotation speed Nc of the compressor motor 26 calculated in step T3, and the required rotation speed Nc
Is greater than or equal to the upper limit value NUc, the determination is "YES" and the routine proceeds to step T10, where the required rotational speed Nc is set to the upper limit value Nc.
After substituting Uc, the process proceeds to step T11, and if the required rotation speed Nc is smaller than the upper limit value NUc, “NO”
And jumps to step T11.

Then, in step T11, the control unit 47 supplies a control signal corresponding to the set required number of revolutions Nc of the compressor motor 26 to the inverter 46, and also provides a control signal to each section to control the air conditioning of the silent control operation. Control will be executed.

In this case, in the silent control operation, for example, the rotation speed control of the compressor motor 26 is changed from the current rotation speed to the upper limit value NU set as the required rotation speed Nc.
Control can be performed such that the transition of the rotation speed reduction control to c is gradually reduced (for example, the speed is reduced in units of 100 rotations). Also, the refrigerant discharge pressure P of the compressor 24
When the rotation speed of the compressor motor 26 is increased when the upper limit value NUc of the rotation speed of the compressor motor 26 corresponding to the noise reference level S1 is changed due to a change in c or the like, the rotation speed is similarly gradually increased. It can be controlled to increase. This makes it possible to suppress a sudden change in the rotation speed of the compressor motor 26 and perform stable rotation speed control.

With the above control, in a situation where the speed of the running motor of the vehicle is low and no noise is generated when the vehicle is stopped or running at a low speed, or when the pre-air-conditioning operation mode is executed, the air conditioning is performed. The noise generated by the control is suppressed to a certain level or less, so that the user can comfortably run while performing the air conditioning control while keeping the passenger compartment quiet. In the execution state of the air-conditioning operation mode,
This makes it possible to suppress the generation of noise with respect to the surrounding environment so that the noise is not adversely affected.

Further, in the above case, when it is determined “YES” in step T6 and the process proceeds to step T7, the control unit 47 causes the blowers 44 and 4 to operate.
Similarly, the number of rotations of 5 can also be controlled to be a constant value, whereby a further silent effect can be expected.

According to this embodiment, when the pre-air-conditioning operation mode is being executed or the silent switch 53 is set to the ON state, the control unit 47 detects the vehicle speed by the vehicle speed sensor 63. The required speed Nc of the compressor motor 26 and the refrigerant discharge pressure of the compressor 24 calculated from the detection signals of the various sensors and the setting output of the air conditioning control according to the settings made by the control panel 50 when the vehicle speed is 5 km / h or less. When the generated noise level S estimated from Pc is higher than the noise reference level S1, the upper limit value NUc of the rotation speed of the compressor motor 26 calculated from the noise reference level S1 is set as an instruction value to the inverter 46. To perform a silent control operation to control the drive
In the pre-air-conditioning operation mode execution state, the low-speed running state or the stop state, etc., when the noise generated by the traveling motor of the vehicle is small, the noise generation can be suppressed as much as possible without stopping the air-conditioning operation. Become
The generation of noise in the surrounding environment can be suppressed, and a comfortable cabin environment for the occupant can be formed.

Further, the silent control operation in the air conditioning control is described as follows.
Since the operation is performed with the silent switch 53 provided in the driver's seat portion being on, the occupant can select whether to prioritize the silent control or the air conditioning control, thereby improving the usability.

FIG. 10 shows a fourth embodiment of the present invention. What is different from the third embodiment is that in the silent control operation, when the pre-air-conditioning operation mode is executed,
The pre-air-conditioning operation noise reference level S2, which is a lower value than the above-described noise reference level S1, is set.

FIG. 10 shows the air-conditioning control program. If the control unit 47 determines "YES" in step T4, it proceeds to step T4.
The process then proceeds to step 12, where, for example, 40 dB is set as the noise reference level S2 for the pre-air-conditioning operation, and thereafter the process proceeds to step T8.

Thus, in addition to the effect of the third embodiment, when the pre-air-conditioning operation mode is executed, the value of the noise reference level S2 used for the above-described silent control is set as the value of the noise reference level S2. Since the level is set to a level lower than the value of S1, the pre-air conditioning is performed while minimizing the generation of noise that adversely affects the surroundings when performing the pre-air conditioning operation in a quiet environment such as at night. Driving can be performed.

The present invention is not limited to the above embodiment, but can be modified or expanded as follows. The silent switch can be provided as needed, and the silent control operation can be automatically executed. The values of the noise reference levels S1 and S2 can be set to appropriate values as needed.

[0097]

As described above, according to the air conditioner for an electric vehicle of the present invention, the following effects can be obtained. That is, according to the air conditioner for an electric vehicle, when the vehicle speed detection output from the vehicle speed sensor is equal to or less than a predetermined value, the compressor is controlled by the rotation control unit via the rotation speed limiting unit. By controlling the rotation of the motor, even if the rotation speed of the compressor motor according to the setting output of the air conditioning control is higher than a certain rotation speed, a silent control operation that limits the rotation speed to not exceed the certain rotation speed is performed. Since the vehicle speed is equal to or less than the predetermined speed and the noise generated by the traveling motor is small, the air conditioning operation can be performed while suppressing the noise generated by the compressor motor of the air conditioning control. When the occupants in the passenger compartment can maintain a quiet state while keeping the reduction of the air conditioning capacity by the air conditioning control within the allowable range Cormorant an excellent effect.

According to the second aspect of the present invention, even if the vehicle speed detection output from the vehicle speed sensor is equal to or less than the predetermined value, the rotational speed of the compressor motor based on the set output of the air conditioning control in that state is equal to the predetermined upper limit. If the value is equal to or more than the value, the air conditioning control is prioritized over the silent operation control by the silent control means, and the silent control operation of limiting the number of rotations of the compressor motor by the rotation number limiting means is invalidated to perform normal air conditioning control. Since the air-conditioning environment in the vehicle compartment requires quick air-conditioning control, the air-conditioning control is performed quickly by giving priority to the air-conditioning control so that the occupant does not feel uncomfortable. It has an excellent effect.

According to the third aspect of the present invention, the silent switch is provided in the driver's seat, and the silent control operation is selectively performed by the user operating the silent switch from the driver's seat. Because of this, there is an excellent effect that the user can select whether to prioritize the air conditioning control or the silent control as needed.

According to the air conditioner for an electric vehicle of the fourth aspect, in addition to the operation of the first aspect, in the air conditioner having a cooling blower in the outdoor heat exchanger, the compressor motor and the cooling blower are also used. Since the same silent control operation can be performed, there is an excellent effect that it is possible to perform a silent control of the vehicle interior to realize a comfortable vehicle interior environment.

According to the fifth aspect of the present invention, even if the vehicle speed detection output from the vehicle speed sensor is equal to or less than the predetermined value, the rotation of the compressor motor or the cooling blower based on the set output of the air conditioning control in that state. When the number is equal to or more than the predetermined upper limit, the silent control means gives priority to the air conditioning control over the silent operation control, and the noise control operation for limiting the number of revolutions of the compressor motor by the number of revolutions limiting means is usually disabled. If the air conditioning environment in the vehicle compartment requires quick air-conditioning control, priority is given to this, so that the air-conditioning control is performed quickly so that passengers do not feel uncomfortable. The effect is excellent.

According to the air conditioner for an electric vehicle of the present invention, the silent switch is provided in the driver's seat, and the silent control operation is selectively executed by the user operating the silent switch from the driver's seat. Because of this, there is an excellent effect that the user can select whether to prioritize the air conditioning control or the silent control as needed.

According to the electric vehicle air conditioner of the present invention, when the vehicle speed detection output from the vehicle speed sensor is equal to or less than a predetermined value, the compressor means controls the compressor motor according to the set output of the air conditioning control. The generated noise level estimated from the required rotation speed and the refrigerant discharge pressure of the compressor by the pressure detection means is calculated, and when the calculated generated noise level exceeds the noise reference level, the silent speed control means controls the rotation speed limiting means. Since the rotation speed of the compressor motor is limited by the rotation control means via the, the noise control level is controlled so that the noise level generated from the compressor motor is equal to or lower than the noise reference level. When the vehicle speed is lower than the predetermined speed and the noise generated by the traveling motor is small, the compressor motor for air conditioning control is used. The air conditioning operation can be performed while suppressing the occurrence of that noise, an excellent effect of being able to hold a silent state while within the allowable range the lowering of the air conditioning capacity by the air conditioner control for the passenger in the vehicle compartment.

According to the air conditioner for an electric vehicle of the eighth aspect, since the silent switch is provided so that the above-mentioned silent control operation can be executed from the driver's seat by the user, the use of the silent switch is reduced. This provides an excellent effect that the user can select whether to prioritize the air conditioning control or the silent control as necessary.

According to the ninth aspect of the present invention, in the pre-air-conditioning operation mode, the battery is reduced by performing preliminary air-conditioning operation using a power source at the time of charging the battery at night or the like. Is performed by the calculation means, the calculation is performed based on the pre-air-conditioning operation noise reference level set lower than the noise reference level set during operation. Even when the air-conditioning operation is performed in a particularly quiet environment, it is possible to prevent the adverse effects of noise from being generated on the surroundings as much as possible.

[Brief description of the drawings]

FIG. 1 is an electrical configuration diagram of a main part showing a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a flow path of conditioned air.

FIG. 3 is a schematic circuit diagram showing a flow path of a refrigerant.

FIG. 4 is an explanatory view showing an arrangement state on a vehicle.

FIG. 5 is a front view of a control panel.

FIG. 6 is a flowchart of an air conditioning control program for silent control.

FIG. 7 is a view corresponding to FIG. 6, showing a second embodiment of the present invention.

FIG. 8 is a view corresponding to FIG. 6, showing a third embodiment of the present invention.

FIG. 9 is a correlation diagram of a noise level with respect to a rotation speed of a compressor motor.

FIG. 10 is a view corresponding to FIG. 6, showing a fourth embodiment of the present invention;

[Explanation of symbols]

1 is an air conditioning duct, 2 is an inside / outside air switching device, 3 is a switching damper, 6 is a blower, 7 is a blower motor, 10 is a first indoor heat exchanger, 11 is a second indoor heat exchanger, 13 is a differential air outlet,
14 is a heater outlet, 15 is a vent outlet, 24 is a compressor, 26 is a compressor motor, 27 is a discharge passage, 28 is a four-way switching valve, 29 is an outdoor heat exchanger, 30 is a refrigerant pipe, and 31 is a cooling capillary tube. , 32 is a heating capillary tube, 33 and 34 are check valves, 35 is a dehumidification capillary tube, 36 is a parallel bypass circuit,
7 is a reversible solenoid valve, 38 is a refrigerant circuit, 39 is a solenoid valve, 40
Is an accumulator, 43 is a compressor unit, 4
Numerals 4 and 45 are cooling blowers, 46 is an inverter (rotation control means), 47 is a control unit (rotation speed control means and silent control means), 48 is an electric box, 50 is a control panel, 53 is a silent switch, and 56 is temperature. Control lever, 57 is a discharge temperature detector, 58 is an indoor heat exchanger temperature detector, 59 is an outdoor heat exchanger temperature detector, 60 is an outdoor temperature detector, 61 is a pressure sensor, 62 is a compressor temperature detector, 63 Is a vehicle speed sensor, and 64 is a vehicle-mounted battery.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-151324 (JP, A) JP-A-5-32121 (JP, A) JP-A-5-147420 (JP, A) JP-A-3-151 87546 (JP, A) JP-A-5-201241 (JP, A) JP-A-4-28949 (JP, A) JP-A-3-36448 (JP, A) JP-A-1-239337 (JP, A) JP-A-4-332349 (JP, A) JP-A-4-144 (JP, A) JP-A 62-156515 (JP, U) JP-A 53-50948 (JP, U) JP-A 62-151114 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60H 1/32 B60H 1/22

Claims (9)

(57) [Claims] 1. A refrigerant mounted on an electric vehicle and flowing through an indoor heat exchanger provided in a refrigerant circuit.
An air conditioner for an electric vehicle that performs an air conditioning operation by performing heat exchange with vehicle interior air passing through the indoor heat exchanger of the air conditioner, wherein a compressor provided in the refrigerant circuit according to a set output of air conditioning control. Rotation control means for controlling the rotation speed of the motor; a vehicle speed sensor for detecting the vehicle speed; rotation speed limiting means for limiting the rotation speed of the compressor motor to a certain rotation speed or less; and a vehicle speed detected by the vehicle speed sensor being predetermined. Silent control means for performing the silent control operation of limiting the rotation speed of the compressor motor to a certain rotation speed or less by driving the rotation control means through the rotation speed limiting means when the speed is equal to or less than the speed. An air conditioner for an electric vehicle, comprising: 2. The noise reduction control means according to claim 1, wherein even when the vehicle speed detected by said vehicle speed sensor is equal to or lower than a predetermined speed, the rotation speed of said compressor motor required for air-conditioning control at that time is equal to or higher than a predetermined upper limit value. 2. The air conditioner for an electric vehicle according to claim 1, wherein said silent control operation is invalidated, and said compressor motor is driven and controlled at a required rotation speed. 3. The silent vehicle according to claim 1, wherein a silent switch is provided in a driver's seat of the electric vehicle, and the control unit executes the silent control operation only when the silent switch is operated. Air conditioner for electric vehicles. 4. A refrigerant mounted on an electric vehicle and flowing through an indoor heat exchanger provided in a refrigerant circuit.
An air conditioner for an electric vehicle that performs an air conditioning operation by performing heat exchange with vehicle interior air passing through the indoor heat exchanger of the air conditioner, wherein a compressor provided in the refrigerant circuit according to a set output of air conditioning control. Rotation control means for controlling the rotation speed of a motor and a cooling blower of the outdoor heat exchanger; a vehicle speed sensor for detecting a vehicle speed; and a rotation speed for limiting the rotation speed of the compressor motor and the cooling blower to a certain rotation speed or less. Limiting means for driving the rotation control means via the rotation speed limiting means when the vehicle speed detected by the vehicle speed sensor is equal to or lower than a predetermined speed, so that the number of rotations of the compressor motor and the cooling blower is constant. An air conditioner for an electric vehicle, comprising: silent control means for performing a silent control operation of limiting the number to a number or less. 5. The noise reduction control means according to claim 1, wherein, even when the vehicle speed detected by said vehicle speed sensor is equal to or lower than a predetermined speed, when the rotation speed of said compressor motor required for air conditioning control at that time is equal to or higher than a predetermined upper limit value. 2. The air conditioner for an electric vehicle according to claim 1, wherein the silent control operation is disabled, and the compressor motor and the cooling blower are driven and controlled at a required number of revolutions. 6. The silent switch provided in a driver's seat portion of the electric vehicle, wherein the control means executes the silent control operation only when the silent switch is operated. Air conditioner for electric vehicles. 7. A refrigerant mounted on an electric vehicle and flowing through an indoor heat exchanger provided in a refrigerant circuit.
An air conditioner for an electric vehicle that performs an air conditioning operation by performing heat exchange with vehicle interior air passing through the indoor heat exchanger of the air conditioner, wherein a compressor provided in the refrigerant circuit according to a set output of air conditioning control. Rotation control means for controlling the number of rotations of the motor, a vehicle speed sensor for detecting a vehicle speed, pressure detection means for detecting the discharge pressure of the compressor, and a required rotation number of the compressor motor according to a set output of air conditioning control. Calculating means for calculating a generated noise level estimated from a discharge pressure of the compressor by a pressure detecting means; rotational speed limiting means for controlling a rotational speed of the compressor motor to decrease; By driving the compressor motor via the rotation speed limiting means when the vehicle speed is equal to or lower than a predetermined speed, Electric motor-vehicle air-conditioning apparatus characterized by comprising a static sound control means for causing the silent control operation constant is be generated noise level to control the rotational speed to be equal to or less than the noise reference level. 8. The electric vehicle according to claim 7, wherein a silent switch is provided in a driver's seat portion of the electric vehicle, and the control unit executes the silent control operation only when the silent switch is operated. Air conditioner. 9. An air conditioner for an electric vehicle having a pre-air-conditioning operation mode in which the vehicle interior is preliminarily air-conditioned when a battery, which is a driving power source of the electric vehicle, is charged. 9. The air conditioner for an electric vehicle according to claim 7, wherein the operation is performed based on a pre-air-conditioning operation noise reference level set lower than the noise reference level when the driving is being performed.