JPH08175152A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE: To reduce the noise associated with the operation of a condenser fan when a vehicle is air-conditioned while it is parked at night. CONSTITUTION: An air conditioner is provided with a parking brake signal transmitting means 21 to detect that a parking brake is applied while a vehicle is parked and transmit the parking brake ON signal, a light signal transmitting means 22 to detect that a night light is lit and transmit the light ON signal, a night parking judging means 23 to judge that the vehicle is in the night parking condition when the parking brake ON signal and the light ON signal are received, and a fan speed switching means 24. The fan speed switching means 24 decelerates fan motors 5a, 5b for a condenser by making a switching from a constant speed operation circuit 25 to a deceleration circuit 26 when the night parking signal is received from the night parking judging means 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner suitable for buses and the like.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a system diagram of a conventional vehicle air conditioner of this type. In FIG. 3, 1 is an engine for driving a vehicle, 2a and 2b are compressors driven by the engine 1, 3 is a condenser, 4a and 4b are condenser fans for blowing outside air to the condenser 3, and condenser condensers. It is driven by motors 5a and 5b. An evaporator unit 6 includes an expansion valve 7, an evaporator 8 therein, evaporator fans 9a and 9b for blowing air into the vehicle compartment, and evaporator fan motors 10a and 10b for driving them. It is arranged.

Further, 11 is a generator driven by the engine 1, 12 is a battery charged by the generator 11,
Fan motors 5a, 5b for starting the engine 1 and for capacitors
It also serves as a power source for driving the fan motors 10a and 10b for the evaporator.

When the compressors 2a and 2b are driven by the engine 1, the high-temperature and high-pressure refrigerant gas discharged from the compressors merges into the condenser 3 as shown by the solid arrows, and from the condenser fans 4a and 4b. By exchanging heat with the outside air to be sent, it is condensed and liquefied to become a refrigerant liquid.
This refrigerant liquid enters the expansion valve 7, where it is adiabatically expanded into a low-temperature low-pressure gas-liquid two-phase state.

The gas-liquid two-phase refrigerant enters the evaporator 8, where the vehicle interior air sent from the evaporator fans 9a and 9b is cooled to evaporate and become a low-temperature low-pressure refrigerant gas. Then, this refrigerant gas is branched and sucked by the compressors 2a and 2b and compressed again. The air cooled in the evaporator 8 is blown into the vehicle compartment through a duct (not shown).

[0006]

In the above conventional vehicle air conditioner, the rotational speeds of the condenser fan motors 5a and 5b are set to a constant rotational speed that can ensure an air volume corresponding to the maximum load of the condenser 3. There is. In addition, the compressor 2a,
In 2b, the number of operating vehicles is controlled according to the cooling load in the passenger compartment.

Therefore, in the cooling operation during parking at night, the engine 1 becomes an idling operation and the rotation speeds of the compressors 2a and 2b decrease, the outside air temperature decreases, and the sunshine disappears. Is reduced, and one compressor is stopped accordingly.

Then, the amount of circulation of the refrigerant flowing through the condenser 3 decreases, so that the load on the condenser 3 decreases, and
Since the outside air temperature is lowered, the heat exchange performance between the outside air and the refrigerant in the condenser 3 is improved, and the required air volume of the condenser fans 4a and 4b is reduced.

However, in specially equipped vehicles such as security vehicles, TV broadcasting vehicles, and library vehicles, the parking time is long, and cooling operation during parking is indispensable. Especially, during cooling operation during night parking, the outside temperature decreases. Therefore, the load of the capacitor 3 becomes smaller than the maximum load. Therefore, in such a case, there is a problem in that the amount of air blown by the condenser fans 4a and 4b becomes excessively large, and a complaint of noise is likely to be caused particularly at night and in a residential area.

[0010]

SUMMARY OF THE INVENTION The present invention has been invented to solve the above problems, and its gist is to provide a capacitor for driving a capacitor fan for blowing outside air to the capacitor. In a vehicle air conditioner equipped with a fan motor, etc., detects that the parking brake is applied when the vehicle is parked and sends a parking brake ON signal, and detects that the night illumination lamp is turned on. At the same time, when it receives both the parking brake ON signal and the illumination lamp ON signal, it determines that the vehicle is in the night parking state and transmits the signal. It comprises a parking judgment means, a constant speed operation circuit for directly applying the full voltage to the condenser fan motor, and a deceleration operation circuit for applying it through a resistor. A vehicle air conditioner characterized by comprising a fan motor speed switching means for switching the constant speed operation circuit to the deceleration operation circuit to reduce the rotation speed of the condenser fan motor when a night-time parking signal is received. is there.

In the deceleration operation circuit, some capacitor fan motors of a plurality of capacitor fan motors are stopped, and at the same time, a voltage is applied to all or part of the remaining capacitor fan motors via resistors. It can also be configured as follows.

[0012]

In the present invention, the parking brake ON signal and the illumination lamp ON are supplied during the cooling operation of the vehicle at night and during parking.
When the signal is received, the constant speed operation circuit of the fan motor speed switching means is switched to the deceleration operation circuit, the voltage applied to the capacitor fan motor is reduced, and the capacitor fan is decelerated.

When switching to the deceleration operation circuit, a part of a plurality of capacitor fan motors for capacitors is stopped and simultaneously a voltage is applied to all or part of the remaining capacitor fan motors through resistors. By doing so, this can be decelerated.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT One embodiment of the present invention is shown in FIGS.
FIG. 1 is a control block diagram, and FIG. 2 is an electrical control circuit diagram. The refrigerant circuit is the same as the conventional one shown in FIG.

In FIG. 1, reference numeral 21 denotes a parking brake that is detected when the parking brake is applied when the vehicle is parked.
Parking brake signal transmitting means for transmitting an ON signal, 22 is an illumination lamp that detects when the illumination lamp of a night vehicle is turned on
It is a lighting signal transmission means for transmitting an ON signal, and each signal is output to the night / parking determination means 23.

When the night / parking judging means 23 receives both the parking brake ON signal and the illumination lamp ON signal, it judges that the vehicle is in the night parking state and outputs the signal to the fan motor speed switching means 24.

The fan motor speed switching means 24 is interposed in the power supply circuits of the condenser fan motors 5a and 5b, and includes a constant speed operation circuit 25 for directly applying the full voltage to the condenser fan motors 5a and 5b and a resistor. It has a deceleration operation circuit 26 which is applied via. When the fan motor speed switching means 24 receives a signal from the night / parking determination means 23 indicating that the vehicle is in the night parking state, the constant speed operation circuit 25 to the deceleration operation circuit 26.
Switch to.

As shown in FIG. 2, night / parking judging means 23
Is provided with a switch 27 that is closed in response to a parking brake ON signal, a switch 28 that is closed in response to an illumination lamp ON signal, and an auxiliary relay 29 that are connected in series to the power supply circuit. The constant speed operation circuit 25 of the fan motor speed switching means 24 has ab contact 30 of the auxiliary relay 29, and the deceleration operation circuit 26 has an a contact 31, a resistor 32 and a diode 33 of the auxiliary relay 29. .

However, in normal cooling operation, both or one of the switches 27 and 28 is open, and therefore the auxiliary relay 29 is not excited and its b contact 30 is closed.
The a contact 31 is open. Thus, the current from the power supply 34 is applied to the fan motor 5a via the b-contact 30 of the auxiliary relay 29 and simultaneously to the fan motor 5b via the diode 33, as shown by the solid line arrow. Since the entire voltage of the power supply 34 is directly applied to 5b, these fan motors 5a and 5b are operated at a constant speed.

When the vehicle is parked at night and the parking brake is applied and the illumination lamp is turned on, the switch 27 and the switch 28 are turned on.
Are closed and the auxiliary relay 29 is excited. Then, the b contact 30 of the auxiliary relay 29 is opened and the a contact 31 thereof is closed. Thus, the current to the fan motor 5a is a diode
Since it is cut off by 33, the fan motor 5a is stopped, and the fan motor 5b is connected to the a contact 31 as shown by the broken line arrow.
Since a current flows through the resistor 32 and the resistor 32, the applied voltage is reduced and the fan motor 5b is decelerated.

When only one condenser fan motor is used, it is decelerated. In the case of two units, as shown in the above embodiment, one unit may be stopped and the other unit may be decelerated, but one unit may be stopped and the other unit may be operated at a constant speed, or
The platform can be slowed down as well. Juan Motor has 3
If the number of units is equal to or more than the number of units, these may be decelerated by various combinations.

The deceleration speed of the condenser fan motor may be determined in consideration of the operating condition of the air conditioner and the effect of noise reduction.

[0023]

According to the present invention, the constant speed operation circuit of the fan motor speed switching means is switched to the deceleration operation circuit when the parking brake ON signal and the illumination light ON signal are received in the cooling operation of the vehicle at night / parking. Instead, the voltage applied to the condenser fan motor decreases, and the condenser fan is decelerated. Therefore, the amount of air flowing through the condenser is reduced and the noise is reduced, so that the noise complaint in the residential area can be eliminated.

[Brief description of drawings]

FIG. 1 is a control block diagram showing an embodiment of the present invention.

FIG. 2 is an electrical control circuit diagram of the above embodiment.

FIG. 3 is a system diagram of a conventional vehicle air conditioner.

[Explanation of symbols]

 1 Engine 2a, 2b Compressor 3 Condenser 4a, 4b Condenser fan 5a, 5b Condenser fan motor 11 Generator 12 Battery 21 Parking brake signal transmitting means 22 Illuminating light signal transmitting means 23 Night / parking determination means 24 Juan motor speed switching Means 25 Constant speed operation circuit 26 Deceleration operation circuit 32 Resistor 33 Diode

Claims (2)

[Claims] 1. A vehicle air-conditioning system comprising a condenser fan motor for driving a condenser fan for blowing outside air to the condenser, the parking brake being detected when the parking brake is applied when the vehicle is parked. The parking brake signal transmitting means for transmitting the ON signal, the lighting signal transmitting means for detecting that the night lighting is turned on and transmitting the lighting ON signal, both the parking brake ON signal and the lighting ON signal When received, the vehicle is judged to be in the night-time parking state and the signal is transmitted to the night-time parking judgment means, and the constant voltage operation circuit for directly applying the full voltage to the condenser fan motor is applied through the resistor. When the night parking signal is received from the night-time parking judging means, the constant speed operation circuit is switched to the deceleration operation circuit, and the condenser far is constituted. Air conditioning system, characterized in that a fan motor speed switching means which allowed to reduce the rotational speed of the motor. 2. The deceleration operation circuit stops a part of a plurality of capacitor fan motors out of a plurality of capacitor fan motors and, at the same time, supplies a voltage to all or part of the remaining capacitor fan motors via resistors. The vehicle air conditioner according to claim 1, wherein the air conditioner is applied.