JPH08132854A - Air conditioner - Google Patents

Abstract

PURPOSE: To promote cleaning of an air filter and heat exchangers such as an evaporator and a heater core by correctly informing dirt of them. CONSTITUTION: Pressure difference between the upper stream side of an air filter 39 and the lower stream side of a heater core 18 is detected by a detecting means 40, and when the detected value is judged to be over a reference value by a judging means 41, it is informed by an informing means 43.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art One example of a conventional air conditioner of this type is shown in FIG.
And shown in FIG. As shown in FIG.
The air conditioner unit 1 is installed in the lower part of 100.
Cold air blowout ducts 4 extend in the front-rear direction on both sides near the ceiling in the passenger compartment 2, and warm air blowout ducts 6 extend in the front-rear direction on both sides near the inner floor of the passenger compartment 2.

During the cooling operation, the cold air generated in the air conditioner unit 1 branches through the underfloor duct 22, passes through the pair of rising ducts 3 and enters the cold air blowing duct 4, and the cold air blowing duct 4 has a predetermined interval before and after. The air is blown into the vehicle interior 2 from a large number of air outlets 5 that are formed apart from each other.

During the heating operation, the warm air generated in the air conditioner unit 1 passes through the underfloor duct 22 and the rising duct 3 and enters the warm air blowing duct 6, and the warm air blowing duct 6 is spaced forward and backward by a predetermined distance. From the numerous outlets 8 formed to the passenger compartment 2
It is blown out inside.

FIG. 4 shows a system diagram of the air conditioner. A sub engine 10 is installed inside the air conditioner unit 1, and a compressor 11 is installed by the sub engine 10.
And the condenser fan 12 which also functions as a radiator fan is driven.

When the compressor 11 is driven, the refrigerant discharged from the compressor 11 enters the condenser 13,
Here, the condenser fan 12 radiates heat to the outside air to condense and liquefy it. The liquid refrigerant enters the evaporator 16 via the receiver 14 and the expansion valve 15, where it is evaporated and vaporized by exchanging heat with the air inside the vehicle or the outside air blown by the evaporator fan 9, and then returns to the compressor 11.

Inside the casing 17, an evaporator fan 9, an evaporator 16, a heater coil 18, an inside / outside air switching damper 19, an air filter 39 and the like are housed. By switching the inside / outside air switching damper 19 while the evaporator fan 9 is operating, the air inside the vehicle compartment is sucked into the casing 17 from the inside air inlet 20 and the outside air is sucked into the casing 17 from the outside air inlet 21.

The air sucked into the casing 17 becomes conditioned air by passing through the air filter 39, the evaporator 16 and the heater coil 18, and the conditioned air is urged by the evaporator fan 9 and then from the blowout port 37. It is blown out, branches through the underfloor duct 22, and passes through the pair of rising ducts 3 when the up / down switching damper 7 is in the position shown by the broken line. When the up / down switching damper 7 is in the position shown by the solid line, It is sent to the hot air duct 6.

During heating operation, the sub-engine 10 is stopped, the fan motor 30 is driven, and the on-off valves 35, 36 are driven.
Is opened. As a result, a part of the high-temperature engine cooling water that has flowed out of the main running engine 32 is supplied to the heater coil 18 via the opening / closing valve 36 and the flow rate control valve 38, and the temperature is lowered by radiating heat there, and then the opening / closing valve 35 is opened. After that, it returns to the main engine 32. Most of the high-temperature engine cooling water returns to the main engine 32 after radiating heat to the outside air blown by the radiator fan 33 by the radiator 34.

When the fan motor 30 is driven,
The power from this is transmitted to the evaporator fan 9 via the drive shaft 26, the pulley 27, the belt 28, and the pulley 29 to rotate it. At this time, magnet clutch
25 is cut off.

During the cooling operation, the sub engine 10 is driven. The power of the sub engine 10 is the pulley 23, the belt 24, the magnet clutch 25, the drive shaft 26,
It is transmitted to the evaporator fan 9 through the pulley 27, the belt 28, and the pulley 29 to rotate it. At this time, since the fan motor 30 is not energized, the fan motor 30 merely functions as a bearing.

[0012]

In the conventional air conditioner described above, dust contained in the air is accumulated on the surfaces of the evaporator 16 and the heater coil 18 to block the air flow path thereof, or its heat transfer performance. In order to suppress lowering, the air filter 39 is arranged on the upstream side of the evaporator 16, the dust contained in the air is trapped by the air filter 39, and periodically every time a predetermined operating time elapses. Although it was recommended to clean the air filter 39, the evaporator 16 and the heater coil 18, the power consumption of the evaporator fan 9 increases due to the delay of the cleaning time, and the amount of air blown from the air conditioner unit 1 decreases. ,
There is a possibility that the performance of the air conditioner may deteriorate due to the heat exchange capacity of the evaporator 16 and the heater coil 18 decreasing.

[0013]

The present invention has been invented to solve the above-mentioned problems, and the gist of the first invention is to provide an air filter and an air filter in an air passage ventilated by a fan. In an air conditioner provided with a heat exchanger, means for detecting a pressure difference between the upstream side of the air filter and the downstream side of the heat exchanger, and whether or not the detected value is a reference value or more. The air conditioner is characterized by comprising a judging means for judging and a notifying means for notifying the dirt of the air filter and the heat exchanger when the detected value is judged to be a reference value or more by the judging means.

According to a second aspect of the invention, in an air conditioner in which an air filter and a heat exchanger are arranged in an air passage ventilated by a fan, a space between the air filter and the heat exchanger is provided. A sensor for detecting fine particles passing through the air filter and determining means for determining whether or not a detection value of the sensor is a reference value or more, and the determination means determines that the detection value is a reference value or more. The air conditioner is characterized in that it is provided with an informing means for informing of the contamination of the heat exchanger when it is turned off.

[0015]

In the first aspect of the present invention, when the detected pressure difference is determined to be equal to or greater than the reference value, the notification means notifies the dirt of the heat exchanger.

In the second aspect of the present invention, when the particulates that have passed through the air filter are determined to be above the reference value, the notification means notifies the dirt of the heat exchanger.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A first embodiment of the invention is shown in FIG. The detection values of the pressure sensor 44 disposed in the upstream air passage of the air filter 39 and the pressure sensor 45 disposed in the downstream air passage of the heater coil 18 are input to the pressure difference detection means 40, where the air filter is provided. 39, evaporator 16 and heater coil 18
The pressure difference before and after is detected.

When the detected pressure difference is input to the determination means 41, the determination means 41 compares it with the reference value input from the setting means 42 to determine whether it is equal to or more than the reference value, and the pressure difference is the reference value. When it is determined that the above, it outputs to the notification means 43. When this command is input, the notification means 43 notifies that the heat exchanger is dirty.

Since the ventilation resistance of the heat exchanger increases as the dirt of the heat exchanger increases, the dirt of the heat exchanger can be accurately detected by detecting the pressure difference before and after that. Therefore, since the notification means 43 can notify the fouling of the heat exchanger, cleaning of the heat exchanger can be promoted, and as a result, deterioration of the performance of the air conditioner due to the fouling of the heat exchanger can be prevented.

The pressure difference before and after the heat exchanger may be detected by detecting the air flow rate and the flow velocity on the downstream side of the heater coil 18, the rotation speed of the evaporator fan 9, and the like.

A second embodiment of the invention is shown in FIG. The particles passing through the air filter 39 are detected by a photo sensor 50 arranged between the air filter 39 and the evaporator 16.

When the detected fine particles are inputted to the judging means 51, the judging means 51 judges whether the detected value is equal to or more than the reference value inputted from the setting means 52. The determination means 52 outputs to the notification means 53 when it determines that the detected value is greater than or equal to the reference value, and notifies the notification means.
53 informs the heat exchanger of contamination.

[0023]

In the present invention, since the notification of the contamination of the heat exchanger is given by the notifying means, the cleaning of the air filter and the heat exchanger is promoted, and therefore, the performance deterioration of the air conditioner can be prevented in advance. .

[Brief description of drawings]

FIG. 1 is a system diagram showing a first embodiment of the present invention.

FIG. 2 is a system diagram showing a second embodiment of the present invention.

FIG. 3 is a perspective view of a conventional air conditioner.

FIG. 4 is a system diagram of a conventional air conditioner.

[Explanation of symbols]

 9 Juan 39 Air filter 16, 18 Heat exchanger 44, 45 Pressure sensor

Claims (2)

[Claims] 1. A pressure difference between an upstream side of the air filter and a downstream side of the heat exchanger in an air conditioner having an air filter and a heat exchanger arranged in an air passage ventilated by a fan. To detect whether the detected value is greater than or equal to a reference value, and when the determination value is determined to be greater than or equal to the reference value, the air filter and the heat exchanger are informed of contamination. An air conditioner comprising: 2. An air conditioner in which an air filter and a heat exchanger are provided in an air passage ventilated by a fan, and the air filter is provided between the air filter and the heat exchanger. A sensor that detects the passing particles,
And a determination means for determining whether or not the detection value of the sensor is equal to or greater than a reference value, and an informing means for informing of the contamination of the heat exchanger when the determination value is determined to be equal to or greater than the reference value. An air conditioner characterized by.