JPH0732864A - Air conditioner for bus vehicle - Google Patents

Abstract

PURPOSE:To provide an air conditioner for a bus vehicle by which outside air can be prevented from flowing in from an inside air intake port. CONSTITUTION:A vinyl hose 21 is arranged to detect a pressure difference between pressure in a cooler case 11 and pressure in a cabin, and a pressure switch 20 is arranged in the middle of it. This pressure switch 20 closes outside air dampers 17 and 18 and opens inside air dampers 15 and 16 when the pressure in the cooler case 11 becomes higher than the pressure in the cabin.

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 a bus vehicle.

[0002]

2. Description of the Related Art Conventionally, ventilation control of an air conditioner for a bus vehicle reduces the amount of outside air when the temperature difference between the inside and outside air in the summer or winter is large in order to prevent a decrease in air conditioning capacity.
The inside air was prioritized to prevent the outside air introduction mode. However, in recent years, since the airtightness of the vehicle has been improved, drafts have been reduced, and the ventilation of the vehicle interior air has often depended on the ventilation capacity of the air conditioner. Furthermore, in order to remove odors caused by cigarettes, liquor, body odor, etc. in the passenger compartment, it is necessary to increase the ventilation capacity of the air conditioning system, and as the cooling and heating capacity increases, the control that prioritizes the introduction of outside air is performed. Has become.

As shown in FIG. 3, the cooler case 11 of the air conditioning unit 1 for an air conditioner for a bus vehicle has outside air dampers 17 and 18 for introducing outside air and inside air dampers 15 and 16 for introducing inside air independently. One of the dampers or both of the dampers are opened according to the inside air introduction mode and the outside air introduction mode. As shown in FIG. 2, the air conditioning unit 1 includes a floor 10 of a bus vehicle.
It is mounted under. Further, the bus vehicle is provided with an exhaustor motor 6 dedicated to ventilation, and by driving this exhaustor motor 6, the air in the vehicle compartment can be ventilated.

[0004]

However, in the above-mentioned device which gives priority to the introduction of the outside air, as shown in FIG.
As shown in, when the outside air is pushed into the cooler case 11 by the wind pressure when the vehicle is traveling at high speed, or the air in the vehicle interior is exhausted to the outside by the exhauster (vehicle interior air exhaust device) 6. In this case, the pressure inside the cooler case 11 becomes higher than the pressure inside the vehicle compartment, and in any case, the air inside the cooler case 11 is discharged from the inside air intake port 4 provided with the inside air dampers 15 and 16 into the vehicle interior. It was found that a backflow phenomenon occurred.

When such a phenomenon occurs, the inside air intake port 4
The outside air hits the inside air sensor 19 installed in the air conditioner, and the inside air sensor 19 detects a temperature including the outside air temperature instead of the actual inside air temperature, which causes a problem that the air conditioner malfunctions. Further, since the inside air intake port 4 is provided at the feet of the passengers and the outside air flows into the inside air intake port 4, the outside air directly hits the passengers, and there is a problem that it is hot in summer and cold in winter. Occurs.

As a method for solving one of these problems, there is a method in which the inside air sensor 19 is installed at a place other than the inside air suction port 4 so that the outside air is not affected even if it flows backward. Since there is no air flow except in the suction port 4, the inside air temperature cannot be accurately detected by the inside air sensor 19. In order to accurately detect the inside air temperature at a place other than the inside air inlet 4, it is necessary to install an aspirator fan that generates an air flow, which increases the number of parts and maintenance items. Moreover, this method has a problem that it is impossible to prevent the influence on passengers.

Therefore, in the present invention, attention is paid to the fact that the outside air flows in from the inside air inlet as described above due to the pressure difference between the pressure inside the cooler case and the pressure inside the vehicle compartment. An object of the present invention is to provide a bus vehicle air conditioner capable of solving the above-mentioned problems by sensing the pressure difference between the internal pressure and the vehicle interior pressure and controlling the ventilation mode, that is, the air conditioning mode. To do.

[0008]

In order to achieve the above object, the present invention has a cooler case having temperature control means for controlling the temperature of the air flowing into the inside, and the air inside the vehicle compartment is taken into the cooler case. An inside air intake, an outside air intake for taking in air outside the vehicle compartment into the cooler case, a first opening / closing means for opening / closing the inside air intake, a second opening / closing means for opening / closing the outside air intake, a vehicle A determination unit that detects the pressure difference between the pressure inside the room and the pressure inside the cooler case and determines which pressure is higher, and this determination unit determines that the pressure inside the cooler case is higher than the pressure inside the vehicle compartment. And a control unit that opens the inside air intake by the first opening / closing means and closes the outside air intake by the second opening / closing means,
An air conditioner for a bus vehicle is provided.

[0009]

According to the bus vehicle air conditioner of the present invention having the above-mentioned structure, the pressure difference between the pressure inside the vehicle compartment and the pressure inside the cooler case is detected by the determination means to determine which pressure is higher. When the determination means determines that the pressure inside the cooler case is higher than the pressure inside the vehicle compartment, the second opening / closing means closes the outside air intake to prevent air from flowing in from the outside air intake. At the same time, the first opening / closing means opens the inside air intake port so that air flows in through the inside air intake port. Therefore, when the pressure inside the cooler case becomes higher than the pressure inside the vehicle compartment, the inside air flows into the cooler case, the pressure inside the cooler case becomes the same as the pressure inside the vehicle compartment, and the outside air enters the inside air intake port. There is no more backflow.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing an air conditioning unit 1 in the present invention. FIG. 2 is a perspective view showing a bus vehicle. FIG. 5 shows the inside air dampers 15, 16 of the air conditioning unit 1,
A circuit diagram for controlling the outside air dampers 17, 18 and the like is shown.

First, the structure of an air conditioner for a bus vehicle will be described with reference to FIG. The air conditioner for a bus vehicle (air conditioner for a bus vehicle) includes air conditioning ducts 2 and 3 and an air conditioning unit 1 for sending temperature-controlled air such as cold air or hot air to the air conditioning ducts 2 and 3. Further, as an exhaust device for exhausting the air in the vehicle compartment, an exhauster 6 is provided at the rear of the vehicle, and an extractor 7 is provided above the left side of the guide seat. Then, the air conditioning unit 1 takes in the air in the vehicle compartment from the inside air intake port 4 provided in the vehicle floor surface 10 and takes in the outside air from the outside air introduction port 5 provided in the vehicle outer plate 8.

The air-conditioning ducts 2 and 3 are provided in the interior of the vehicle from the front to the rear of the air-conditioning duct on both sides of the interior of the vehicle. The upper air conditioning duct 2 is a cooler duct for cold air blown by cold air, and the lower air conditioning duct 3 is a heater duct for warm air blown by warm air. Further, a driver seat duct 50 that blows out cool air toward the driver's seat is connected to the right cooler duct 2, and blows out cool air from the upper right side of the driver seat. A guide seat duct 51 that blows out cool air toward the guide seat is connected to the left cooler duct 2 and blows out cool air from the upper left side of the guide seat.

As shown in the detailed view of FIG. 1, the air conditioning unit 1 has an evaporator 12 and a heater core 13 installed inside a cooler case 11, and takes in vehicle interior air from the inside air intake port 4 into the cooler case 11. Shy air damper 15,
16 and an outside air damper 1 that takes in outside air from the outside air introduction port 5
7 and 18 are provided, and the ratio of the inside and outside air sucked into the cooler case 11 is changed by changing the opening ratio. By closing the inside air dampers 15 and 16, it is possible to prevent the inside air from flowing into the cooler case 11, and by closing the outside air dampers 17 and 18, it is possible to prevent the outside air from flowing into the cooler case. Further, a blower 14 for blowing air into the vehicle compartment is provided with an evaporator 12 and a heater core 13.
Is provided on the downstream side of.

The evaporator 12 constitutes a refrigeration cycle with a refrigerant compressor, a refrigerant condenser and an expansion valve (not shown), and cools the air passing through the evaporator 12. The engine core water flows into the heater core 13 and warms the air passing therethrough. This evaporator 12 and heater core 13
To control the temperature of the air. Further, in order to detect the pressure difference between the pressure inside the cooler case 11 and the pressure inside the vehicle compartment, a vinyl hose 21 that spans the inside of the cooler case 11 and the vehicle compartment is installed, and a diaphragm-type pressure switch 20 is provided between them. Install. The vinyl hose 21 has a hole (static pressure hole) with a diameter of about 1 mm so that it is not affected by dynamic pressure.
22 is provided.

Next, the inside air dampers 15 and 1 will be described with reference to FIG.
6 and the control circuit for controlling the driving of the outside air dampers 17 and 18 will be described. As shown in FIG. 5, the control circuit 100 supplies the power source of the battery 101 to the air conditioner equipment component 102 such as the blower 14 via the contact point 105a of the main relay to the battery 101. Air conditioner parts 10
An air conditioner control amplifier 103 is connected to 2 and performs control described later.

The air conditioner control amplifier 103 is connected so that the signal of the thermistor 119 in the inside air sensor 19 for detecting the temperature in the vehicle compartment is inputted, and the thermistor in the outside air sensor 23 for detecting the outside air temperature. They are connected so that signals of 123 are input. The air conditioner control amplifier 103 is supplied with power from the battery 101 via the main switch 104. At the same time, the power of the battery 101 is supplied to the main relay coil 105 via the main switch 104. The main switch 104 is provided on the control panel 52 provided in the driver's seat shown in FIG. When power is supplied to the main relay coil 105, the main relay contact 10
5a closes and becomes conductive.

Further, the servo motor 115 for driving the inside air damper 15, the servo motor 116 for driving the inside air damper 16, and the servo motor 11 for driving the outside air damper 17 are provided.
7 and a servomotor 118 that drives the outside air damper 18 are connected to the control amplifier 103. The contact 120 in the pressure switch 20 is connected to the control amplifier 103.

Next, the operation of the air conditioner for a bus vehicle having the above structure will be described. In the bus vehicle air conditioner, when the main switch 104 is closed, the air conditioner control amplifier 1
03 is supplied with power and main relay coil 1
Power is supplied to the main relay contact 105
When a is closed, power is supplied to the air conditioner component 102.

Normally, the blower 4 cools the cooler case 11
Since the inside air is sucked, the pressure is lower than the vehicle interior pressure, and the pressure switch inner contact 120 in the pressure switch 20 is in the open state (OFF). in this case,
The ventilation mode is determined according to a predetermined ventilation mode or the degree of contamination of air inside and outside the vehicle, and the servo motor 11
The inside air damper 1 is driven by driving 5, 116, 117 and 118.
5, 16 and the outside air dampers 17, 18 are controlled.

However, when the pressure difference in the cooler case 11 exceeds the reference value (for example, 3 mmAg) due to the traveling dynamic pressure or the discharge of air inside the vehicle, the diaphragm in the pressure switch 20 is reversed. , The contact 120 is closed (ON). When the air conditioner control amplifier 103 detects the signal of the closed state of the contact 120, it judges that the backflow of the outside air is “present”, and the pressure switch 20 is turned on in order to prevent the error due to the outside air temperature detection of the inside air sensor 19. "
While maintaining the air conditioning mode immediately before, the outside air dampers 17 and 18 are closed and the inside air dampers 15 and 16 are opened to prevent backflow of outside air. By sucking the inside air in this way, there is no pressure reversal and no backflow of outside air. At this time, the pressure switch 20 is turned off, but in order to prevent hunting of the damper, the air conditioning mode and the inside air mode are maintained for a certain period of time (for example, 2 minutes), and then the normal air conditioning mode and the ventilation mode are set. Return to mode.

The output difference between the outside air sensor 23 and the inside air sensor 19, that is, the inside and outside air temperature difference, the change rate of the output value of the inside air sensor 19 and the like are used as materials for determining the outside air backflow when the contact 120 is closed. By adding it, more precise control can be performed, and the servo motors 115, 116, 117, 1
The number of activations of 18 can be reduced. As described above, the diaphragm type pressure switch is installed, and the simple structure in which the control of the air-conditioning mode and the ventilation mode is restricted based on the signal is a simple structure, and the outside air flows in from the inside air intake port 4 Can be solved reliably.

Although the diaphragm type pressure switch is used in the above embodiment, the invention is not limited to this.
A pressure sensor for detecting the pressure inside the cooler case 11 and a pressure sensor for detecting the pressure inside the vehicle compartment are provided, and the inside air dampers 15 and 16 are calculated by calculating the pressure difference between the pressure sensors.
Alternatively, the outside air dampers 17 and 18 may be controlled.

[0023]

As described above, according to the air conditioner for a bus vehicle of the present invention, when the pressure inside the cooler case is higher than the pressure inside the passenger compartment, air is made to flow in from the inside air intake port, and the outside air The intake is closed to prevent air from flowing in from the outside air intake. Therefore, when the pressure inside the cooler case becomes higher than the pressure inside the vehicle compartment, the inside air flows into the cooler case, the pressure inside the cooler case becomes the same as the pressure inside the vehicle compartment, and the outside air enters the inside air intake port. There is no more backflow. Therefore, the outside air is not blown directly to the passenger, and the temperature control and ventilation control of the vehicle interior can be performed based on the accurate inside air temperature.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of an air conditioner for a bus vehicle of the present invention.

FIG. 2 is a perspective view showing a bus vehicle.

FIG. 3 is a diagram showing a conventional bus vehicle air conditioner.

FIG. 4 is a diagram showing a conventional bus vehicle air conditioner.

FIG. 5 is a diagram showing a control circuit of the bus vehicle air conditioner of the present invention.

[Explanation of symbols]

 1 Air Conditioning Unit 4 Inside Air Suction Port 5 Outside Air Inlet 12 Evaporator (Temperature Control Means) 13 Heater Core (Temperature Control Means) 14 Blower (Blower Means) 15, 16 Inside Air Damper (First Opening and Closing Means) 17, 18 Outside Air Damper (No. 1) 2 open / close means) 19 inside air sensor 20 pressure switch (judging means) 21 vinyl hose 22 static pressure hole 23 outside air sensor 100 control circuit (control section)

Claims (1)

[Claims] 1. A cooler case having a temperature control means for controlling the temperature of air flowing into the inside, an inside air intake for taking in the air inside the vehicle interior into the cooler case, and an air outside the vehicle inside the cooler case. An outside air intake, a first opening / closing means for opening / closing the inside air intake, a second opening / closing means for opening / closing the outside air intake, and a pressure difference between the pressure inside the vehicle compartment and the pressure inside the cooler case are detected. A determination means for determining which pressure is higher, and when the determination means determines that the pressure in the cooler case is higher than the pressure in the vehicle compartment, the first opening / closing means opens the inside air intake port. A controller for closing the outside air intake by the second opening / closing means, and a bus vehicle air conditioner.