JPS5993160A - Air conditioner for automobile - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioner for an automobile, which is equipped with an electric blower for cooling condensation in a refrigeration cycle, and whose rotational speed can be changed by the high pressure of the refrigeration cycle.

In order to save power, conventional devices operate at high speed when the engine water temperature or high-pressure side pressure exceeds a predetermined value, and operate at low speed only when both water temperature and pressure fall below a predetermined value. Therefore, when the refrigeration cycle is started, there is a delay in the response of the high pressure, so the electric fan operates at a low speed, which may impair the cool-down characteristics.

The present invention aims to solve the above problems. Therefore, the present invention operates the electric fan at high speed when starting the refrigeration cycle.
After a predetermined delay time, a low-speed (or high-speed) blower is activated depending on the water temperature, pressure, etc. According to the present invention, the condenser cooling capacity at the initial stage of cool-down can be improved, and the cool-down characteristics can be improved.

To explain the present invention with reference to the embodiment shown in figure ff11, 0 is the battery terminal, ■ is Keith Inochi (IG), and 2 is the empty a
Birch fan relay, 3 is a fan switch operated manually or automatically, 4 is an air conditioning blower, 5 is a resistance for adjusting its speed, 61J air conditioner switch, 7 is a thermostat 1-1
Reference numeral 8 denotes an electromagnetic clutch that connects the compressor 8Δ to the engine (not shown). Here, when the switch 1 is closed, if the Fasys Isoji 3 is turned on to either low speed (Lo), medium speed (Me), or high speed (Ili), the contact of the relay 2 will close and the blower 4 will turn on the fan switch 3. Rotates at a speed appropriate to the position. Furthermore, when the air conditioner switch 6 is turned on, the compressor 8A starts a refrigerating cycle (not shown), causing the condenser to perform a heat dissipation action and the evaporator to perform a heat absorption action. The thermostat 7 opens when the evaporator becomes supercooled, thereby adjusting the temperature to stop the heat absorption action.

9 is an electric blower for cooling the condenser, which also serves to cool the engine radiator if necessary. This air blower 11'), 9
is connected in parallel with the clutch 8, and is energized and rotated when the freezing cycle is activated to cool the condenser. 11 is a speed switching relay for the blower 9, ■2 is a speed adjustment resistor,
When the contact of the relay 11 is open, the air blower TA9 rotates at high speed, and when it is open, it rotates at high speed due to the step-down action of the resistor I2.

However, C, the condenser cooling blower 9 is cold'/81j
The pressure switch 13 installed in the 1Qij ball piping (receiver expansion valve l11) in the cycle activates the relay 11 and closes the contacts when the pressure exceeds the set pressure (for example, 15 kg/cJ), so it operates at high speed and closes the contacts. At less than the pressure (e.g. I Okg/cJ) (J relay 11
becomes inactive and operates at low speed. This is the condenser cooling fan 9 when the cooling load is large and the high pressure rises.
This is to operate at high speed to improve cooling capacity and reduce high pressure. In addition, if necessary, pressure gas isodji 13
Hysteresis is applied to the operating set point.

Around this time, when the air conditioner is started, the odor is 1 "G positive pressure".
Since it takes time for the air to rise to the second temperature, when particularly rapid cooling is required, such as after parking under the hot summer sun, the condenser cooling fan 9 does not operate at high speed, but instead operates at Lo for a while, resulting in cooling capacity. will be in short supply. Therefore, this device is provided with a timer circuit 10, and when the near cons switch 6 is turned on, the iJ output cotton 10 is
By setting Δ to the ground level, the relay II is forcibly activated and the blower 9 is activated at high speed.

The present invention can be implemented using the microcomputer 15 as shown in FIG. 2, and the program flow in that case is not shown in the flowchart 1 of FIG. First, in step 1 (11 (processed by timer interrupt if necessary), each switch input and high pressure state are read. Next, proceed to step 1 () 2, and set flag F to 1. In step 103, Determine whether the near cons/inochiro is on or off, and if it is off, step 112 is set to 3 (6 blowers 9 and relay 14Δ is set to A) to stop 1. At the same time, relay 14B is turned off. The compressor is stopped by shutting off the ζ Clasodge 8.

If the air conditioner switch 6 is on, the process advances to step 104. In step 104, it is determined whether flag F has been marked. If F20 is not loaded, the process goes to step 109, and if F=1 is installed, the process goes to step 105, where the relay 11 is turned on and the blower 9 is turned on.
is operated at high speed, and relays 148 and B are turned on to connect clutch 8 and operate compressor 8Δ.

Next, the process proceeds to step 106, where the built-in timer counter is activated and waits until the value reaches or exceeds a predetermined value.

When the timer call and value exceed a predetermined value, step 108
Proceed to step 4 and set flag F to 11 (F=0). Next, the process advances to step 109, and when the high-speed H1i) and 'I'11 are constant at a predetermined value C or higher due to the high pressure of the refrigeration/cycle, the process proceeds to step 11 (+), where the pressure gradually decreases. When the pressure falls below the predetermined pressure B (lower than eC), the low pressure L
It is determined as o and the process proceeds to step 111. In step 110, the blower 9 is operated at the 41st speed, the clutch 8 is engaged, and the compressor 88 is moved 1'.
is connected to operate the compressor 8A.

Note that when the blower 9 also serves as cooling for the engine radiator, the microcontroller manually inputs the signal from the engine coolant temperature sensor at step 15, and at the step 109, changes the value of the coolant salinity to °C. Also 'l'lJ determined,
The high and low speeds of the blower 9 may be determined based on both conditions. Condition settings in this case may be the same as those of the known technique mentioned at the beginning.

Further, the time counted by the timer can be changed depending on the temperature inside the vehicle interior or the temperature outside the vehicle interior.

As described above, the present invention can improve the capacitor cooling capacity at the time of starting the refrigeration cycle, and can improve the cool-down characteristics.

[Brief explanation of drawings]

FIG. 1 is an electrical wiring diagram of the first embodiment of the present invention, FIG. 2 is a configuration diagram of the second embodiment, and FIG. 3 is an explanatory diagram of a control program of the second embodiment. 6... Air conditioner switch, 8... Clutch, 9...
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...Pressure J Suisoji, 14A, 14B...Relay, 1
5... Ma iku rI computer. Representative Patent Attorney Takashi Okabej: 2 1'J Fl; 3 +'A1

Claims (1)

[Claims] In an automotive air conditioner that has an electric blower for cooling a condenser and is capable of switching the rotational speed of the blower to two or more stages depending on the high pressure of the refrigeration cycle, in response to the start-up of the refrigeration cycle, the air conditioner is operated for a predetermined period of time regardless of the high pressure. Only operate the condenser cooling blower at high speed.
An automotive air conditioner equipped with an electric circuit.