JPS6033120A - Controller for blow-out temperature in air conditioner for car - Google Patents

Abstract

PURPOSE:To improve efficiency and reduce the operation rate of a compressor to the min. by calculating a set temp. according to the outside air temp. and the input to a set temp. switch and stopping the compressor when the exit temp. of an evaporator becomes lower than the set temp., thus eliminating the influence of the outside air temp. CONSTITUTION:The outside air temp. 16 is input into a set temp. calculation part 12 through a detection part 11. While, the exit temp. 17 of an evaporator is input into a judging part 14 through a detection part 13. Further, the operation mode signal of a set temp. switch 18 is input into the set temp. calculation part 12. Said calculation part 12 determines a set temp. according to the outside air temp. 16 and the signal of the set temp. switch 18, and sends the set temp. into the judging part 14. The judging part 14 compares the set temp. with the exit temp. 17 of the evaporator, and when the exit temp. 17 lowers below the set temp., an electromagnetic clutch 19 is operated to stop a compressor. Therefore, the efficient cooling efficiency can be secured for the variation of the outside air temp., and the operation rate of the compressor can be reduced to the min.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an air outlet temperature control device for a vehicle air conditioner.

Structure of conventional example and its problems In recent years, the first blowout temperature control device for vehicle air conditioners has been developed.
As shown in the figure, air cooled by an evaporator 1 is warmed by a mix damper 2, part or all of which is warmed by a heater core 3, and then mixed with the cooled air again to adjust the blowout temperature. A regulating air mix structure is used. At this time, in order to control the evaporator outlet temperature, an evaporator temperature detection element 4 is attached to the outlet of the evaporator 1, and the evaporator outlet temperature is detected by the control device 6. When the evaporator outlet temperature becomes lower than the evaporator outlet temperature, The power supply to the electromagnetic clutch 6 is stopped, and the compressor is stopped. When the evaporator outlet temperature becomes higher than the set temperature again, the electromagnetic clutch is energized to operate the compressor. Actually, in order to prevent the electromagnetic clutch 6 from repeatedly operating and stopping frequently, a temperature difference is provided between the set temperature and the temperature at which the compressor operates.

The set temperature is determined as shown in FIG. In summer when the outside air temperature is high and a low blowout temperature is required, the first temperature T1 is set slightly higher than the freezing temperature to prevent the evaporator 1 from freezing.
The compressor is stopped at the second temperature T1, which is slightly higher than the first temperature T1.
The compressor is operated at a temperature T2 of . At this set temperature,
The compressor is operated at maximum capacity. However, when the outside air temperature is low, such a low blowout temperature is not required. If the set temperature remains the same, you will have to increase the amount of air flowing to the heater core 3 by moving Mix Danno (2) to increase the Suita temperature. Therefore, if you raise the set temperature so that the compressor stops at the third temperature T3 and starts operating at the fourth temperature T4, the blowout temperature will decrease and the compressor operating rate will decrease. It also saves time and reduces energy waste.

However, with this control, even if the set temperature is set high, if the outside temperature gets too low, the cooling capacity will be insufficient, so the set temperature must be lowered immediately.

Therefore, the period of use at a high set temperature is short and sufficient energy saving effect cannot be obtained.

Purpose of the Invention The present invention solves the above-mentioned problems of the conventional technology, and provides efficient air conditioning by ensuring the necessary cooling capacity even with changes in outside temperature, and by minimizing the operating rate of the compressor. The purpose is to do something.

Structure of the Invention To achieve this object, the present invention provides an outside temperature detection element that detects the temperature outside the vehicle interior, an evaporator temperature detection element that detects the temperature inside or at the outlet of the evaporator, and a set temperature switch that switches the set temperature. a switch, a control device that determines and outputs signals from both the temperature detection elements and the set temperature changeover switch, and an electromagnetic clutch that operates the compressor intermittently based on the output signal of the control device, and the control device further includes: A set temperature calculating section is provided to calculate a set temperature based on the input of the set temperature changeover switch and the outside air temperature, and the compressor is stopped when the evaporator outlet temperature reaches the set temperature or less.

With this configuration, a high set temperature can be changed depending on the outside temperature.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3 to 6.

In FIG. 3, the control unit 1o includes an outside temperature detection unit 11, a set temperature calculation unit 12. Evaporator outlet temperature detection section 131 determination section 14. It is composed of an electromagnetic clutch drive section 16. 16 is an outside air temperature detection element that detects the outside air temperature; 17 is an evaporator temperature detection element that detects the temperature of the evaporator or the outlet temperature;
8 is a switch for changing the set temperature. Electromagnetic clutch 19
One end is connected to the control unit 1o, and the other end is connected to ground. Furthermore, the electromagnetic clutch 19 connects and disconnects the compressor and the drive source (engine), as is well known.

In the above configuration, the outside air temperature detection section 11 inputs the electric signal of the outside air temperature detection element 16 and outputs a signal converted into outside air temperature to the set temperature calculation section 12. Further, the evaporator outlet temperature detection section 13 inputs the electric signal of the evaporator temperature detection element 17 and outputs a signal converted into the evaporator outlet temperature to the determination section 14 . As shown in FIG. 4, the set temperature selector switch 18 is set to
It is equipped with a C mode operation section 18B. Either one of the set temperature selector switches 18 is pressed or both are not pressed, but both are not pressed.If the EC0NO mode operation part 18A is pressed, the terminal 1
8a and 18c are connected, and when A/C mode operation section 18B is pressed, terminals 18b and 18c are connected. The set temperature calculation unit 12 determines a set temperature based on the signal from the set temperature changeover switch 18 and the outside temperature signal, and outputs the determined temperature to the determination unit 14 .

The determination unit 14 compares the set temperature and the evaporator outlet temperature,
The determination result is output to the electromagnetic clutch drive section 16.

The electromagnetic clutch drive section 15 sends a signal for energizing or de-energizing the electromagnetic clutch 19 based on the determination result.

FIG. 6 is a flowchart of the control device.

First, it is determined which mode the set temperature changeover switch 18 is in. In this case, the terminal 12 of the set temperature calculation section 12
If a is connected to ground, EO:)N.

If the mode is YES and the terminal 12b is connected to ground, it is the A/C mode. Also, when neither is being operated, the compressor is stopped. When the A/C mode operation part 18B is pressed, the set temperature is constant regardless of the outside temperature, so if the evaporator outlet temperature T is set temperature T0, the compressor is stopped and the evaporator outlet temperature T> If the set temperature Tb, operate the compressor. If neither is the case, the previous state is maintained. If the EC0NO mode operation part 18A is pressed, the set temperature will change depending on the outside temperature.
First, the set temperature calculation section 12 determines the set temperature, and if the evaporator outlet temperature T is less than the set temperature Tc, the compressor is stopped, and conversely, if the evaporator outlet temperature T>the set temperature Ta, the compressor is activated.

If neither is the case, the previous state is maintained.

By performing the above control, even if the set temperature is set high, sufficient cooling capacity can be secured against changes in outside temperature, and the operating rate of the compressor can be kept to the lowest to achieve energy consumption efficiency. A vehicle air conditioning system with good performance can be realized.

Effects of the Invention As is clear from the above embodiments, the vehicle air conditioner according to the present invention sets the set temperature to an optimum value depending on the outside air temperature, so the operating rate of the compressor is reduced, and a sufficient energy saving effect can be obtained.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing the configuration of a wind circuit of a vehicle air conditioner equipped with an air mix structure showing a conventional example, Fig. 2 is a set temperature characteristic diagram of the same vehicle air conditioner, and Fig. 3 is a diagram of the present invention. A block circuit diagram of an air outlet temperature control device for a vehicle air conditioner according to an embodiment, FIG. 4 is an external view of a set temperature changeover switch in the air outlet temperature control device, and FIG. 6 is a diagram of control contents in the air outlet temperature control device. The flowchart diagram and FIG. 6 are set temperature characteristics diagrams of the same blowout temperature control device. 10...Control device, 11...Outside temperature detection section, 12...Set temperature calculation section, 13...
... Evaporator outlet temperature detection section, 14 ... Judgment section, 15 ... Electromagnetic clutch drive section, 16 ...
...Outside air temperature detection element, 17...Evaporator temperature detection element, 18...Temperature setting switch, 19
・・・・・・Electromagnetic clutch. Figure 2 Figure 5 Figure 6 Outside and back

Claims (1)

[Claims] an outside air temperature detection element that detects the temperature outside the vehicle; an evaporator temperature detection element that detects the temperature inside or at the outlet of the evaporator;
It is equipped with a set temperature changeover switch that changes the set temperature, a control device that determines and outputs the signals from both temperature detection elements and the set temperature changeover switch, and an electromagnetic clutch that operates the compressor intermittently based on the output signal of this control device. Further, the control device is provided with a set temperature calculation unit that calculates a set temperature based on the input of the set temperature changeover switch and the outside air temperature, and stops the compressor when the evaporator outlet temperature reaches the set temperature or less. Air outlet temperature control device for vehicle air conditioners.