JPS5860145A - Automatic changeover device for indoor and outdoor air - Google Patents

Abstract

PURPOSE:To automate changeover by forming a changeover mechanism so that the suction air is changed over to indoor air or outdoor air in response to temperature diffeence between indoor air and outdoor air and the operation of an air-cooling or heating device. CONSTITUTION:Outdoor temperature and indoor temperature are compared by means of a comparator 3 by signals from an outdoor temperature sensor 1 and an indoor temperature sensor 2, and the output and the output of a cooling and heatig discriminator 4 discriminating the state of air cooling or the state of air heating are inputted to a logical processing circuit 5. An actuator 8 is not driven when an automatic-manual changeover switch 6 is turned to the manual side, and the actuator 8 is driven by means of a control circuit 7 in response to the output of the logical processing cicuit 5 when the switch is turned to the automatic side. That is, suction air is changed over to outdoor air when the interior of a room is under the state of air cooling and outdoor temperature is lower than indoor temperature, and suction air is inversely changed over when the interior of the room is under the state of air heating.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that automatically switches between indoor air and outdoor air in a heating and cooling system.

Conventional internal/external air switching was either manual operation or fixed to the indoor air circulation 11 during 4IK cooling. For this reason, fixed types of indoor air circulation during cooling do not have a degree of freedom in selecting indoor and outdoor air, and manually operated types require human judgment and selection operations, resulting in poor efficiency. From the viewpoint of energy saving, it has been difficult to optimize these conventional types.

The present invention has been made in view of the above points.1.The purpose of the present invention is to generate air at a lower temperature depending on the cooling or heating depending on the difference between the negative outdoor temperature and the indoor air temperature. ,
Another object of the present invention is to provide an indoor/outdoor air automatic switching device that automatically selects air with a higher temperature in the case of heating, thereby solving the above-mentioned problems.

Hereinafter, the present invention will be explained by examples. Figure 1 shows the entire indoor/outdoor air automatic switching device in blocks.
The device includes two temperature sensors, an outdoor temperature sensor 1 and an indoor temperature sensor 2, and a comparator 3 that compares the outdoor temperature and the mold temperature using signals from the outdoor temperature sensor 1 and the indoor temperature sensor. A heating/cooling discriminator 4 that identifies whether it is a cooling state or a heating state, a logic processing circuit 5 that receives the output of the discriminator 4 and the output of the comparison 3 as input, and whether indoor/outdoor air switching is to be performed automatically or manually. When the switch 6 is on the manual side, the actuator is not driven, and when the switch 6 is on the automatic side, the logic processing circuit 5 is operated.
Control circuit 1 that drives the actuator 8 according to the output of
It is composed of

Figure 2 is a specific circuit diagram of the above device, in which the outdoor temperature sensor 1 and the indoor temperature sensor are temperature controlled by a thermistor.
One end of the outdoor temperature sensor 1 is connected to ground, the other end is connected to one end of the indoor temperature sensor 2, and both temperature sensors
The voltage at the common contact point U of step 1.2 becomes the comparator 30 input signal. The other end of the indoor temperature sensor 2 is connected to the power supply V+.

One end of fixed resistor 10 is connected to ground, the other end is connected to fixed resistor 1
The voltage at the common connection point of both constant resistors io and tt becomes the comparator 30 reference input signal. The other end of the fixed resistor 11 is connected to a power supply v0. The output signal of the comparator 3 becomes the input signal to the logic processing circuit 50.

In this example, the air conditioning/heating discriminator 4 uses a changeover switch, the movable contact of the air conditioning/heating discriminator 4 becomes the input terminal of the logic processing circuit 5, and the fixed contact is connected to the terminal for the cooling state and the ground for the heating state, respectively. Connected.

The logic processing circuit 5 is an exclusive logic circuit in this IFI, and the output signal of the circuit S becomes the input signal of the inverter 13 and the semiconductor switch 14, and the output signal of the inverter 13 becomes the input signal of the semiconductor switch 150.

The two semiconductor switches 14 and 15 each have a control terminal 1.
There are terminals 4a and ISm, and when a low level signal is applied to the terminals 14& and 151LK, the respective output terminals are opened, and conversely, when a high level signal is applied, each output signal is output at the same level as the input signal.

One end of the fixed resistor 12 is connected to ground, and the other end is connected to the control terminals 14 and 15 described above, and also connected to one end of the automatic/manual changeover switch 6.

The other end of the changeover switch 6 is connected to the power supply V+.

11Pli) Transistor 16 and PIP) Transistor I
T and T form a complementary transistor tm, each emitter is connected to the anode of the diode 21, the pace is connected to the output of the semiconductor switch 14, and the IK pace is connected to one end of the fixed resistor 24. The other end is connected to ground. The collector of NPN) transistor 16 is connected to the power supply V+, and the collector of PNP transistor 17 is connected to ground. The limit switch 20 is a position detection switch connected in parallel with the diode 21, and becomes oyy when the indoor/outdoor air switching valve is in the indoor air position.

NPH) transistor 18 and P11fP transistor 19
constitute a complementary transistor, each emitter is connected to the anode of the diode 23, the pace is connected to the output of the semiconductor switch 15, and the pace is connected to one end of a fixed resistor 25, and the other end of the resistor 25 is connected to the other end of the resistor 25. is connected to ground.

The collector of the NPN transistor 18 is connected to the power supply V+, and the collector of the PNP transistor 19 is connected to ground. The limit switch 22 is a position detection switch connected in parallel with the diode 23, and becomes oyy when the indoor/outdoor air switching valve is in the outdoor air position.

The actuator 8 is a motor in this example, and one end of the motor is connected to the connection point between the switch 20 and the cathode of the diode 210, and the other end is connected to the connection point between the switch 22 and the cathode of the diode 23. be done.

Next, the operation of the circuit shown in FIG. K11E2 will be explained. first,
It is assumed that the automatic-manual changeover switch 6 is on the manual side. In this case, the control terminal 14 of the two semiconductor switches 14, 15
Since a and F5a are each at a low level, the corresponding terminal 14'
, 15 outputs are each open.

Therefore, since the pace potentials of the four transistors 16, 17, 18 and 19 are connected to the ground via the fixed resistor 24 or 25, the current flows from peak to peak 8. do not have.

The case where the automatic/manual changeover switch 6 is on the automatic side will be described below. Assume that the indoor/outdoor air switching valve is in the indoor air position. Indoor temperature and outdoor temperature are selected.Here, R3 is the resistance value of the outdoor temperature sensor 1, and 1. is the resistance value of the indoor temperature sensor, Rt6 is the resistance value of the fixed resistor 10, and 1. R, , is the resistance value of the fixed resistor 11.

When the outdoor temperature is lower than the indoor temperature, the outdoor temperature sensor 1 and the indoor temperature sensor are used, and the output of the comparator 3 becomes a low level.

In the cooling state, the output signal of the cooling/heating M-discriminator 4 is at a high level, so one of the input signals of the logic processing ffi circuit 50 is at a low level and the other is at a high level, and the output signal of the circuit 5 is at a high level. becomes.

Follow? Therefore, the input signal of the semiconductor switch 140 becomes high level, and the output signal also becomes high level. semiconductor switch 15
Since the 0 input signal passes through the inverter 1s, it is at a low level, and the output signal is also at a low level.

Therefore, the 1iPN transistor 16 and the P) IP) transistor 10 are turned on, and the HPII) transistor 16° diode 21. Motor 8. The limit switch 22° and the P) IF) direction KIIE flow of the transistor 19 drives the motor 6, and the indoor/outdoor air g switching valve is switched from the indoor air to the outdoor air position. Then, the switch 20 becomes ON, and the switch 22 becomes 01ν,
The current is cut off, preventing the motor 8 from locking.

Next, the indoor temperature is lower than the outdoor temperature due to air conditioning.

Then, '1''><, and the output signal of the comparator 3 becomes a high level, and the output signal of the logic processing circuit 5 becomes a low level.Therefore, the output signal of the semiconductor switch 14 becomes a low level, and the output signal of the semiconductor switch 14 becomes a low level. The output signal of the switch 15 becomes a high level, and current flows in the direction of the PNP) transistor 1T and the NPN) transistor 1B, which are turned on. motor 8
is reversed, and the indoor/outdoor air switching valve is switched from the outside air position to the indoor air position. Then, the limit switch 2G becomes 01ν, and the switch 22 is turned on to cut off the current.

Above, we have explained the case during cooling, but regarding heating,
When the outdoor temperature is higher than the indoor temperature, the indoor/outdoor air switching valve is driven to the outdoor air position, and when the outdoor temperature is lower than the indoor temperature,
The indoor/outdoor air switching valve is driven to the indoor air position.

As explained above, according to the present invention, it is possible to automatically switch between indoor and outdoor air in the air conditioning system at the optimal time, thereby increasing the comfort of the user and improving the air conditioning. It has the characteristic of being able to reduce energy consumption. Therefore, it is suitable for automotive air conditioning systems and general air conditioning systems having an indoor/outdoor air switching mechanism.

[Brief Description of the Drawings] Fig. 1 is a block diagram of the indoor/outdoor air automatic switching device of the present invention;
FIG. 2 is a specific circuit diagram. 1...Outdoor temperature sensor, 2...Indoor temperature sensor, 3
...Comparator, 4...Heating/cooling discriminator, 5...Logic processing circuit, 6...Auto/manual changeover switch, 1...
Control circuit, 8...actuator. Figure 1 Figure 2 ζ

Claims (1)

[Claims] In a cooling device and/or heating device having a switching mechanism for switching intake air to indoor air or outdoor pressure, the temperature of the indoor air and the outdoor air is detected, and the temperature is determined according to the temperature difference and the operation of the cooling device or heating device. . An indoor/outdoor air automatic switching device, characterized in that the switching mechanism is pressurized to switch.