JPS591153Y2 - Separate room temperature controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a room temperature control device, and more particularly to a room temperature control device that is provided with an indoor device and an outdoor device and is free from wiring errors between the devices.

In conventional room temperature control devices, such as coolers equipped with heat exchangers such as heat pumps, when the temperature is set in the indoor unit, a control signal is generated according to the set temperature, and this control signal turns the heat pump on and off. The room temperature is controlled to be maintained at a desired temperature.

The aforementioned control signal is a 0N AC signal from a commercial power source.
Since the signal is transmitted to the outdoor unit as 1 OFF, there are no restrictions on the cable connection to the outdoor unit, and therefore erroneous wiring hardly occurs.

However, recent room temperature control devices require high-level control such as the ability to control temperature more accurately and also to be able to link with program timers, etc., so the control circuit inside the indoor unit has become electronic. As time progressed, they began to be driven by DC power sources.

Setting the output signal to an AC (alternating current) signal in this DC converting circuit requires a converter, which increases costs.

On the other hand, if the output signal is a DC signal, the signal has directionality, so if the wiring is incorrect, there is a risk of damaging the power element in the output section.

Furthermore, since installation work for this type of room temperature control device is not necessarily performed by experienced personnel, the manufacturer must take sufficient measures to prevent wiring errors.

Therefore, the present invention aims to create a room temperature control device of this type that outputs a control signal from an indoor unit using a DC signal, and which is easy to handle by making it easy to detect incorrect wiring and not damaging the power element. The purpose is to provide.

Examples will be described below based on the drawings.

FIG. 1 is a block diagram of the embodiment, showing an indoor unit 1 and an outdoor unit 2.
Although they are separated by a considerable distance, they are connected by cables 3 and 4.

In the indoor unit 1, 5 is a control circuit which, when the room temperature is detected by the thermistor 6, responds to a set temperature given from a setting device (not shown) or a timer signal for time control.
Drives the power transistor 7 in the output section to turn it 0N1OFF
let

A diode 8 is connected in parallel to the power transistor 7, and its cathode and emitter are connected to the collector and the anode of the transistors 1 to 1, respectively, and are important for protecting the power transistor 7, as will be described later.

The collector of the power transistor 7 is connected to the terminals C and D of the outdoor unit 2 through the terminal A, and the emitter of the transistor 7 is connected to the terminals C and D of the outdoor unit 2 by cables 3 and 4, respectively, through the ground line and the terminal B.

The outdoor unit 2 includes a heat exchanger such as a heat pump, a compressor for the heat exchanger, a four-way valve, a fan, a fan motor, etc., but these are not shown and only the parts necessary for explaining the embodiment are shown. There is.

Reference numeral 9 denotes an AC power source, and a rectifier 10 includes a transformer, a full-wave rectifier, a capacitor, etc., and converts the AC into DC.

One of the output lines of the rectifier 10 is a ground line, which is connected to the cable 4 via a terminal and is connected to the indoor unit 1 in common with the ground.

The other output is a positive voltage line (2), which is connected to the collector of the power transistor 7 of the indoor unit via the DC relay 11 and terminal C, through the cable 3.

That is, the DC relay 11 connects the power transistor 7 to 0N.
In response to 1OFF, the power of the rectifier 10 causes 0N1
It is turned off.

12 is a surge killer diode connected in parallel to the DC relay 11.

With this configuration, when the transistor 7 is turned on, the DC relay 11 is energized, the normally open contact 13 of the DC relay 11 is closed, the compressor motor 14 is activated by AC power, and cooling or heating is performed.

Now, when constructing the equipment for such a separate room temperature controller, cable 3 is connected between terminals A and C, and cable 4 is connected between terminals B and C, as shown by the dotted line as 30.40 in Figure 1. If the wiring is incorrect, the current from the rectifier 10 will flow from the positive voltage line V - the DC relay 11 - the terminal C - the cable 4 (40) - the terminal B - the anode of the diode 8 - the diode 8 - the cathode terminal of the diode 8. A-cable 3 (
30) The current flows to the ground terminal of the single-terminal rectifier 10, and the DC relay 11 is energized.

Miswiring can be confirmed before the relay 11 is energized.

Furthermore, even if there is this incorrect wiring, power) transistor 1
Since the diode 8 is driven in the forward direction, the voltage between the collector and emitter of 0 is approximately 1 V due to its threshold characteristic, and the transistor 7 is not destroyed.

Next, referring to FIG. 2, this embodiment uses a large capacity light emitting diode 80 instead of the diode 8 in FIG. By embedding the power transistor 7 in the indoor unit 1, it is possible to prevent damage to the power transistor 7 due to incorrect wiring, and it is also convenient to detect incorrect wiring in the indoor unit 1.

Although the above-mentioned embodiments have been described with reference to an air-conditioning/heating unit, the present invention can be applied even if the unit is used exclusively for air-conditioning or heating.

As described above, in the present invention, since the outdoor equipment load is driven by the DC signal from the indoor equipment,
Not only does direct-to-alternate conversion eliminate the need for equipment, reducing costs, but diodes with cathodes and anodes connected to the collector and emitter of the power transistor on the output side of the indoor device are placed to prevent incorrect wiring. Even if there is, an excessive voltage will not be applied to the power I transistor, thus preventing damage to the power transistor.

Furthermore, even if the indoor device is not powered on and therefore the power transistor is in the OFF state, if the wiring is incorrect, the diode is driven in the forward direction, so the DC relay of the outdoor device is energized, and the DC relay of the outdoor device is energized. This makes it easy to discover incorrect wiring.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment, and FIG. 2 shows main parts of another embodiment. 1...Indoor unit, 2...Outdoor unit, 3, 4
...... Cable, 5... Control circuit, 6.
...Thermistor, 7...Transistor,
8... Diode, 10... Rectifier, 11... DC relay, 14... Compressor motor, 80... Light emitting diode.

Claims (1)

[Scope of utility model registration request] A separate room temperature control device that detects the room temperature in the indoor device to obtain a control signal, transmits this control signal to the outdoor device via a cable, and controls the equipment in the outdoor device to maintain the room temperature at a desired value. In this case, the output section of the indoor device includes a power transistor that performs a switching operation based on the control signal, and a forward current flowing in parallel with the collector-emitter of the power transistor and in the opposite direction to the current flowing between the collector-emitter. comprises a diode connected so that a current flows through the power transistor, and a pair of output terminals connected to the emitter and collector of the power transistor, respectively,
On the other hand, the input section of the outdoor device includes a rectifier, a DC relay that controls equipment in the outdoor device to which the DC voltage from the rectifier is applied, and the other end of the DC relay and the ground line of the rectifier. A separate room temperature control device comprising a pair of input terminals connected to each other, and the output terminal and the input terminal are connected via the cable.