JPS6044683B2 - temperature control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature control device used in heating and cooling equipment.

Conventionally, temperature control devices used in air conditioners, such as air conditioners, output an on signal when the temperature of the conditioned room reaches a first set value, and output an off signal when the temperature reaches a second set value. This was used to control on/off operation of the air conditioner.

Therefore, when the air conditioning load is large, the air conditioner may have to be operated for an extremely long time from around the second set value until reaching the second set value. This consumes a large amount of power or fuel to obtain a small temperature, which is not desirable from the viewpoint of effective energy utilization. The above will be further explained with reference to the drawings, taking the cooling operation as an example.

FIG. 1 is a temperature change diagram of an air conditioned room, where TA is the first set point temperature, that is, the operation start temperature of the air conditioner, and TB is the second set point temperature, that is, the operation stop temperature. Tc is the operating temperature range of the temperature control device, expressed as TO=TA-TB, and is usually about 3
It is set to °C. Sections 1 and 2 indicate the operation time and stop time of the air conditioner, respectively. As is clear from this figure, temperature changes are extremely gradual in section C, indicated by the dotted line, in the latter half of operation time A. This type of operation is often seen when the outside temperature is high during the day or when a large number of people are in the room to be cooled. Sometimes it takes up half of the time to run the air conditioner. This invention was made in view of the above points, and detects the rate of temperature change in the environment to be cooled and heated.
When this temperature change rate becomes smaller than a predetermined rate of change, the second set value or both the first and second set values are changed to stop the operation of the air conditioning equipment before the previous set temperature. It is something that makes you

The details of this invention will be explained below with reference to the drawings.

FIG. 2 is a block diagram showing an embodiment of the present invention, in which 1 is a temperature detection element, 2 is a temperature setting that sets a first set value for turning on the operation of the air conditioning equipment and a second set value for turning off the operation. Section 3 is a first comparator that compares the output from the temperature detection element 1 and the first set value from the temperature setting section 2, and outputs an on signal when the output of the temperature detection element 1 is larger; 4 also compares the output from the temperature detection element 1 and the second set value from the temperature setting section 2, and
A second comparator 5 which outputs an off signal when the output of
t is time), that is, an arithmetic circuit unit that calculates the rate of temperature change; 6 is a temperature change rate setting unit that sets a predetermined temperature change rate; 7 is the output of this temperature change rate setting unit 6 and the arithmetic circuit unit. This is a temperature change rate comparison section that compares the output of the arithmetic circuit section 5 with the output of the arithmetic circuit section 5 and generates an output when the output of the arithmetic circuit section 5 is smaller. Note that the arithmetic circuit section 5, the temperature change rate setting section 6, and the temperature change rate comparison section 7 constitute a set value changing section 8. Regarding the operation of an air conditioner configured in this way, when the room temperature is higher than the first set value temperature, the output of the temperature detection element 1 is higher than the first set value temperature. Since it is larger, the first comparator 3 outputs an on signal to operate the air conditioner (not shown).

When the room temperature becomes lower than the second set value temperature due to the operation of the air conditioner, the output of the temperature detection element 1 becomes smaller than the second set value, so the second comparator 4 outputs an off signal and the air conditioner is turned off. stop operating. Note that the first and second comparators 3 and 4
Once an on/off signal is generated, it continues to generate that output until an off or on signal is generated from the other comparators 4 and 3. In this way, the air conditioner normally operates on and off with the temperature difference Tc shown in Figure 1.However, the cooling load is large and the
When the characteristic shown in the dotted line in the figure is reached, the arithmetic circuit section 5 constantly changes the output change rate DT/D based on the output from the temperature detection element 1.
tl, that is, the temperature change rate is calculated, and the temperature change rate comparing section 7 compares this temperature change rate with a predetermined temperature change rate from the temperature change rate setting section 6, and when the indoor temperature change rate becomes smaller than the predetermined temperature change rate. , that is, the temperature T. At the point in time, the temperature change rate comparison section 7
generates an output, and this output causes the temperature setting section 2 to set the second
Since the setting value of is changed from TB to TD, the second comparator 4
An off signal is issued and the air conditioner stops operating. Next, a specific example of the configuration of the temperature detection element 1, temperature setting section 2, and first and second comparators 3 and 4 will be described with reference to FIG.

In this figure, 1 is an NTC thermistor as a temperature detection element.
9, 10, 11, 12, and 13 are resistors that constitute a bridge circuit with this NTC thermistor 1, and the first set value and the second set value of the resistor 10 are determined depending on whether or not both ends thereof are short-circuited. Similarly, the resistor 12 changes the second set value by short-circuiting both ends thereof, and this constitutes the temperature setting section 2.

14 is a differential amplifier that detects the balance of the bridge circuit and produces an LO output when the (+) side input is higher than the (-) side input by a predetermined level, and serves as the first and second comparators. It fulfills the following.

15 is provided at both ends of the resistor 10, and a differential amplifier 14
A switching circuit 16 is provided at both ends of the resistor 12, and is turned on by the output from the temperature change rate comparator 7 of the set value changing section 8, and short-circuits the resistor 12. , 17 is a relay coil that is driven by the Hi output of the differential amplifier 14 and stops driving by the LO output, 18 is an air conditioner, 19 is its power source, 20
is a relay contact that turns on and off the air conditioner 18, and is operated by the relay coil 17.

In a circuit configured in this way, when the room temperature is higher than the second set value temperature, the resistance value of the NTC thermistor 1 is small, so the (+) side input level of the differential amplifier 14 is low, and the output becomes Hi and the relay is activated. Coil 17 is driven and relay contact 2
0 is turned on and the air conditioner 18 is operated.

When the room temperature decreases due to the operation of the air conditioner 18, the resistance value of the NTC thermistor 1 increases, and the (+) of the differential amplifier 14 increases.
) side input level becomes high. Then, when the room temperature reaches the second set value temperature, the output of the differential amplifier 14 is reversed and becomes inverted, releasing the relay coil 17, turning off the relay contact 20, and stopping the operation of the air conditioner 18. The switching circuit 15 is turned on and the resistor 10 is short-circuited. This resistance 1
Due to the short circuit of 0, the (-) side input level of the differential amplifier 14 becomes high, and the value at which the output is inverted from LO to Hi changes from the second set value to another value, that is, the first set value. Air conditioner 1
8, the room temperature rises, but the operation of the air conditioner 18 is stopped as the (-) side input level of the differential amplifier 14 becomes higher, and when it reaches the first set value, the differential amplifier 14 stops operating. The output of 14 changes from low to high. This reversal of the differential amplifier 14 drives the relay coil 17 again, starts the operation of the air conditioner 18, turns off the switching circuit 15, and sets the reversal level of the differential amplifier 14 to the second set value. Change to On the other hand, when the indoor temperature change rate output from the arithmetic circuit section 5 becomes smaller than the predetermined temperature change rate from the temperature change rate setting section 6, an output is generated from the temperature change rate comparison section 7, and the switching circuit section 16 is turned on. Resistor 12 is shorted. Then, the (-) side input level of the differential amplifier 14 becomes higher and the second set value temperature becomes higher, so that the air conditioner is stopped earlier. In the above embodiment, only the second set value is changed, but it is also possible to change both the first and second set values.
Of course, the same effect can also be obtained by increasing the set value of the average room temperature. FIG. 4 shows another embodiment of the present invention, in which numerals 1 to 7 are similar to the embodiment of FIG.

21 is an intermediate temperature setting section that determines a third set value provided between the first set value and the second set value; 22 is a comparison between this third set value and the output of the temperature detection element 1; A third comparator 23 generates an output when the output of the temperature detection element 1 exceeds a third set value, and a third comparator 23 has an output for both the third comparator 22 and the temperature change rate comparator 7. The temperature setting section 2 is operated by the output of this AND gate to change the second set value or both the first and second set values.

Note that the set value changing unit 8 is connected to the intermediate temperature setting unit 21, the third
The circuit includes a comparator 22 and an AND gate 23. With this configuration, as shown in Fig. 5, the indoor temperature becomes lower than the third set value, and furthermore, the temperature change rate becomes smaller than the predetermined temperature change rate without reaching the second set value temperature. Since the set value will be changed when the load is large and the indoor temperature is around the first set value TD, the temperature change rate will be smaller than the predetermined temperature change rate, the set value will be changed immediately and cooling will start. The machine does not stop operating and does not cause discomfort to the occupants.

FIG. 6 shows still another embodiment, in which the arithmetic circuit section 5
A disconnection portion 24 is provided between the temperature detection element 1 and the temperature detection element 1, and is capable of turning on and off the connection therebetween.

According to this device, the setting value changing section 8 can be added or removed as necessary. Note that this separation part 2
4 may be provided between the temperature change rate comparing section 7 and the temperature setting section 2. As described above, the present invention is a temperature control device that turns on heating and cooling equipment with a first setting value and turns it off with a second setting value, and calculates the rate of temperature change of the object to be cooled and heated when the heating and cooling equipment is used. However, when this value becomes smaller than a predetermined temperature change rate, the second
By changing the setting value or the first and second setting values, it is possible to stop operation in areas where inefficient heating and cooling operations were performed without causing much deterioration of the heating and cooling environment, making it economical. The present invention provides a temperature control device that enables operation.

[Brief explanation of the drawing]

Fig. 1 is a diagram of cooling temperature changes in an air-conditioned room, Fig. 2 is a block diagram showing an embodiment of the present invention, Fig. 3 is an electrical circuit diagram showing a part of it in detail, and Fig. 4 is a diagram of the cooling temperature of the air-conditioned room. FIG. 5 is a diagram showing changes in cooling temperature of an air-conditioned room under different heating and cooling loads, and FIG. 6 is a diagram showing still another embodiment. The same reference numerals in the figures indicate the same or equivalent parts, 1 is the temperature detection element, 2 is the temperature setting section, 3 is the first comparator, and 4 is the second
a comparator, 5 is an arithmetic circuit section, 6 is a temperature change rate setting section, 7 is a comparator;
8 is a temperature change rate comparison section, 8 is a set value change section, 18 is an air conditioner, 21 is an intermediate temperature setting section, 22 is a third comparator, 23 is an AND gate, and 24 is a separation section.

Claims (1)

[Claims] 1. A temperature detection element that detects the temperature of a controlled object; when the detected temperature of this temperature detection element reaches a preset first setting value, an on signal is output, and the temperature reaches a second setting value. In a temperature control device that controls the temperature of a controlled object by outputting an off signal when the heat source device is turned on and off, the temperature change rate detected by the temperature detection element is calculated between the two set values, and Temperature control characterized by comprising a set value changing unit that changes the second set value or both the first and second set values when the rate of change becomes smaller than a predetermined temperature change rate. Device. 2 A third set value is provided between the two set values, and when the detected temperature exceeds this value and the temperature change rate is smaller than the predetermined temperature change rate, the second set value or both the first and second set values are set. 2. The temperature control device according to claim 1, wherein the set value changing section is configured to change the set value. 3. The temperature control device according to claim 1 or 2, wherein the set value changing section is configured by incorporating a disconnection section that disables the set value changing operation.