JPS62172116A - Heating device - Google Patents

Abstract

PURPOSE:To obtain a heating device which can provide comfortable heating, by providing a heater unit having higher and lower heating capacities, by feeding current to the heater of higher heating capacity at the starting time, and by switching it to that of lower heating capacity after a predetermined time has passed. CONSTITUTION:When a power source switch SW is turned on, a temperature detecting signal is compared with a temperature setting signal in a switching circuit 5. The level of a temperature detecting signal is lowered in accordance with the rise in room temperature, which is transmitted by the voltage produced between sensor electrodes S1, S2 and which is rectified and smoothed by a checking circuit 4. Feeding of current to a heater H1 or H2 is controlled and it works to keep a heater unit 2 at a predetermined temperature. The heater H1 of higher heating capacity is selected within a predetermined time after the starting time. When a predetermined counting time has passed, a counter circuit 8 outputs a high level signal. The signal is transmitted to the base of a transistor Q2 through a resistor R3, as well as to switch the contact point of a heater from higher heating capacity H1 to lower heating capacity H2. With such an arrangement, comfortability by an air conditioner is not spoiled even when a room temperature is low.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a heating device for an electric carpet or the like that has a plurality of heaters and controls the temperature by switching the heating capacity.

(Background technology) For heating devices such as electric carpets, heaters with high and low heat generation capacities are installed to quickly warm up when started, to prevent overheating during normal use, and to save energy. In addition, there are devices that allow you to select one of the heaters.

However, in conventional devices of this type, the heating capacity of the heater is switched (watt switching) by a manual switch, and it is difficult to automatically switch the heating capacity with a simple configuration. The realization of a heating system that can do this has been long awaited.

(Objective of the Invention) The present invention was proposed in view of the above points, and it heats up with a large amount of electric power at the time of starting, which requires a quick start-up, and then switches the heat generation capacity after a suitable time, thereby providing a comfortable The purpose of this invention is to provide a heating device that can perform various operations.

(Disclosure of the Invention) That is, in the present invention, heaters having high and low heat generation capacities are provided, and at the time of starting, the heater with the high heat generation capacity is energized, and the time from the time of starting is measured, and the The above objective is achieved by switching to a heater with a low heat generation capacity after a certain amount of time has elapsed.

Hereinafter, the present invention will be explained in detail with reference to the drawings showing examples.

FIG. 1 shows an embodiment corresponding to claim 1. In the figure, the commercial power source 1 is connected to the first heater H1 or the heating element 2 through the power switch SW and then through the contacts of the first relay Ry and the contacts of the second relay Ry. 1 and a second heater H2 are connected to form a closed circuit. Note that the first heater H is a heater with a high heat generating capacity, and the second heater H2 is a heater with a low heat generating capacity. Further, the primary winding of a power transformer T is connected to the commercial power supply 1 via a power switch, one end of the secondary winding of the power transformer T is connected to the control circuit ground, and the other end is connected to each DC power supply V in the circuit part. It is connected to the input terminal of the second power supply circuit 3 that supplies C.

On the other hand, the heating element 2 is arranged close to the sensor electrode S over almost the entire surface where the heaters H, , H, are arranged.

S, and these sensor electrodes S,, S,
.

A heat-sensitive material having a negative characteristic impedance with respect to the immediate temperature of the plastic semiconductor is provided between them. One of the sensor electrodes is supplied with an AC signal stepped down from the secondary winding of the power transformer T via a resistor R1, and the other sensor electrode S2 is connected to the control circuit ground. Ru.

Next, the voltage generated at the sensor electrodes S,, S2@ is input to the detection circuit 4, and this voltage is rectified and smoothed by the detection circuit 4, and a signal that changes depending on the temperature (temperature detection signal) and subsequent switching times #I
5 is entered. The switching circuit 5 compares the input temperature detection signal with the temperature setting signal and outputs a low level or high level signal, and the output of the switching circuit 5 drives the transistor Q and switches the relay Ry1. It's supposed to work.

On the other hand, the counting circuit 6 includes the oscillation port w57 and the counter circuit 8.
The output of the oscillation circuit 7 is given as an input to the counter circuit 8, and the count-up (full count) output terminal of the counter circuit 8 is connected to its own operation holding input terminal. , is designed to be connected to the base of the transistor Q that drives the relay Ry2.The normally closed contact NC of the relay fly2 is connected to the beak H, , (high heat generating capacity), and the normally open contact NO is connected to the heater. It is designed to be connected to H2 (low heat generation capacity).

When the power switch Svv is turned on, the voltage generated between the sensor electrodes is rectified and smoothed by the detection circuit 4, and a temperature detection signal that decreases as the temperature rises is generated. It is compared with the temperature setting signal of the switching circuit 5, and depending on the magnitude, the contact of the relay RV is turned on/off.
The heaters H, H2 are turned off, and the power supply to the heaters H, H2 is controlled to maintain the heating element 2 at a predetermined temperature. Note that within a predetermined period of time from the time of startup, the output of the counting circuit 6, which will be described later, is not generated, the relay Ry2 is not driven, and the heater H with a high heat generation capacity is selected as the heater. .

On the other hand, the counting circuit 6 starts counting by using the output signal of the oscillation port #17 as the clock input of the counter circuit 8 from the time of startup when the power switch SW is turned on, and when a predetermined counting time (for example, one hour) has elapsed. Counter circuit 8 is No.1
Outputs a level signal. This signal is connected to the base of transistor Q2 via resistor R3, and is also applied to its own operation holding input terminal in order to stop the counting operation and hold the current state. When the time has elapsed, transistor Q2 is turned on, operating relay Ry2, and switching the connection of the heater from H, f (high heat generating capacity) to H2 (low heat generating capacity).

Figure 2 shows the temperature change of the heating element 2 with respect to the elapsed time t.During the time t from the time of startup, high power heating is performed by the heater H1 with a high heat generating capacity, so the temperature rises quickly, and the temperature rises quickly at the time t0. After , the temperature change becomes gradual because the heater H2 with a low heat generation capacity performs low power heating.

FIG. 3 shows an example of the circuit of the counting port 5@6 in FIG.
The gate of T is connected to the clock input terminal of the counter circuit 8.

Next, FIG. 4 shows an embodiment corresponding to claim 2, in which the time from startup to switching of the heat generation capacity is changed according to the room temperature. It is. In other words, the lower the room temperature is, the slower the temperature rise after startup becomes and the heating by large electric power becomes insufficient. Since the configuration of the counting circuit 6 in the embodiment shown in FIGS. and 3 is only partially changed, only the counting circuit section will be explained.
The configuration is such that a parallel circuit of a negative characteristic thermistor NTC and a resistor R7 is connected in series with a resistor 1t6 between the gate of the programmable unijunction transistor PUT of the oscillation port #57 and the ground.

In operation, the resistance value of the negative characteristic thermistor NTC changes according to room temperature fluctuations, and when the chamber 1 crystal is low, the resistance value increases, so the gate voltage of the oscillation circuit 7 also increases, and the oscillation period (clock period) As a result, the time it takes for the counter circuit 8 to count up becomes longer, that is, the time from starting until the heat generating capacity is switched becomes longer. Further, when the room temperature is high, the resistance value of the negative characteristic thermistor NTC becomes small, the gate voltage of the oscillation circuit 7 becomes low, the oscillation cycle becomes short, and the time from start to switching of the heat generating capacity becomes short. That is, the cycle of the clock signal applied to the counter circuit 8 changes depending on the room temperature, and the time t0 required for switching from a heater with a high heat generation capacity to a heater with a low heat generation capacity after startup changes in response to the ambient temperature. Become.

5 and 6 show the temperature change of the heating element 2 with respect to the anode voltage vA, gate voltage 6, and elapsed time t of the programmable unijunction transistor PUT in the above embodiment, and FIG. case,
FIG. 6 shows a case where the room temperature is high. Therefore, when the room temperature is low, the energization time of the heater with a high heat generation capacity is t. On the contrary, when the room temperature is high, the energization time t0 can be shortened, so that high-power heating at the time of startup can be appropriately performed.

Next, FIG. 7 shows an embodiment corresponding to claim 3, and similarly to the embodiment shown in FIG. 4, the time from start to switching of heat generation capacity is It is designed to change depending on the room temperature. However, in this embodiment, instead of changing the oscillation cycle of the oscillation circuit, a switching signal related to temperature control of the heater is counted as an oscillation signal by the counter circuit 8. In other words, when the room temperature is low, the temperature of the heating element rises slowly, and when the room temperature is high, the temperature of the heating element rises quickly. Therefore, if the heat generation capacity is switched when this signal is counted a predetermined number of times, the time from startup until the heat generation capacity is switched can be changed depending on the room temperature. I can do it.

Figure 7 shows only the main parts, and relay R
The key point is that the signal output from the switching circuit 5 is used as the clock signal for the counter circuit 8 of the counting circuit 6 in order to control y.

In operation, the counter circuit 8 counts on/off signals of the switching circuit 5 related to temperature control from the time of startup, and sends out a signal when a predetermined number (for example, 8 times) has been counted. Therefore, Fig. 8 shows the temperature change of the heating element 2 with respect to the elapsed time t when the room temperature is low, and Fig. 9 shows the temperature change of the heating element 2 with respect to the elapsed time t when the room temperature is high. The time required to reach the desired temperature and turn on and off a predetermined number of times is longer than that required when the room temperature is high, and therefore the time t from the time of startup until the heat generating capacity is switched. can be changed like t0' and to' in response to changes in room temperature.

Next, FIG. 10 shows an embodiment corresponding to claim 4, and in this embodiment, in order to further accelerate the temperature rise at the time of starting, after a predetermined period of time has elapsed from starting, The set value of the temperature side is set high during a period in which high-power heating is performed until the heat generation capacity is switched.

Therefore, the configuration is such that the output signal of the counting circuit 6 is transmitted to the driving part of the relay Ry2, and is also applied to the inverting input terminal of the comparator CP, which is supplied with a pressure according to the set temperature of the switching circuit 5 via a resistor. I'm trying to connect. Further, the heater temperature setting signal set by the variable resistor VR is applied to the inverting input terminal of the comparator CP, and the heater temperature detection signal output from the detection circuit 4 is input to the non-inverting input terminal. It has become.

In operation, the output of the counting circuit 6 is the time t until the counter circuit 8 counts up. There is a four-level voltage during the period, and the voltage is maintained at a high level after counting up. Therefore, the inverting input terminal of the comparator CP is connected to the resistor R15 when the heat generating capacity is high at time t0 from the start and when the power is turned on overnight.
A low level voltage is applied through the heater, and the heater control temperature is set to a high level due to the low voltage. Furthermore, after the time t0 has elapsed since the start, the output of the counting circuit 6 becomes high level, and the output of the counting circuit 6 becomes higher than the resistor R05.
A high level signal is applied to the inverting input terminal of the comparator CP1 through the inverting input terminal of the comparator CP1, and the heater control vHJ>m degrees is set to be low. In other words, the heater altitude control set temperature is set high when the high heat generation capacity heater is energized until a predetermined time has elapsed from startup, and when the heater temperature control set temperature is switched to the low heat generation capacity heater after the predetermined time has elapsed. It will operate if it is set lower than that when using a high heat generation capacity heater.

FIG. 11 shows the temperature change of the heating element 2 over the elapsed time in the above example. Note that To is .

The set temperature for high heat generation capacity, T, is the setting for low heat generation capacity)
It is the crystallinity, and To>T.

(Effects of the Invention) As described above, in the present invention, in a heating device having a plurality of heaters and having different heat generating capacities by selectively switching these heaters, at the time of startup (higher heat generating capacity). The heater quickly raises the temperature, and after a predetermined period of time, automatically switches to the low heat generation capacity heater to prevent overheating, which has the effect of providing comfortable heating.

In addition, by changing the time for switching from a heater with a high heat generation capacity to a heater with a low heat generation capacity from the time of startup in response to the room temperature, it is possible to avoid compromising comfort when the room temperature is low.

Furthermore, by setting the control temperature when energizing the high heat generating capacity heater to be higher than the setting value when energizing the low heat generating 8-view heater, the temperature rise at startup can be made even faster.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram showing one embodiment of the heating device of the present invention, FIG. 2 is an explanatory diagram of its operation, FIG. 3 is an example of the configuration of the counting circuit in FIG. A circuit configuration diagram showing the main part of the embodiment, FIGS. 5 and 6 are operation explanatory diagrams, FIG. 7 is a circuit diagram showing the main part of another embodiment, and FIGS. An explanatory diagram of operation, Figure 1O is a circuit configuration diagram showing the main parts of another embodiment, and Figure 11 (explanatory diagram of other operation. 1... commercial power supply, 2... heating element, 3 ...Power supply circuit, 4...Detection circuit, 5...Switching circuit, 6...Counting circuit, 7...Oscillation circuit, 8...
... Counter circuit Semiei 14 Addition

Claims (4)

[Claims] (1) In a heating device that has a plurality of heaters and has at least two different heat generation capacities by selectively switching these heaters, the heat generation capacity at startup is large and the heat generation capacity after a predetermined period of time is increased. 1. A heating device comprising: means for switching to a small value; and a counting circuit that determines the predetermined time by counting oscillation signals. (2) The heating device according to claim 1, wherein the oscillation period of the oscillation signal is changed in correspondence with the room temperature, and the predetermined time from startup to switching of the heat generating capacity is made variable. (3) The heating device according to claim 1, wherein the predetermined time from startup to switching of the heat generating capacity is made variable by counting switching signals related to temperature control of the heater as oscillation signals. (4) The heating device according to claim 1, wherein the set temperature of the heater temperature control when the heat generating capacity is large is set higher than when the heat generating capacity is small.