JPH0785949A - Electric heater apparatus - Google Patents

Abstract

PURPOSE:To provide an electric heater apparatus having a plurality of heat emitting elements, with which temp. control takes place while the heat emitting times of different element are made the same approximately. CONSTITUTION:In the case temp. change is large, temp. sensing is made by a temp. sensing circuit 28 in conformity to signal by a sensor 12, and a relay control circuit 221 for Surface A is turned on for current to a heater H1 of Surface A until the target temp. is attained, whereafter this heater H1 and a heater H2 of Surface B are turned off for a while. When the temp. drops to the current level, a relay control circuit 222 for Surface B is turned on to actuate the heater H2. In the case the temp. change is small, the target temp. level can not be attained within the max. set time T for actuating current feed to the heater H1, so that the current feed to it is followed by current feed to the heater H2 of Surface B so that the two heaters H1, H2 work alternately, and they are kept off when the target temp. level is attained. When the temp. drops to the current level, they are again turned on for alternate operations.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric heating apparatus for controlling the temperature by making the heat generation time of each heating element substantially equal.

[0002]

2. Description of the Related Art By the way, an electric heating appliance is another electric appliance which consumes a large amount of power, such as an air conditioner,
Often used in combination with electric stoves, electric kotatsu, etc., at this time, the total power consumption of various electric appliances becomes too large, and the power consumption is limited by the contracted capacity of the commercial power supply and the capacity of the outlet. There are harms, as well as
Electric floorboards for standing work such as kitchens also use electric cookers with high power consumption, such as electric kettles, microwave ovens,
Since it is often used in combination with an electromagnetic induction heater or the like, the total power consumption of various electric appliances may become too large.

In this case, when the electric heating apparatus uses a plurality of heaters such as an electric carpet of a heating area selection type, if the heating area is reduced by energizing only some of the heaters, the power consumption is reduced. So the problem can be solved.

As a conventional electric heating appliance, for example, the structure described in Japanese Patent Laid-Open No. 62-190330 is known.

The electric heating apparatus disclosed in Japanese Patent Laid-Open No. 62-190330 has a plurality of heating elements, and when the heating elements are heated, the on-cycle time is divided according to the number of heating elements. However, as shown in FIG. 5, different heating elements are sequentially made to generate heat corresponding to the divided on-cycle times. Then, the temperature is detected by a temperature detecting element such as a thermistor, and the instantaneous value control is performed within each on-cycle time by the detected temperature.

That is, when there are two heating elements,
Assuming that each heating element is the A surface and the B surface, as shown in FIG. 5, the time for using the A surface and the time for using the B surface are preliminarily time-divided, and within each time-divided time. The corresponding heating element is energized when the temperature detected by the temperature detecting element is below a predetermined value, and is stopped when the temperature is above the predetermined value.

If, for example, the temperature changes up and down a lot within a set time, the heating element is repeatedly turned on and off a plurality of times within a predetermined time, as shown in FIG. If the heating element on the surface B is repeatedly turned on and off and then the heating element on the surface B is repeatedly turned on and off, or conversely, if the temperature change within a predetermined time is small, As shown in (f), side A and side B
The heating elements on the surface alternately keep the on state and the off state, for example, the heating elements on the A side are turned on, and then the heating elements on the B side are turned on, and the heating elements on the A side and the B side are turned on. The heating elements on the surface are alternately turned on, and thereafter, the heating elements on the surface A and the surface B are both controlled to remain off for a while.

[0008]

However, as shown in FIG.
As shown in (d), when the temperature change of the heating element and the on-cycle time coincide with each other, for example, the heating element on the A side continues to be in the off state and the heating element on the B side continues to be in the on state. However, there is a problem in that one of the heating elements is only in the ON state and the other is in the OFF state, and the use of the heating element is biased, which may cause inconvenience.

The present invention has been made in view of the above problems, and when it has a plurality of heating elements, it provides an electric heating apparatus capable of controlling the temperature by making the heating times of the heating elements substantially equal. To aim.

[0010]

The electric heating appliance of the present invention comprises a plurality of heating elements, temperature detecting means for detecting the temperature due to the heat generated by these heating elements, and the temperature detected by the temperature detecting means is a predetermined temperature. In the following cases, a control means is provided which sequentially heats a part of each of the plurality of heating elements and keeps each heating element one heating time within a predetermined time.

[0011]

According to the present invention, when the temperature detected by the temperature detecting means is lower than the predetermined temperature by the control means, a plurality of heating elements are sequentially heated to turn on only one heating element and the other heating element. By preventing the body from being in the OFF state only and keeping each heating element's heat generation time within a predetermined time, only one heating element is continuously in the ON state when the temperature change is small. This is prevented, and the heat generation time of each heat generating element of the plurality of heat generating elements is made substantially equal.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the electric heating apparatus of the present invention will be described below with reference to the electric carpet shown in the drawings.

First, the electric carpet is composed of a rectangular electric carpet body 11 as shown in FIG.
On both end faces of the electric carpet body 11 in the longitudinal direction, A
The surface 11a and the B surface 11b are formed, and the areas of the A surface 11a and the B surface 11b are formed to be substantially equal. Also,
The A surface 11a and the B surface 11b respectively house, for example, a 445 W heater A1 for the A surface and a heater H2 for the B surface, and a sensor 12 as heating elements.
A control box 13 is connected to the H1 and the heater H2 on the B side and the sensor 12, and the control box 13
Is connected to a commercial AC power supply E. Then, when the heater H1 on the A side and the heater H2 on the B side are simultaneously operated, the power consumption becomes 890 W, and when either the heater H1 on the A side or the heater H2 on the B side is used,
It consumes 5W.

Further, as shown in FIG. 1, a commercial AC power source E
In parallel, a series circuit of the A side relay control circuit 22 ₁ of the A side switch means 21 _{1 and} the A side relay contact 23 ₁ and the A side heater H1 and the B side of the switch means 21 ₂ B The B side relay contact 23 ₂ of the B side relay control circuit 22 ₂ and the series circuit of the B side heater H2 are connected.

Further, the commercial AC power source E is connected to a temperature control circuit 24 including a microcomputer having a timer function as a control means, and the temperature control circuit 24 is connected to the A side relay control circuits 22 ₁ and B. The surface relay control circuit 22 ₂ is connected. Also, the temperature control circuit
An energization selection switch 25 for energizing both the heater H1 on the A side and the heater H2 on the B side simultaneously or alternately energizing one of them is connected to 24. In addition, the temperature control circuit 24
A temperature setting circuit 26 for setting the respective temperatures of the heaters H1 and H2 on the A side and B side, and a temperature detecting means 27 are connected to the.

In the temperature detecting means 27, the sensor 12 of the negative characteristic thermistor is connected between the commercial AC power source E via the resistor R1, the resistor R2 and the resistor R3, and the electrode of the sensor 12 has a sensor temperature-voltage. A temperature detection circuit 28 for conversion is connected.

Next, the operation of the above embodiment will be described.

First, when the energization selection switch 25 is used to select either full-face energization, half-face energization, or alternate energization, and when energizing the entire face, two heaters H on the A and B sides are used.
When both 1 and H2 are operated and half-surface energized, two A-side and B-side heaters H1 and H2 are operated, and when alternately energized, two A-side and B-side heated Energize heaters H1 and H2 alternately.

Further, the temperature setting circuit 26 sets a desired temperature.

In the case of full-surface energization and half-surface energization, when the temperature detection circuit 28 detects that the temperature detected by the sensor 12 has risen to a predetermined temperature, the impedance of the sensor 12 has also dropped, and the voltage has dropped. , Corresponding A side relay control circuit 22 ₁ or B side relay control circuit 22 ₂
Is controlled to stop the heater H1 on the A side or the heater H2 on the B side. Also, if the temperature drops below a specified value, the sensor
When the temperature detection circuit 28 detects that the impedance of 12 also rises and the voltage has risen, it controls the corresponding A side relay control circuit 22 ₁ or B side relay control circuit 22 ₂ to turn the A side heater H 1 Alternatively, the heater H2 on the B side is energized.

Next, the alternating energization will be described with reference to the flow chart shown in FIG.

When alternately operating the first half of the electric carpet, first, the temperature control circuit 24 turns on the relay control circuit 22 ₁ on the A side and closes the relay contact 23 ₁ on the A side to close the relay contact 23 ₁ on the A side. The heater H1 is energized to generate heat (step 1).

Then, the temperature detection circuit 28 detects whether the temperature detected by the sensor 12 has risen to a target temperature which is a predetermined temperature, the impedance of the sensor 12 has also dropped, and the voltage has dropped to a predetermined value (step 2 ), If the target temperature is not reached, use the temperature control circuit 24 to relay the A-side relay control circuit.
It is determined whether 22 minutes or more, which is the maximum set time T, has passed since 22 ₁ was turned on (step 3), and if 3 minutes or more has not elapsed, the process waits in step 2.

When the temperature reaches the target temperature in step 2, and when it is determined in step 3 that 3 minutes or more has passed, the relay control circuit 22 ₁ on the A side is turned off and the temperature control circuit 24 is turned on. The timer is reset (step 4).

Next, the temperature detection circuit 28 detects whether the temperature detected by the sensor 12 has dropped to a predetermined temperature, that is, the energization temperature, and the impedance of the sensor 12 has also risen to raise the voltage to a predetermined value (step 5) If the temperature has not dropped to the energization temperature, in step 5, the heater H1 on the A side and the heater H2 on the B side are kept on standby, and when the energization temperature is reached, the temperature control circuit 24 sets the B Surface relay control circuit 22
₂ turned on, closes the relay contacts 23 and _second side B, energizes the heater H2 of the B side is exothermic, to reset the timer (step 6).

Then, the temperature detection circuit 28 detects whether the temperature detected by the sensor 12 has risen to a target temperature which is a predetermined temperature, the impedance of the sensor 12 has also dropped, and the voltage has dropped to a predetermined value (step 7). ), If the target temperature is not reached, use the temperature control circuit 24 to relay the B side relay control circuit.
22 ₂ to turn on the determines whether three minutes have elapsed from more than (Step 8), if not older than 3 minutes, it waits in step 7.

When the temperature reaches the target temperature in step 7, and when it is determined in step 8 that 3 minutes or more has elapsed, the relay control circuit 22 ₂ on the B side is turned off and the temperature control circuit 24 is turned on. The timer is reset (step 9).

Next, the temperature detection circuit 28 detects whether the temperature detected by the sensor 12 has dropped to a predetermined temperature, that is, the energization temperature, and the impedance of the sensor 12 has also risen to a predetermined value (step 10) If the temperature has not dropped to the energization temperature, in step 9 heaters H1 and B on the A side
When the heater H2 on the surface is on standby and the energization temperature is reached, the process returns to step 1, the temperature control circuit 24 turns on the relay control circuit 22 ₁ on the A surface, and the relay contact 23 ₁ on the A surface is closed. Then, the heater H1 on the surface A is energized to generate heat.

If the temperature change is large when the above operation is performed, as shown in FIG. 4A, after the heater A of the A side is energized until the target temperature is reached, the heater of the A side is held for a while. H1 and the heater H2 on the B side are kept off, and when the energization temperature is reached, the heater H2 on the B side is turned on.

Further, when the temperature change is small, as shown in FIG.
As shown in (b) and FIG. 4 (c), the heater H1 on the A side is
Since the target temperature is not reached within the maximum set time T during which the power is turned on, the heater for side A is turned on after the heater H1 for side A is turned on.
H2 is energized, and thus the heater H1 on the A side and the heater H2 on the B side are alternately energized to reach the target temperature.
The heater H1 on the A side and the heater H2 on the B side are kept in the OFF state until the temperature falls to the energization temperature.

The heater H1 on the A side and the heater H on the B side are set not only by alternately energizing the heater H1 on the A side and the heater H2 on the B side by setting the maximum set time T once. It is possible to prevent one of H2 from being energized for a long time and generating heat on only one side. In particular, when the electric carpet is cold, it is possible to prevent only one of them from generating heat for a long time, and the heaters H1 on the A side and the heaters H2 on the B side can be energized substantially evenly.

In the above embodiment, one sensor 12 is provided for the heater H1 on the A side and the heater H2 on the B side, but it is provided corresponding to the heater H1 on the A side and the heater H2 on the B side, respectively. May be.

Further, the relay contacts 23 ₁ , on the A and B sides,
Instead of the 23 _2, it may be used a semiconductor power control element such as a triac.

Further, the heaters H1 on the A side and the heaters H2 on the B side are alternately energized once, but if the number of times on each side is the same, even if energized twice or three times or more. Good.

Although the maximum set time T is set to 3 minutes, it may be changed according to the target temperature or may be set to an arbitrary time.

According to the above embodiment, the heaters on the A side are alternately arranged.
By energizing the heater H1 and the heater H2 on the B side, the power consumption can be reduced and the load on the breaker can be reduced, so that a plurality of heating appliances can be used at the same time.

Further, the temperature control circuit 24 uses the heater H1 for the A side.
Since the heater H2 on the B side and the heater H2 on the B side are alternately energized and the maximum set time T is set, the control can be easily performed.

Furthermore, the number of heating elements is not limited to two, and three or more heating elements may be provided.

[0039]

According to the electric heating appliance of the present invention, when a temperature detected by the temperature detecting means is lower than a predetermined temperature, a plurality of heating elements are sequentially heated so that only a certain heating element is turned on. By preventing the other heating elements from being turned off only and setting each heating element to generate heat for one time within a predetermined time, only one heating element is continuous when the temperature change is small. Therefore, the heat generation time of each heating element of the plurality of heating elements can be made substantially equal.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an electric carpet of an embodiment of an electric heating appliance of the present invention.

FIG. 2 is a plan view showing the appearance of the electric carpet of the above.

FIG. 3 is a flowchart showing the same operation.

FIG. 4 is a timing chart showing the relationship between the on / off state and the voltage of the heater H1 on the A side and the heater H2 on the B side showing the same operation.

FIG. 5 is a timing chart showing the relationship between the on / off state of the heater on the A side and the heater on the B side and the voltage, showing the operation of the conventional example.

[Explanation of symbols]

 24 Temperature control circuit as control means 27 Temperature detection means H1, H2 Heater as heating element

Claims (1)

[Claims] 1. A plurality of heating elements, a temperature detecting means for detecting a temperature due to heat generation of the heating elements, and one of the plurality of heating elements when the temperature detected by the temperature detecting means is below a predetermined temperature. An electric heating appliance, comprising: a control unit that sequentially heats each unit and keeps each heating element to generate heat once within a predetermined time.