JP3295458B2 - Temperature control device for warmer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature control device having a preheating means for turning on a power supply to a heating device, and more particularly to a temperature control device for a heating device which prevents an excessive rise in temperature due to preheating. It is about.

[0002]

2. Description of the Related Art If an electric blanket takes a long time to reach a set temperature after turning on a power supply, there is a problem in that the user goes to bed before the bedding warms up, and that he / she falls asleep. For this reason, conventionally, a preheating means for increasing the set temperature and adjusting the temperature is provided, and when the preheating is selected at the time of turning on the power, the bedding can be heated at a temperature higher than the set temperature, and the temperature can be rapidly increased, and the cooled bedding can be cooled. 2. Description of the Related Art It has been conventionally practiced to sufficiently warm the bed to prevent the temperature of the bedding from being low at bedtime or from lowering the bedding temperature with a cold body. However, such manual preheating means has a problem in that if the user forgets to cancel the preheating and goes to bed, even if he / she feels good at first, he / she may sweat or wake up after falling asleep.

[0003] Therefore, for example, in the prior art described in Japanese Patent Application Laid-Open No. 2-62611, when power is applied to a bed heater, the temperature is automatically set to a high temperature regardless of the set temperature, If the first timer counter and the second timer counter are started and the temperature at the time when the second timer counter has timed out reaches a predetermined temperature, the strong preheating is terminated in the set time of the first timer counter, and the second timer counter If the temperature at the time of time-up does not reach the predetermined temperature, strong preheating is performed until the time of the first timer counter expires. Also,
Prior art described in JP-A-2-62612 is
The first timer counter counts the time until a predetermined temperature is reached, and determines the time during which the second timer counter keeps strong preheating based on the count result. In any of these prior arts, when the strong preheating is completed, the temperature is automatically adjusted according to the set temperature to prevent the temperature from rising too much.

[0004]

By the way, the prior art described in the above-mentioned gazette has a problem that even if a short-time power failure occurs during the use of the heater and the power supply is restarted while the temperature of the heater is still high. There is a problem that the strong preheating is repeated regardless of the set temperature. This problem is described in Japanese Patent Application Laid-Open No. 2-626.
Prior art described in Japanese Patent Publication No. 12 is described with reference to FIG. Note that the horizontal axis in FIG. 4 is the time axis, and the vertical axis indicates the temperature. The upper curve H indicates a change in the temperature of the heater itself, and the lower curve S indicates a change in the temperature detected by the temperature sensor.

First, the normal case will be described. When the power is turned on to the heater, the control temperature is set to the strong set temperature θ _K higher than the set temperature θ _E , and the sensor timer θ _S detected by the temperature sensor reaches the strong set temperature θ _K by the first timer. The counter counts. By the way, when the power is turned on T
₀₁ Heater temperature theta ₀₁ is low, the strength until the counted value tau ₁ is the case of greater than a predetermined time τ (τ _1> τ), the second timer counter operates, and ends the time setting tau ' Temperature control based on the set temperature θ _K is performed. When the temperature of the heater at the time of turning on the power is high and the count value τ ₁ of the first timer counter is shorter than the predetermined time τ (τ ₁ <τ), the set time τ ′ of the second timer counter is shortened. I do.
As described above, when the heater is cold, the preheating is sufficiently performed. When the heater is not so cold, the preheating can be shortened to prevent the heater temperature from excessively rising.

Therefore, during heating (time T _{1 in} FIG. 4),
If there is a power outage for a relatively short time ΔT, the heater temperature θ _H and the sensor temperature θ _S are hardly reduced, so that when the power is turned on again (time T ₀₂ ), the heater is set to the strong setting as described above. The temperature θ _K is set. However, since the heater temperature recovers rapidly, the count value τ reaching the strong set temperature θ _K
1 is shortened, the second timer counter count the number h tau 'is shortened in a while it will be Heater is warmed to a temperature higher than the set temperature theta _E. Therefore, when the user sleeps deeply without noticing the power failure, there is a serious drawback that the user is too hot and sweats or wakes up as in the case of the manual preheating.

[0007] A heating pad used as a medical device has the same problem as described above. That is, the time set in advance for the heating pad, for example, 30 minutes, is not enough, and the patient may turn on the power supply once turned off.
In such a case, in the preheating means described above, in the case of re-use, the temperature of the heating pad rises above the set temperature, giving rise to a burning sensation due to unnecessarily high heat in the affected part, causing a medically undesirable problem. It is a danger.

The present invention has been made to solve the above problems, and detects the temperature of the heater at the time of turning on the power, performs preheating temperature control when the heater is cold, and controls the preheating temperature when the heater is warm. It is an object of the present invention to provide a temperature control device for a heating tool in which only normal temperature control is performed and the temperature does not rise above a set value.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, a temperature control device for a heating device according to the present invention comprises: a main body having a heater and a temperature sensor; a temperature setting means; Temperature control means for controlling the energization of the heater so as to be provided, and a preheating means, the preheating means,
After the power supply is turned, the timer counter for counting the time until the temperature reaches the set temperature detected by the temperature sensor is provided, the timer - when the counted value of the counter that have exceeded a predetermined reference value , change to a higher than the set temperature preheating set temperature, releases the preheating when the detected temperature of the temperature sensor reaches the pre set temperature, the controlling the temperature back to the set temperature, also the counted value is the If the temperature is equal to or less than the reference value, the temperature is controlled based on the set temperature.

[0010] In the present invention, the heating device means an appliance for warming using an electric heater, and should be construed to include not only electric blankets and electric carpets but also medical appliances such as heating pads. is there. The reference value set in the timer counter is not particularly limited, and may be appropriately selected depending on the heat capacity of the heater, the heat capacity of the heater, and the like. Further, the setting of the preheating set temperature may be such that the set value itself is increased, or the temperature signal from the temperature sensor may be converted into a temperature signal lower than the actual one.

Further, a second timer counter is provided in the preheating means, and when the temperature detected by the temperature sensor reaches a preheating set temperature, the second timer counter is operated, and the count value of the second timer counter is set to a predetermined value. , The preheating can be canceled. The set value of the second timer counter is not particularly limited and may be a constant value, but may be set to increase or decrease according to the magnitude of the count value of the first timer counter.

When a second timer counter is provided,
For example, it is suitable for a heating device such as a heating pad, which would cause a practical problem if the temperature rise time is not set relatively short. On the other hand, it is suitable for a heating device such as an electric blanket or an electric carpet, which does not pose a practical problem even if the temperature rise time is relatively long.

[0013]

A timer counter is provided for counting the time from when the power is turned on until the set temperature is reached. If the count value of the timer counter is equal to or greater than a predetermined value, the set temperature is increased to a preheat set temperature higher than the set temperature. The preheating means to be changed acts to raise the temperature rapidly when the temperature of the heater body is low when the power is turned on, and to prevent the temperature from rising excessively when the temperature is high.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. The temperature control device for a heater according to the first embodiment shown in FIG. 1 is applied to an electric blanket, in which a heater 2 and a temperature sensor 3 are arranged in a main body 1. As the temperature sensor 3, a conventional temperature sensor wire in which electrode wires 3b and 3c are arranged via a heat-sensitive resin 3a whose impedance changes according to the temperature and which is linear is used.

The commercial AC power supply E includes a heating circuit in which the thyristor 5 of the temperature control circuit 4 and the heater 2 are connected in series;
A signal circuit in which the temperature sensor 3 and the temperature signal circuit 6 are connected in series and a DC power supply circuit 7 are connected in parallel. The temperature signal circuit 6 includes a resistor 6b and a capacitor 6c via a coupling capacitor 6a, and a temperature signal voltage is generated in the capacitor 6c by a half-wave current flowing through the diode 6d. The diode 6e is a heat-sensitive resin 3a.
For passing an alternating current through the coupling capacitor 6a
Through which the DC component is cut, and the heat-sensitive resin 3
This is for preventing polarization of a. The temperature signal output from the temperature signal circuit 6 is supplied to a preheating setting circuit 9 described below.

The comparator 10 has a temperature signal voltage supplied from the preheating setting circuit 8 and a temperature setting circuit 8 comprising a variable resistor.
Is compared with a set temperature voltage given by the microcomputer, and the difference is detected and given to a microcomputer (hereinafter referred to as a microcomputer) 11. The preheating setting circuit 9 includes resistors 9a and 9b and a transistor 9c connected in series, and the transistor 9c is controlled by the microcomputer 11. That is, when an ON signal is supplied from the microcomputer 11 to the base of the transistor 9c, the resistor 9b is short-circuited, the circuit resistance is reduced, and the temperature of the main body 1 is determined to be low.

In addition to the above, the microcomputer 11 is set with a control program for the drive circuit 12 of the thyristor 5, a timer counter, and a count reference value τ ₀₁ (for example, 20 minutes) of the timer counter. That is, the commercial AC power supply E
Is turned on and started by the power supply from the DC power supply circuit 7, the program of the microcomputer 11 is initialized first, the program of the timer counter is operated, the elapsed time since the initialization is counted, and the comparator 10 is initialized. Is supplied to the drive circuit 12 based on the signal from

In the preheating program, the count value τ until the microcomputer 11 outputs the first off signal of the thyristor 5 when the power is turned on, the sensor temperature θ _S reaches the set temperature θ _E, and
_{When 11} exceeds the count reference value τ ₀₁ (τ ₁₁ > τ ₀₁ ),
Microcomputer 11, irrespective of the set temperature theta _E, set the preheat set temperature theta _R to preheat setting circuit 9 (an ON signal of the transistor 9c), until a signal for turning off the thyristor 5 from the comparator 10 is outputted , i.e., the temperature detected by the temperature sensor 3, i.e. the sensor temperature theta _S is, until it exceeds the pre set temperature _{θ R (θ S> θ R} ), the thyristor 5 continues on. On the other hand, the count value τ ₁₁ until the microcomputer 11 outputs the first off signal of the thyristor 5 becomes the count reference value τ ₀₁
When (τ ₁₁ <τ ₀₁ ), the microcomputer 11 does not output the ON signal of the transistor 9c of the preheating setting circuit 9 and directly controls the temperature based on the set temperature θ _E.

Next, the operation of the preheating program is shown in FIG.
This will be described with reference to the temperature chart shown. In FIG. 2, the time
Interval T₀₁And the initial temperature θ₀₁Is at room temperature in a cold room,
When the commercial AC power supply E is turned on and the heater 2 is energized,
11 starts the timer counter and the comparator
From 10, the sensor temperature θ_SIs the set temperature θ_ELower (θ _S
<Θ_E), The thyristor 5 is turned on.
The signal is given to the drive circuit 12. Sensor temperature θ_SRises
Constant temperature θ_EIs reached (θ_S= Θ_E), First thyristor 5
When a signal for turning off the comparator is given from the comparator 10, the microcomputer
11 is the count value of the timer counter (when
Interval) τ₁₁The count reference value τ₀₁Τ₁₁> Τ₀₁so
If there is, the microcomputer 11 outputs an ON signal to the preheating setting circuit 9.
Power.

When an ON signal is given to the preheating setting circuit 9, the transistor 9c is turned on and the resistor 9b is short-circuited.
Since the voltage charged in the capacitor 6c of the temperature signal circuit 6 is lowered, the comparator 10 behaves similarly to set the set temperature theta _E higher preheat set temperature theta _R has changed.
Therefore, although the heater 2 is once turned off, the energization is immediately resumed, and the temperature of the main body 1 continues to rise. When the sensor temperature θ _S of the temperature sensor 3 reaches the preheating set temperature θ _R (θ _R = θ _S ), the temperature difference signal of the comparator 10 becomes zero, and the microcomputer 11 outputs an off signal to the transistor 9c. while, it cancels the operation of the preheating setting circuit 9, and later is performed normal temperature control based on the set temperature theta _E.

Next, during heating, a short time ΔT from time T _1.
If there is a power outage for a while, the heater temperature θ _H and sensor temperature θ _S
Once decreases, but increases again by re-energization (time = T ₀₂ ). Then, as the initial temperature θ ₀₂ at the time of re-energization is higher, the time required for the sensor temperature θ _S to reach the set temperature θ _E , that is, the count value τ ₁₂ of the first timer counter becomes smaller.
When the microcomputer 11 determines that the count value τ ₁₂ is equal to or smaller than the count reference value τ ₀₁ (τ ₁₂ <τ ₀₁ ), the preheating set temperature θ _R
Without setting of temperature control based on the set temperature theta _E.
Therefore, when the temperature of the main body 1 is high, the preheating setting is not performed, so that it is possible to prevent the bedding temperature from excessively increasing.

The temperature control device for a heater according to the second embodiment is applied to a heating pad. In the circuit diagram of FIG. 1, a second timer counter is set in addition to the above-described timer counter set in the microcomputer 11. The circuit configuration was the same as that of Example 1 except that was set. Accordingly, the circuit diagram is omitted, and the temperature chart shown in FIG.
Will be described.

In FIG. 3, when energization is started at a low initial temperature θ ₀₁ (time T ₀₁ ), the timer counter starts counting, and the count value τ ₁₁ when the sensor temperature θ _s reaches the set temperature θ _E is reduced. When the count reference value τ greater than _01, the microcomputer 11
Turns on the preheating setting circuit 9. And the sensor temperature θ
When _S reaches the preheat set temperature theta _R, the microcomputer 11 starts the counting of the second timer counter. Then, count value tau ₁₂ of the second timer counter, the microcomputer 11 to match the count reference value tau ₀₂ set in advance microcomputer 11 outputs a signal for turning off the preheating setting circuit 9, the control temperature is the temperature setting circuit The temperature returns to the temperature set at 8.

After the treatment time is over and the treatment timer turns off the main switch (time T ₀₁ ), the patient turns on the main switch after a short time ΔT has elapsed (time T ₀₂ ).
In this case, the initial temperature θ _{02 of the} pad is maintained at a high temperature. Accordingly, a first timer counter count value tau ₂₁ up to sensor temperature theta _S reaches the set temperature theta _E is smaller than the count reference value tau _01. Therefore, the microcomputer 11 continues the temperature control without turning on the preheating setting circuit 9. Therefore, in the heating pad of the second embodiment, when the temperature is raised from a cold state, the second timer counter is operated, and the preheating is continued during that time, so that the preheating time is shortened, and after the first treatment time has elapsed, When the switch is turned on, the temperature is controlled without preheating, so that it is possible to prevent a burning sensation due to an excessive rise in temperature.

[0025]

As described above, the heater temperature control device of the present invention does not perform the preheating operation when the power is turned on, and determines whether or not to perform rapid preheating when the main body temperature reaches the set temperature. In the case where the power is turned on again due to a short-time power outage while the heater is being used, the preheating operation can be omitted to prevent the temperature of the heater from becoming too high, and If the temperature of the heater is low when the power is turned on, the heater can be preheated quickly, so that it is easy to use and the effect of saving power is obtained. Therefore, it is possible to prevent the patient from using the heating pad from giving a burning sensation due to unnecessarily high heat and to prevent the temperature of the electric blanket from rising too high. Can be provided.

[Brief description of the drawings]

FIG. 1 is a circuit diagram illustrating an outline of a temperature control circuit of a heating device according to a first embodiment of the present invention.

FIG. 2 is a temperature chart for explaining a temperature control operation of the heater shown in FIG. 1;

FIG. 3 is a temperature chart for explaining a temperature control operation of a heater according to a second embodiment.

FIG. 4 is a temperature chart for explaining a problem of a temperature control operation of a heater according to a conventional example.

[Explanation of symbols]

1 body 2 heater 3 temperature sensor 4 temperature control circuit 5 thyristor 6 temperature signal circuit 8 temperature setting circuit 9 preheating setting circuit 10 comparator 10 microcomputer 11 microcomputer τ ₀₁ count reference value τ ₀₂ count reference value τ ₁₁ value count value τ ₁₂ meter Numerical value τ ₂₁ count value θ temperature θ _E set temperature θ _R preheat set temperature θ _S sensor temperature E Commercial AC power supply T time ΔT short time

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-168384 (JP, A) JP-A-1-109684 (JP, A) JP-A-63-181285 (JP, A) JP-A-2- 268308 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05B 3/00 F24D 13/02 F24C 3/04

Claims (2)

(57) [Claims] 1. A main body comprising a heater and a temperature sensor, a temperature setting means, a temperature control means for controlling energization of a heater so that the main body temperature becomes a set temperature, and a preheating means, wherein the preheating means is provided. from being powered on, the timer counter for counting the time until the temperature reaches the set temperature detected by the temperature sensor is provided, said timer - the counting value of the counter exceeds a predetermined reference value that the changes in higher than the set temperature preheating set temperature, releases the preheating when the detected temperature of the temperature sensor reaches the pre set temperature, controlling the temperature back to the set temperature, also,
Temperature control device for Todan instrument value the counting is to perform temperature control on the basis of certain Continuing the set temperature below the reference value. 2. A second timer is provided in the preheating means, and when a temperature detected by the temperature sensor reaches a preheating set temperature, a second timer counter is operated, and a count value of the second timer counter becomes a predetermined value. 2. The temperature control device for a warming tool according to claim 1, wherein the preheating is released when the temperature reaches the temperature.