JPH09243098A - Temperature control device for electric carpet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature control device for an electric carpet, wherein the device controls feeding of current based on a detected temperature of a single thermally sensitive wire and can prevent an overheating of a portion of a heater surface which is subject to a load. SOLUTION: A temperature control device for an electric carpet comprises an elapsed time measuring block 14 which measures a first elapsed time counted from starting of feeding of current to a heater which is initiated when a detected temperature falls to a lower limit temperature, a memory block 15 for storing a predetermined current feeding time which is set to be longer than a time necessary for elevating temperature from the lower limit to the upper limit at the time of feeding current under a condition that no load is on a heater surface, and a comparator block 16 which compares the first lapsed time with the predetermined current feeding time, wherein a temperature control circuit 7 stops feeding of current to the heater when the first elapsed time reaches the predetermined current feeding time.

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 for controlling the temperature of a heater surface of an electric carpet. More specifically, the present invention relates to a temperature control device for an electric carpet that controls the temperature of a portion of the heater surface that receives a load, and a temperature control device for an electric carpet that prevents an abnormal temperature rise.

[0002]

2. Description of the Related Art A conventional temperature control device for an electric carpet will be described with reference to FIGS. As shown in FIG. 7, a conventional temperature control device for an electric carpet is:
The electric carpet body 21 is provided with a heater wire 22 for heating the heater surface 21a, a sensor wire 23 for detecting the temperature of the heater surface 21a, and a controller 24 connected to the sensor wire 23.
The controller 24 constitutes a temperature control device 25.

The sensor wire 23 is attached along the heater wire 22 in parallel with the heater wire 22. The sensor wire 23 is formed by coating a heat-sensitive wire 26 whose impedance increases with an increase in temperature with an insulator such as polyvinyl chloride, and the heat-sensitive wire 26 is connected to the controller 24.

The controller 24, as shown in FIG.
Temperature control circuit 27, operation switch 28, relay contact 2
9, a relay drive circuit 30, a conversion unit 31, a temperature setting unit 32, and a temperature setting switch 33.

The relay contact 29 is provided on a power supply line that connects the heater wire 22 to the AC power source 34 via the operation switch 28, and starts or stops energization of the heater wire 22 by turning it on / off. Is. Further, the relay drive circuit 30 is connected to the temperature control circuit 27, and by the signal from the temperature control circuit 27 indicating the presence or absence of energization,
ON / OFF of the relay contact 29 is controlled.

The conversion unit 31 generates an input voltage V according to the impedance change of the heat sensitive wire 26, and the temperature control circuit 27.
Is entered. As a result, the heat-sensitive wire 26
The detected temperature T of is converted into an input voltage V which is a voltage signal and input to the temperature control circuit 27.

The temperature setting section 32 includes a temperature setting switch 33.
The set temperature T0 of the heater surface 21a inputted from the above is converted into the reference voltage V1 and the reference voltage V2 and sent to the temperature control circuit 27 as a signal. The reference voltage V1 and the reference voltage V2 are respectively the upper limit temperature T higher than the set temperature T0.
1 and the lower limit temperature T2 lower than the set temperature T0, and the difference (differential) between the upper limit temperature T1 and the lower limit temperature T2 is set to a small value so that the temperature change is not uncomfortable.

The temperature control circuit 27 is composed of a one-chip microcomputer, and the reference voltage V1 and the reference voltage V2 input from the temperature setting section 32 are stored therein. The temperature control circuit 27 detects the temperature of the sensor wire 23 from the change in the input voltage V, and controls energization to the heater wire 22 based on the comparison between the detected temperature T and the upper limit temperature T1 and the upper limit temperature T2. That is, when the input voltage V becomes equal to or lower than the reference voltage V2, the temperature control circuit 27 closes the relay contact 29 via the relay drive circuit 30 and starts energizing the heater wire 22. Conversely, when the input voltage V becomes equal to or higher than the reference voltage V1, the temperature control circuit 27 opens the relay contact 29 via the relay drive circuit 30, and the heater wire 22
Stop supplying power to

Next, the operation of the temperature control device 25 will be described. First, the operation switch 28 of the controller 24 is pressed, and the temperature setting switch 33 determines the set temperature T0 of the heater surface 21a. As a result, energization of the heater wire 22 is started. At the same time, the temperature setting unit 32 converts the set temperature T0 into the reference voltage V1 and the reference voltage V2, which is sent to the temperature control circuit 27 and stored therein.

When the heater wire 22 is energized, the heater wire 22
As the temperature rises, the impedance of the heat sensitive wire 26 rises and the input voltage V rises. When the input voltage V from the heat-sensitive wire 26 becomes equal to or higher than the reference voltage V1, the temperature control circuit 27 determines that the detected temperature T becomes equal to or higher than the upper limit temperature T1 set by the temperature setting switch 33. The power supply to the line 22 is stopped. This allows
The temperature of the heater wire 22 lowers the temperature of the heater surface 21a.

When the heater wire 22 is de-energized, the impedance of the heat sensitive wire 26 lowers as the temperature of the heater wire 22 drops, and the input voltage V drops. Then, when the input voltage V from the heat-sensitive wire 26 becomes equal to or lower than the reference voltage V2, the temperature control circuit 27 determines that the detected temperature T becomes equal to or lower than the lower limit temperature T2, so that energization to the heater wire 22 is started.
As a result, the temperature of the heater wire 22 rises, so that the temperature of the heater surface 21a rises. Then, such temperature control operation is repeated.

As described above, the conventional temperature control device 25 described above is used.
Then, the temperature control circuit 27 in the controller 24 controls the input voltage V and the reference voltage (the reference voltage V1 and the reference voltage V
The temperature of the heater surface 21a is controlled by comparing with 2).

According to the above construction, in the unloaded state in which nothing is placed on the heater surface 21a, the input voltage V from the heat sensitive wire 26 is kept substantially within the range from the reference voltage V2 to the reference voltage V1. Therefore, as shown in FIG. 9, the detected temperature T is substantially maintained within the range from the lower limit temperature T2 to the upper limit temperature T1. Then, when nothing is placed on the heater surface 21a, the time Δt1 ′ during which the heater wire 22 is continuously energized and the time Δt2 ′ during which the heater wire 22 is continuously deenergized are constant, Heater surface 21
The temperature of a is also controlled at a relatively stable temperature. In FIG. 9, the solid line shows the change in the detected temperature T when the heater wire 2 is energized, and the broken line shows the change in the detected temperature T when the heater wire 2 is not energized. ing.

[0014]

However, in the above-described conventional configuration, when a person rides on the heater surface 21a while the heater wire 22 is energized, the input voltage V from the heat sensitive wire 26 is The reference voltage V2 at which the energization of the heater wire 22 is started from the reference voltage V2 at which the energization of the heater wire 22 is started.
The time to rise to 1 is longer than Δt1 ′. The reason for the long time is as follows. That is, the heater surface 21
The temperature of the entire a is detected by using the single heat-sensitive wire 26, and the temperature of the heater surface 21a in the portion where the person is ridden by the person riding on the set temperature T0
It becomes hotter, and the temperature of the other parts where nothing is riding becomes lower than the set temperature T0. This is a phenomenon peculiar to the heat sensitive wire 26, and since the average temperature of the entire heater surface 21a is controlled, only the portion on which a person is riding becomes hotter than the set temperature T0.

The reason why the time required to increase from the reference voltage V2 at which the heater wire 22 is energized to the reference voltage V1 at which the heater wire 22 is stopped is longer than Δt1 'is as follows. To be That is, the load portion temperature of the portion on which the person is riding gradually rises beyond the set temperature T0, but the average temperature of the open portion temperature where the person is not riding continues to drop as the load portion temperature rises. The area of the heater surface 21a where the person is riding is about the same as the cushion, and the area of the open portion where the person is not riding is 5 to 1 times.
It is much wider than 0 times. Therefore, the time during which the heater wire 22 is energized is longer than the time during which the heater wire 22 is energized when nothing is on the heater surface 21a.

Further, in the above conventional structure, the heater surface 21
Even if the temperature of a is stable at the set temperature T0, it is set only when nothing is placed on the heater surface 21a (no-load state). That is, the actual temperature control of the electric carpet body 21 is performed by the heater surface 21a.
A specific portion of the heater is under load, for example, the heater surface 2
Since the operation is performed while a person is sitting on or lying on 1a, the temperature is significantly different from the set temperature T0 determined by the temperature control circuit 27 in the controller 24. Therefore, the heater surface 2
On 1a, the temperature of the part where the person is riding may not reach the set temperature T0.

That is, in the above structure, since the temperature of the entire heater surface 21a is detected by one heat-sensitive wire 26, due to the characteristics of the heat-sensitive wire 26, the portion of the heater surface 21a on which a person rides is not heated. Since the temperature is muffled, the temperature of that portion, that is, the sensible temperature becomes higher than the set temperature T0. On the other hand, since the other parts not occupied by a person are in a completely open state (no-load state), the temperature of that part is lower than that of the part where a person is riding.

Further, in the above configuration, since the temperature of the entire heater surface 21a is detected by one heat sensitive wire 26, another characteristic of the heat sensitive wire 26 is that the input voltage V from the heat sensitive wire 26 is It is an average value of the entire surface 21a. That is,
Since a high temperature portion and a low temperature portion are generated on the heater surface 21a, the temperature of the entire heater surface 21a is higher than the set temperature T0 when the temperature of the entire heater surface 21a is averaged, and the temperature of the portion where the person is not It is considered that the temperature becomes lower than the set temperature T0. Therefore, since the temperature of the portion on which the person is riding becomes higher than the set temperature T0, there is a drawback that the person feels hot.

Further, as shown in FIG. 10, when the electric carpet main body 21 is folded and electric current is mistakenly applied,
Since the heater surfaces 21b face each other and overlap each other, the input voltage V from the heat-sensitive wire 26 is changed from the reference voltage V2 at which the energization of the heater wire 22 is stopped to the heater wire 22 as compared with the case where nothing is mounted. The time required to fall to the reference voltage V1 at which the energization of the device is started is shorter than Δt2 '. As a result, since the heater wire 22 is energized for a long time, the temperature of the heater surfaces 21b overlapped with each other gradually rises to a considerably high temperature, resulting in a dangerous state.

Further, the surfaces of the heater surfaces 21b that are in contact with each other are in a sealed state without touching the air, and thus heat each other. Therefore, even if the temperature is controlled by the temperature control circuit 27, the temperature of the contact surface rises abnormally, which may cause a dangerous state.

The present invention prevents the temperature of the portion on which a person is riding from becoming higher than the set temperature, and when energized in the overlapping state, the temperature of the contact portion rises abnormally to a dangerous state. The purpose is to prevent becoming.

[0022]

In order to solve the above-mentioned problems, a temperature control device for an electric carpet according to a first aspect of the present invention controls the temperature of a heater surface of an electric carpet main body provided with a heater that generates heat by power supply. In order to control the temperature of the heater surface within a predetermined temperature range, in order to control the temperature of the heater surface within a predetermined temperature range, when the detected temperature rises to a predetermined upper limit temperature A temperature control unit that starts energization to the heater when the energization is stopped and the detected temperature drops to a predetermined lower limit temperature, and a first lapse from the time when the detected temperature drops to the lower limit temperature and energization to the heater starts. A first elapsed time measuring unit that measures time and a setting that is set longer than the time required to rise from the lower limit temperature to the upper limit temperature when the heater is energized with no load applied to the heater surface. A first storage unit for storing an energization time,
A first comparing the set energization time with the first elapsed time
A comparison unit is provided, and the temperature control unit controls the first elapsed time to be the set energization time based on the comparison result of the first comparison unit in order to suppress an abnormal increase in the temperature of the portion subjected to the load. It is characterized in that the energization of the heater is stopped when the temperature reaches.

According to the above configuration, the set energization time is based on the elapsed time when the actually measured temperature of the portion on which the person is riding reaches the upper limit temperature, and the input voltage of the heat-sensitive wire is set without load on the heater surface. Is set to be larger than the time required to rise from the lower limit value to the upper limit value, and is stored in the first storage unit in advance. That is, the set energization time is set on the basis of the elapsed time when the actually measured temperature of the portion on which the person is riding reaches the upper limit temperature. Therefore, the time for energizing the heater when nothing is on the heater surface is always shorter than the set energization time for energizing the heater when a person is on the heater surface. As a result, when nothing is placed on the heater surface, the value of the temperature detected by the heat-sensitive wire reaches the upper limit temperature at which energization to the heater is stopped before the first elapsed time reaches the set energization time. Control is performed regardless of the set energization time value.

On the other hand, when a person is on the heater surface, if the detected temperature does not reach the upper limit temperature after the set energization time has elapsed from the start of energization of the heater, the heater is forcibly forced. Stop energizing to. As a result, it is possible to suppress the temperature rise of the portion on which the person is riding, and to prevent the person from feeling hot and getting uncomfortable when riding.

In order to solve the above-mentioned problems, the temperature control device for an electric carpet according to a second aspect of the present invention controls the temperature of the heater surface of the electric carpet body provided with a heater that generates heat by power supply. In order to control the temperature of the heater surface within a predetermined temperature range with one heat-sensitive wire that detects the temperature of the heater surface, when the detected temperature rises to a predetermined upper limit temperature, energization of the heater is stopped. , A temperature controller that starts energizing the heater when the detected temperature drops to a predetermined lower limit temperature, and measures a second elapsed time from when the detected temperature rises to the upper limit temperature and the energization of the heater is stopped. The second elapsed time measuring unit and the time required for the temperature to drop from the upper limit temperature to the lower limit temperature when the heater changes from the energized state to the de-energized state with no load on the heater surface. A second storage unit that stores the set stop time that is set to a high level and a second comparison unit that compares the set stop time with the second elapsed time are provided, and the temperature control unit is overlaid with an electric carpet. In order to prevent an abnormal temperature rise in the above state, it is characterized in that energization to the heater is prohibited until the second elapsed time reaches the set stop time based on the comparison result of the second comparing section.

According to the above configuration, the set stop time for continuing to stop the energization of the heater is stored in advance in the second storage section. The set stop time is set to be shorter than the time required to decrease from the upper limit temperature to the lower limit temperature when the heater is energized with no load on the heater surface.

Therefore, the time during which the power supply to the heater is stopped when nothing is placed on the heater surface is longer than the set stop time during which the power supply to the heater is stopped while the heater surfaces are overlapped. It will always be long. As a result, when nothing is placed on the heater surface, the value of the temperature detected by the heat-sensitive wire reaches the lower limit temperature at which energization of the heater is stopped after the second elapsed time reaches the set stop time. Control is performed regardless of the set stop time value.

When the electric carpet is folded and the heater surfaces are overlapped with each other, the temperature detected by the heat-sensitive wire is equal to or lower than the voltage at which the heater is energized until the set stop time elapses after the heater is energized. However, the heater is not energized. Then, when the input voltage of the heat-sensitive wire is equal to or lower than the upper limit temperature at which the energization of the heater is started when the set stop time has elapsed, the heater is energized.

As a result, the heater is frequently energized.
It is possible to prevent -OFF and prevent an abnormal temperature rise on the surface where the heater surfaces of the electric carpet overlap when the electric carpet is erroneously energized.

Further, when the normal control is performed without folding, the temperature detected by the heat-sensitive wire does not become lower than the lower limit temperature at which the energization of the heater is started before the set stop time elapses. Absent. That is, when the temperature detected by the heat-sensitive wire becomes equal to or lower than the lower limit temperature for starting energization, the temperature control unit immediately detects and energizes the heater.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION

[Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 2, the temperature control device for an electric carpet includes a heater wire (heater) 2 for heating the heater surface 1a of the electric carpet body 1, and a sensor wire 3 for detecting the temperature of the heater surface 1a. A controller 4 connected to the heater wire 2 and the sensor wire 3 for controlling the temperature of the heater surface 1 a is provided, and the sensor wire 3 and the controller 4 constitute a temperature control device 5.

The sensor wire 3 is attached along the heater wire 2 in parallel with the heater wire 2. The sensor wire 3 is
The heat-sensitive wire 6 whose impedance increases as the temperature rises is covered with an insulator such as polyvinyl chloride, and the heat-sensitive wire 6 is connected to the controller 4. The sensor wire 3 may be integrated with the heater wire 2.

As shown in FIG. 1, the controller 4 includes a temperature control circuit (temperature control unit) 7, a power switch 8, a relay contact 9, a relay drive circuit 10, a conversion unit 11, a temperature setting unit 12, and a temperature setting switch 13. An elapsed time measuring unit 14, a storage unit (first storage unit) 15, and a comparison unit (first comparison unit) 16 are provided.

The relay contact 9 is provided on a power supply line that connects the heater wire 2 to the AC power source 17 via the operation switch 8, and starts or stops energization of the heater wire 2 by turning it on / off. Is. Further, the relay drive circuit 10 is connected to the temperature control circuit 7 and receives a signal from the temperature control circuit 7 indicating the presence or absence of energization.
ON / OFF is controlled.

The conversion unit 11 is adapted to generate an input voltage V according to a change in impedance of the heat-sensitive wire 6 and input it to the temperature control circuit 7. As a result, the detected temperature T of the heat-sensitive wire 6 is converted into the input voltage V which is a voltage signal and is input to the temperature control circuit 7.

The temperature setting section 12 includes a temperature setting switch 13
The set temperature T0 of the heater surface 1a input from the converter is converted into a reference voltage V1 and a reference voltage V2 and sent to the temperature control circuit 7 as a signal. Reference voltage V1 and reference voltage V
2 corresponds to an upper limit temperature T1 higher than the set temperature T0 and a lower limit temperature T2 lower than the set temperature T0, respectively,
The difference (differential) between the upper limit temperature T1 and the lower limit temperature T2 is set to a small value so that the temperature change is not uncomfortable.

The elapsed time measuring unit 14 measures the elapsed time (first elapsed time) t1 after the energization of the heater wire 2 is started by a clock or the like, and sequentially sends the obtained values to the comparing unit 16. It is like this.

A preset energization time Δt1 for continuing energization of the heater wire 2 is stored in the storage unit 15 in advance, and the value is sent to the comparison unit 16. Here, the set energization time Δt1 for continuing energization of the heater wire 2 is set to be longer than the time Δt1 ′ for energizing the heater wire 2 in a state where nothing is placed on the electric carpet 1.

The comparison unit 16 compares the elapsed time t1 sent from the elapsed time measuring unit 14 with the set energization time Δt1 stored in the storage unit 15. That is, the information on whether the elapsed time t1 is the set energization time Δt1 or more is sent to the temperature control circuit 7.

The temperature control circuit 7 has a reference voltage V1 and a reference voltage V2 preset by the temperature setting switch 13 stored therein. The temperature control circuit 7 compares the reference voltage V1 and the reference voltage V2 with the input voltage V and, based on the information sent from the comparison unit 16, starts or stops energization of the heater wire 2 at a timing described later. To do. That is, the temperature control circuit 7 closes the relay contact 9 via the relay drive circuit 10 at the timing when the energization of the heater wire 2 should be started. On the contrary, the temperature control circuit 7
Opens the relay contact 9 via the relay drive circuit 10 at the timing when the power supply to the heater wire 2 should be stopped.

Next, the temperature control device 5 for the electric carpet 1
Will be described. First, the operation switch 8 of the controller 4 is pressed to start energizing the heater wire 2. At the same time, by the temperature setting switch 13, the heater surface 1a
The set temperature T0 is determined, the set temperature T0 is converted by the temperature setting unit 12 into the reference voltage V1 and the reference voltage V2, sent to the temperature control circuit 7, and stored therein.

When the heater wire 2 is energized, the impedance of the heat sensitive wire 6 rises as the temperature of the heater wire 2 rises,
The input voltage V rises. Then, at a timing described later, the temperature control circuit 7 drives the relay drive circuit 10 to open the relay contact 9 and stop energizing the heater wire 2. As a result, the temperature of the heater wire 1 is lowered to lower the temperature of the heater surface 1a.

Here, referring to the flow chart shown in FIG. 3, after the detected temperature T drops to the lower limit temperature T2 and the energization of the heater wire 2 is started (hereinafter appropriately referred to as heater ON), temperature control is performed. The operation of the temperature control circuit 7 for controlling the timing at which the circuit 7 stops energizing the heater wire 2 (hereinafter, appropriately referred to as heater OFF) will be described.

First, as described above, the heater is turned on (S1). Next, the temperature control circuit 7 determines whether the input voltage V from the heat-sensitive wire 6 is the reference voltage V1 or higher, that is, whether the detected temperature T is the upper limit temperature T1 or higher (S).
2) If the detected temperature T is equal to or higher than the upper limit temperature T1,
The heater is turned off (S3).

On the other hand, when the detected temperature T is not higher than the upper limit temperature T1, based on the information sent from the comparison unit 16,
It is determined whether or not the elapsed time t1 from the heater ON has reached a preset set energization time Δt1 (S4). If the elapsed time t1 has not reached the set energization time Δt1, the process returns to S2 and again. Make a decision. On the other hand, the elapsed time t1
Has reached the set energization time Δt1, the heater O
FF is performed (S5).

As described above, the temperature control circuit 7 stops energizing the heater wire 2 when the detected temperature T becomes equal to or higher than the upper limit temperature T1 until the elapsed time t1 reaches the set energizing time Δt1. If the detected temperature T does not reach the upper limit temperature T1 even when t1 reaches the set energization time Δt1, the energization to the heater wire 2 is stopped at that time.

When the energization of the heater wire 2 is stopped as described above, the impedance of the heat sensitive wire 6 lowers as the temperature of the heater wire 2 drops, and the input voltage V drops. When the input voltage V from the heat-sensitive wire 6 becomes equal to or lower than the reference voltage V2, the temperature control circuit 7 determines that the detected temperature T becomes equal to or lower than the lower limit temperature T2, drives the relay drive circuit 10 and closes the relay contact 9. As a result, energization of the heater wire 2 is started. As a result, the temperature of the heater wire 2 is increased to raise the temperature of the heater surface 1a.

By repeating such temperature control operation, the temperature of the heater surface 1a is controlled.
As a result, when nothing is placed on the heater surface 1a, the detected temperature T reaches the upper limit temperature T1 until Δt1 elapses after the energization of the heater wire 2 is started, as in the period A shown in FIG. Reach Therefore, regardless of the value of the set energization time Δt1, the time when the detected temperature T reaches the upper limit temperature T1, that is, Δ
When t1 'has passed, the power supply to the heater wire 2 is stopped. In FIG. 4, a solid line shows a change in the detected temperature T when the heater wire 2 is energized, and a broken line shows a change in the detected temperature T when the heater wire 2 is not energized. ing.

On the other hand, when a person is on the heater surface 1a, the detected temperature T of the heat-sensitive wire 6 does not reach the upper limit temperature T1 as in the period B shown in FIG. Even if does not reach the upper limit temperature T1, the energization to the heater wire 2 is stopped when the set energization time Δt1 has elapsed from the start of the energization to the heater wire 2. This makes it possible to control the temperature of the heater surface 1a where the person is riding to a value closer to the set temperature T0, and to control the sensible temperature of the person who is riding to a more comfortable temperature.

[Second Embodiment] The following will describe another embodiment of the present invention in reference to FIG. 1, FIG. 5 and FIG. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

Elapsed time measuring unit (second elapsed time measuring unit) 1
4 measures the elapsed time (second elapsed time) t2 after the power supply to the heater wire 2 is stopped, and sends the obtained value to the comparison unit 16.

The storage section (second storage section) 15 stores in advance the set stop time Δt2 for continuing the energization of the heater wire 2, and sends the value to the comparison section 16. Here, as shown in FIG. 6, the set stop time Δt2 for continuing the energization of the heater wire 2 is the time Δt2 during which the energization of the heater wire 2 is stopped in a state where nothing is placed on the electric carpet 1. 'Is set longer than.

The comparing section (second comparing section) 16 compares the elapsed time t2 sent from the elapsed time measuring section 14 with the set stop time Δt2 stored in the storage section 15. That is, the information indicating whether the elapsed time t2 is equal to or longer than the set stop time Δt2 is sent to the temperature control circuit 7.

The temperature control circuit 7 stores therein the reference voltage V1 and the reference voltage V2 preset by the temperature setting switch 13. The temperature control circuit 7 compares the reference voltage V1 and the reference voltage V2 with the input voltage V and, based on the information sent from the comparison unit 16, starts or stops energization of the heater wire 2 at a timing described later. To do. That is, the temperature control circuit 7 closes the relay contact 9 via the relay drive circuit 10 at the timing when the energization of the heater wire 2 should be started. On the contrary, the temperature control circuit 7
Opens the relay contact 9 via the relay drive circuit 10 at the timing when the power supply to the heater wire 2 should be stopped.

Next, the temperature control device 5 for the electric carpet 1
Will be described. First, the operation switch 8 of the controller 4 is pressed to start energizing the heater wire 2. At the same time, by the temperature setting switch 13, the heater surface 1a
The set temperature T0 is determined, the set temperature T0 is converted by the temperature setting unit 12 into the reference voltage V1 and the reference voltage V2, sent to the temperature control circuit 7, and stored therein.

When the heater wire 2 is energized, the impedance of the heat sensitive wire 6 rises as the temperature of the heater wire 2 rises,
The input voltage V rises. Then, when the input voltage V from the heat-sensitive wire 6 becomes equal to or higher than the reference voltage V1, the temperature control circuit 7 determines that the detected temperature T becomes equal to or higher than the upper limit temperature T1 set by the temperature setting switch 13. Stop energizing line 2. That is, the temperature control circuit 7
However, the relay drive circuit 10 is driven to open the relay contact 9 to stop energizing the heater wire 2. As a result, the temperature of the heater wire 1 is lowered to lower the temperature of the heater surface 1a.

When the heater wire 2 is de-energized, the temperature of the heater wire 2 drops and the impedance of the heat sensitive wire 6 drops, so that the input voltage V drops. Then, the temperature control circuit 7 drives the relay drive circuit 10 at a timing described later to close the relay contact 9 to start energizing the heater wire 2.

Here, referring to the flow chart shown in FIG. 5, after the detected temperature T falls to the lower limit temperature T2 and the energization of the heater wire 2 is started (hereinafter, appropriately referred to as heater ON), temperature control is performed. The operation of the temperature control circuit 7 for controlling the timing at which the circuit 7 stops energizing the heater wire 2 (hereinafter, appropriately referred to as heater OFF) will be described.

First, as described above, the heater is off (S6). Next, the temperature control circuit 7 includes the comparison unit 16
It is determined whether the elapsed time t2 from the heater ON has reached a preset set stop time Δt2 based on the information sent from (S7), and the elapsed time t2 has not reached the set stop time Δt2. In this case, the determination is made again in S7.

On the other hand, when it is determined in S7 that the elapsed time t2 has reached the set stop time Δt2, the input voltage V from the heat sensitive wire 6 is the reference voltage V2 or less, that is, the detected temperature T is the lower limit temperature T2 or less. It is determined whether or not (S8), the detected temperature T
If it is determined that is not lower than the lower limit temperature T2, S8
Check again with. Then, the detected temperature T is the lower limit temperature T2.
If the following is determined, the heater is turned on (S9).

In this way, the temperature control circuit 7 does not energize the heater wire 2 until the elapsed time t2 reaches the set stop time Δt2 even if the detected temperature T drops to the lower limit temperature T2. If the detected temperature T is equal to or lower than the lower limit temperature T2 when the set stop time Δt2 is reached, the heater wire 2
Start energizing the. Elapsed time t2 is set stop time Δt
If the detected temperature T is not lower than or equal to the lower limit temperature T2 when the temperature reaches 2, then energization to the heater wire 2 is started at the time when the detected temperature T becomes equal to or lower than the lower limit temperature T2.

By starting the energization of the heater wire 2 as described above, the temperature of the heater wire 2 is increased to raise the temperature of the heater surface 1a.

By repeating such a temperature control operation, the temperature of the heater surface 1a is controlled. As a result, when nothing is placed on the heater surface 1a, as shown in FIG.
The detected temperature T does not become lower than or equal to the lower limit temperature T2 before the set stop time Δt2 elapses after the power supply to the heater wire 2 is stopped, as in the period A shown in FIG. Therefore, after the set stop time Δt2 has elapsed, the heater wire 2 is discharged when the detected temperature T becomes lower than or equal to the lower limit temperature T2, that is, when Δt2 ′ has elapsed.
Start energizing the. In FIG. 6, the solid line shows the change in the detected temperature T when the heater wire 2 is energized,
The broken line indicates the change in the detected temperature T when the power supply to the heater wire 2 is stopped.

On the other hand, when the heater surfaces 1a overlap each other, as in the period B shown in FIG. 6, from the start of energization of the heater wire 2 to the elapse of the set stop time Δt2, the heat sensitive wire 6 is exposed. Even when the detected temperature T becomes equal to or lower than the lower limit temperature T2, the power supply to the heater wire 2 is continuously stopped.

As described above, the set stop time Δt2 when the heater surfaces 1a are overlapped is set to a time shorter than the heater stop time Δt2 'when nothing is placed on the heater surface 1a, and the storage unit It is stored in 15. Heater surface 1a
In the state of overlapping, the heater wire 2 is not energized even when the detected temperature T of the heat-sensitive wire 6 reaches the heater energization start temperature, that is, the lower limit temperature T2, and the set stop time Δt2 from the deenergization of the heater wire 2 Until the time elapses, the energization of the heater wire 2 is continued, and the heater wire 2 is controlled so as not to be energized frequently. As a result, the heater surface 1a is overlapped with the heater wire 2
Even if the heater surface 1a is energized, the temperature rise of the overlapping heater surfaces 1a can be suppressed, and an abnormal temperature rise can be suppressed even if the heater surface 1a is energized for a long time.

[0066]

As described above, the temperature control device for an electric carpet according to the present invention is a temperature control device having a temperature control part for starting or stopping energization of a heater in accordance with a detected temperature. A first elapsed time measurement unit that measures the first elapsed time from when the temperature has dropped to the lower limit temperature and the energization of the heater has started, and the lower limit temperature when the heater is energized with no load on the heater surface. To a maximum temperature, a first storage unit that stores a set energization time that is set longer than the time required to rise to the upper limit temperature, and a first comparison unit that compares the set energization time with the first elapsed time are provided. The temperature control unit controls the heater when the first elapsed time reaches the set energization time, based on the comparison result of the first comparison unit, in order to suppress an abnormal increase in the temperature of the portion subjected to the load. Configuration to stop energization to A.

According to the above construction, the heater is stopped from being energized based on not only the detected temperature of the heat-sensitive wire but also the comparison of the set energizing time and the first elapsed time measuring section. It is possible to prevent the temperature from rising above the set temperature. As a result, there is an effect that comfort is obtained when a person gets on the vehicle.

As described above, the temperature control device for an electric carpet according to claim 2 is a temperature control device having a temperature control part for starting or stopping energization of the heater according to the detected temperature. Second time for measuring the second elapsed time from the time when the heater power is stopped due to the temperature rising to the upper limit
The elapsed time measuring unit and the set stop time set to be shorter than the time required to decrease from the upper limit temperature to the lower limit temperature when the heater changes from the energized state to the de-energized state with no load on the heater surface. The 2nd memory | storage part which memorize | stores and the 2nd comparison part which compares the said set stop time and the said 2nd elapsed time are provided, and the said temperature control part makes abnormal temperature rise in the state with which the electric carpet was piled up. In order to prevent this, energization to the heater is prohibited until the second elapsed time reaches the set stop time based on the comparison result of the second comparison unit.

According to the above construction, since the heater energization is started based on not only the detected temperature of the heat-sensitive wire but also the comparison between the set stop time and the second elapsed time, the heater is energized frequently. Can be suppressed. As a result, when the electric carpet is folded and the heater surfaces overlap,
It is possible to suppress an abnormal temperature rise. Moreover, since it has the function of the safety device, it is not necessary to provide another safety device, and the cost can be reduced.

As described above, the temperature control device for an electric carpet according to the present invention can perform appropriate control without changing various settings even when the load condition on the heater surface changes. It can be said that it is an epoch-making control device that can be done and has no factor of cost increase.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a temperature control device for an electric carpet according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a schematic configuration of the electric carpet.

FIG. 3 is a flowchart showing a control procedure in the temperature control device.

FIG. 4 is a graph showing changes in detected temperature in the temperature control device.

FIG. 5 is a flowchart showing a control procedure in the temperature control device for the electric carpet.

FIG. 6 is a graph showing another change in the detected temperature in the temperature control device.

FIG. 7 is a perspective view showing a schematic configuration of a conventional electric carpet.

FIG. 8 is a block diagram showing a schematic configuration of a conventional temperature control device for an electric carpet.

FIG. 9 is a graph showing changes in the detected temperature in the temperature control device.

FIG. 10 is a side view of the electric carpet in a folded state.

[Explanation of symbols]

1 Electric Carpet 1a Heater Surface 2 Heater Wire (Sensor) 3 Sensor Wire 4 Controller 5 Temperature Control Device 6 Heat Sensitive Wire 7 Temperature Control Circuit (Temperature Control Section) 14 Elapsed Time Measurement Section (First Elapsed Time Measurement Section, Second Section)
Elapsed time measuring unit) 15 storage unit (first storage unit, second storage unit) 16 comparison unit (first comparison unit, second comparison unit)

Claims (2)

[Claims] 1. A thermosensitive wire for detecting the temperature of the heater surface for controlling the temperature of the heater surface of an electric carpet main body having a heater that generates heat by power supply, and the temperature of the heater surface at a predetermined temperature. In order to control within the range, when the detected temperature rises to a predetermined upper limit temperature, energization to the heater is stopped, and when the detected temperature falls to a predetermined lower limit temperature, a temperature control unit that starts energization to the heater, The first elapsed time measurement unit that measures the first elapsed time from when the detected temperature drops to the lower limit temperature and the energization of the heater is started, and the lower limit when the heater is energized with no load on the heater surface. A first storage unit that stores a set energization time that is set longer than the time required to rise from the temperature to the upper limit temperature, and a first storage unit that compares the set energization time with the first elapsed time.
A comparison unit is provided, and the temperature control unit controls the first elapsed time to be the set energization time based on the comparison result of the first comparison unit in order to suppress an abnormal increase in the temperature of the portion subjected to the load. A temperature control device for an electric carpet, characterized in that power to the heater is stopped when the temperature reaches. 2. A heat-sensitive wire for detecting the temperature of the heater surface for controlling the temperature of the heater surface of an electric carpet body provided with a heater that generates heat by power supply, and the temperature of the heater surface is set to a predetermined temperature. In order to control within the range, when the detected temperature rises to a predetermined upper limit temperature, energization to the heater is stopped, and when the detected temperature falls to a predetermined lower limit temperature, a temperature control unit that starts energization to the heater, A second elapsed time measuring unit that measures the second elapsed time from when the detected temperature rises to the upper limit temperature and the current to the heater is stopped, and the heater is de-energized from the energized state with no load on the heater surface. A second storage unit that stores a set stop time that is set shorter than the time required to fall from the upper limit temperature to the lower limit temperature when the state changes, the set stop time, and the second elapsed time Second to compare with
And a comparison unit, and the temperature control unit sets the second elapsed time to the set stop time based on the comparison result of the second comparison unit in order to prevent an abnormal temperature rise in a state where the electric carpets are stacked. The temperature control device for the electric carpet is characterized in that the energization of the heater is prohibited until the temperature reaches.