JPH03244929A - Electrical carpet - Google Patents

Abstract

PURPOSE:To prevent a surface temperature from being increased or decreased while a cover is not used by a method wherein the first set temperature adjusting means for increasing or decreasing a temperature set voltage Vset and the second set temperature adjusting means for decreasing or increasing the temperature set voltage Vset for a specified period of time from an output of a changing-over instruction of ON or OFF of a heater means with a control means are provided. CONSTITUTION:A heater member 1 is turned on, a temperature sensing voltage Vd of a main body 2 of a carpet reaches a temperature set voltage Vset, resulting in that an OFF changing-over instruction is outputted from a changing-over control means 6 in respect to the heater member 1 and then the heater member 1 is turned OFF. At this time, the temperature set voltage Vset is once decreased by the first set temperature control means 7 and after a specified period of time elapses, the set temperature voltage Vset is increased by the second set temperature control means 9. Accordingly, the heater member 1 is turned ON under a condition in which the main body 2 of the carpet is in a relative high temperature, and the surface temperature descends rapidly due to the fact that the carpet cover is not used and as the operation is delayed, even if an under-shooting along with this delay in operation is not so high, the surface temperature is sufficiently maintained.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to electric carpets.

(Prior Art) In a conventional electric carpet, as shown in FIG. 2, a temperature detection means 3 consisting of a sensor wire or the like is provided on a carpet body 2 on which a heating element 1 is laid, and an operation (not shown) is provided. Temperature setting means 4 consisting of a temperature adjustment volume or the like is provided in the section, and the temperature detection voltage Vd detected by the detection means 3 and the temperature setting voltage V set output from the setting means 4 are determined by the comparison means 5 at any time. The result of this comparison is sent to a switching control means 6 consisting of a microcomputer (hereinafter abbreviated as microcomputer), etc., and the heating element 1 is switched off so that the temperature of the carpet body 2 reaches almost the set temperature. It is designed to be controlled at a near constant temperature.

However, in this case, assuming that the temperature setting voltage V set is a constant value, when the heating element 1 Vd becomes lower than the temperature setting voltage V set during temperature control and the heating element 1 is turned on, the temperature setting voltage V set is increased. When the heating element 1 is turned off, the temperature setting voltage v set is lowered to make it difficult for the heating element 1 to turn on.
This prevents frequent on/off switching.

Incidentally, an electric carpet is used either by covering the carpet body 1 with a carpet cover or by removing the cover, but when the cover is not used, heat escapes more easily than when the cover is used.

Therefore, when the cover is not in use, the temperature increase detected by the temperature detecting means 3 due to the heat generating action of the heating element 1 is slower than when the cover is in use.

In other words, when the cover is not in use, the time from when the heating element 1 is turned on until it is turned off is longer than when the cover is used. Therefore, if a cushion or the like is placed on the carpet body 1 without a cover to keep it warm locally,
There was a risk that the local area would become abnormally hot, leading to burns or other accidents.

On the other hand, when the cover is not in use, the temperature drop curve detected by the temperature detecting means 3 due to the stoppage of the heat generating action of the heating element 1 is steeper than that when the cover is in use.

Therefore, even if the temperature detection voltage Vd decreases due to the stop of the heat generating action and reaches the temperature setting voltage V set, and the heating element 1 turns on, the undershoot due to the delay becomes large and it does not warm up easily, causing the carpet body 1 to become cold. I had a feeling.

Therefore, in order to eliminate such problems, it was necessary to devise measures such as making the surface fabric of the carpet body thicker so that it would be difficult for heat to escape even without a cover.

(Problems to be Solved by the Invention) As described above, in conventional electric carpets, in order to eliminate accidents such as burns and problems such as a drop in surface temperature when the cover is not used, it is necessary to thicken the surface fabric of the carpet body. It was necessary to devise a way to prevent heat from escaping even without a cover, which inevitably led to higher costs.

The present invention has been made based on these circumstances, and does not require any special measures to prevent heat from escaping, and can prevent localized surface temperature increases or significant decreases in surface temperature when the cover is not in use. The present invention aims to provide an electric carpet that can prevent such problems and reduce costs.

[Structure of the Invention (Means for Solving the Problems)] As shown in FIG. Temperature detection means 3 for detecting the temperature of 2
, a temperature setting means 4 that outputs the set temperature, a comparison means 5 that compares the temperature setting voltage V set by the setting means 4 and the temperature detection voltage Vd by the detection means 3, and based on the comparison result by the comparison means 5. a switching control means 6 for switching and controlling the heating element 1 to turn on and off, and increasing the temperature setting voltage v set of the setting means 4 in accordance with the output of an on-switching instruction or an off-switching instruction output of the heating element 1 by the control means 6; or a first set temperature adjusting means 7 for lowering the temperature, a time measuring means 8 for measuring a certain period of time from the output of an on-switching instruction or an off-switching instruction output of the heating element 1 by the control means 6, and a certain period of time being measured by this timing means 8. The second set temperature adjusting means 9 lowers or increases the temperature set voltage V set of the setting means 4 in response to the temperature change.

(Function) In the electric carpet having such a configuration, the heating element 1 is turned on in response to turning on the operation switch, and then the temperature detection voltage Vd of the carpet body 2 becomes the temperature setting voltage Vs.
When the temperature reaches et, an off switching instruction is output from the switching control means 6 to the heating element 1, and the heating element 1 is turned off. At this time, the temperature setting voltage V is set by the first setting temperature control means 7.
set is once lowered, and after a certain period of time has elapsed, the temperature set voltage V set is increased by the second set temperature control means 9.

Therefore, since the heating element 1 is turned on when the carpet body 2 is relatively high temperature, the surface temperature can be maintained even if the surface temperature suddenly drops because the carpet cover is not used and the undershoot due to the operation delay becomes large. Can be maintained sufficiently.

On the other hand, when the heating element 1 turns on, the temperature setting voltage V set is once increased by the first setting temperature control means 7.
After a certain period of time has elapsed, the second set temperature control means 9 lowers the temperature set voltage V set. Therefore, even if the temperature rises slowly because the carpet cover is not used, the heating element 1 is turned off in a relatively short time, so that abnormal high temperatures due to local heat retention are suppressed.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 3 is an electric circuit diagram of the electric carpet in this embodiment, and 10 in the figure is a microcomputer (hereinafter abbreviated as microcomputer) constituting the main body of the control section. This microcomputer 10 operates based on a preset program by supplying +5 volt power from a control power supply circuit 11, and operates through a temperature setting circuit 12, a differential circuit]3
, respectively control the relay drive circuit 14 and the LED lighting circuit 15. Further, a temperature signal comparison circuit 16, an initialization circuit 17, a clock generation circuit 18, and a switch input detection circuit 19 are each connected to the microcomputer 10.

In the figure, 20 is the heating surface mode: full surface, left side.

This is a carpet body with three modes on the right side.

A first heater 21 and a second heater 22 are wired to this carpet body 20, as well as a temperature sensor 23. 1st. The second heaters 21 and 22 each heat one side, and short circuit detection wires 24 and 25 are wound around each heater 21 and 22 through a temperature sensitive layer. The heaters 21 and 22 and the temperature sensor 23 are supplied with alternating current power from the control power supply circuit 11. Further, the output of the temperature sensor 23 is given to a temperature control circuit 26.

As shown in FIG. 4, the control power supply circuit 11 is configured to supply AC power VaC to each of the heaters 21, 22 and the temperature sensor 23 via an operation switch SWI and a temperature fuse TF. There is. Further, the AC power source VaC is also supplied to the LED lighting circuit 15.

Further, the control power supply circuit 11 connects the alternating current voltage to the diode D10. Half-wave rectification and smoothing with resistor R17 and capacitor C4, +12V with Zener diode ZDI
(Volts) of DC power, and a transistor of 15. Resistor R45, Zener diode ZD2. A stabilized DC power supply of +5■ is obtained by capacitor C8.

The +12V DC power supply is supplied to the temperature control circuit 26, the differential circuit 13, and the relay drive circuit 14, and the +5V DC stabilized power supply is supplied to the microcomputer 10, the temperature signal comparison circuit 16, the initialization circuit 17, and the switch. Supplied to one input circuit.

As shown in FIG. E] to E2 and a combined resistance of the low resistance 51 to obtain the temperature detection voltage Vs,
This voltage Vs is applied to the operational amplifier OP1. Resistance R26, resistance R
The voltage Vd corresponding to the temperature detected by the temperature sensor 23 is obtained across the capacitor C7 by rectifying and smoothing it by a peak hold circuit composed of a diode D11, a diode D11, and a capacitor C7.

As shown in FIG. 6, the temperature setting circuit 12 divides the half-wave power supply voltage VGB from the short circuit detection wire 25 wound around the second heater 22 with a resistor R49 and a resistor R24, and smoothes it with a capacitor C6. are doing.

Further, the half-wave power supply voltage VGA from the short circuit detection wire 24 wound around the first heater 21 is applied to the resistor R50 and the resistor R2.
5 to divide the voltage into transistor Q20 and transistor Q.
18 is turned on/off.

Here, transistor Q20 and transistor Q18
When on, resistor R35, thermistor TH and resistor R
32 combined resistances, temperature control volume VR, resistance R18
The voltage divided by the combined resistance of resistor R27 and transistor Q23. It becomes the set temperature voltage v set through the maximum temperature control circuit of resistor R30 and resistor R31. That is, this set temperature voltage V set is equal to the volume VR
It is possible to make changes corresponding to the carpet surface temperature set by. In addition, the thermistor TH detects changes in room temperature.
When the room temperature is low, the system corrects the temperature by raising it. Furthermore, when switching to single-sided operation, transistor Q19 is turned on and transistor Q20 is turned off, so that only transistor 01g is turned on/off, and resistor R28 is added to the voltage divider circuit to increase the set temperature voltage v se
The temperature is corrected so that the temperature is close to that of full-scale operation.

In addition, according to a command from the microcomputer 10, the transistor Q6 is turned on during the mite extermination operation, and the set temperature voltage V set is turned on.
The level is high regardless of the volume VR.

Further, during the rapid warming operation, the transistor Q8 is turned on to increase the set temperature voltage Vset. On the other hand, transistor Q
When the transistor 20 and the transistor 018 are on, the reference voltage is obtained as the sensor secondary foil disconnection detection voltage V cut.

As shown in FIG. 7, the temperature signal comparison circuit 16 receives the detected temperature voltage Vd from the temperature control circuit 26 at a non-inverting input terminal (+), and receives the set temperature voltage V from the temperature setting circuit 12. It has an operational amplifier OP2 that is input to the set or inverting input terminal (-). And [vd<vs
In the case of etl, the output of the operational amplifier OP2 becomes a low level, the transistor Q14 is turned off, and the temperature detection signal remains at a constant high level, so that [Vset < V d <
In the case of Vcut, the output of operational amplifier OP2 flips between high level and low level and is connected to transistor Q14.
turns on/off, the temperature detection signal repeats high level and low level, and [Vcut < V d ]
In this case, the output of the operational amplifier OP2 is at a low level, the transistor Q14 is turned on, and the temperature detection signal is configured to be at a constant low level. Here, the temperature detection signal is input to the microcomputer 10.

As shown in FIG. 8, in the differential circuit 13, when the differential signal from the microcomputer 10 becomes high level, a transistor Q17 is turned on, a transistor Q16 and a transistor Q7 are turned off, and the set temperature of the temperature setting circuit 12 is adjusted. When the voltage V set increases and the differential signal becomes low level, the transistor Q17 is turned off, the transistor Q16 and the transistor Q7 are turned on, and the set temperature voltage V set of the temperature setting circuit 12 is lowered. There is.

As shown in FIG. 9, the relay drive circuit 14 uses, as a relay coil power source, a DC power source obtained by half-wave rectifying and smoothing an AC power source using a diode DB, a resistor R4, and a capacitor C1. When the output from the microcomputer 10 is a relay ON signal, transistors Q4 and Q2 are turned on, thereby turning on relays RLA and RLB. Second heater 2
1.22 is energized, and in the case of a relay OFF signal, transistor Q4 and transistor Q2 are turned off, thereby turning off relay RLA and relay RLB,
1st. The second heaters 21 and 22 are configured to be de-energized.

Here, switching of the heating surface mode is performed by switch SW2 and switch SW3. That is, when switch SW2 is on, transistor Q1 is on, transistor Q2 is off, relay RLB is off, and the first
Only the heater 21 operates on one side. On the other hand, switch S
When WI is on, transistor Q3 is on, transistor Q4 is off, relay RLA is off, and the 21st
Only the heater 22 of A')- is operated on one side.

As shown in FIG. 10, the initialization circuit 17 keeps the output O at a low level until the supply voltage Vc to the power supply VDD of the microcomputer 10 reaches the microcomputer operating voltage.
The system includes a system reset IC (integrated circuit) 27 that sets the output O to a high level when the microcomputer operating voltage is reached.

The clock generation circuit 18, as shown in FIG.
For example, an oscillator Xi that generates a 455KHz internal clock
has.

As shown in FIG. 12, the switch input circuit detection circuit 19 includes a tick extermination switch SW5 and an instant warming switch SW6.
and an alarm switch SW7, each switch SW
When SW5 to SW7 are pressed, a high level signal is input to the microcomputer 10 as a switch input.

On the other hand, as shown in FIG. 12, the LED lighting circuit 15 reduces the voltage of the AC power supply Vac through a capacitor C3,
Half-wave rectification and voltage limit with Zener diode ZD3 and L
It is used as a power source for the ED circuit.

When a high level signal is output from the corresponding port of each LEDI~41 of the microcomputer 10, the corresponding transistor QIO~Q13 is turned on to light up the LEDI~4.

Furthermore, this electric carpet includes various safety circuits such as an overtemperature rise prevention circuit 28 shown in FIG. 13, a relay contact welding detection circuit 29 shown in FIG. 14, a short circuit detection line disconnection detection circuit 30 shown in FIG. A microcomputer failure detection circuit 31 shown in FIG. 16 is incorporated.

The microcomputer 10 receives power from the control power supply circuit 11 when the operation switch SWI is turned on, and initializes when this reaches the microcomputer operating voltage.

After initialization, the heating operation shown in FIG. 17 is started. That is, the temperature detection signal outputted from the temperature signal comparison circuit 16 is periodically captured, and the energization of each heater 21, 22 is controlled by controlling on/off of relay RLA and relay RLB according to this detection signal. . In other words, when the temperature detection signal is at a constant high level (
Vd<Vset) A relay OFF signal is output to the relay control circuit 14. Also, when the temperature detection signal is at a constant low level (Vd>Vcut), a relay OFF signal is output to the relay control circuit 14. On the other hand, when the temperature detection signal alternately changes between high level and low level (Vset < V d < V
cut), relay ON for relay control circuit 14
Output a signal.

Further, when the output to the relay control circuit 14 is switched from OFF to ON, the microcomputer 10 sets the differential signal to the differential circuit 13 at a high level, and at the same time starts timing by a built-in timer. When the built-in timer measures a predetermined period of time (for example, 3 minutes), the differential signal is returned to low level.

In the electric carpet having such a configuration, heating operation is started when the operation switch SW1 is turned on, and when the surface changeover switch SW2. Heaters 21 and 22 depending on the state of SW3
is energized. Further, the temperature setting voltage V set set by the temperature setting circuit 12 and the temperature detection voltage V (j detected by the temperature control circuit 26 are compared at any time by the temperature signal comparison circuit 16, and the temperature detection voltage Vd is the temperature setting voltage. When V set rises, the heaters 21 and 22 are turned off. As a result, the temperature detection voltage Vd
decreases, and when this temperature detection voltage Vd eventually reaches the temperature setting voltage v set, the relay control output turns the relay OFF.
The signal changes to a relay ON signal, and energization of the heaters 2 and 22 is restarted. At this time, the differential signal is switched from a low level to a high level, and the temperature setting voltage v set of the temperature setting circuit 12 increases in the direction of increasing the temperature, that is, in the direction of making it difficult for the relay to turn off.

At the same time, the microcontroller's built-in timer starts. and,
When this timer measures a certain period of time, the differential signal switches to low level and the temperature setting voltage V
set goes down.

In this way, the temperature setting voltage V is temporarily increased so that it becomes difficult for the relay to turn off when power is resumed to the heater.
Since the set is lowered after a certain period of time has elapsed, even if the temperature rises slowly because the carpet cover is unused, the energization to the heater is canceled in a relatively short time. Therefore, even if a cushion or the like is placed on the carpet body without a carpet cover to keep it warm locally, abnormal high temperatures due to this local heat retention are suppressed, and accidents such as burns are prevented. Therefore, it is not necessary to take measures such as increasing the thickness of the surface fabric of the carpet body, and costs can be reduced.

Note that the present invention is not limited to the above embodiments.

For example, in the embodiment described above, the temperature set voltage v set is lowered after a certain period of time has elapsed after being increased once the energization to the heater is resumed; The present invention also includes a system in which the relay is difficult to turn on, and after a certain period of time has elapsed, the set voltage v set is increased to restart energization to the heater at a relatively high temperature. By doing this, even if the carpet cover is unused and the temperature drop curve is steep and there is a large undershoot due to operation delay, the surface temperature can be maintained sufficiently. Therefore, it is no longer necessary to take measures such as thickening the surface fabric of the carpet body in consideration of the case where the carpet cover is not used, and it is possible to reduce costs.

It goes without saying that various other modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] As described in detail above, according to the present invention, there is no need for special measures to prevent heat from escaping, and local surface temperature increases and surface temperature decreases when the cover is not in use can be prevented. It is possible to provide an electric carpet that can prevent significant deterioration and reduce costs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a block diagram showing the conventional configuration, FIGS. 3 to 17 are diagrams showing an embodiment of the present invention, and FIG. Overall circuit configuration diagram, Figure 4 is a circuit diagram of the control power supply circuit, Figure 5 is a circuit diagram of the temperature control circuit, Figure 6 is a circuit diagram of the temperature setting circuit, and Figure 7 is a circuit diagram of the temperature control circuit.
Figure 8 is a circuit diagram of the temperature signal comparison circuit, Figure 8 is a circuit diagram of a differential circuit, Figure 9 is a circuit diagram of a relay drive circuit, Figure 10 is a circuit diagram of an initialization circuit, and Figure 11 is a circuit diagram of a clock generation circuit. Figures 12 and 12 are circuit diagrams of switch input detection and LED lighting circuits, and Figures 13 to 16.
17 is a circuit diagram of various safety circuits, and FIG. 17 is a flowchart showing heating operation processing of the microcomputer according to the present invention. 10...Microcomputer (microcomputer), 11...
・Control power supply circuit, 12...Temperature setting circuit, 13...
- Differential circuit, 14... Relay drive circuit, 16... Temperature signal comparison circuit, 20... Carpet body, 21.22... Heater (heating element) 23... Temperature sensor, 26... Temperature control circuit. Figure 1

Claims (1)

[Claims] A carpet body on which a heating element is laid, a temperature detection means for detecting the temperature of the carpet body heated by the heat generating action of the heating element, a temperature setting means for outputting a set temperature, and a temperature set by the setting means. a comparison means for comparing the temperature detected by the detection means; a switching control means for controlling switching on/off of the heating element based on the comparison result by the comparison means; and an instruction to turn on the heating element by the control means. A first unit that increases or decreases the set temperature of the setting means in accordance with the output or the off-switching instruction output.
a set temperature adjusting means; a time measuring means for measuring a predetermined time from the output of an on-switching instruction or an off-switching instruction output of the heating element by the control means; An electric carpet characterized by comprising second set temperature adjusting means for lowering or increasing the set temperature of the means.