JPS60112280A - Electric circuit for electric carpet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to electrical circuits for electric carpets.

If you place an electric kotatsu in a room with an electric carpet to keep warm, the carpet directly under the kotatsu will be heated to a level higher than the standard value, but the heat-sensitive wire of the carpet's temperature control device that is directly under the kotatsu is short and will not react. It is normal for the fuse to become sluggish and overheat, tripping the safety circuit and blowing the fuse. Cutting the fuse is extremely inconvenient and should be avoided. To solve this inconvenience, it has already been proposed to cut off the electricity to half of the electric carpet load by plugging in the kotatsu. In this case, the heating wire located in the damaged part of the carpet is selected as half of the load. This is based on the premise that in most cases the kotatsu is placed in the center. In this proposal, in order to heat the entire car head including half of the above load, the kotatsu would have to be unplugged, and if the kotatsu and carpet were used at the same time, the capacity would be exceeded and an excessive amount of current would flow. There was an inconvenience.

The present invention provides an electric circuit for an electric carpet that eliminates the above-mentioned disadvantages. A load capacity switching means is attached to the circuit, and the adjustment circuit is valved to operate the load capacity switching means only when the load on the service outlet exceeds a predetermined value. This eliminates the need to unplug the kotatsu each time the electric carpet is used to heat a room, and it is also possible to prevent excessive current from being generated by turning on both the electric carpet and the electric kotatsu.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an electric circuit for an electric carpet according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, the electric circuit of the electric carpet includes a power source 1, a control circuit 2, a safety circuit 3, a load circuit 4 provided with a load capacity switching means according to the present invention which will be described later, an adjustment circuit 5 provided according to the present invention, and It is equipped with a τ-screw outlet, for example, an outlet 6 exclusively for kotatsu. 7 is a main switch, 8 is a temperature fuse for the electric carpet load circuit, and 9 is a current fuse for the electric kotatsu. The control circuit 2 is equipped with a relay X1 that operates the disconnect switch 11 of the load circuit 4. The disconnection switch 11 is equipped with a contact 11b that communicates with the safety circuit and a contact 11a that communicates with the loads 13 and 14 via the changeover switch 12.A detection wire is installed around the loads 13 and 14, which are heating wires. 15 and 16 are wound.A two-wire heating device such as this, consisting of a heating wire and a sensing wire, is well known in the art, and therefore will not be explained in detail here.

The other ends of the loads 13 and 14 are respectively connected to the load capacity changeover switch 17, but in that case, the terminals of the load 13 are directly connected to the contacts 17a and 18 through the contacts 17b,
The terminals of the load 14 are directly coupled to a contact 17c and a contact 17d via a diode 19, respectively. Movable contacts 17e and 17f are provided opposite contacts 17a and 17b and contacts 17c and 17d. Movable contact 1
7e and 17f are connected to one terminal of the power supply.

The adjustment circuit 5 is connected to the service outlet l-6,! : It has a transformer 20 arranged in series, and the secondary side of this transformer is connected to the relay X2 through a valve 5CR21.

The load capacity changeover switch 17 of the load circuit is connected to this relay X2.
When relay X2 is not energized, movable contacts 17e and 17r are connected to contacts 17a and 1.7C, respectively, and when relay X2 is energized, movable contacts 17e and 17f are Contact points 17b, respectively.

17d.

When the main switch 7 is closed, the control circuit 2 is energized, and since the carpet is not heated at this time and is at room temperature, the control circuit 2 supplies a current to the relay XI. Due to the energization of relay X1, normally closed contact 11b opens and normally open contact 11
2 closes. The loads 13, 14 are thereby energized and the carpet is heated.

When the kotatsu-specific electrical outlet l-6 is not yet plugged in, or when the electrical outlet 6 is plugged in but the Kokso switch is not turned on, the relay x2 is not energized, and therefore the load switching capacity switch 17 can be connected to the contact 17a. The movable contact 17e and the contact 17C are joined to the movable contact 17f. When the carpeller 1- is heated to a predetermined temperature, the detection line 1
5 and 16, the control circuit interrupts power supply to relay XI, stops energizing relay X1, and contacts 11
a opens and contact 11b closes. Load 13 c! -14
energization is stopped, and heating of the car propellers 1 to 1 is interrupted. When the carpet cools down to a predetermined temperature or lower, the control circuit 2 supplies current to the relay X1 again, and this is repeated to maintain the carpet at the predetermined temperature within the range.

When the contact 11a of the disconnection switch 11 is welded closed and does not open even after heating the carpet to a predetermined temperature, the safety circuit 3 operates to cut off the temperature fuse 8.

When the load is applied to the kotatsu dedicated outlet 6, the adjustment circuit 5
0”) Voltage is applied to l-lance 20 and 5CR21
is turned on, energizing relay X2 and energizing it. The load capacity changeover switch 17 is activated by the energization of the relay X2, and the movable contact 'L7e is connected to the contact 12b, and the movable contact 17f is connected to the contact 17d. Thereby,
Loads 13 and 16 are connected via diodes 18 and 19, and half-wave energization is performed, and power consumption is reduced to 32 QW, which is half of 640 W.

In the embodiment shown in FIG. 2, a thyristor 21 is connected in series to each load 13, 14, and a series circuit of a resistor 22, a variable resistor 23, and a capacitor 24 is connected in parallel to these thyristors. ing. Furthermore, variable resistor 2
A relay contact 25 of relay X2 is connected in parallel to X2. 26 is a bidirectional switching element. The relay contact 25 is normally closed, so when the kotatsu is not switched on and the relay X2 is not energized, the capacitor 24 is charged under the short circuit of the variable resistor 23, and its charging time is short. The thyristor 21 is energized via the switching element 26 over almost all wavelengths and the carpet is heated at full load capacity. When the COXO switch is turned on, the relay contact 25 opens due to the energization of the relay X2, and the capacitor 2
4 is charged via the variable resistor 23, so the charging time becomes long. Accordingly, the energization time of the thyristor 21 is shortened accordingly, and the portion from the starting end of each half wavelength to the position corresponding to the charging time is missing, and each load capacity is reduced accordingly. By operating the variable resistor 23, the reduction in load capacity can be adjusted as desired. That is, the embodiment shown in FIG. 2 allows stepless adjustment of the load capacity.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of an electric circuit according to the present invention, and FIG. 2 shows a modification thereof. 4...Load circuit 5...Adjustment circuit 6...Service outlet 17...Load capacity changeover switch representative H'77-Σ(・-mi,-,-j

Claims (2)

[Claims] (1) An electric circuit for an electric carpet, characterized in that the load capacity switching means is activated by the adjustment circuit only when a service outlet or the outlet attached to the outlet is loaded with a load exceeding a predetermined value. . (2) The load capacity switching means includes means for steplessly adjusting the load capacity of the carpet load circuit when the load exceeds a predetermined value (service outlet). The electric circuit for an electric carpet according to item 1.