JPS6343738Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a planar heating element such as an electric blanket or an electric carpet, and particularly to a planar heating element whose heat generating area can be changed.

For example, some electric blankets serve as both a bed blanket and a throw blanket. When used as a bed blanket, electricity is applied to only the bottom half of the total area, that is, only at the feet, to heat the entire area, and when used as a throw blanket, electricity is applied to the heater on the entire surface to heat the entire area. However, in conventional planar heating elements such as electric blankets, in order to change the heating area, the heater buried inside the blanket is divided into, for example, two blocks, and these divided heaters are connected to the power supply. Each heater was connected in parallel with a switch that supplied power to each heater, and turning both switches ON and OFF controlled the energization of the heaters to heat half or the entire surface. Therefore, 2 heaters
It's fine if it's only divided, but if you divide it into multiple units, that is, connect multiple heaters in parallel to the power supply to perform fine-grained heating, you will need multiple switches for each heater, and the switches will become larger. At the same time, the number of parts increased considerably, leading to an increase in the cost of the electric blanket.

The present invention has been developed in view of the above points, and is a planar heating element that can increase or decrease the heat generating area by simply switching the contacts of a switch, even if a large number of heaters are arranged, without complicating the configuration. It provides:

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a basic circuit diagram of an embodiment of the present invention.
In FIG. 1, 1 is a power source, and n heaters from heater _R1 to heater _Ro are connected in parallel to this power source 1. 2 is the heater R ₁ ~
It is a changeover switch for supplying power to each of the heaters R _o , and by connecting the switch 2 to each of the connection terminals S ₁ to S _o , the heater R ₁
~ Each of the heaters R _o is shorted. The heater R ₁ ~
Each of the heaters R _o is connected to a diode D ₁ for heater R ₁ and heater R ₂ , a diode D ₂ for _heater R ₂ and heater _{R 3 ,} and so on. They are short-circuited through diodes D ₁ to _{D o} provided between the connection terminal S ₁ and the connection terminal S _o . This respective diode D ₁ ~ diode
D _o are connected in the same direction, so for example, if switch 2 is connected to terminal S ₁ , power will be supplied to heater R ₁ only, and if switch 2 is connected to terminal S ₂ , power will be supplied to heater R ₂ and By sequentially connecting the switch 2 from the connecting terminal _S1 to the connecting terminal _S0 so that power is also supplied to the heater _R1 via the diode _D1 , the heater R1 to which power is supplied is connected from the heater _R1 to the heater _R0. It increases sequentially to . Therefore, the above heater
If R ₁ ~ heater R _o are arranged in a plane, switch 2
The heat generating area increases sequentially as the terminals are switched from terminal S ₁ to terminal S _o . In addition, 3 is a thyristor which is a unidirectional semiconductor element that conducts current to the heater R ₁ to heater R _o in only one direction, and 4 is a temperature control circuit provided near the heaters R ₁ to _{R o} . The heaters R ₁ to _{R o} are controlled by temperature control elements (not shown).
control the conduction of

Fig. 2 is a circuit example diagram when the present invention is applied to an electric blanket, and Fig. 3 is a perspective view of the electric blanket.
R ₁ and heater R ₂ are connected in parallel to power supply 1, and heater R ₂ is connected to heater R ₁ through a connection terminal.
Diode D ₁ provided between the connection point of S ₂ and heater R ₂ and the connection point of connection terminal S ₁ and heater R ₁
shorted by. Further, the heater R ₂ is arranged in a meandering manner on the upper half side, and the heater R ₁ is arranged on the lower half side. Note that 3 is a thyristor for temperature control. Therefore, by shorting the switch 2 to the terminal S ₂ side, power is supplied to the heater R 1 via the heater R ₂ and _the diode D ₁ , and the entire upper and lower surfaces are heated.
Can be used as a blanket. If the switch 2 is short-circuited to the terminal _S1 side, power is supplied only to the heater _R2 , and only the lower half of the heater R2 is heated, so that it can be used as a blanket to warm the feet. Therefore, just by switching switch 2 to terminal S ₁ and terminal S ₂ ,
Full or half switching can be performed without complicating the circuit configuration.

FIG. 4 is a circuit example diagram for ensuring safety when the temperature control thyristor 3 conducts in the opposite direction for some reason in the electric blanket shown in FIGS. 2 and 3. As shown in Figure 4,
A diode 4 having a polarity opposite to that of the thyristor 3 is connected in parallel, and a current fuse 5 is provided in series with the power supply. Therefore, according to this embodiment, even if the thyristor 3 conducts in the negative direction, the current immediately blows the current fuse 5 through the diode 4, thereby preventing the heater from overheating, etc., thereby ensuring safety. can.

Next, an embodiment in which a large number of heaters are connected in parallel will be described.

In FIG. 5, the electric blanket is divided into, for example, six blocks, and each block is provided with a heater. In FIG. 5, reference numeral 6 denotes a blanket, which is divided into six blocks in parallel from the bottom to the top, and heaters R ₁ to R ₆ are arranged in each block in a meandering manner. Each heater R ₁
~ _R6 is connected in parallel to power supply 1,
Switch 2 connected in series with contact S ₁ ~
Each heater R ₁ by connecting to each of S ₆
~Power is supplied to heater _R6 . Further, each of the heaters R ₁ to R ₆ is short-circuited by diodes D ₁ to D ₅ provided between the heaters and the contacts. Note that 3 is a thyristor, and 4 is a temperature control circuit. To explain the operation of the above configuration, for example, if switch 2 is connected to terminal S ₁ , heater R ₁
Only the bottom block is powered and generates heat, allowing you to warm only your toes. Furthermore, if switch 2 is connected to terminal S ₂ and terminal S ₃ in sequence,
Heater R ₁ , Heater R ₁ , R ₂ , Heater R ₁ , R ₂ , R ₃ ,
In this way, the heat generating area increases from the bottom to the top. In other words, the heat generating area can be increased or decreased simply by switching the contacts of the switch 2.

The above implementation was explained for the case where the heat generating area gradually increases from below, but if the blanket is used upside down, the heat generating area will increase from above to below, and if the blanket is used horizontally, the heat generating area will increase from the left or right side. do.
Furthermore, by changing the arrangement of the heaters, it is possible to increase the number of heaters outward from the center or from the outside inward.

Next, an embodiment in which the present invention is applied to an electric carpet will be described. In FIG. 6, 7 is an electric carpet, and the carpet 7 is divided into three blocks: a center part A, a middle part B surrounding the outer periphery of the center part A, and an outer peripheral part C surrounding the middle part B at the outermost periphery. Heaters R ₁ , R ₂ , and R ₃ are arranged in a meandering manner in blocks _A , B, and C _, respectively.
_R3 is connected in parallel to the power supply. Others are the same as the electric blanket, 2 is a switch, S ₁ ,
S ₂ and S ₃ are terminals, D ₁ and D ₂ are diodes, 3 is a thyristor, and 4 is a temperature control circuit. To explain the operation of the carpet, when the switch 2 is connected to the terminal S ₁ , the center part A (heater R ₁ ) generates heat, and the terminals S ₂ ,
As it connects to _S3 , the heat generating area gradually expands outward from the center, including the center A, middle B, and the entire surface. Therefore, if, for example, a yagura kotatsu is installed in the center area A, only the center area A of the carpet can be heated instead of the yagura kotatsu's heater, and the inside of the yagura can be used more widely by removing the yagura kotatsu's heater. If it is cold only in the central part A, connect switch 2 to terminal S ₂ and remove the sitting part, that is, the central part B.
It is also possible to use it to generate heat, or even to generate heat over the entire surface.

As described above, in the embodiment of the present invention, if the blanket or carpet is further divided into multiple parts, detailed heating can be performed, and even when the blanket or carpet is divided into multiple parts, the switch part that increases or decreases the heating area is connected to the terminals S ₁ to _{S o} and the switch 2. It is very compact since there is only one. Note that the switch 2 may be of any type, such as a rotary type or a sliding type.

As described above, according to the present invention, a changeover switch is provided to supply power to each heater connected in parallel, and a diode is provided to short-circuit each heater between the heater and the connection terminal of the changeover switch. Even if a large number of switches are connected in parallel, the heat generating area can be increased or decreased by connecting the switches to the terminals without complicating the configuration or increasing the size.
In other words, the heat generating area can be increased or decreased simply by switching the many contacts provided for one switch.
In addition, this switch is not only a switch for increasing/decreasing the heat generating area, but also a switch for increasing or decreasing the heat generating area.
It can also be used as an ON/OFF switch.

[Brief explanation of the drawing]

Figure 1 is a basic circuit diagram of an embodiment of the present invention, Figure 2 is a circuit diagram when the present invention is applied to an electric blanket, and Figure 3 is a basic circuit diagram of an embodiment of the present invention.
The figures are perspective views of the electric blanket, Figures 4, 5, and 6.
The figure is an explanatory diagram of another embodiment. 1: Power supply, 2: Switch, D: Diode,
S: Connection terminal, R: Heater.

Claims (1)

[Claims for Utility Model Registration] A planar heating element comprising at least two or more heaters connected in parallel to a power source disposed within a cloth body, with a changeover switch for supplying power to each heater, A planar heating device characterized in that a diode for connecting each heater is provided between the heater and a connection terminal of a changeover switch, and a unidirectional semiconductor element is provided that allows current to be supplied to the heater in only one direction. body.