JPS6114150Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electric blanket that has a foot heater and a chest heater, and allows comfortable heating by freely varying the ratio of heat generation from the foot heater to the heat generation from the chest heater.

Generally, electric blankets are equipped with heaters and temperature detection wires installed in a predetermined pattern throughout the blanket, and the heat generation of the heater is controlled using a three-terminal semiconductor control element such as a thyristor triax based on the electric signal from the temperature detection wires. It's summery. Also, if you pay attention to the mounting pattern of the heater, the temperature distribution is dense at the feet so that the head is cold and the feet are warm, and it becomes more coarse towards the chest. There are also models that allow you to turn on and off the chest and foot heaters.

Figure 1 shows the pattern of the heater and temperature detection wire of a conventional electric blanket.The heater H is installed in the blanket body 1 so that it is gradually looser in the chest area B than in the foot area A. The temperature distribution is determined by In addition, K in the figure indicates a temperature detection line, and 2 indicates a connection part.

Figure 2 shows another example of a conventional electric blanket, which is equipped with a foot heater _H1 and a chest heater _H2 .
The chest heater _H2 can be turned on and off by a switch 3, and heating only the feet or chest and feet can be selected.

The temperature pattern of head cold and foot heat in such conventional electric blankets is fixed or can only be roughly selected by turning on and off the chest heater. Therefore, there has been a demand for an electric blanket that can be adapted to the user's preferred head-cold, foot-and-heat pattern.

The present invention takes into consideration the above-mentioned conventional drawbacks and makes it possible to arbitrarily vary the ratio of heat generation from the foot heater to the heat generation from the chest heater. This will be explained based on Figure 4.

Figure 3 shows the circuit of the electric blanket according to the present invention,
FIG. 4 shows the installation pattern of the heater and temperature detection wire of the electric blanket.

In the figure, 1 is the blanket body, A is the foot part, B is the chest part, _H1 is the foot heater, _H2 is the chest heater, K is the temperature detection line, and 2 is the connection part. The foot heater
H ₁ and chest heater H ₂ are connected in parallel with each other, and a 3-terminal semiconductor control element for main control (hereinafter referred to as the main control element) is installed in the common energization circuit of both heaters H ₁ and H ₂ .
The SCRs ₁ are connected in series, and a second 3-terminal semiconductor control element (hereinafter referred to as a second control element) SCR ₂ is connected in series in the single current-carrying circuit of the chest heater _H2 . The temperature detection line K has a well-known structure in which a temperature-sensitive material P whose resistance, impedance, etc. changes with changes in temperature is interposed between two signal lines _K1 and _K2 , and is connected to a power source and connected to the above-mentioned Signal line K ₁ and
A pulse generating element NL such as a neon lamp, diac, or SBS and the primary winding of a pulse transformer T are connected in series between _K2 . Said one signal line
A variable resistor VR ₁ and a resistor R ₁ are connected to the current-carrying circuit of K ₁ , and these temperature detection wires K and resistors
R ₁ and variable resistor VR ₁ constitute a temperature detection circuit, and pulse generation element NL and pulse transformer T constitute a pulse generation circuit.

A zero-volt ignition circuit Z is connected to the secondary side of the pulse transformer T, and its output signal is applied to the gate of the main control element _SCR1 . Note that the contents of the zero-volt ignition circuit Z are not directly related to the present invention, so they have been simplified.

A variable resistance is connected in parallel to the chest heater _H2 .
A series circuit of VR ₂ , resistors R ₂ and R ₃ is connected, and a second pulse generating element D made of a diagonal or the like is connected between the connection point of the resistors R ₂ and R ₃ and the gate of the second control element SCR ₂ . Connect these variable resistors VR ₂ , resistor R ₂ ,
R ₃ and the second pulse generating element D constitute a phase control circuit.

Note that 4 in the figure represents a switch, and 5 represents a power source.

The electric blanket of the present invention is constructed as described above, and its operation will now be described. In Fig. 3, when the temperature of the blanket body 1 is low, the resistance of the temperature-sensitive material P of the temperature detection line K is large, so the voltage between the signal lines _K1 and _K2 is high, and the connection between the signal lines _K1 and _K2 is high. The pulse generating element NL becomes conductive and generates a pulse voltage on the secondary side of the pulse transformer T. Furthermore, as the temperature of the blanket body 1 increases, the resistance of the temperature-sensitive material P of the temperature detection line K decreases, and a predetermined voltage cannot be obtained between the detection lines _K1 and _K2 , causing the pulse generating element NL to become non-conductive. Therefore, no pulse is generated.

When the pulse voltage is generated, the zero volt ignition circuit Z activates the main control element at the next zero V phase of the alternating current.
Give an output signal so that SCR ₁ can fire and apply it to the gate of the main control element SCR ₁ . This main control element
The conduction of SCR ₁ closes the energizing circuits of foot heater H ₁ and chest heater H ₂ .

By the way, the foot heater _H1 is the main control element.
Heat is generated due to the conduction of SCR ₁ , but since the second control element SCR 2 is inserted in the single energization circuit of the chest heater H ₂ , this chest heater _{H 2 is} connected to the main control element SCR ₁ and the second control element. Heat generation is also controlled by the conduction and non-conduction of element SCR ₂ .

The gate of the second control element SCR ₂ is a variable resistor.
Since it is connected to a phase control ignition circuit consisting of VR ₂ , resistors R ₂ , R ₃ , and pulse generating element D, the variable resistor
By varying the value of VR ₂ , the firing phase of the second control element SCR ₂ can be varied.

That is, when the resistance value of the variable resistor VR ₂ is increased to prevent SCR ₂ from firing, the chest heater H ₂ does not generate heat, and only the foot heater H ₁ is controlled to generate heat by the main control element SCR ₁ .

Also, if the resistance value of variable resistor VR ₂ is decreased and SCR ₂ is fired at the recognized conduction angle α, the phase angle of the power supply will be O~
Up to α degree, only the foot heater _H1 generates heat, and during a phase angle of α to 180 degrees, current flows to the chest heater _H2 in addition to the foot heater _H1 and generates heat. Next, when the resistance value of VR ₂ is further reduced and the conduction angle of SCR ₂ is made close to 180 degrees, there is no difference in the conduction angle of both the foot heater H ₁ and the chest heater H ₂ , and both heaters are controlled only by the main control element SCR ₁ . Becomes subject to control. Therefore variable resistance
If you select the value of VR ₂ , you will get foot heater H ₁ and chest heater H _2.
The proportion of heat generated by both the foot heater H ₁ and the chest heater H 2 when the second control element SCR ₂ is conductive _, and that of the foot heater H ₁ only when the second control element SCR ₂ is non-conductive It can be freely selected within the range of heat generation, and the user can obtain the temperature of head cold and foot heat that suits his or her essence.

In addition, in this invention, one temperature detection circuit detects and controls the temperature of the entire surface of the blanket, and only the heater is divided into two. It has a great practical effect, such as being able to be manufactured at a lower cost than a device with two sets of heaters.

Note that the control element of the present invention is not limited to a thyristor, as the same effect can be achieved by using two triaxes in addition to a thyristor, or by using a thyristor and a triax. This invention can also be applied to bed sheets.
Therefore, it is not limited to blankets.

[Brief explanation of the drawing]

Figures 1 and 2 are heater installation pattern diagrams of a conventional electric blanket, Figure 3 is an electric circuit diagram of an electric blanket according to an embodiment of the present invention, and Figure 4 is a heater and detection diagram of an electric blanket according to the present invention. It is a mounting pattern diagram of wires. 1... Blanket body, 2... Connection part, C... Blanket body, H ₁ ... Feet heater, H ₂ ... Chest heater, K
...Temperature detection line, K ₁ , K ₂ ... Signal line, P ... Temperature sensitive material, SCR ₁ ... Main control element, SCR ₂ ... Second control element, NL ... Pulse generating element, T ... ...Pulse transformer, _VR1 , _VR2 ...Variable resistor, Z...Zero volt ignition circuit, D...Second pulse generating element.

Claims (1)

[Scope of utility model registration request] A series connection body of the second 3-terminal semiconductor control element and the chest heater is connected in parallel with the foot heater, and a 3-terminal semiconductor control element for main control is connected in series to this parallel connection body, and the main control A control circuit into which a temperature signal is input from a temperature detection line for detecting the average temperature of the electric blanket is connected to the gate of the second three-terminal semiconductor control element, and a control circuit is connected to the gate of the second three-terminal semiconductor control element. An electric blanket connected to a phase control circuit controlled by conduction of the main control three-terminal semiconductor control element.