[The working principle of electric blanket] What is the principle of electric blanket and how does electric blanket work
Electric blanket, also known as electric mattress, is a kind of contact Type electric heating appliance, it will be specially made, the insulation performance of the soft cable type electric heating element is woven or sewn into the blanket in the shape of a coil, and it emits heat when it is energized. It is mainly used to increase the temperature of the bed when people sleep to achieve the purpose of heating. It can also be used for dehumidification and dehumidification of bedding. It consumes less power, can adjust the temperature, is easy to use, and is widely used. It has a history of more than 100 years. At present, a new type of non-radiation electric blanket has obtained national patents. Pregnant women, children and the elderly can use the non-radiation electric blanket with confidence. A contact type electric heating appliance. The soft cord-type electric heating element is woven or sewn into the blanket in a coiled shape, and it emits heat when it is energized. There are electric mattresses and electric heating pads that work similar to electric blankets.
For use in temperature-regulated electric blankets. The wire core is made of glass fiber or polyester wire, wrapped with flexible and flexible electric heating alloy wire (or foil tape), and covered with a nylon heat-sensitive layer or special plastic heat-sensitive layer, and then a copper alloy signal The wire is wound outside the heat-sensitive layer, and the outermost layer is coated with a layer of heat-resistant resin. When the temperature at any point on the electric blanket exceeds a predetermined value, the heat-sensitive layer on the corresponding heating wire changes from an insulator to a good conductor, so that the control circuit is turned on, the electric blanket is powered off, and the temperature control and safety protection are achieved. Purpose. Ordinary electric blankets without signal wire type electric heating elements are used. If temperature control is to be achieved, two types of temperature control elements are generally provided: one is an overheating safety thermostat. Each electric blanket needs about 8 to 9 pieces, which are connected in series On the electric heating element, it plays the role of safety protection; the other type is the thermostat controller, which is located at the head of the bed or at the hand to adjust the temperature. Electric blankets that use electric heating elements with signal wires only require a thermostatic controller.
IC is NE555 time base circuit; RP3 is a temperature adjustment potentiometer, its sliding arm potential determines IC’s trigger potential V2 and threshold potential Vf, and V5=Vf=2Vz. The 220V AC voltage is limited and stepped down by C1 and R1, rectified by D1 and D2, filtered by C2, and regulated by DW to obtain a voltage of about 9V for IC use. Turn on the power at room temperature, and the temperature gradually increases due to the adjusted V2 heating wire being energized and heated. As the temperature of the thermal sensor BG1 increases, its penetration current Iceo increases, and V2 and V6 increase. When V2>Vz, V6≥Vf, IC flips, ③pin becomes low potential, BCR stops heating wire of post and telecommunications office and stops heating, temperature begins to drop gradually, Iceo of BG1 gradually decreases, V2, V6 decrease. When V6 components are selected: BG1 can use PNP type germanium tubes such as 3AX and 3AG; BCR can use small plastic-encapsulated triacs above 400V, and other components can be selected according to the icons.
Production points: The thermal sensor BG1 can be drawn out with a temperature-resistant thin flexible wire, and put it together with the pin connector into a capacitor aluminum shell, and inject thermal conductive silicone grease to make a temperature probe. When using, just put the probe in the proper place.
What kind of wire is in the circle, is it a normal household wire?
Usually electric blankets are mainly composed of heating element, base core, fabric, power cord, junction box (connection between heating element and power cord), control switch (or thermostat), etc. The main structure is to attach the heating element to the base fabric, then connect the power cord, and then sew the sewn heating element and the base fabric with a mask to sew the electric blanket. When purchasing, pay attention to the following aspects:
(1) It must be a product that has passed the inspection of relevant departments or units to ensure product quality, so you should pay attention to whether the product has a production license number.
(2) There should be a clear and definite sign, which should reflect the specification, manufacturer and necessary prompts of the electric blanket.
(3) The area of the electric blanket is different, and the heating area is also different. Usually divided into single, double or triple electric blankets. When possible, choose a larger electric blanket as much as possible.
(4) Choose fabrics with good texture as much as possible.
(5) The power should not exceed 60W for a single person and 120W for a double person.
(6) Power-on inspection. Put it in the high temperature position, and touch the middle of the electric blanket with your hand for about 3 to 5 minutes. Such as thermostats are other types. The corresponding adjustment test can also be carried out, but the test time is longer.
(7) The electric blanket power controller should be complete, smooth, free of defects, flexible in use, with clear switch marks, and the power cord used should be double-sheathed.
In order to increase the life of the electric blanket and avoid accidents, it is necessary to use the electric blanket correctly. The methods are:
(1) When laying the electric blanket, you should choose an auxiliary one on the bed. Upholstered, then put on an electric blanket. Lay mattresses and blankets on top of it for extra warmth.
(2) Electric blankets should not be used for a long time. First, it is easy to waste energy. Second, it is easy to produce burning sensation.
(3) Do not pierce the electric blanket with metal products to prevent short circuit of the heating wire and cause personal injury or death.
(4) If the electric blanket is dirty, it cannot be washed with water directly, otherwise the electric insulation performance will be reduced, resulting in leakage.
