Development of pressure-sensitive electric blanket control board

The electric blanket is designed according to the heating principle of the electric heating wire. Generally, the overall linear electric heating wire heating scheme is adopted. The high and low gears are set by adjusting the resistance of the switch to control the heating power. The working mode of the electric blanket is the overall continuous heating method or timing. heating method. There are mainly the following three disadvantages: first, the overall continuous heating method adopted by the electric blanket is likely to cause discomfort, especially during long-term use, it will produce a burning sensation, resulting in a decline in the user's sleep quality; second, The heating area of the traditional electric blanket is fixed, the energy consumption is large during use, and the phenomenon of electric energy waste is relatively serious; thirdly, the automatic control function of the traditional electric blanket is not perfect, which has certain potential safety hazards, and is prone to local overheating, which may cause fire accidents.

1. The development principle of the pressure-sensitive sub-control electric blanket

1.1 Innovative Principles of Energy Conservation and Emission Reduction

The electric blanket is equipped with a multi-point pressure sensing module and an automatic control switch module to realize the automatic pressure-sensitive sub-control and sub-area heating of the electric blanket. The interior of the electric blanket is divided into multiple heating areas. The heating wires in each area are connected in parallel with the bus switch, and are controlled by the attached pressure sensor and automatic switch feedback. They do not interfere with each other and work independently. Feedback to realize independent heating only on the pressing area of the human body.

1.2 Function upgrade plan

1) The temperature measurement module, timing module and white control switch are set on the control bus to realize accurate monitoring of working temperature and timing work, effectively reduce the heating time at full power, and improve human comfort and safety.

2) Set the preheating function mode. This mode adopts global heating to improve the comfort of the user during initial use. When the set temperature or set time is reached, it will automatically switch to the pressure self-control mode to improve the energy-saving effect of the product.

2. The technical scheme of the pressure-sensitive sub-control electric blanket

2.1 Working principle of pressure sensing control module

The inside of the electric blanket is divided into areas, and the heating wires are arranged separately in each area, and the heating wires are connected in parallel between each area. Independently controlled pressure-sensing switches are configured in each domain. When the human body presses the pressure-sensing switch, the conduction circuit transmits a signal to the single-chip microcomputer, and the single-chip microcomputer controls the gate. The gate element is responsible for connecting the heating wire circuit to make the heating wire work.

2.2 Design of pressure sensing detection module

The tact switch is composed of two insulating sheets. Store the tact switch with the two insulating sheets, adjust the angle of the two insulating sheets to form a shell shape, and improve the sensitivity of the induction. In addition, a silicone sleeve is wrapped around the entire exterior of the pressure-sensing detection module, which is waterproof and electricity-proof, improving safety and lightly touching the two routes of the lead-out switch. Connect the microcontroller for signal processing. When the human body presses the pressure-sensitive switch S1 through its own gravity, the pressure-sensitive switch is turned on and sends a high-level signal to the P2.0 interface of the single-chip microcomputer. A high-level signal will be sent from the P1.7 interface to the thyristor, thereby turning on the circuits at both ends of the thyristor, connecting the heating wire to the power supply, and heating the area one. Similarly, when the human body presses the pressure-sensitive switch S2 through its own gravity, it will send a high-level signal to the P2.1 interface of the single-chip microcomputer, and the single-chip microcomputer outputs a high level from P1.7 to heat the area 2. Each heating area and switch adopts parallel processing, does not interfere with each other, and works independently.

The principle of setting the preheating mode: set the temperature control sensor, timer and self-control switch on the bus, and transmit the collected temperature information to the single chip microcomputer. off, and then control the working mode and state of the electric blanket.

Temperature control monitoring module design: add a temperature measurement module on the bus. Place the thermistor temperature measuring head of the temperature measuring module inside the electric blanket. When the set temperature is reached, the single-chip microcomputer control relay is disconnected, and the total circuit stops working.

Timing and automatic control switch module design: add a timing module on the bus. Connect the timing module and the temperature measurement module in series. When the set time is reached, the single-chip microcomputer control relay is disconnected, and the total circuit stops working.

Single-chip microcomputer control system design: the pressure sensing module is turned on, and one end of the interface is placed at a high level. After the single-chip microcomputer receives the high-level signal, it will output a high level at the other end of the interface through the internal self-written program to control the thyristor. The power supply is connected to the heating wire in this area to generate electricity.

Heating wire design in the block area: Silicone rubber heating wire is used, so that the heating power in each area is 20w. A 3.6m heating wire is coiled in each area, wound in an "s" shape, and the safety distance between two adjacent heating wires is 75mm to prevent overheating caused by mutual heating. Analyze the structure of the human body, place the pressure sensor switch in the middle and upper area of the electric blanket, and control the heating wire in the same area as the human body.

Summarize

The development plan of the pressure-sensitive sub-control electric blanket provides a simple and easy idea for the innovation and upgrading of traditional industrial products. The technical development is not difficult, and it is suitable for general scientific and technological personnel. Because the technical content and solutions it adopts are the transplantation and integration of mature technologies, the performance of new products is stable and the cost is not increased much. Due to the strong support of the home energy emission reduction policy, the overall image of the product has been greatly improved, and it can be quickly promoted in the market.

The above is the development example of the pressure-sensitive separate control electric blanket introduced by Shenzhen Zuchuang Microelectronics Co., Ltd. If you have development needs for electric blanket solutions, you can trust us. We represent a variety of single-chip microcomputers, voice chips, dual-mode Bluetooth ICs, and wifi chips. Brands include Songhan MCU, Yingguang MCU, Jerry Bluetooth, Ankai Bluetooth, Allwinner, and Realtek. Our technical services include: PCB design, MCU development, Bluetooth solution, software and hardware custom development, APP development, small program development, WeChat official account development, etc. It can also undertake the design of intelligent electronic products, the development of living appliances, the research and development of beauty equipment, the application of Internet of things platform, the smart home control system, the development of TWS earphones, Bluetooth earphone speakers, the development of children's educational toys, the design of electronic education products, etc.