What are the key materials of the jump temperature controller?

What are the key materials of the jump temperature controller? Jump temperature controller is a temperature-sensitive switch element, widely used in coffee pot, rice cooker, electric water heater, vacuum cleaner and soymilk machine and other small household appliances, used as overtemperature protection, has the advantages of simple structure, safe and reliable, reliable action simply, no pulling arc, less radio interference, long service life, low cost. The key materials of the jump temperature controller are bimetallic sheet, silver contact and beryllium copper sheet.

These three materials have a direct impact on the quality of the jump thermostat. The failure of jump temperature controller can be mainly attributed to three points: contact bonding failure, spring (beryllium copper shrapnel) fracture and temperature drift failure. The following will be discussed in detail, please pay attention to.

Jump temperature controller is a switch element to control the temperature, widely used in water dispenser, rice cooker, microwave oven, electric oven and other household appliances, its reliability directly affects the whole electrical performance and product grade. At present, the life of domestic temperature controller products is generally about one hundred thousand times, compared with foreign two hundred thousand times has a big gap. In order to improve the market competitiveness of domestic household appliances, it is necessary to improve the reliability of domestic jump temperature controller.

Contact failure is one of the most common failure modes for the jump temperature controller, accounting for about 80% of the total failures. Contact bounce is a common phenomenon of switch components, is the main cause of contact failure, it causes contact mechanical wear, ignition arc, aggravate contact electrical wear and material erosion, in serious cases, will make the contact stick together, will seriously reduce the service life and reliability of the jump temperature controller.

Therefore, the research on the phenomenon of contact bounce and the analysis of its main influencing factors can provide a basis for the suppression of contact bounce and the evaluation of the effect of the optimal design of sheet spring. The spring is one of the key components to ensure the normal operation of the jump temperature controller. Its mechanical parameters have a great influence on the operating performance and the bouncing performance of the contacts. At present, when solving the mechanical characteristics of sheet spring, scholars at home and abroad mostly adopt the calculation method based on the theory of small deformation, ignoring that sheet spring is a thin-walled element and geometric nonlinear problems occur in the bending deformation process. Therefore, the solution results obtained do not accord with the actual situation of sheet spring. In this paper, the geometric nonlinear finite element method is used to calculate the mechanical characteristics of the vane spring. On the basis of this, the optimal design of the vane spring is carried out to improve the dynamic bouncing performance of the contact, which has practical significance to improve the reliability level of the jump temperature controller. In this paper, KSD301 jump temperature controller is taken as the research object. Firstly, the phenomenon of the spring contact bounce is studied, and the influence of the structure size of the spring on the spring contact bounce is analyzed, and then the mechanical characteristics of the spring are calculated. Finally, the optimal design method of the structure size of the spring is studied by taking the maximum of the prepressure of the spring when the constraint range is met.