Method for manufacturing temperature sensor and temperature sensor

Abstract

The invention relates to a method for manufacturing a temperature sensor. The method comprises the following steps: step one, selecting a required type of thermistor chip and a metal housing having acavity arranged inside for standby; step two, welding a lead to the thermistor chip by tin soldering; step three, immersing the thermistor chip in liquid silicone resin and enabling the surface of thethermistor chip to be in contact with the silicon resin, and forming a an encapsulation layer on the surface of the thermistor chip; step four, placing the thermistor chip with the encapsulation layer formed in the step two into a curing box, carrying out heating to form a cured encapsulation layer under the conditions of curing time of 10 to 20h and the curing temperature of 180 to 250 DEG C; and step six, placing the thermistor chip after the step four into a hollow metal housing and injecting the liquid silicone resin to fill the inside of the metal housing with the liquid silicone resin,thereby forming a filling sealing layer. The method has the beneficial effects: the prepared sensor has the good waterproof performance and can adapt to various work conditions; and the stability of the sensor is high.

Description

technical field [0001] The invention relates to the field of temperature sensors, in particular to a method for manufacturing a temperature sensor and the temperature sensor. Background technique [0002] The NTC temperature sensor is a high-precision thermistor element or chip, according to the different technical requirements of the actual application environment of the sensor, adopts safe processing techniques such as soldering, metal cladding (pressing) connection or micro-spot welding to reliably connect with the lead wire, and then carry out Encapsulation, insulation, moisture-proof and waterproof treatment, and the thermistor element or chip is sealed and fixed in the protective shell with epoxy resin encapsulation (potting) material, forming a stable and reliable component assembly that can meet specific temperature measurement and control requirements. [0003] The NTC temperature sensor in the prior art generally adopts epoxy resin as the outer insulating layer of ...

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Problems solved by technology

[0003] The NTC temperature sensor in the prior art generally adopts epoxy resin as the outer insulating layer of the thermistor chip or the filling material of the inner shell, which has the following disadvantages: one, the thermal conductivity of epoxy resin is low, and the temperature sensor made The thermal time constant is large, generally 15 seconds, which cannot meet the requirements of high response speed; second, epoxy resin has poor temperature resistance, the maximum temperature can only reach 150 ° C, and cannot work in high temperature environments; third, epoxy resin and The tightness and insulation of the metal shell are poor, and it is difficult to work in a humid environment. Water or moisture can easily penetrate into the inside of the NTC temperature sensor, affecting the reliability of the entire product; Fourth, after heating, the weight loss of the epoxy resin is serious. Poor stability, unable to meet users' stability requirements for NTC temperature sensors

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