Compressive sealing method for vehicle oxygen sensor

Abstract

The invention relates to the technical field of vehicle oxygen sensors, in particular to a compressive sealing method for a vehicle oxygen sensor. A sealing material used in the compressive sealing method for the vehicle oxygen sensor is prepared from h-BN or a complex of the h-BN or glass powder by molding, assembling, pressing and heating with alcohol serving as a solvent. According to the compressive sealing method for the vehicle oxygen sensor, the novel h-BN-based sealing material which can meet the usage requirements of a high-accuracy oxygen sensor on the aspects of sealing performanceand high-temperature structural stability is adopted, and the laminated structure of the h-BN and a flexible B2O3 liquid film can effectively reduce thermal stress concentration generated in a thermalcirculation process, so that the performance stability of the sealing material is improved. The h-BN-glass composite sealing material can effectively improve the airtightness, bonding strength and impact resistance of the sealing position of the oxygen sensor.

Description

technical field [0001] The invention relates to a sealing method, in particular to a compression sealing method of an oxygen sensor for a vehicle. Background technique [0002] In order to ensure that the oxygen sensor can work normally, from low temperature to high temperature environment, the sealing material must provide sufficient airtightness to block the mixture between the vehicle exhaust and the reference atmosphere, otherwise it will reduce the electromotive force on both sides of the YSZ electrolyte, Get wrong information about car exhaust concentration. If the performance of the sealing material deteriorates rapidly, it will lead to the failure of the entire oxygen sensor product. In addition, the application environment of the sealing material in the oxygen sensor is very harsh, and it needs to have good insulation, chemical stability, temperature resistance and excellent thermal vibration resistance. Compared with the tubular oxygen sensor, the chip oxygen sen...

AI Technical Summary

Problems solved by technology

Since the pressure-sealed structure belongs to the stuffing seal, there is permeation leakage inside the sealing material, and the interface leakage between the sealing material and adjacent components, all of which require a high compressive stress to maintain the good airtightness of the sealing material. This compressive stress can cause the ceramic sensing chip to break

In addition, the oxygen sensor is in the high pressure of the vehicle exhaust and the low pressure of the reference chamber at the same time, and this pressure difference will also lead to the intensification of gas leakage in the sealing material

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