Coating device and method for inner electrode of zirconium element of oxygen sensor

Abstract

The invention relates to a coating device and method for an inner electrode of a zirconium element of an oxygen sensor. A gas channel and a paste channel are formed in a nozzle. A paste outlet is formed in the bottom end of the paste channel. The bottom end of the gas channel is communicated with the bottom end of the paste channel. The upper end of the gas channel is connected to a compressed air pipeline through a gas pipeline. The upper end of the paste channel is connected to a paste storage barrel through a paste pipeline. The paste storage barrel is connected to a high-pressure gas pipeline through a pipeline. High-pressure gas flows into the paste storage barrel to eject paste out of the paste storage barrel, the paste enters the paste channel in the nozzle through the paste pipeline, compressed air flows to the gas pipeline and then flows into the gas channel in the nozzle, the paste pre-extruded out of the paste channel is atomized in an outlet of the paste channel through the gas in the gas channel and then sprayed to the inner wall of a tubular zirconium pipe so as to acquire the inner electrode in any shape, and the uniformity of the coating shape and the coating thickness is guaranteed. By the adoption of the coating device and method, the ideal coating effect can be obtained and the device and method are suitable for large-scale coating.

Description

technical field [0001] The invention relates to an internal electrode coating device and method for a zirconium element of an oxygen sensor. Background technique [0002] The oxygen sensor is used for closed-loop control of the engine, so as to ensure that the emissions of HC, CO and NOx during the life of the vehicle meet the regulatory requirements. This has played a vital role in reducing vehicle pollutant emissions and reducing environmental pollution. Zirconia oxygen sensors take advantage of the solid electrolyte properties of zirconia, which is conductive to oxygen ions at high temperatures. In this way, when the oxygen concentration on both sides of the zirconia, that is, the oxygen partial pressure, is different, the effect of oxygen ions migrating from one side to the other will occur, thereby generating a voltage signal. Specifically, the oxygen ion conductivity of zirconia can be expressed by the Nernst equation. [0003] U = ...

AI Technical Summary

Problems solved by technology

For the coating process of the inner electrode, the known methods include partial grouting blowing method and full grouting blowing method. However, these two methods need to consume more slurry due to the method of pouring the grout into the inner wall of the zirconium element. At the same time, due to the blowing of the gas, the viscosity of the slurry changes rapidly, resulting in uneven thickness of the coated slurry, which cannot achieve the desired effect.

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