Capacitive pressure transducer with transition welding ring

Abstract

The invention provides a capacitive pressure transducer with a transition welding ring, aiming at solving the problem of long-term slow leakage, accidental damage and the like since welding among unmatched materials of an existing capacitive pressure transducer easily causes thermal stress and swelling stress. The capacitive pressure transducer comprises a mated shell, a fixed electrode, a tubular extraction electrode, a moving electrode and a pressure drawing opening which are assembled with the mated shell. The capacitive pressure transducer is characterized in that a transition welding ring is arranged between the mated shell and a welding base with collars and pressure drawing openings; the moving electrode, the transition welding ring and the welding base with collars and pressure drawing openings are made of the same material which has an expansion coefficient larger than those of materials of the fixed electrode with a mated capsulated structure, and are welded together; and the fixed electrode and the moving electrode are welded together by utilizing the transition welding ring. The capacitive pressure transducer is reasonable in structure design, is safe and reliable, can be used for effectively buffering thermal stress and swelling stress generated by welding among unmatched materials and reducing undue changes of materials in the welding process, and has high yield rate, so that the manufacture cost can be reduced, and the measurement accuracy and stability can be improved.

Description

technical field [0001] The invention relates to a capacitive pressure sensor, in particular to a fixed electrode that is matched and sealed with a moving electrode that has a larger expansion coefficient than the matching shell of the fixed electrode by means of a transitional welding ring, thereby realizing the connection between the moving electrode and the measured sensor. The parts in contact with the medium are all capacitive pressure sensors with a transition welding ring made of constant elastic corrosion-resistant alloy. It can be widely used in microelectronics, uranium enrichment and other high-precision measurements that require high reliability and small and micro ranges. Background technique [0002] Among the various sensors for measuring small and micro pressures, the capacitive pressure sensor presents an advantage. The most representative one is the 6 series capacitive pressure sensor produced by MKS Company of the United States. Take the Model 626 capacit...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a capacitive pressure sensor with a transitional welding ring, which solves the problems of thermal stress and expansion stress, long-term slow leakage and sudden damage caused by welding between mismatched materials in the existing capacitive pressure sensor. Possibility and other problems, its structural design is reasonable, safe and reliable in use, effectively buffering the thermal stress and expansion stress generated by welding between mismatched materials, reducing undue changes in materials during the welding process, high yield, and reducing Manufacturing costs, improved measurement accuracy and stability

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