Differential pressure transmitter

Abstract

The present invention discloses a differential pressure transmitter. The differential pressure transmitter comprises a pressure leading seat and a sealing cover, the sealing cover covers the pressure leading seat, a diaphragm type pressure sensor is arranged in the sealing cover, a lead port is formed in the top of the sealing cover, the diaphragm type pressure sensor is connected with a signal lead, and the signal lead outwards penetrates out of the lead port. A lead connector is wrapped on the signal lead, the lead connector is arranged in the lead port in a blocking mode and sealed with the lead port, a negative pressure oil injection hole is further formed in the sealing cover, and an oil plug is arranged in the negative pressure oil injection hole. By the adoption of the differential pressure transmitter, when the internal pressure of the diaphragm type pressure sensor is too large, the diaphragm type pressure sensor has the tendency of being separated outwards, a liquid pressure transmission medium in the installation cavity is not prone to being compressed, the tendency of separation of the diaphragm type pressure sensor can be prevented to a certain extent, and a suspension type installation mode is adopted, the isolation diaphragm and / or the welding ring are / is prevented from abutting against the assembly part, the isolation diaphragm cannot deform in the installation process, and the influence of clamping stress on the measurement precision is avoided.

Description

technical field [0001] The invention relates to a pressure measuring device, in particular to a differential pressure transmitter. Background technique [0002] The core detection component of the capacitive differential pressure transmitter is the diaphragm capacitive differential pressure transmitter (diaphragm pressure sensor), which converts two different external pressure signals into corresponding capacitance changes, and the rear detection circuit is The change of capacitance is converted into an electrical signal, and the differential pressure value of the applied pressure can be obtained by processing and detecting the electrical signal. [0003] Diaphragm pressure sensor consists of two disc-shaped membrane seats, the edges of the two membrane seats are welded, a diaphragm deformation cavity is arranged between the two diaphragm seats, and a measuring diaphragm is arranged between the two diaphragm seats , the two diaphragm seats respectively run through a pressur...

AI Technical Summary

Problems solved by technology

[0005] 1. In the post-assembly process, the isolation diaphragm and / or welding ring is in contact with the assembly part. Affected by the clamping stress, the isolation diaphragm is prone to deformation, thereby promoting the flow of internal silicone oil, so that the measuring diaphragm of each transmitter The initial position of the chip changes in different situations, which affects the measurement accuracy;

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