Patent ID: 6089097
Filing Date: 2000-07-18
Classification: G01L,Y10T

Abstract:
A pressure transmitter for use in an industrial process control system for transmitting pressure on a process control loop, the transmitter comprising:I/O circuitry coupling to the loop for transmitting information on the loop; compensation circuitry receiving a pressure related signal and responsively controlling the I/O circuitry to transmit pressure information on the loop;a transmitter housing containing the I/O circuitry and the compensation circuitry;a mounting portion in the housing formed of a mounting portion material;a process barrier in the housing positioned between the I/O circuitry and the compensation circuitry which isolates the I/O circuitry from the compensation circuitry and the mounting portion;an elongated member formed substantially of a brittle, corrosion-resistant material which is different from the mounting portion material and is coupled to the mounting portion at a proximal end and having a passageway extending therethrough;a pressure responsive portion at a distal end of the elongated member for immersion in a fluid which is at a pressure related to the process fluid pressure and deforming in response to process fluid pressure; anda sensor coupled to the pressure responsive portion and having an electrical connection to the compensation circuitry through the passageway of the elongated portion and a sealed feed-through in the process barrier, wherein the sensor and electrical connection are isolated from process fluid by the elongated member;wherein the elongated member and pressure responsive portion include fusion bonds which are substantially free of foreign material.