Abstract:
First capacitance pressure sensor (70A, B) has a fusion bonded single crystal structure (sapphire with cavity). Second one (70A, B) has an elongated and thick single crystal structure. Third one (70A, B) uses the electric field emanating from the back sides of the capacitor plates. First differential pressure transmitter uses a process barrier (71) and an elongated member as a sensor (70A, B). Second differential pressure transmitter uses single crystal structures with stress isolation members as sensors (70A, B). Basically thick slab cavity capacitance sapphire sensors are directly exposed to a process fluid. Slab: 15x3x2 cubic mm, cavity cross section: 1mm x 0.5 micro m, capacitance: 42 pF.
Abstract:
A wireless field device (34, 50, 70, 80, 91, 100) is disclosed. The field device (34, 50, 70, 80, 91, 100) includes a wireless communications module (32) and an energy conversion module (38) . The wireless communications module (32) is configured to wirelessly communicate process-related information with another device. The energy conversion module (38) is coupled to the wireless communications module (32) . The energy conversion module (38) is configured to couple to a thermal source, and to generate electricity from thermal potential energy in the thermal source.
Abstract:
A pH sensor (10) has an electrode assembly (20) with an electrode (34) with a core (38) of an electrochemically inert insulating or semi-conductive material, and is coated with an electrically conductive, electrochemically sensitive coating (40). The preferred core (38) is insulating and made of alumina, with a thin coating (40) of iridium oxide deposited over at least a portion of the outer surface of the core (38). The coating (40) is carried to a region (70) remote from the sensing surface (46) and is used for making electrically conductive connections (52, 54) that lead to remote circuitry (32). The core (38) is made in a form that can be supported and held in an insulating, electrochemically inert, deformable material (36) that is sealed around the outer surface of the coating (40) on the core (38) to prevent leakage of chemicals being sensed. An outer housing (14) also permits sealing quite easily into access ports on which the sensor housing (14) is mounted.
Abstract:
A solid state, thin film moisture sensing element (12) is disclosed. The sensing element (12) is fabricated by thin film deposition of at least a pair of two layer electrodes (32 and 34) on an insulating surface (27). The active surface of the element (12) is then coated with a layer of hygroscopic material (30) and placed in a diffusion limiting housing (14) to complete the sensing element assembly (10).
Abstract:
A thin film platinum resistance thermometer capable of operation at elevated temperatures includes a benign dielectric layer (24) covering the thin film platinum resistance temperature sensing element (14) and a barrier layer (26) overlying the dielectric layer (24). The barrier layer (26), which is preferably titanium dioxide, resists diffusion or contaminants which would alter the electrical characteristics of the sensing element (14), while permitting diffusion of oxygen through the barrier layer (26).
Abstract:
A thin film platinum resistance thermometer capable of operation at elevated temperatures includes a benign dielectric layer (24) covering the thin film platinum resistance temperature sensing element (14) and a barrier layer (26) overlying the dielectric layer (24). The barrier layer (26), which is preferably titanium dioxide, resists diffusion or contaminants which would alter the electrical characteristics of the sensing element (14), while permitting diffusion of oxygen through the barrier layer (26).
Abstract:
L'invention se rapporte à un capteur de pH (10), qui comprend un ensemble électrode (20) comportant une électrode (34) avec un noyau (38) en matériau isolant ou semiconducteur électrochimiquement inerte, et qui est recouvert d'un enrobage électroconducteur et sensible électrochimiquement (40). Le noyau préféré (38) est isolant et produit à partir d'alumine, avec une mince couche d'enrobage (40) d'oxyde d'iridium déposé sur une partie au moins de la surface externe du noyau (38). La couche d'enrobage (40) est portée jusqu'à une région (70) éloignée de la surface de détection (46) et est utilisée pour produire des connexions électroconductrices (52, 54) qui conduisent au circuit éloigné (32). Le noyau (38) est conçu sous une forme qui peut être soutenue et maintenue dans un matériau isolant déformable et électrochimiquement inerte (36) qui est scellé autour de la surface externe de la couche d'enrobage (40) sur le noyau (38) pour empêcher toute fuite des substances chimiques devant être analysées. Un boîtier extérieur (14) est également prévu pour permettre de sceller facilement le capteur dans les trous d'accès sur lesquels est monté le boîtier (14) du capteur.
Abstract:
A pressure sensor (100, 222) integrally formed in the shape of a beam (102) around a central channel. The beam (102) has an integral blind end (104) that is pressurized by the fluid. The beam has an opposite end (106) that is shaped to provide a stepped corner (107) with a gap (108) opening at the base of the stepped corner (107), where the gap (108) and isolated from the fluid. A sensing film (112) in the channel adjacent the blind end (104) has an electrical parameter that varies with pressure and electrical leads (110) that extend from the channel and out the gap. A seal (115) fills the gap (108) around the leads (110) and the seal (115) fills a portion of the stepped corner (107). The sensor (100) is preferably formed by direct bonding of single crystal alumina layers (114, 116). Applications include industrial pressure transmitters, aerospace and turbine engine pressure sensing.
Abstract:
A solid state, thin film moisture sensing element (12) is disclosed. The sensing element (12) is fabricated by thin film deposition of at least a pair of two layer electrodes (32 and 34) on an insulating surface (27). The active surface of the element (12) is then coated with a layer of hygroscopic material (30) and placed in a diffusion limiting housing (14) to complete the sensing element assembly (10).