According to an embodiment, a method for manufacturing a spring structure (glass spring structure) comprises: providing a mold substrate and a cover substrate comprising a glass material, said mold substrate and said cover substrate being connected, wherein a surface area of the mold substrate and/or of the cover substrate is structured to form a closed (or enclosed or sealed) surrounding cavity between the cover substrate and the mold substrate, tempering the cover substrate and the mold substrate to decrease the viscosity of the glass material of the cover substrate, and providing an overpressure in the closed surrounding cavity with respect to the ambient atmosphere, to cause, based on the decreased viscosity of the glass material of the cover substrate and the overpressure in the closed surrounding cavity with respect to the ambient atmosphere, bulging of the glass material of the cover substrate starting from the closed surrounding cavity to obtain a cover substrate provided with a surrounding glass bulge, and(subsequently) removing the mold substrate from the cover substrate to obtain the spring structure with the surrounding glass bulge.

A capacitance-based pressure sensor for measuring a process variable includes a metal sensor body, a diaphragm disposed within a cavity of the metal sensor to form a deflectable capacitor plate, and an insulator extending through the metal sensor body from an end wall to the cavity. The pressure sensor further includes an isolation tube in fluid connection with the cavity, the isolation tube extending into the insulator through the end wall, a stationary capacitor plate on a surface of the insulator in the cavity, the stationary capacitor plate spaced from the diaphragm, and an electrical lead wire connected to the stationary capacitor plate and extending through the insulator parallel to the isolation tube and exiting the insulator at the end wall. A fill fluid is within the isolation tube and the cavity to apply pressure to the diaphragm.

In an embodiment, a pressure transducer includes a first portion, a second portion, and a third portion. The third portion is positioned in a cavity contained in the second portion. In addition, a seal is placed in the cavity. The first portion and second include provisions for applying a downward pressure on the third portion when the first portion and the second portion are joined. The downward pressure is applied by the third portion to the seal to seal the cavity.

A pressure sensing apparatus which utilizes an electrolytic droplet retained between a first and second sensing electrode within a housing. Contact between the electrolyte droplet and the electrodes form electric double layers (EDL) having interfacial EDL capacitance proportional to interface contact area which varies in response to mechanical pressure applied to deform exterior portions of the housing. The electrolyte contains a sufficient percentage of glycerol to prevent evaporative effects. Preferably, the sensing electrodes are modified with depressions, hydrophilic and/or hydrophobic portions to increase central anchoring of the electrolyte droplet within the housing. The inventive pressure sensor provides high sensitivity and resolution which is beneficial to numerous applications, and is particularly well-suited for medical sensing applications.

A system and method detect the presence of an unacceptable quantity of gas molecules in the reference vacuum cavity of a capacitance diaphragm gauge (CDG). An independent pressure transducer has an active portion exposed to the reference vacuum cavity. The transducer includes a ring anode, a cylindrical inner wall surface that forms at least one cathode, and a magnet positioned with respect to the ring anode such that the magnetic flux of the magnet is generally aligned with the central axis of the ring anode. A high voltage source applies a voltage between the ring anode and the cathode. A current sensor senses a magnitude of any current flowing between the ring anode and the cathode via ionized gas molecules. A monitoring unit monitors the magnitude of the current sensed by the current sensor and activates an alarm when the magnitude of the current exceeds an acceptable magnitude.

The invention relates to a capacitive pressure transducer for measuring the pressure of a medium adjacent to the pressure transducer, which has a resilient measuring diaphragm, of which the first side is at least partially in contact with the medium and of which the second side, which faces away from the medium, comprises a measuring electrode and, for measuring a temperature, a resistance element made of a material having a temperature dependent resistance. Furthermore, the pressure transducer has a base body, which is arranged to oppose the second side of the measuring diaphragm, with a counter electrode, which forms a measuring capacitance with the measuring electrode. According to the invention, the resistance element is formed as a resistive layer disposed between the second side of the measuring diaphragm and the measuring electrode.

A process fluid pressure sensor assembly includes a pressure sensor configured to sense a pressure of a process fluid. The assembly includes a pressure sensor body formed of an insulating material. The pressure sensor includes a plurality of electrical contact pads which couple to a pressure sensing element of the body of the pressure sensor. An interconnect body is configured to fit over an end of the pressure sensor body. A plurality of electrical connectors carried in the interconnect body are in electrical contact with the plurality of electrical contact pads. A wiring harness attaches to the interconnect body and includes a plurality of wires which are electrically connected to the plurality of electrical connectors.

An assembly, comprising: a first ceramic body and a second ceramic body connected by means of a joint of an active hard solder, or braze, wherein the active hard solder, or braze, averaged over a continuous main volume, which includes at least 50% of the volume of the joint, has an average composition C.sub.M with a liquidus temperature T.sub.l(C.sub.M). An edge region of the joint, which contacts at least one of the ceramic bodies, has an average composition C.sub.E with a liquidus temperature T.sub.l(C.sub.E), which lies not less than 20 K, preferably not less than 50 K, and especially preferably not less than 100 K above the liquidus temperature T.sub.l(C.sub.M) of the average composition C.sub.M of the main volume.

A ceramic product includes a first ceramic part and a second ceramic part, wherein the first ceramic part is connected with the second ceramic part via a joint, wherein the joint comprises an active hard solder, or braze, characterized in that the joint has an inhomogeneous distribution of the components of the active hard solder, or braze, wherein at least at an interface between the active hard solder, or braze, and the ceramic, the at least one active component of the active hard solder, or braze, is enriched. For manufacture of the product, the active hard solder, or braze, material is provided in such a manner, that at least one surface section of at least one of the ceramic parts is first coated with at least one active component of the active hard solder, or braze, and that on the coated section, an alloy is provided, which, by melting of the alloy during the heating, alloys with the coating and forms a metal joint between the two ceramic parts.

The invention relates to a capacitive pressure measuring cell for detecting the pressure of a medium adjacent to the pressure measuring cell, comprising a ceramic elastic measuring membrane, the first side of which at least partially contacts the medium and the second side of which facing away from the medium comprises a measuring electrode, and a ceramic cylindrical basic body disposed opposite to the second side of the measuring membrane and comprising at least one counter electrode which forms a measuring capacitance with the measuring electrode.