127results about How to "Accurate pressure measurement" patented technology

A method of manufacturing a sensor for in vivo applications includes the steps of providing two wafers of an electrically insulating material. A recess is formed in the first wafer, and a capacitor plate is formed in the recess of the first wafer. A second capacitor plate is formed in a corresponding region of the second wafer, and the two wafers are affixed to one another such that the first and second capacitor plates are arranged in parallel, spaced-apart relation.

A MEMS (micro-electro-mechanical system) getter microdevice for controlling the ambient pressure inside the hermetic packages that enclose various types of MEMS, photonic, or optoelectronic devices. The getter microdevice revolves around a platform suspended at a height above a substrate, and which is supported by supporting legs having low thermal conductance. Layers are deposited on the platform, such layers including a properly patterned resistor element, a heat-spreading layer and, finally, a thin-film getter material. When an electrical current flows through it, the resistor element heats the thin-film getter material until it reaches its activation temperature. The getter material then absorbs the gas species that could be present in the hermetic package, such gas species possibly impairing the operation of the devices housed in the packages while reducing their lifetime. The weak thermal conductance between the platform and the substrate helps in preventing damages to the surrounding devices when the MEMS getter microdevice is heated at its activation temperature, and it reduces the electrical power required for reaching the activation temperature as well.

The invention discloses a method for measuring gas pressure of a coal seam by a casing high-pressure hole sealing method. The method comprises the following steps: a, a hole is opened with a large-diameter drill bit, the depth of a casing can be increased by drilling, and then the casing with a flange at the outer end is sent into the hole; b, expansive cement mortar is injected into the hole in a grouting mode to enhance the casing; c, after the expansive cement mortar is solidified, drilling is carried out with a drill bit which is one size smaller than the large-diameter drill bit in step a along the original drilling center, the drilling is stopped when a coal seam is approached, and the expansive cement mortar is injected into a whole-hole section in a grouting mode for reinforcement after drilling cuttings are removed; d, after the expansive cement mortar is solidified, the hole is drilled with a drill bit which is one size smaller than the drill bit in step c along the original drilling center until the coal seam is penetrated; and e, the flange at the outer end of the casing is connected with a pressure gage to measure gas pressure. Large and small gaps and gap water around the drill hole can be effectively blocked in a high-pressure grouting method, an air leak channel is sealed, and rapid and accurate pressure measurement is realized.

An array-type capacitive pressure pulse wave sensor includes m rows of lower electrodes arranged in parallel with each other to extend substantially linearly in a direction approximately orthogonal to the extending direction of the artery at the time of measurement, n columns of upper electrodes arranged in parallel with each other at a prescribed distance from the m lower electrodes to extend in a direction crossing the extending direction of the m lower electrodes, and m×n capacitive elements formed at intersections of the m lower electrodes and the n upper electrodes. The m×n capacitive elements are arranged in a staggered manner when the pressure detecting portion is seen in two dimensions. Thus, it is possible to provide an array-type capacitive pressure pulse wave sensor that can be manufactured inexpensively and that ensures accurate and stable measurement of the pressure pulse wave.

In a quadrupole mass spectrometer which measures partial pressure strength according to a gas type in a vacuum system from ion current intensity, a quadrupole mass spectrometer with a total pressure measurement electrode has a total pressure measurement electrode for examining an ion density disposed in a demarcation space which is comprised of a grid electrode and an ion focusing electrode. And, a vacuum system is provided with only the quadrupole mass spectrometer which measures partial pressure strength according to a gas type in the vacuum system from an ion current intensity and does not have an ionization vacuum gauge other than the quadrupole mass spectrometer.

A balloon including: a pressure-receiving portion formed of an elastic material and forming an enclosed space; and a tubular portion formed integrally therewith. The balloon is configured to detect the air pressure in the pressure-receiving portion due to communication with a pressure detector through an opening end of the tubular portion. A transverse cross-section of the pressure-receiving portion orthogonal to the axial direction of the tubular portion has a flattened outer circumferential shape with an oblateness f=(A−B) / A, where A represents the length of a major axis of the outer circumferential shape and B represents the length of a minor axis thereof, being set to a range of 0.1≦f≦0.7 at a position at which the length A is at a maximum. The air pressure can be changed significantly and stably, and the precision of the pressure measurement can be increased.