The present invention provides a pressure change measuring apparatus and a pressure change measuring method, which are capable of detecting a change in pressure to be measured with respect to a time axis with high accuracy. Specifically, a reference value setting unit (60) included in a pressure change measuring apparatus (1) is configured to generate a reference value signal based on an output signal of a differential pressure measuring cantilever (4) under a predetermined state, and to output the reference value signal. An arithmetic processing unit (30) is configured to calculate the pressure change in pressure to be measured based on the output signal, the reference value signal, a volume of a cavity (10), a flowing quantity of a pressure transmission medium flowing into and out of the cavity (10) for every unit of a predetermined time period, and the like.

An airflow sensor for a heat sink has a first portion having a first electrical point of contact, a second portion have a second electrical point of contact, and a deformable portion made of an electroactive material electrically coupled to the first and second portions. The deformable portion has first electrical properties measured between the first and second electrical points of contact when there is no airflow and the deformable portion is in a first position, and has second electrical properties different than the first electrical properties when a source of airflow blows air against the deformable portion, thereby causing the deformable portion to extend to a second position farther away from the source of airflow than the first position. The airflow sensor can be incorporated into a heat sink for an electronic component.

Provided is a pressure detection device including: a pressure detection unit; and a flow channel unit provided with a flow channel and a pressure receiving portion. The pressure detection unit includes a pressure sensor including a diaphragm, and a pressure transmission portion which is disposed in a state where one end of the pressure transmission portion is in contact with the diaphragm and the other end thereof is in contact with the diaphragm, and transmits a pressure of a fluid received by the diaphragm to the diaphragm. The pressure transmission portion is disposed in a state where the diaphragm is displaced toward the flow channel and an urging force directed from the diaphragm to the diaphragm is received.

The flow channel unit includes: a pair of end flow channels disposed at an inflow port and an outflow port, respectively, and extending along in flow direction; a center flow channel including a pressure receiving portion having a thin film shape and disposed at a position sandwiched between the pair of end flow channels, a distance from an inner peripheral surface of the pressure receiving portion to an outer peripheral surface thereof being shorter than a distance from an inner peripheral surface of the pair of end flow channels to an outer peripheral surface thereof. The pair of end flow channels and the center flow channel are integrally formed of a flexible resin material, and the pressure detection portion is disposed such that the pressure of the fluid circulated through a flow channel is transmitted via the pressure receiving portion.

Apparatus and methods for designing a system that measures deflection at multiple points and in various axes and how it relates to flow measurement are described. A system for continuously measuring the mass flow of a media includes one or more cartridges, one or more displacement sensing devices, and a processor. The one or more cartridges are connected serially between an inflow and outflow media pipe. The one or more displacement-sensing devices is configured to detect displacement changes of the one or more cartridges at two or more separate points on the cartridge(s) when the media flows through the cartridge(s). The processor is configured to calculate the flow of the media based on the detected displacement changes of the one or more cartridges at the one or more separate points.

A flow sensor includes a fluid chamber configured to receive a fluid. A diaphragm assembly is configured to be displaced whenever the fluid within the fluid chamber is displaced. A transducer assembly is configured to monitor the displacement of the diaphragm assembly and generate a signal based, at least in part, upon the quantity of fluid displaced within the fluid chamber.

A pressure measuring cell or flow rate measuring cell includes a pipe piece in which either a membrane to which a pressure that is to be measured is applied or an orifice plate is arranged in the cross-section through which a fluid flows, wherein the membrane or orifice plate and the pipe piece are formed together and interconnected via a solid-body joint, where a sensor is arranged outside the pipe piece near the solid-body joint or is accessible from this side, a tubular carrier part diverts forces past the solid-body joint when the pressure or flow rate measurement cell is being installed, and where the tubular carrier part has an inner diameter that is greater than the outer diameter of the pipe piece and has a wall in its cross section with a central circular opening, into which the pipe piece shortened to the thickness of the wall is inserted.

A vortex flowmeter for measuring a flow rate of a fluid. The meter includes a flowtube, a bluff body, and a vortex sensor. The bluff body, which is positioned in the flowtube, sheds vortices in the fluid when the fluid flows through the flowtube and the vortex sensor detects the vortices and generates a vortex signal representing the detected vortices. A pressure sensor arrangement is configured to detect a differential pressure in the fluid between a first location upstream of at least a portion of the bluff body and a second location downstream of at least a portion of the bluff body and generate a differential pressure signal representing the pressure differential between the two locations. The flowmeter determines the fluid flow rate based on the pressure differential.

A volume fraction meter that includes a flow meter coupled to a flow line. The flow line includes a turned portion and the flow meter is positioned upstream from the turned portion with respect to a flow direction. The flow meter is configured to measure a volumetric flow rate of a multiphase fluid flowing in the flow direction through the flow line. The flow line includes a nozzle opening downstream the turned portion. The volume fraction meter also includes a strain gauge coupled to the flow line between the flow meter and the turned portion of the flow line. The strain gauge is configured to measure a bending strain on the flow line upon discharge of the multiphase fluid through the nozzle opening, such that the bending strain and the volumetric flow-rate provide inputs for determining a mixture density of the multiphase fluid.

A pilot-operated relief valve assembly can include a relief valve, and a pressure detection assembly. A valve lift factor or indicator of relief flow can be determined based on pressure measurements gathered by the pressure detection assembly.