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.

A counter to monitor an amount of tool use that includes a fluid passage (23) with an inlet (21) and an outlet (22). A piston (30) and sensor target (50) (e.g., magnet) are positioned along the passage and are biased towards a first position by a biasing member (40). When the tool is not in operation, the piston and sensor target are located at a first position due to the biasing force. When the tool is in operation, fluid moves along the fluid passage. A force applied by the moving fluid on the piston and sensor target overcomes the force applied by the biasing member and moves the piston and sensor target along the fluid passage to a second position. A sensor is configured to sense the sensor target at the second position. A processing circuit (62) determines the tool usage based on the detection of the sensor target at the second position by the sensor.

A counter to monitor an amount of tool use that includes a fluid passage (23) with an inlet (21) and an outlet (22). A piston (30) and sensor target (50) (e.g., magnet) are positioned along the passage and are biased towards a first position by a biasing member (40). When the tool is not in operation, the piston and sensor target are located at a first position due to the biasing force. When the tool is in operation, fluid moves along the fluid passage. A force applied by the moving fluid on the piston and sensor target overcomes the force applied by the biasing member and moves the piston and sensor target along the fluid passage to a second position. A sensor is configured to sense the sensor target at the second position. A processing circuit (62) determines the tool usage based on the detection of the sensor target at the second position by the sensor.

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.

Flow sensors are provided that can monitor flow conditions. The flow sensor includes a gauge that provides a first level of information about flow through the sensor, and an indicator associated with the gauge that can provided a second level of information about flow through the sensor. The indicator might be in the form of a dial that can rotate about the gauge and might include a locked position for monitoring flow and an unlocked position to rotate the dial about the gauge to reposition the dial. Vanes in the flow sensor remove turbulence in the flow sensor to settle any noise that would otherwise register in the first level of information about flow through the sensor. The plunger with a rounded upstream face also helps to settle any such noise.

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-rate sensor is provided with a lead frame, a semiconductor chip that is disposed on one surface of the lead frame, and in which a diaphragm including a void portion on the lead frame side is formed, a flow rate detecting unit that is formed on the one surface including the diaphragm of the semiconductor chip, and resin that includes a flow passage opening portion exposing at least a portion of the flow rate detecting unit formed on the diaphragm, and covers the lead frame and the semiconductor chip. A lower side resin portion of the resin covering another surface side of the lead frame, on an opposite side to the one surface side thereof, has a thinned portion that is thinner than a periphery thereof in a region facing a peripheral edge portion of the diaphragm.

A flow-rate sensor is provided with a lead frame, a semiconductor chip that is disposed on one surface of the lead frame, and in which a diaphragm including a void portion on the lead frame side is formed, a flow rate detecting unit that is formed on the one surface including the diaphragm of the semiconductor chip, and resin that includes a flow passage opening portion exposing at least a portion of the flow rate detecting unit formed on the diaphragm, and covers the lead frame and the semiconductor chip. A lower side resin portion of the resin covering another surface side of the lead frame, on an opposite side to the one surface side thereof, has a thinned portion that is thinner than a periphery thereof in a region facing a peripheral edge portion of the diaphragm.

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.