The micromachined liquid flow sensor devices are enclosed with silicon nitride film as passivation layer to protect device from penetration of liquid into device and avoid the damages of erosion or short circuit etc. One thin layer of silicon dioxide is deposited underneath the silicon nitride layer to enhance the adhesion and reliability of the passivation layer for various applications. The incorporation of silicon dioxide film had successfully provided reliable passivation protection especially for microfluidic devices application. In order to avoid flow turbulence caused by wire bonding wires, the wire bonding wires are omitted by deploying through-substrate conductive vias whereas connected to the carrier printed circuit board of sensor chip. The present invention disclosed a novel micromachining process and designed structure to form hermit sealing between the sensor chip and the carrier printed circuit board. The hermit sealing underneath the sensor chip can protect the bonding connections from exposing to liquid flow media and avoid short circuitry or induce undesired chemical corrosion. More particularly, the embodiments of the current invention relates to formation steps of a micromachined liquid flow sensor including passivation and protection of bonding connection to its carrier printed circuit board, which is therefore capable to offer superb accuracy and reliability for liquid flow measurement.

The present disclosure relate to a controller system and method for use in storage-style water heating systems that offers significant opportunities for energy saving. The controller system can adjust the water heating system in response to energy demand patterns of user fixtures. The controller system can detect quantity of heated water usage and produce a heated water usage profile. The controller system can determine the quantity or volume of the used heated water without a mechanical flow meter. The controller system can include a cost-effective, accurate, and easy-to-install water temperature sensors that provide measurements of the differentials between water temperatures without direct contact with the water. The water temperature sensors can be cost-effective and easy-to-install sensors that are attached to the water pipes through a strap or other attachment methods.

The present disclosure provides an air flow rate measuring including a casing and a sensor. The casing includes a main-bypass passage that defines an inlet and an outlet, a sub-bypass passage that branches off from the main-bypass passage at a branching area, and a guiding wall that changes, at a position upstream of the branching area, a flow direction of the passing air taken in from the inlet. The inlet and the guiding wall are arranged in an arranging direction along a flow direction of the intake air in the duct. The guiding wall includes an inlet side surface that faces the inlet and is not perpendicular to the arranging direction.

A mass flow control apparatus having a monolithic base. The monolithic base has a gas inlet, a gas outlet, a first flow component mounting region, a second flow component mounting region, and a third flow component mounting region. The first flow component mounting region has a first inlet port and a first outlet port, the first inlet port being fluidly coupled to the gas inlet of the monolithic base. The third flow component mounting region has a first sensing port fluidly coupled to the gas outlet of the monolithic base.

In a flow path forming structure, axial runout of a shaft relative to a central axis generated when the shaft is inserted into the flow path is suppressed. This structure includes a flow path along which a fluid passes, and a shaft body that is inserted into the flow path. An upstream side of the shaft body and an inner circumferential surface of the flow path have a plurality of contact positions at different phases, and a downstream side of the shaft body and an inner circumferential surface of the flow path have a plurality of contact positions at different phases. The fluid flows through gaps between the shaft body and the inner circumferential surface. The contact positions on one of the upstream and downstream sides are at different phases from all of the contact positions on the other one of the upstream and downstream sides.

A multi-purpose Micro-Electro-Mechanical Systems (MEMS) thermopile sensor able to use as a thermal conductivity sensor, a Pirani vacuum sensor, a thermal flow sensor and a non-contact infrared temperature sensor, respectively. The sensor comprises a rectangular membrane created in a silicon substrate which has a thin polysilicon layer and a thin residual thermal reorganized porous silicon layer both attached on its back side, and configured to have its three sides clamped to the frame formed in the silicon substrate which surrounds and supports the membrane and the other side free to the frame, a cavity created in the silicon substrate, positioned under the membrane and having its flat bottom opposite to the membrane, its three side walls shaped as curved planes and the other side wall shaped as a vertical plane, a heater or an infrared absorber positioned on the membrane, close to and parallel with the free side of the membrane and a thermopile positioned on the membrane and consists of several thermocouples connected in series and having its hot junctions close to the heater and its cold junctions extended to the frame.

A thermal mass flow sensor 10 enclosed airtightly in a sealed container 11 under an inert atmosphere for the purpose of suppressing disappearance of a coating layer on sensor wires 13a and 13b in association with use at a high temperature, further comprises an air release pipe 16 that is a pipe which brings an internal space and outside of the sealed container 11 in airtight communication with each other through an air release hole 16a that is a through-hole formed in an outer wall of the sealed container 11. An end of the air release pipe 16 on an opposite side to the air release hole 16a is sealed by plastic deformation to form a sealed part 16b. Thereby, after forming the sealed container 11 under a normal atmosphere, the internal space of the sealed container 11 can be closed airtightly. The sealed part 16b may be further sealed by welding. The sealed container 11 can be assembled easily and accurately in this way, and degradation in airtightness of the sealed container 11 in association with use at a high temperature can be suppressed.

A retractable fitting with a stopcock has a stopcock housing for connection to a pipe or process chamber. The housing has a connection opening into the pipe or process chamber. A shut-off body is rotatable about a pivot axis relative to the stopcock housing, and has a passage hole that merges in an open state of the stopcock into the connection opening of the stopcock housing, the connection opening being closed by the shut-off body in a closed state. A support element in the passage hole is introduced in the open state through the connection opening into the pipe or process chamber. A plurality of flushing lines are operable to conduct a flushing medium, the plurality of flushing lines being accessible from outside of the stopcock and being connected to and/or opening into the passage hole of the shut-off body at least in the closed state of the stopcock.

The disclosure relates to a method for measuring the size of a leakage flow of a seal. In exemplifications of the disclosure, a leakage sensor is provided on a leakage side of the seal, said leakage sensor comprising at least one heating element and at least two temperature sensors which are in heat-transferring connection with the leakage flow. In exemplifications, the following steps are utilized: continuous or intermittent detection of a temperature difference in the leakage flow over a section of a leakage channel through which the leakage flow flows by means of the temperature sensors, wherein a predetermined constant reference heat quantity is simultaneously generated by the heating element and transferred into the leakage flow in the section of the leakage channel, and determination of the size of the current leakage flow as a function of the currently detected temperature difference; or continuously or intermittently setting a constant temperature difference in the leakage flow over a section of a leakage channel through which the leakage flow flows by generating a variable amount of heat with the heating element and transferring the amount of heat into the leakage flow in the section of the leakage channel, and determining the size of the current leakage flow as a function of the currently generated amount of heat.

Example systems, apparatuses, and methods are disclosed sensing a flow of fluid using a thermopile-based flow sensing device. An example apparatus includes a flow sensing device comprising a heating structure having a centerline. The flow sensing device may further comprise a thermopile. At least a portion of the thermopile may be disposed over the heating structure. The thermopile may comprise a first thermocouple having a first thermocouple junction disposed upstream of the centerline of the heating structure. The thermopile may further comprise a second thermocouple having a second thermocouple junction disposed downstream of the centerline of the heating structure.