Methods and apparatuses related to freeze resistant sensing assemblies are provided. An example pressure sensing assembly may include: a first member defining an aperture, the aperture comprising an inner opening disposed on an inner surface of the first member and an outer opening disposed on an outer surface of the first member; a protection diaphragm disposed on the inner surface of the first member; and a sensing diaphragm disposed in a second member fastened to the first member.

Systems, methods, and apparatuses provided herein relate to a controller for determining a pressure differential across a fluid filter by receiving inlet pressure data regarding a pressure of the fluid upstream of the filtering element, receiving outlet pressure data regarding a pressure of the fluid downstream of the filtering element, receiving engine speed data regarding a speed of the engine, receiving temperature data regarding a temperature of the fluid, and determining a pressure drop across the filtering element based on the inlet pressure data, the outlet pressure data, the engine speed data, and the temperature data.

The invention provides a combo MEMS device. The combo MEMS device includes a substrate, a device layer, a cap, and at least two sensor units. The device layer is on the substrate. The cap is on the device layer. At least two sensor units which are adjacent to each other are both formed by the substrate, the device layer, and the cap. The first sensor unit includes a sealed space, and the second sensor unit includes a membrane and a semi-sealed space. The membrane is formed by reducing a thickness of a portion of the device layer. The semi-sealed space is formed between the substrate and the device layer or between the device layer and the cap, to receive an external pressure through an external pressure communication opening. The external pressure communication opening is formed between the substrate and the device layer, or between the device layer and the cap, or between the substrate and the cap.

A sensing system that provides an isolation diaphragm through which pressure is transmitted from a process fluid to a fill fluid contained within the sensing system's body is provided. In the system, fill fluid transfers pressure to semiconductor sensors that provide signals for both the differential pressure and the static pressure, thereby allowing for signal conditioning of the differential output to compensate for the effects of static pressure. The system's body provides a cavity for fill fluid behind each of the isolation diaphragms. At least one flat plate actuation diaphragm allows controlled movement of oil as the differential pressure of the isolation diaphragm increases. Fluid volumes are managed for thermal effects, passive thermal volume change; compensation is accomplish by offsetting the large coefficient of thermal expansion (CTE) of fill fluid by providing at least one insert whose coefficient of thermal expansion is smaller than the CTE of the system body.

A pressure measuring cell includes an elastic measuring membrane which is contactable with a first pressure on a first side and with a second pressure on a second side facing away from the first side. The measuring membrane is deflectable as a function of a difference between the first pressure and the second pressure, wherein the measuring membrane pressure-tightly isolates a first volume, which is facing the first side of the measuring membrane, from a second volume, which is facing the second side of the measuring membrane. The pressure measuring cell further includes a transducer for transducing the pressure dependent deflection of the measuring membrane into an electrical or optical signal. The measuring membrane has in the equilibrium state of the measuring membrane compressive stresses at least at the surface of the measuring membrane at least in a radial edge region, in which in the deflected state of the measuring membrane under pressure loading tensile stress maxima occur.

A pressure output device (POD) assembly for sensing fluid pressure in a fluid processing system, is provided. This POD assembly includes a shell defining a shell interior, and a movable diaphragm disposed in the shell interior and separating the shell interior into a flow-through chamber and a pressure sensing side. A sensor port is in fluid communication with the pressure sensing side. An inlet port and an outlet port are in fluid communication with the flow-through chamber. The inlet port and the outlet port define an inlet and an outlet, respectively, of a flow-through channel that passes through the flow-through chamber. A boss protrudes from the interior wall of the shell and extends into the flow-through channel to prevent occlusion of flow under different pressure conditions within the flow-through chamber.

Certain implementations of the disclosed technology may include systems, methods, and sealed transducer assembly with a pressure relief vent. In certain implementations, a transducer assembly is provided having a vent bore and a rupturable membrane sealing the vent bore. The vent bore may extend from an internal portion of the transducer assembly to an external portion of the transducer assembly. The rupturable membrane is configured to maintain a seal within the internal portion of the transducer assembly for a first range of a pressure differential between the internal portion of the transducer assembly and the external portion of the transducer assembly, and rupture and vent pressure through the vent bore when the pressure differential exceeds the first range.

Pressure sensor assemblies comprise a sensor body having a sensing membrane and wherein a fluid is placed in communication with the membrane to determine a fluid pressure. A support is connected with the body and includes an opening for receiving the fluid from an external source, wherein the opening is in fluid-flow communication with the membrane. The pressure sensor comprises one or more elements disposed therein configured to mitigate transmission of a fluid pressure spike to the sensing membrane. The body or the support may have a pressure mitigating element, e.g., an internal channel, for receiving the fluid from the opening and transferring it to the membrane, wherein the channel may itself be configured to provide the desired protection against fluid pressure spikes, or may be connected with another internal element to provide such protection.

A pressure gauge includes a hollow tube, a drive element, an anti-leak spring, a resilient element, and a cap. The hollow tube includes an accommodation chamber, a connector having a conduit, and a display unit. The drive element includes a protection unit, a first open segment, a second distal segment, a receiving portion, a hollow extension, and a protrusion. An anti-leak spring is received in the hollow extension of the drive element and abuts against the protrusion and the protection unit. The resilient element is received in the receiving portion. The cap includes a seat, a push bolt, and multiple passages. The accommodation chamber has a first fixing section and a second fixing section, a diameter of which is different from that of the first fixing section. The hollow tube further includes a tilted surround section and at least one discharge orifice.

The invention relates to a pressure sensor (10) comprising a cavity (12) containing a liquid, said cavity (12) being closed at a first end by a first diaphragm (20a) and at a second end by a second diaphragm (20b), and a measuring body (30) which comprises a strain gauge (31) positioned inside said cavity (12), characterized in that the measuring body (30) is mechanically connected only to one diaphragm among the first diaphragm (20a) and the second diaphragm (20b) by a connection member (50), the measuring body (30) comprising a shape having central symmetry and the connection member (50) being fastened to the center of symmetry of said measuring body (30).