Preformed solids as a coupling mechanism in media-isolated pressure sensors.

Abstract

To provide a mechanism for easily and reliably coupling external pressure and / or force from measured media to a pressure sensing circuit of a media-isolated pressure sensor.SOLUTION: A media-isolated pressure and force sensor is provided utilizing a deformable solid as a coupling mechanism for transmitting a received external pressure to a surface of a pressure sensing diaphragm. An example media-isolated pressure and force sensor may include a pressure sensing diaphragm that is coupled to a substrate of the media-isolated pressure sensor, and a deformable solid. The deformable solid may be configured to deform to substantially cover a sensing surface of the pressure sensing diaphragm to create a barrier between the pressure sensing diaphragm and measured media. In addition, the deformable solid may fluidly couple the measured media to the pressure sensing diaphragm such that in an instance in which a force is applied to the deformable solid by the measured media the force is transmitted to the pressure sensing diaphragm.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to pressure and force sensors, and more particularly to media-isolated pressure and / or force sensors. Summary of the Invention [Problem to be solved by the invention]

[0002] Applicant has identified many technical challenges and difficulties associated with coupling mechanisms in media-isolated pressure and force sensors. Through applied hard work, ingenuity, and innovation, Applicant has solved the problems associated with coupling mechanisms in media-isolated pressure and force sensors by developing the solutions embodied in this disclosure, which are described in detail below.

[0003] Various embodiments are directed to exemplary mechanisms for easily and reliably coupling external pressure and / or force from the medium being measured to the pressure sensing circuitry of a media-isolated pressure sensor.

[0004] According to some embodiments of the present disclosure, an exemplary media-isolated pressure sensor utilizing a deformable solid as a coupling device is provided. In some embodiments, the media-isolated pressure sensor may include a pressure-sensing diaphragm coupled to a substrate of the media-isolated pressure sensor and a deformable solid. The deformable solid may be configured to deform to substantially cover a sensing surface of the pressure-sensing diaphragm to create a barrier between the pressure-sensing diaphragm and the medium to be measured. Additionally, the deformable solid may fluidly couple the medium to be measured to the pressure-sensing diaphragm such that when a force is applied to the deformable solid by the medium to be measured, the force is transferred to the pressure-sensing diaphragm.

[0005] In some embodiments, the media-isolated pressure sensor may further comprise a pressure-sensing die electrically connected to the pressure-sensing diaphragm.

[0006] In some embodiments, the pressure sensing diaphragm may be disposed on the pressure sensing die opposite the substrate.

[0007] In some embodiments, the media-isolated pressure sensor may further comprise a ring seal assembly protruding from the substrate and defining a pressure-sensing cavity, the ring seal assembly forming a surrounding perimeter around the pressure-sensing die, the ring seal assembly extending from the substrate beyond the furthest extent of the pressure-sensing diaphragm.

[0008] In some embodiments, the pressure sensing die can indicate the amount of force applied by the medium being measured based on the deflection of the pressure sensing diaphragm.

[0009] In some embodiments, the pressure sensing diaphragm may further comprise a piezoresistive sensor arranged in a Wheatstone bridge circuit, and the magnitude of the force exerted by the medium to be measured may be determined based on one or more output signals of the Wheatstone bridge circuit.

[0010] In some embodiments, the deformable solid may further deform to substantially fill the pressure sensitive cavity.

[0011] In some embodiments, the pressure sensing diaphragm may be fluidly isolated from the medium being measured.

[0012] In some embodiments, the ring seal assembly may include an inner periphery and an outer periphery, the inner periphery being circular.

[0013] In some embodiments, the maximum cross-sectional diameter of the deformable solid may be equal to or greater than the diameter of the inner circumference of the ring seal assembly.

[0014] In some embodiments, the deformable solid may be manufactured to be free of defects that would change its fluid binding properties over time.

[0015] In some embodiments, the medium to be measured may be a fluid.

[0016] Further included is another exemplary media-isolated pressure sensor that utilizes a deformable solid as a coupling device. In some embodiments, the exemplary media-isolated pressure sensor may include a pressure sensing circuit that includes a pressure-sensing diaphragm attached to a substrate of the media-isolated pressure sensor and disposed over a pressure-sensing die. Additionally, the media-isolated pressure sensor may include a ring seal assembly that protrudes from the substrate and defines a pressure-sensing cavity, the ring seal assembly extending from the substrate beyond the furthest extent of the pressure-sensing diaphragm and forming a perimeter surrounding the pressure-sensing die. Furthermore, the media-isolated pressure sensor may include a coupling mechanism that includes a deformable solid that deforms to cover a sensing surface of the pressure-sensing diaphragm, the deformable solid fluidly coupling the medium to be measured to the pressure-sensing diaphragm such that when a force is applied to the deformable solid by the medium to be measured, the force is transferred to the pressure-sensing diaphragm.

[0017] In some embodiments, the media-isolated pressure sensor may further comprise a vent in the substrate fluidly connecting the pressure sensing cavity with the environment opposite the surface of the pressure sensing cavity.

[0018] In some embodiments, the substrate may be a printed circuit board.

[0019] In some embodiments, the pressure sensing die may be electrically connected to the printed circuit board using one or more through-hole connections.

[0020] In some embodiments, at least one of the one or more through-hole connections may fluidly connect the pressure sensing cavity with an environment on the opposite side of the substrate from the pressure sensing cavity.

[0021] In some embodiments, the pressure sensing die may indicate the magnitude of the force applied by the medium being measured based at least in part on the deflection of the pressure sensing diaphragm.

[0022] In some embodiments, the pressure sensing diaphragm may further comprise a piezoresistive sensor arranged in a Wheatstone bridge circuit, and the magnitude of the force exerted by the medium to be measured may be determined based on one or more output signals of the Wheatstone bridge circuit.

[0023] Further included are exemplary coupling mechanisms for media-isolated pressure sensors. In some embodiments, the coupling mechanism may comprise a deformable solid configured to deform to substantially cover a sensing surface of the pressure-sensing diaphragm to create a barrier between the pressure-sensing diaphragm and the medium to be measured. Additionally, the deformable solid may fluidly couple the medium to be measured to the pressure-sensing diaphragm such that when a force is applied to the deformable solid by the medium to be measured, the force is transferred to the pressure-sensing diaphragm. [Brief explanation of the drawings]

[0024] Reference will now be made to the accompanying drawings, in which components illustrated in the figures may or may not be present in a particular embodiment described herein. Some embodiments may include fewer (or more) components than shown in the figures according to exemplary embodiments of the present disclosure. [Figure 1] FIG. 1 illustrates a perspective view of an exemplary media-isolated pressure sensor and a deformable solid body, according to an exemplary embodiment of the present disclosure. [Figure 2] FIG. 2 illustrates a cross-sectional view of an exemplary media-isolated pressure sensor, according to an exemplary embodiment of the present disclosure. [Figure 3] FIG. 3 illustrates a cross-sectional view of an exemplary deformable solid superimposed on a cross-sectional view of an exemplary media-isolated pressure sensor, according to an exemplary embodiment of the present disclosure. [Figure 4] FIG. 4 illustrates a cross-sectional view of an exemplary media-isolated pressure sensor positioned to determine a pressure reading associated with a measured medium, according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0025] Exemplary embodiments are described in more detail below with reference to the accompanying drawings, which show some, but not all, embodiments of the invention of this disclosure. Indeed, embodiments of the disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.

[0026] Various illustrative embodiments address technical issues associated with coupling external pressure or force from a medium to be measured to a pressure sensing circuit in a media-isolated pressure sensor. As will be appreciated by those skilled in the art to which this disclosure pertains, there are numerous scenarios in which pressure and / or force may be measured while maintaining isolation between the pressure sensing circuit (e.g., a pressure sensing die) and the medium to be measured (e.g., a fluid) generating the pressure. For example, a medical professional may need to measure a patient's blood pressure through an intravenous line. In such a scenario, it is important that the pressure sensing die and other circuitry remain isolated from the patient's bodily fluids and incoming intravenous fluids so as to remain compliant with medical standards. Additionally, there is a high demand for media-isolated pressure sensors suitable for measuring pressure in a fluid medium that can be manufactured at low cost. Therefore, a low-cost mechanism is needed to transmit the pressure of a medium to be measured (e.g., a bodily fluid) to a pressure sensing die while maintaining a barrier between the bodily fluid and the pressure sensing die.

[0027] Current coupling mechanisms have many drawbacks. For example, pressure sensors manufactured using gel as a coupling device are time-consuming to manufacture, and imperfections in the manufacturing process often lead to inaccurate pressure readings. These gel-based coupling devices require a time-consuming process to ensure that there are no air pockets or other irregularities in the gel before calibration can occur. To allow sufficient time for all irregularities to be removed from the gel, a substance must be added to the gel to prevent it from curing too quickly. Once the irregularities are removed and the gel is in place, the gel may need to be manually cured before calibration. In some cases, inhibitors to the curing process continue to operate after manual curing and calibration have occurred, changing the transmission characteristics of the gel over time and causing the pressure reading output to change over time. Additionally, other media-isolated pressure sensors utilize rigid devices as coupling mechanisms that contact the pressure-sensing diaphragm over a small surface area. These rigid coupling mechanisms often cause the pressure-sensing diaphragm to deflect under pressure, again resulting in inaccuracies in the pressure reading output. Finally, some media isolated sensors utilize sealed liquids or oils to act as the coupling mechanism. These devices can be prohibitively expensive to manufacture for many desired applications.

[0028] Various exemplary embodiments described herein utilize various techniques to provide consistent pressure readings after calibration and reduce manufacturing costs for media-isolated pressure sensors. For example, in some embodiments, a deformable solid or plug may be used as the coupling device. Exemplary deformable solids may be manufactured free of air bubbles and other irregularities that can cause shifts or changes in pressure readings over time. Furthermore, utilizing a deformable solid may, in some instances, eliminate the need to harden the coupling mechanism, further simplifying the manufacturing process and reducing the risk of changing coupling characteristics. Additionally, the deformable solid may deform to contact the entire surface of the pressure-sensing diaphragm, resulting in a uniform distribution of transmitted pressure across the surface of the diaphragm. Such uniform contact with the sensing surface of the diaphragm results in an output voltage that varies linearly with applied pressure, providing a closer representation of the applied pressure of the medium than when the coupling force is concentrated in a small area on the surface of the diaphragm. Finally, the malleability of the deformable solid as a coupling mechanism allows the silicone or other material to substantially fill the ring seal assembly, isolating the medium being measured from the pressure sensing diaphragm and other pressure sensing circuitry.

[0029] As a result of the exemplary embodiments described herein, the simplicity in manufacturing media-isolated pressure sensors may be greatly improved. Additionally, media-isolated pressure sensors utilizing a deformable solid as a coupling device may maintain higher accuracy over time.

[0030] FIG. 1 illustrates a perspective view of an exemplary media-isolating pressure sensor 100 and a deformable solid 104. As depicted in the exemplary embodiment of FIG. 1, the media-isolating pressure sensor 100 includes a ring seal assembly 102 mounted on a substrate (e.g., a printed circuit board (PCB) 106). The depicted ring seal assembly 102 forms a ring structure protruding from a surface of the substrate (e.g., PCB 106) and further includes a seal structure 108 surrounding an outer surface at or near the top of the ring seal assembly 102 to create a seal between the ring seal assembly 102 and a fluid conduit 430 (as shown in FIG. 4). The depicted media-isolating pressure sensor 100 further includes a deformable solid 104 (as shown in FIGS. 2-4) that, when inserted within the interior of the ring seal assembly 102, substantially fills the volume of the ring seal assembly 102 and forms a coupling mechanism between the medium to be measured and the pressure sensing circuitry. The example media-isolated pressure sensor 100 of FIG. 1 further depicts a processing element 110 disposed on the PCB 106 and communicatively connected to the pressure sensing circuitry of the media-isolated pressure sensor 100.

[0031] As illustrated in FIG. 1 , a ring seal assembly 102 may be part of a media isolating pressure sensor 100 as described herein. As illustrated in FIG. 1 , the ring seal assembly 102 includes at least one ring seal sidewall 112 and a seal structure 108 surrounding an outer surface of the at least one ring seal sidewall 112 to create a seal between the media isolating pressure sensor 100 and a fluid conduit (e.g., a fluid conduit 430 containing a fluid for pressure measurement). The at least one ring seal sidewall 112 defines an at least substantially smooth inner surface of the ring seal assembly 102 surrounding an interior of the at least one ring seal sidewall 112 and an at least substantially smooth outer surface of the ring seal assembly 102 surrounding an exterior of the ring seal assembly 102. When configured as part of a pressure sensor, the structure of the ring seal assembly 102 is configured to enclose a pressure sensing element within the interior of the ring seal assembly 102 surrounded by the at least one ring seal sidewall 112. 1, the ring seal assembly 102 may have a circular tubular shape (characterized by a diameter and a length), although other configurations may be suitable for particular implementations. For example, the ring seal assembly 102 may have a rectangular cross-section (having four ring seal sidewalls 112), a triangular cross-section (having three ring seal sidewalls 112), a hexagonal cross-section (having six ring seal sidewalls 112), etc.

[0032] The sidewalls of the ring seal assembly 102 may comprise a molded plastic material (e.g., polysulfone, polycarbonate, acrylic, stainless steel, etc.), although it should be understood that in certain embodiments, other materials such as Teflon, glass, etc. may be used. Embodying at least one ring seal sidewall 112 of the ring seal assembly 102 as a molded plastic ring has the advantages of low material costs and ease of manufacture.

[0033] As further illustrated in FIG. 1 , the deformable solid 104 may be part of the media-isolating pressure sensor 100 as described herein. The deformable solid 104, as illustrated in FIG. 1 , is a flawless volume of incompressible material shaped to substantially conform to the cross-sectional shape of the inner surface of the ring seal assembly 102. The deformable solid 104 may be disposed within the hollow interior of the ring seal assembly 102 as an incompressible fluid to provide a fluid coupling mechanism between the medium to be measured and the pressure sensing circuitry, as further described in connection with FIG. 4 . The deformable solid 104 may be pre-fabricated such that all or substantially all air pockets and / or other irregularities are removed from the body of material. As shown in FIG. 1 , the deformable solid 104 may have a spherical shape, although other configurations may be suitable for particular implementations. For example, the deformable solid 104 may have a cylindrical shape, a spheroid shape, a triangular prism shape, a cubic or rectangular prism shape, a hexagonal prism shape, and / or similar shapes. The coupling mechanism embodied by the deformable solid 104 may be composed of any incompressible fluid material, such as silicone, capable of providing a fluid coupling between the medium to be measured and the pressure sensing circuit. Additionally, the coupling mechanism embodied by the deformable solid 104 may be capable of deforming to conform to the shape defined by the interior of the ring seal assembly 102 so that the medium to be measured is isolated from the pressure sensing circuit. Embedding the coupling mechanism as a pre-fabricated, flawless body has the advantage of simple assembly, as the deformable solid 104 does not require a process and subsequent curing time to remove unwanted air pockets. Additionally, a media-isolating pressure sensor 100 utilizing the deformable solid 104 as a coupling mechanism provides more consistent pressure readings after calibration because the properties of the deformable solid 104 do not change over time due to a long-term curing process, and the deformable solid 104 applies a uniformly distributed pressure across the surface of the pressure sensing circuit.

[0034] FIG. 2 illustrates a cross-sectional view of an exemplary media-isolated pressure sensor 100. As shown in the exemplary embodiment of FIG. 2, the media-isolated pressure sensor 100 includes a ring seal assembly 102 mounted to a PCB 106 and defining at least one ring seal sidewall 112. The inner wall of the ring seal sidewall 112 defines a perimeter surrounding a pressure-sensing circuit (e.g., a pressure-sensing diaphragm 216 and a pressure-sensing die 218). The pressure-sensing die 218 is mounted to the PCB 106 at one end, and the pressure-sensing diaphragm 216 is disposed at the opposite end. Additionally, a through-hole conduit 220 defines an opening through the PCB 106, allowing a reference pressure of the environment 234 to interact with the bottom surface of the pressure-sensing diaphragm 216. FIG. 2 further depicts a passageway 224 through the wall of the pressure-sensing die 218, allowing the pressure-sensing diaphragm to be electrically connected to the PCB 106 in a protected manner. The through-hole conduit 220 also, in combination with the passageway 224, provides fluid communication between the pressure sensing cavity 214 and an environment 234 on the opposite side of the PCB 106 when the opening to the pressure sensing cavity 214 defined by the ring seal assembly 102 is blocked by the coupling device. Additionally, the processing element 110 is communicatively connected to the pressure sensing die 218 via electrical connections defined on the PCB 106.

[0035] As illustrated in FIG. 2 , a pressure sensing die 218 may be part of an exemplary media-isolated pressure sensor 100 as described herein. As shown in FIG. 2 , the pressure sensing die 218 comprises a semiconductor material that protrudes from a surface of the PCB 106 and includes at least one sidewall that forms a perimeter around an internal opening. As shown in FIG. 2 , the pressure sensing die 218 may define a rectangular cross-sectional perimeter (characterized by a length and a width) with an opening in its center, although other solutions may be suitable for certain implementations, such as a pressure sensing die 218 having one sidewall that forms a circular cross-sectional perimeter. The illustrated pressure sensing die 218 is attached to the PCB 106 at one end, while the distal end protrudes into the pressure sensing cavity, defining a space inside the perimeter formed by the pressure sensing die 218.

[0036] The pressure-sensing diaphragm 216, also depicted in FIG. 2 , is formed to allow the pressure-sensing diaphragm 216 to rest on the pressure-sensing die 218. In some embodiments, the top surface of the pressure-sensing die 218 may be etched to form recessed features that allow the pressure-sensing diaphragm 216 to fit securely within the confines of the etched features. The pressure-sensing diaphragm 216 as depicted is formed of a semiconductor material. The pressure-sensing diaphragm 216 may include piezoresistive sensors arranged in a Wheatstone bridge circuit, such that pressure and deflection on the pressure-sensing diaphragm 216 create a change in the resistance of the disposed sensors and a voltage output that correlates to the applied force. In the depicted example, the pressure-sensing diaphragm 216 is disposed on at least one sidewall, such that a substantial portion of the pressure-sensing diaphragm 216 is suspended above the interior space created by the pressure-sensing die 218. Positioning the pressure sensing diaphragm 216 over the opening allows the pressure sensing diaphragm 216 to deflect in a manner such that a change in the electrical characteristics of the pressure sensing diaphragm 216 is indicative of the applied pressure. The pressure sensing die 218 also acts to elevate the pressure sensing diaphragm 216 above the surface of the PCB 106, isolating the pressure sensing die 218 from other pressures or vibrations that may interfere with the pressure reading. The pressure sensing diaphragm is electrically connected to the PCB 106 via a through-hole connector 222 that passes through a passage 224 in the pressure sensing die 218, such that an output signal resulting from pressure applied to the pressure sensing diaphragm 216 is transmitted from the pressure sensing die 218 through connections made on the PCB 106 to the processing element 110 to determine the pressure reading. By routing the through-hole connector 222 through the passage 224 to the PCB 106 and making the electrical connection outside of the pressure sensing cavity 214, the electrical connections and soldered components of the pressure sensing die 218 may be protected from damage or shorting by the inserted deformable solid body 104. Additionally, the through-hole conduit 220 provides a fluid connection between the pressure sensing cavity 214 and the environment 234 outside of the pressure sensing cavity 214.Such a configuration allows air to escape through the through-hole conduits 220 when the deformable solid 104 is inserted into the pressure-sensing cavity 214, preventing the creation of trapped air pockets.

[0037] As further illustrated in FIG. 2, the exemplary media-isolated pressure sensor 100 may also include a through-hole conduit 220. As shown in FIG. 2, the through-hole conduit 220 defines an opening in a substrate (e.g., PCB 106) to allow a reference pressure of the environment 234 to interact with a bottom surface of the sensing die 218 and electrically connect to the PCB 106 on an opposite surface of the pressure sensing die 218 using a through-hole connector 222. As shown in FIG. 2, the pressure sensing die 218 may be centered such that an internal opening of the pressure sensing die 218 is aligned with the through-hole conduit 220 to facilitate interaction of the reference pressure from the environment 234 with the bottom of the pressure sensing diaphragm. In some embodiments, the pressure sensing die 218 may be mounted to allow fluid connectivity from within the pressure sensing cavity 214 into the through-hole conduit 220.

[0038] As further illustrated in FIG. 2 , the exemplary media-isolated pressure sensor 100 may also include a processing element 110. In some embodiments, the processing element 110 may be configured to receive an output signal from the pressure sensing die 218 and convert the output signal into a pressure reading. In some embodiments, the processing element 110 may output the pressure reading in analog format, while in other embodiments, the processing element 110 may output the pressure reading in digital format. The processing element 110 may also be utilized to calibrate and equilibrate the piezoresistive sensor prior to distribution of the exemplary media-isolated pressure sensor 100. In some embodiments, the processing element 110 may comprise a processor, a specially configured field programmable gate array (FPGA), a specially programmed application specific integrated circuit (ASIC), a trimmable film resistor network, or other similar computing device. Subsequent pressure readings may be determined based on this calibration.

[0039] 3 illustrates a cross-sectional view of an exemplary deformable solid 104 overlaid on a cross-sectional view of an exemplary media-isolated pressure sensor 100. As depicted in the exemplary embodiment of FIG. 3, the maximum cross-sectional diameter 326 of the deformable solid 104 is greater than the diameter of the inner perimeter 324 of the pressure sensing cavity 214.

[0040] 3 , the exemplary media isolating pressure sensor 100 illustrates an exemplary relative size of the deformable solid 104 compared to the ring seal assembly 102. As shown in the depicted embodiment, the maximum cross-sectional diameter 326 of the deformable solid 104 is larger than the diameter of the inner periphery 324 of the ring seal assembly 102. Although the depicted deformable solid 104 defines a maximum cross-sectional diameter 326 that is larger than the diameter of the inner periphery 324 of the pressure sensing cavity 214, in some embodiments, the maximum cross-sectional diameter 326 of the deformable solid 104 may be equal to or smaller than the diameter of the inner periphery 324 of the pressure sensing cavity 214. If the maximum cross-sectional diameter 326 of the deformable solid 104 is smaller than the diameter of the inner periphery 324 of the pressure sensing cavity 214, the deformable solid 104 must have sufficient volume so that when the deformable solid 104 is forced into the pressure sensing cavity 214, the deformable solid 104 deforms to occupy the entire cross-sectional area of the pressure sensing cavity 214, thereby fluidically isolating the pressure sensing circuit from the medium being measured. In other words, fluid from the medium being measured cannot penetrate the barrier created by the deformable solid 104 between the medium being measured and the pressure sensing circuit. In some embodiments, the maximum cross-sectional diameter 326 of the deformable solid 104 may be 1 to 5 millimeters, more preferably 1.5 to 3.3 millimeters, and most preferably 2 to 2.8 millimeters. In some embodiments, the diameter of the inner periphery 324 of the pressure sensing cavity 214 may be 1 to 4 millimeters, more preferably 1.5 to 3 millimeters, and most preferably 1.75 to 2.25 millimeters. A typical durometer of the deformable solid 104 may be 0 to 20 on the Shore 00 scale, more preferably less than 15 on the Shore 00 scale, and most preferably less than 10 on the Shore 00 scale. However, higher durometer materials may be used if the shape of the deformable solid 104 substantially matches the volume of the pressure sensing cavity 214.

[0041] 4 illustrates a cross-sectional view of an exemplary media-isolating pressure sensor 100 positioned to determine a pressure reading associated with a fluid 428, according to an exemplary embodiment of the present disclosure. As depicted in the exemplary embodiment of FIG. 4, a seal structure 108 surrounds an outer surface proximate an upper end of a ring seal assembly 102. The upper end of the ring seal assembly 102 is inserted into an opening in a fluid conduit 430 carrying a medium to be measured (e.g., fluid 428). The seal structure 108 creates a seal between an opening 432 in the fluid conduit 430 and the media-isolating pressure sensor 100 such that the fluid 428 remains within the fluid conduit 430 and interacts with a deformable solid 104 positioned within the pressure-sensing cavity 214 of the ring seal assembly 102.

[0042] As depicted in FIG. 4 , media isolation pressure sensor 100 may be inserted into an opening 432 of a fluid conduit 430 to determine the pressure of a contained medium to be measured (e.g., fluid 428). While the conduit whose pressure is measured in FIG. 4 is a fluid conduit 430, the pressure of the medium to be measured may be measured in any conduit, tube, cavity, enclosure, or other space. As shown in FIG. 4 , in some embodiments, fluid conduit 430 may include an opening 432 that is substantially identical in size to seal structure 108, such that a fluid-tight seal may be created between opening 432 and the top of ring seal assembly 102 to prevent undesired fluid leakage around the exterior of seal structure 108. Non-limiting examples of fluid conduit 430 include an intravenous line, a catheter, a fluid container, etc.

[0043] As further depicted in FIG. 4 , the exemplary media isolating pressure sensor 100 may include a seal structure 108 that surrounds an outer surface of at least one ring seal sidewall 112 of the ring seal assembly 102 proximate an upper end of the ring seal assembly 102 (e.g., closer to the upper end of the ring seal assembly 102 than to the opposite lower end of the ring seal assembly 102) and forms a protruding barrier between the upper end of the ring seal assembly 102 and the lower end of the ring seal assembly 102. In certain embodiments, the seal structure 108 comprises a resilient material configured to form a fluid seal with at least a substantially smooth surface of the fluid conduit 430. For example, the seal structure 108 may comprise rubber, silicone, or other resilient polymer material. In some embodiments, the ring seal assembly 102 may be directly coupled to the fluid conduit 430 without the aid of the seal structure 108.

[0044] 4 further depicts the deformable solid 104 being inserted into the pressure sensing cavity 214 of the ring seal assembly 102 and deformed to substantially fill the pressure sensing cavity 214. As described in connection with FIG. 3, due to the deformable and incompressible nature of the deformable solid 104, applying a force to insert the deformable solid 104 into the pressure sensing cavity 214 may cause the deformable solid 104 to deform, such that the volume of the deformable solid 104 substantially fills the pressure sensing cavity 214. In addition to substantially filling the pressure sensing cavity 214, FIG. 4 further depicts the deformable solid 104 deforming to form a barrier between the pressure sensing circuit and the medium to be measured (e.g., fluid 428). Furthermore, when the deformable solid 104 is forced into the pressure sensing cavity 214 formed by the ring seal assembly 102 and pressed against the pressure sensing diaphragm 216, the deformable solid 104 deforms to substantially cover the sensing surface of the pressure sensing diaphragm 216. By deforming the coupling mechanism (e.g., the deformable solid 104) to substantially cover the sensing surface of the pressure sensing diaphragm 216, pressure from the medium to be measured (e.g., the fluid 428) may be transmitted uniformly across the sensing surface of the pressure sensing diaphragm 216. The uniform transmission across the entire sensing surface of the pressure sensing diaphragm 216 provides a uniform stretch of the pressure sensing diaphragm 216, which produces an output voltage that varies linearly with the pressure applied to the medium, providing a closer representation of the applied pressure on the medium than when the coupling force is concentrated in a small region on the surface of the diaphragm. Furthermore, by substantially filling the pressure sensing cavity 214, the deformable solid 104 fluidly couples the medium to be measured (e.g., fluid 428) to the pressure sensing circuit (e.g., pressure sensing diaphragm 216 and pressure sensing die 218); in other words, the deformable solid 104 provides a fluid pressure transmission medium and transmits the received external pressure to the surface of the pressure sensing diaphragm 216.

[0045] 4 further depicts cavity vent 434 that allows air and other fluids and / or gases to escape from pressure sensing cavity 214, through PCB 106, and from ring seal assembly 102 into environment 234 on the opposite side of PCB 106. In some embodiments, where pressure sensing die 218 is attached to a substrate (e.g., PCB 106), the attachment mechanism may define a gap (e.g., cavity vent 434) between the bottom surface of pressure sensing die 218 and the surface of the substrate. Such a gap may provide cavity vent 434 from pressure sensing cavity 214, through the defined gap, through through-hole conduit 220, and to the environment 234 on the opposite side of PCB 106. By defining a cavity vent 434 from the pressure sensing cavity 214 to the environment 234 outside the pressure sensing cavity 214, air may escape through the cavity vent 434 when the deformable solid 104 is forced into the pressure sensing cavity 214. Allowing air to escape through the cavity vent 434 prevents problematic air bubbles from lodge on or above the pressure sensing diaphragm 216 and potentially causing unreliable pressure readings.

[0046] Many modifications and other embodiments of the inventions described herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. While the drawings illustrate only certain components of the apparatus described herein, it will be understood that various other components may be used in conjunction with the system. It is understood, therefore, that the invention is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. For example, while primarily described as a media-isolating pressure sensor, those skilled in the art will understand that a media-isolating pressure sensor such as the one described above may also measure forces applied to a coupling mechanism and other forces resulting from a measured medium interacting with the coupling mechanism.

[0047] Although various embodiments according to the principles disclosed herein have been shown and described above, modifications thereof can be made by those skilled in the art without departing from the spirit and teachings of the present disclosure. The embodiments described herein are merely representative and are not intended to be limiting. Many variations, combinations, and modifications are possible and fall within the scope of the present disclosure. Alternative embodiments resulting from combining, integrating, and / or omitting features of the embodiments are also within the scope of the present disclosure. Therefore, the scope of protection is not limited by the description set forth above.

[0048] The use of broader terms such as "comprises," "includes," and "having" should be understood to provide support for narrower terms such as "consisting of," "consisting essentially of," and "comprised substantially of." The use of terms such as "optionally," "may," "might," and "possibly" with respect to any element of an embodiment means that the element is not required, or that the element is alternatively required, with both options being within the scope of the embodiment. Additionally, references to examples are provided merely for illustrative purposes and are not intended to be exhaustive. <Additional Notes> [Form 1] 1. A media-isolated pressure sensor comprising: a pressure sensing diaphragm coupled to a substrate of the media-isolated pressure sensor; a deformable solid body; the deformable solid body is configured to deform to substantially cover a sensing surface of the pressure sensing diaphragm to create a barrier between the pressure sensing diaphragm and a medium to be measured; 1. A media-isolated pressure sensor, wherein the deformable solid fluidly couples the medium to be measured to the pressure-sensing diaphragm such that when a force is applied to the deformable solid by the medium to be measured, the force is transmitted to the pressure-sensing diaphragm. [Form 2] a pressure sensing die electrically connected to the pressure sensing diaphragm; a ring seal assembly protruding from the substrate and defining a pressure sensing cavity; the ring seal assembly forms an enclosing perimeter around the pressure sensing die; the ring seal assembly extends from the substrate beyond a furthest extent of the pressure sensing diaphragm; the pressure sensing diaphragm further comprises a piezoresistive sensor arranged in a Wheatstone bridge circuit, and the magnitude of the force exerted by the measured medium is determined based on one or more output signals of the Wheatstone bridge circuit; 10. The media-isolated pressure sensor of claim 1, wherein the pressure-sensing diaphragm is fluidly isolated from the medium being measured. [Form 3] 10. The media-isolated pressure sensor of claim 1, wherein the deformable solid further deforms to substantially fill the pressure-sensing cavity.

Claims

1. 1. A media-isolated pressure sensor comprising: a pressure sensing diaphragm coupled to a substrate of the media-isolated pressure sensor; A deformable solid body, the deformable solid body is spherical in shape and is configured to deform to substantially cover a sensing surface of the pressure sensing diaphragm to create a barrier between the pressure sensing diaphragm and a medium to be measured; a deformable solid fluidly coupling the medium to be measured to the pressure sensing diaphragm such that when a force is applied to the deformable solid by the medium to be measured, the force is transmitted to the pressure sensing diaphragm; and a pressure sensing die defining a passageway through a wall of the pressure sensing die, the passageway enabling the pressure sensing diaphragm to be electrically connected to the substrate; 1. A media-isolated pressure sensor comprising:

2. a ring seal assembly protruding from the substrate and defining a pressure sensing cavity; the ring seal assembly forms an enclosing perimeter around the pressure sensing die; the ring seal assembly extends from the substrate beyond a furthest extent of the pressure sensing diaphragm; the pressure sensing die is electrically connected to the pressure sensing diaphragm; the pressure sensing diaphragm further comprises a piezoresistive sensor arranged in a Wheatstone bridge circuit, and the magnitude of the force exerted by the measured medium is determined based on one or more output signals of the Wheatstone bridge circuit; 10. The media-isolated pressure sensor of claim 1, wherein the pressure-sensing diaphragm is fluidly isolated from the medium being measured.

3. The media-isolated pressure sensor of claim 1 , wherein the deformable solid further deforms to substantially fill the pressure-sensing cavity.

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