integrated sensor

Abstract

The invention is entitled "Integrated sensor". The invention provides an integrated sensor for detecting a gas present in an environment. The integrated sensor comprises a first gas sensor and a second gas sensor. The first gas sensor is configured to measure a first gas and the second gas sensor is configured to measure a second gas. The first gas is different from the second gas. The first gas sensor is an optical sensor and defines an optical cavity. The second gas sensor is disposed within the optical cavity of the first gas sensor.

Description

TECHNICAL FIELD

[0001] Exemplary embodiments of the present disclosure relate generally to integrated sensors, and more particularly to non-dispersive infrared (NDIR) sensors integrated with hydrogen sensors. BACKGROUND

[0002] Non-dispersive infrared (NDIR) sensors generally include an IR source disposed in an optical cavity of the NDIR sensor, a sample chamber containing a gas sample, and a detector. The detector can include an optical bandpass filter dependent on the target gas to be detected. Radiation emitted by the IR source travels within the region of the optical cavity to be received by the detector. Radiation of a particular wavelength can be absorbed by gas molecules of the target gas. The difference between the amount of radiation emitted by the IR source and the amount of IR radiation received by the detector is measured and is indicative of the IR radiation being absorbed by gas molecules in the air inside the sample chamber.

[0003] Generally, NDIR sensors are preferred over traditional catalytic devices due to the reduced power consumption of the NDIR sensor and the reliability and accuracy of the readings. Additionally, NDIR sensors are low cost and provide stable long-term operation. SUMMARY

[0004] Exemplary embodiments of the present disclosure relate to an integrated sensor for detecting a gas present in an environment. The integrated sensor includes a first gas sensor and a second gas sensor. The first gas sensor is configured to measure a first gas, and the second gas sensor is configured to measure a second gas. The first gas is different from the second gas. The first gas sensor is an optical sensor and defines an optical cavity. The second gas sensor is disposed within the optical cavity of the first gas sensor.

[0005] In one exemplary embodiment, the optical cavity of the first gas sensor includes a region having low optical intensity of radiation when the first gas sensor is operated to measure the first gas.

[0006] In one exemplary embodiment, the first gas sensor includes a printed circuit board assembly (PCBA) that is placed within the region of the optical cavity having low optical intensity, and the second gas sensor is mounted on the PCBA.

[0007] In one exemplary embodiment, the second gas sensor is a hydrogen sensor.

[0008] In one exemplary embodiment, the hydrogen sensor is at least one of a small solid state electrochemical sensor or a metal oxide semiconductor (MOS) sensor.

[0009] In one exemplary embodiment, the first gas sensor is a non-dispersive infrared (NDIR) sensor.

[0010] In an example embodiment, the integrated sensor includes a cylindrical ring and two reflective plates in the optical cavity, where the two reflective plates are arranged on opposite sides of the cylindrical ring.

[0011] In an example embodiment, the integrated sensor includes a housing and a turntable, where the turntable is disposed on a top portion of the housing.

[0012] In some embodiments, the turntable includes a dust cover disposed on a top portion of the turntable.

[0013] In an example embodiment, the turntable further includes an elastomeric seal positioned below the dust cover.

[0014] In some embodiments, a non-dispersive infrared (NDIR) sensor for measuring a first gas and defining an optical cavity includes a printed circuit board assembly (PCBA) disposed within the optical cavity of the NDIR sensor. The PCBA includes a gas sensor mounted on the PCBA, the gas sensor configured to measure a second gas, where the first gas is different than the second gas.

[0015] In an example embodiment, the gas sensor is a hydrogen sensor.

[0016] In an example embodiment, the hydrogen sensor is at least one of a small solid-state electrochemical sensor or a metal oxide semiconductor (MOS) sensor.

[0017] In some embodiments, the optical cavity includes a region having low optical intensity of radiation when the NDIR sensor is operated to measure the first gas.

[0018] In an example embodiment, the PCBA is disposed within the region of the optical cavity having low optical intensity.

[0019] In an example embodiment, the optical cavity is coated with gold.

[0020] In an example embodiment, the NDIR sensor includes a cylindrical ring and two reflective plates in the optical cavity, where the two reflective plates are arranged on opposite sides of the cylindrical ring.

[0021] In an example embodiment, the NDIR sensor includes a housing and a turntable, where the turntable is disposed on a top portion of the housing.

[0022] In some embodiments, the turntable includes a dust cover disposed on a top portion of the turntable.

[0023] In various embodiments, the turntable further includes an elastomeric seal positioned below the dust cover.

[0024] The above summary of the invention is provided for the purpose of summarizing some example embodiments only and to provide a basic understanding of some aspects of the disclosure. Accordingly, it will be appreciated that the above described embodiments are merely examples and should not be construed as limiting the scope or spirit of the disclosure in any way. It will be appreciated that the scope of the disclosure encompasses many potential embodiments, some of which will be further described below, in addition to those here summarized. BRIEF DESCRIPTION OF DRAWINGS

[0025] The description of the illustrative embodiments can be read in conjunction with the accompanying drawings. It will be appreciated that the elements shown in the figures are not necessarily to scale and that the dimensions of some of the elements have been exaggerated relative to other elements for the sake of explanation and clarity. Embodiments consistent with the teachings of the present disclosure are illustrated and described in relation to the figures presented herein, in which:

[0026] Figures 1A-1B A perspective view of an integrated sensor for detecting a gas according to an example embodiment of the present disclosure is shown;

[0027] Figures 2A-2C Various views of an integrated sensor for detecting multiple gases according to an example embodiment of the present disclosure are shown;

[0028] Figure 3 An exploded view of an integrated sensor according to an example embodiment of the present disclosure;

[0029] Figures 4A-4B A spherical ring reflector of an integrated sensor according to an example embodiment of the present disclosure is shown;

[0030] Figure 5 A spherical ring reflector of an integrated sensor according to an example embodiment of the present disclosure is shown;

[0031] Figure 6 Radiation within a spherical ring reflector of an integrated sensor according to an example embodiment of the present disclosure is shown;

[0032] Figure 7 A cylindrical ring of an integrated sensor according to an example embodiment of the present disclosure is shown; and

[0033] Figure 8 A ring reflector and printed circuit board assembly (PCBA) of a non-dispersive infrared (NDIR) sensor according to an example embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0034] Some embodiments of the present disclosure will now be described below by reference to the drawings, which show, by way of illustration, certain embodiments thereof but are not intended to be limiting of the present disclosure solely to the embodiments illustrated and described. In fact, the present disclosure can 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. The terms "or" and "and" are used herein in both the alternative and conjunctive sense, unless otherwise indicated. The terms "exemplary" and "illustrative" are used herein to mean example or illustrative, without quality level indication. Like numbers refer to like elements throughout.

[0035] The components illustrated in the figures represent components that can or can not be present in the various exemplary embodiments of the present disclosure described herein, such that embodiments can include fewer or more components than those shown in the figures without departing from the scope of the present disclosure.

[0036] Turning now to the drawings, the specific embodiments shown in the drawings are intended to describe the various configurations and are not intended to limit the only configurations in which the concepts described herein can be practiced. The detailed description includes specific details to provide a thorough understanding of various concepts, like numbers refer to like elements throughout several views. However, it will be apparent to those of ordinary skill in the art of the present disclosure that the concepts can be practiced without these specific details.

[0037] In contrast to conventional catalytic devices, non-dispersive infrared (NDIR) sensors are increasingly used to provide a primary power consumption reduction. NDIR sensors are unable to detect hydrogen gas (H2) without an infrared signature. Existing sensors require a dedicated external hydrogen sensor to be included in the housing of the main sensor. Incorporating a hydrogen sensor requires a large amount of space within the multi-gas sensor. Such sensors consume power and are not immune to poisoning provided by NDIR sensors. Existing hydrogen electrochemical sensors are not easily integrated with miniature IR gas sensors and require careful design to prevent electrolyte leakage. The process of combining these sensors is complex.

[0038] Various exemplary embodiments described in the present disclosure relate to an integrated sensor, such as an NDIR sensor integrated with a hydrogen sensor for detecting the presence of a gas in an environment. The integrated sensor includes a first gas sensor and a second gas sensor. The first gas sensor, for example, an NDIR sensor, is configured to measure a first gas, and the second gas sensor, such as a hydrogen sensor, is configured to measure a second gas. The first gas is, for example, methane (CH4). In another example, the first gas is carbon dioxide (CO2) or a similar gas, and is different from the second gas, which is hydrogen gas. The first gas sensor defines an optical cavity within which an IR source or emitter and a detector are disposed. The second gas sensor is disposed within the optical cavity of the first gas sensor.

[0039] Details regarding the components of the integrated sensor and the way they work are described in detail with reference to the subsequent drawings and description.

[0040] Figures 1A-1B An integrated sensor 100 with a turret 102 is shown in accordance with an example embodiment of the present disclosure. The integrated sensor 100 includes the turret 102 at a top side 104, an outer housing 106, and a printed circuit board assembly (PCBA) 108 on a bottom side 110. As shown, the turret 102 is a part of the outer housing 106. The turret 102 is a void and, in one example, is used to house a gas filter. The turret 102 includes an optical cavity. In one example, the optical cavity is coated with gold to increase reflectivity. The PCBA 108 includes voltage contacts 112 and 114 and other contacts 116 for electrodes or emitters or receivers. The PCBA 108 also includes sensor circuitry 118 for an NDIR sensor and a second gas sensor 120 disposed on the PCB board. Details of the PCBA 108 and the second gas sensor, such as a hydrogen sensor, are explained in detail with the subsequent drawings.

[0041] Figures 2A-2C Various views of the integrated sensor 100 in accordance with an example embodiment of the present disclosure are shown. Figure 2A A top view 200 is shown, Figure 2B A side view 202 is shown, and Figure 2C A bottom view 204 of the integrated sensor 100 is shown. Figure 2A The turret 102 and the outer housing 106 are shown. The turret 102 includes a dust cover 206. In one example, the dust cover 206 has a circular shape. The shape of the dust cover 206 varies based on the shape of the outer housing 106 and the opening within the outer housing 106 where the dust cover 206 is placed to cover. In one example, the outer housing 106 has a length of 10 millimeters (mm) and the dust cover 206 has a diameter of 12.30 mm.

[0042] In one example, the turret 102 includes an elastomeric seal 208 as shown in Figure 2B The elastomeric seal 208 is placed between the dust cover 206 and the top surface of the outer housing 106. In one example embodiment, the length of the turret 102 is in the range of 17.56 mm - 17.76 mm and the length of the dust cover 206 is 17 mm. In one example embodiment, the height of the outer housing 106 is in the range of 6.85 mm to 7.15 mm. In another example, the height of the integrated sensor 100 including the dust cover 206 is 10.25 mm.

[0043] In one embodiment, PCBA 108 is disposed within an optical cavity and includes sensor circuitry 118 for a first gas sensor, such as an optical sensor. Sensor circuitry 118 is used to determine and measure the concentration of a target gas in the environment. In one example, the optical sensor is a non-dispersive infrared (NDIR) sensor for measuring the first gas, such as methane (CH4). In another example, the first gas is carbon dioxide (CO2). PCBA 108 also includes a second gas sensor 120, such as a hydrogen sensor for detecting a second gas (hydrogen). In one example, the hydrogen sensor can be a small solid-state electrochemical sensor or a metal-oxide-semiconductor (MOS) sensor. The hydrogen sensor can be any other type of sensor that can be used with an NDIR sensor. In one example, the second gas sensor 120 can be any other gas sensor, such as a carbon monoxide (CO) sensor or a volatile organic compound (VOC) sensor.

[0044] Figure 3 An exploded view of an integrated sensor 100 according to an exemplary embodiment of the present disclosure is shown. The integrated sensor 100 includes a dust cover 206, an O-ring 302, and a housing 304 having labels 306-a and 306-b placed on opposite sides of the housing 304. Furthermore, the integrated sensor 100 includes a filler portion 308, a ring optics portion 310, a base optics portion 312, adhesives 314 and 316, and a PCBA 108. The PCBA 108 includes a base PCB and a vertical component or vertical PCB 318.

[0045] like Figure 3 As shown, in the assembled state, the vertical component or vertical PCB 318 passes through the openings of the base optics 312, the annular optics 310, and the filling portion 308. Adhesives 314 and 316 secure the PCBA 108 to the base optics 312. In the assembled state, the PCBA 108 and the vertical PCB 318 are disposed within the optical cavity of the integrated sensor 100. In one exemplary embodiment, a hydrogen sensor is positioned on the PCBA 108. In such embodiments, one or more openings are provided in the base optics 312 and the annular optics 310 to provide electrical connection to the hydrogen sensor. In another exemplary embodiment, the hydrogen sensor is disposed on the vertical PCB 318, referring to... Figure 8 Detailed explanation.

[0046] Now for reference Figures 4A-4Bembodiments, the emitter 402 can be modulated. The spherical ring reflector 400 can also include a detector 404 configured to receive the emitted radiation. In some embodiments, the spherical ring reflector 400 can include a curved wall 410, where a beam path 420 from the emitter 402 can be reflected from the curved wall 410 and directed toward the detector 404. The curved wall 410 can "contain" the beam path 420 within the spherical ring reflector 400, allowing the beam path 420 to be focused toward the detector 404 and preventing continuous expansion of the beam path 420. In Figure 4A and Figure 4B In the illustrated embodiment, the emitter 402 and the detector 404 can be oriented "back-to-back." However, other orientations of the emitter 402 and the detector 404 can also be used.

[0047] In some embodiments, the emitter 402 and the detector 404 can be mounted side-by-side, back-to-back, opposite sides, or in other orientations. The spherical ring reflector 400 itself, and optionally other reflector elements, can be used to direct radiation from the emitter 402 toward the detector 404.

[0048] In use, a gas can be passed through the spherical ring reflector 400 as radiation is directed from the emitter 402 toward the detector 404. In some embodiments, the detector 404 can include one or more filters for a target wavelength and / or a reference wavelength. In some embodiments, the emitter 402 can include one or more filters, and / or multiple filters can be used within the spherical ring reflector 400. Detection of the target wavelength can be related to the presence and / or amount of a target gas within the gas passing through the spherical ring reflector 400. For example, the gas passing through the spherical ring reflector 400 can include a flammable gas, a hydrocarbon, CO, and / or CO2, among others.

[0049] In some embodiments, different methods can be used to expand the beam path 420 from the emitter 402 to the curved wall 410. For example, in Figure 4A a y-axis expansion can be used. As another example, in Figure 4B an x-axis expansion can be used. The expansion method can provide various benefits for control of the beam path 420 within the spherical ring reflector 400.

[0050] Figure 5A spherical ring reflector 500 is shown that includes a central region 502 located within a central region of the spherical ring reflector 500. The central region within the spherical ring reflector 500 can be referred to as a "dead zone" because the beam paths 520 do not pass through this region. The dead zone is a region within the optical cavity where the optical intensity is low or zero. Thus, when a gas passes through the spherical ring reflector 500, the gas passing through the dead zone can not interact with any of the beam paths 520 and can be wasted. In one example embodiment, the PCBA 108 or vertical PCB 318 of the integrated sensor 100 is extended to be positioned within the central region 502 or dead zone to incorporate a hydrogen sensor.

[0051] As shown in FIG. 4, in some embodiments, the curved wall 410 can have certain regions 602 in which radiation is more focused on the surface of the curved wall 410. For example, at the four corners of the beam path 420, the intensity of the radiation can be higher than in other regions of the curved wall 410. In some embodiments, the regions of the curved wall 410 that do not have high intensity radiation can be used for other purposes, such as positioning other elements, electronic components, condensation removal elements, etc. Figure 6

[0052] Figure 7 A cylindrical ring 700 of the integrated sensor 100 according to an example embodiment of the disclosure is shown. In one example, the cylindrical ring 700 is disposed in the housing 304 of the integrated sensor 100. The spherical ring 700 has a cylindrical inner surface. The cylindrical ring 700 includes a ring 702 and two reflective plates 704 and 706. The two reflective plates 704 and 706 are arranged on the top and bottom sides of the ring 702 to reflect light coming out of the ring 702. For example, the reflective plate 704 is positioned on the bottom portion of the ring 702 and the reflective plate 704 is positioned on the top portion of the ring 702. In one example, the height of the cylindrical ring 700 is 1.5 mm to suppress light.

[0053] In one example, the cylindrical ring 700 can be made by resin molding. Resin molding includes molding and coating with a high reflective material such as gold, aluminum with a special filter. A source and detector with a special filter are disposed in the cylindrical ring 700 for spectroscopic absorption analysis and the filter can be changed for various target gases such as carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), sulfur hexafluoride (SF6), sulfur dioxide (SO2), and alcohols. The method of manufacturing the cylindrical ring 700 is cost-effective and increases the signal-to-noise ratio, thereby improving the resolution of the sensor. Furthermore, using such a cylindrical ring 700 increases the average path length and the total efficiency by 18.6% and 35.7%, respectively. These improvements provide enhanced sensitivity and resolution for the NDIR sensor.

[0054] ​Figure 8 A ring reflector 800 utilizing electronic component assembly is shown in accordance with example embodiments of the present disclosure. The ring reflector 800 includes an emitter 802, a detector 804, and a printed circuit board assembly (PCBA) 806 (also referred to as PCBA 108), where a beam path 820 from the emitter 802 is reflected from a curved wall 810 of the ring reflector 800 toward the detector 804. Figure 8 How the beam path 820 can generate more than one focal point at the detector 804 due to the propagation of the beam path 820 is shown. The emitter 802 and the detector 804 can be attached to one or more connectors 808 and 812 configured to allow communication between the emitter 802, the detector 804, and the PCBA 806. As described above, one or more of the connectors 808 and 812 can be located within the central dead zone of the ring reflector 800. In one example, the PCBA 806 includes an extension 814 on a vertical portion or vertical PCB 318 of the PCBA 806 disposed in the central dead zone. The extension 814 is an additional or second gas sensor, such as a hydrogen sensor for detecting the presence of hydrogen in the environment. The positioning of the hydrogen sensor in the central dead zone provides minimal or zero interference to the radiation concentrated on the peripheral region of the optical cavity. The extension 814 is disposed in a manner such that the hydrogen sensor is disposed in a region of the optical cavity having low or zero optical intensity, such that the extension 814 does not impinge on critical portions of the optical path. Such positioning of the hydrogen sensor provides uninterrupted operation of the hydrogen sensor in the case of NDIR sensor operation, thereby enhancing the reliability of the hydrogen sensor.

[0055] The integrated sensor 100 having the first gas sensor (such as the NDIR sensor) and the second gas sensor (such as the hydrogen sensor) in one package allows for a smaller housing and footprint of the integrated sensor 100. The integrated sensor 100 also has low power consumption compared to elements and semiconductors, and enables extended battery life. The integrated sensor 100 reduces design complexity and facilitates accelerated product development.

[0056] It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. In this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as removable storage drive 124, a storage device 126, and a memory 128. These and such

[0057] References in the specification to “one embodiment,” “an embodiment,” “embodiments,” or “one or more embodiments” mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, or to one or more other embodiments. Furthermore, the described features, advantages, characteristics, etc. can be applied to some embodiments and not to others.

[0058] It should be noted that as employed herein the terms “comprises”, “comprising”, and other variations such as “comprising”, “includes”, “including” and related terms are intended to be open-ended terms that specifically permit the presence of one or more other features, elements, integers, steps or components not expressly stated or shown in the claims or description of the application.

[0059] Detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary and can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure. It is to be understood that features and / or variants of the disclosed embodiments can be combined, substituted, or eliminated for additional modifications, enhancements, or other embodiments not specifically described.

[0060] While it is apparent that the exemplary embodiments disclosed herein fulfill the objectives of the present disclosure, it will be appreciated that numerous modifications and other embodiments can be devised by those skilled in the art. Therefore, it is intended that the appended claims be construed to include all such modifications and embodiments.

Claims

1. An integrated sensor comprising: a first gas sensor configured to measure a first gas, wherein the first gas sensor is an optical sensor and the optical sensor defines an optical cavity; and a second gas sensor configured to measure a second gas, the second gas being different from the first gas, wherein the second gas sensor is disposed within the optical cavity of the first gas sensor, wherein the optical cavity of the first gas sensor includes a region having low optical intensity of radiation when the first gas sensor is operated to measure the first gas, and wherein the second gas sensor is positioned within the region of the optical cavity having low optical intensity.

2. The integrated sensor of claim 1, wherein, the first gas sensor includes a printed circuit board assembly (PCBA) that is placed within the region of the optical cavity having low optical intensity, and the second gas sensor is mounted on the PCBA.

3. The integrated sensor of claim 1, wherein, the second gas sensor is a hydrogen sensor.

4. The integrated sensor of claim 3, wherein, the hydrogen sensor is at least one of a small solid-state electrochemical sensor or a metal oxide semiconductor (MOS) sensor.

5. The integrated sensor of claim 1, wherein, the first gas sensor is a non-dispersive infrared (NDIR) sensor.

6. The integrated sensor of claim 1, further comprising a cylindrical ring and two reflective plates in the optical cavity, wherein, the two reflective plates are arranged on opposite sides of the cylindrical ring.

7. The integrated sensor of claim 1, comprising a housing and a turntable, wherein, the turntable is disposed on a top portion of the housing, and the turntable includes a dust cover disposed on a top portion of the turntable, wherein the turntable further includes an elastomeric seal positioned below the dust cover.

8. A non-dispersive infrared (NDIR) sensor for measuring a first gas, wherein, the NDIR sensor defines an optical cavity, the NDIR sensor comprising: a printed circuit board assembly (PCBA) disposed within the optical cavity of the NDIR sensor, wherein the PCBA includes: a gas sensor mounted on the PCBA, the gas sensor configured to measure a second gas, wherein the second gas is different from the first gas, wherein the optical cavity includes a region having low optical intensity of radiation when the NDIR sensor is operated to measure the first gas, and wherein the PCBA is disposed within the region of the optical cavity having low optical intensity.

9. The NDIR sensor of claim 8, wherein, the gas sensor is a hydrogen sensor.

10. The NDIR sensor of claim 8, wherein, the optical cavity is coated with gold.

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