Gas sensor assembly and method for detecting obstacle of gas sensor assembly

Abstract

The invention discloses a gas sensor assembly and a method for detecting an obstacle of a gas sensor assembly. A sensor assembly is used to detect and / or monitor a condition (e.g., the presence and / or accumulation of gas) in a working environment (i.e., a sensing environment). The sensor assembly is operable to determine whether the sensor assembly is operating efficiently, inefficiently, or completely inoperative due to the sensor assembly detecting element being partially blocked, substantially blocked, or completely blocked relative to the sensing environment.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 673,918, filed July 22, 2024. The entire disclosure of the above application is incorporated herein by reference. Technical Field

[0003] This disclosure generally relates to gas sensor assemblies, systems and methods for operating gas sensor assemblies, and more specifically to gas sensor assemblies and methods for determining whether the performance of a gas sensor assembly is degraded due to an obstacle between the sensor and the operating environment. Background Technology

[0004] Hydrocarbon-based refrigerants have been used as working fluids in heat pumps and refrigeration cycles of conventional air conditioning and refrigeration systems. In the 20th century, fluorocarbons such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs) became prevalent in air conditioning and refrigeration systems due to their favorable thermodynamic properties, non-flammability, and non-toxicity. However, while the inert nature of many CFCs and HCFCs made them the preferred refrigerants in air conditioning and refrigeration systems for many years, this same inertness resulted in their long atmospheric lifespans. Following the discovery of the ozone hole in the stratosphere in polar regions in the early 1980s, air conditioning and refrigeration systems transitioned to ozone-free HFC refrigerants such as R-134a, R-143a, and R-410A. In the early 21st century, new refrigerants with even greater environmental safety were developed. These new refrigerants are often referred to as low global warming potential (GWP) refrigerants.

[0005] The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) has published standards for classifying various refrigerants based on their toxicity and flammability. For example, ASHRAE Standard 34 classifies refrigerants with lower toxicity as Class A refrigerants and those with higher toxicity as Class B refrigerants. The flammability classification of refrigerants is determined according to ASTM E681, Standard Test Method for Flammability Concentration Limits of Chemicals (Vapor and Gas), at a temperature of 60°C and a pressure of 101 kPa. According to ASHRAE Standard 34, Class 1 refrigerants do not propagate flame, Class 2L refrigerants have lower flammability and slow flame propagation (e.g., a burning rate less than 10 cm / s), Class 2 refrigerants have lower flammability and faster flame propagation (e.g., a burning rate greater than 10 cm / s), and Class 3 refrigerants have higher flammability and faster flame propagation (e.g., a burning rate greater than 10 cm / s). Under ASHRAE Standard 34, the commonly used R-410A refrigerant falls into both Class A toxicity and Class 1 flammability categories. Therefore, under ASHRAE Standard 34, R-410A is referred to as A1 refrigerant.

[0006] New low-GWP refrigerants include, but are not limited to, refrigerants such as R-1234yf, R-1234ze, R-32, R-454A, R-454C, R-455A, R-447A, R-452B, and R-454B. Under ASHRAE Standard 34, these refrigerants have a Class A toxicity category and a Class 2L flammability category. These refrigerants may be referred to as "A2L refrigerants." Because A2L refrigerants have the ability to propagate flame, precautions must be taken to prevent accidental leakage and / or accumulation of A2L refrigerant gas, especially in enclosed spaces. However, if the concentration level of an A2L refrigerant is below its lower flammability limit, the A2L refrigerant will not ignite.

[0007] Therefore, it is desirable to provide sensor devices, systems, and methods for rapidly and reliably detecting the presence and / or accumulation of A2L refrigerants and / or other low-GWP refrigerants associated with the operation of devices such as air conditioning and refrigeration systems. Furthermore, to improve reliability and effectiveness, and to ensure that such devices or systems function as designed, it is advantageous to be able to determine whether the normal function or performance of the sensor device or system is degraded, for example, due to barriers between the sensor and its operating environment. Summary of the Invention

[0008] The appended claims set forth novel and useful systems, apparatuses, and methods for sensors. Illustrative embodiments are also provided to enable those skilled in the art to make and use the claimed subject matter.

[0009] This disclosure provides a sensor assembly for detecting and / or monitoring conditions (e.g., the presence and / or accumulation of gases) in a working environment (i.e., a sensing environment). Additionally, the sensor assembly of this disclosure is operable to determine whether the sensor assembly operates efficiently, inefficiently, or not at all, as the sensor assembly's detection element is partially, substantially, or completely blocked relative to the sensing environment.

[0010] The sensor assembly may include a body or housing that defines the internal space of the sensor assembly (i.e., the internal environment or sensor environment). The housing may contain a detection element (e.g., a gas sensor chip), an environmental change catalyst (e.g., a heater), an environmental sensor (e.g., a relative humidity and / or temperature sensor), and a controller. The detection element, environmental change catalyst, and environmental sensor are each electrically connected to the controller.

[0011] The housing includes at least one opening that allows the sensing element to be exposed to the sensing environment. In some configurations of the sensor assembly, the opening includes a barrier (e.g., a semi-permeable membrane) configured to allow gaseous fluid to pass from the sensing environment to the sensor environment and the sensing element, and to restrict unwanted particulate material (e.g., dirt, dust, debris, or other material) from entering the sensor environment.

[0012] The detection element is configured to detect and / or monitor conditions in the sensing environment and provide sensor data or output indicating the conditions in the sensing environment. The detection element communicates with the controller to provide sensor data.

[0013] An environmental change catalyst is configured to induce or force a change in one or more environmental conditions (e.g., temperature, pressure, relative humidity) in the sensor environment. The environmental change catalyst communicates with a controller, and its operation is controlled by the controller.

[0014] Environmental sensors are configured to detect and / or monitor conditions and / or changes in conditions within the sensor environment. The environmental sensors communicate with a controller to provide sensor data or output indicating conditions and / or changes in conditions within the sensor environment.

[0015] The controller is configured or programmed to communicate with the sensing element and to request and / or receive sensor data from the sensing element. The controller is also configured or programmed to communicate with an environmental change catalyst and to control the operation of the environmental change catalyst. Furthermore, the controller is configured or programmed to communicate with an environmental sensor to determine the conditions and / or changes in those conditions within the sensor environment. Additionally, the controller can be configured or programmed to determine, based on the conditions and / or changes in those conditions, whether the openings in the sensor assembly's housing are blocked or restricted, such that the passage of gaseous fluid from the sensing environment to the sensor environment is partially or substantially blocked, or completely blocked or impeded.

[0016] In some configurations, the sensor assembly may employ a data sheet (e.g., a lookup table) that may include empirical information. This empirical information may include the output values ​​of an environmental sensor compiled and validated by operating the sensor assembly under various controlled conditions, including variations in the sensing environment and / or sensor environment (e.g., temperature, pressure, and relative humidity), and variations in the operation of environmental change catalysts (e.g., operating cycle time) and under simulated limiting conditions of openings in the housing (e.g., partial obstruction, substantial obstruction, and complete obstruction). The information in the data sheet can be utilized by a controller or another processor or device connected to the sensor assembly to compare with the real-time output of the environmental sensor to determine the operating condition of the sensor assembly; that is, whether the openings in the housing are obstructed and / or to what extent they may be obstructed.

[0017] In some configurations of the sensor assembly, the sensing element is an A2L refrigerant sensor. In some configurations of the sensor assembly, the environmental change catalyst is a resistance heater. In some configurations of the sensor assembly, the environmental sensor is a relative humidity sensor. In some configurations of the sensor assembly, the controller is configured to selectively energize or de-energize the heater at predetermined time intervals (e.g., provide pulses to the heater) to force changes in environmental conditions (e.g., temperature and / or relative humidity) in the sensor environment.

[0018] In some configurations of the sensor assembly, the controller is configured or programmed to receive output from an environmental sensor, determine any changes in the environmental conditions of the sensor environment, compare the changes in the environmental conditions of the sensor environment with a data table containing values ​​of one or more environmental conditions of the sensor environment that can be expected under specific operating conditions of the sensor assembly, and determine, based on the comparison, whether the opening of the sensor assembly housing is partially blocked, substantially blocked, or completely blocked, and / or whether the sensor assembly is operating normally.

[0019] In some configurations of the sensor assembly, the sensor assembly is a refrigerant sensor, which may include a housing, a refrigerant detection element, a heater, a relative humidity sensor, an optional temperature sensor, and a main processing unit. The main processing unit includes a printed circuit board on which a controller is disposed. The controller is configured to communicate with the refrigerant detection element, the heater, the relative humidity sensor, and the optional temperature sensor, and to receive sensor data (e.g., outputs from the respective sensors). The housing defines an internal space (i.e., the sensor environment) and includes an opening that exposes the refrigerant detection element to the external environment (i.e., the sensing environment). The opening is operable to prevent foreign particulate material from passing from the external environment into the internal space of the sensor assembly and to allow gaseous fluid to pass through to reach the refrigerant detection element located within the internal space. The controller is configured to determine the operating condition of the sensor assembly, including whether the opening is partially blocked, substantially blocked, and / or completely blocked. The heater is disposed within the housing and configured to heat at least a portion of the internal space of the housing under the operation of the controller. The controller is configured to, for example, energize the heater according to a predetermined duty cycle, receive output from a relative humidity sensor, compare the output with a expected output (e.g., a value in a datasheet), and determine whether the sensor assembly is functioning correctly.

[0020] In another aspect of this disclosure, a method of operating a sensor assembly includes acquiring a first reading of an environmental sensor at a first time to measure a first state of at least one second environmental condition in the sensor environment. Then, an environmental change catalyst is operated over a predetermined time period. After the predetermined time period, a second reading of the environmental sensor is acquired at a second time to measure a second state of at least one second environmental condition in the sensor environment. Next, a data table is polled to find data representing a second output of the environmental sensor. The operating condition of the sensor is then determined based on the data from the data table.

[0021] The purpose, advantages, and preferred mode of making and using the claimed subject matter can be best understood by referring to the accompanying drawings in conjunction with the following detailed description of illustrative embodiments. Attached Figure Description

[0022] The accompanying drawings described herein are for illustrative purposes only, and not for all possible implementations, and are not intended to limit the scope of this disclosure.

[0023] Figure 1 This is a functional block diagram of an example implementation of a refrigeration system used in heating, ventilation, and air conditioning systems;

[0024] Figure 2 It is set in Figure 1 A front perspective view of an example sensor assembly in a refrigeration system;

[0025] Figure 3 yes Figure 2 An exploded perspective view of the sensor components;

[0026] Figure 4 It is used for Figure 2 A perspective view of the sensor electronics package of the sensor assembly;

[0027] Figure 5 yes Figure 2 A perspective view of the interior of the sensor assembly cover; and

[0028] Figure 6 yes Figure 2 Functional block diagram of the sensor component.

[0029] Where applicable, corresponding reference numerals indicate the corresponding parts throughout several views of the accompanying drawings. Detailed Implementation

[0030] The following description of exemplary embodiments provides information that enables those skilled in the art to make and use the subject matter set forth in the appended claims, but certain details already known in the art may be omitted. Therefore, the following detailed description should be considered illustrative rather than limiting.

[0031] Figure 1 This is a functional block diagram of an example embodiment of a refrigeration system 100 used in a heating, ventilation, and air conditioning (HVAC) system. Figure 1 As shown, some examples of the refrigeration system 100 may include a refrigeration circuit comprising an evaporator unit 102 and a condenser unit 104. According to some examples, the evaporator unit 102 may be located indoors and referred to as an indoor unit, while the condenser unit 104 may be located outdoors and referred to as an outdoor unit. The evaporator unit 102 may include an evaporator 106, such as an evaporator coil, and the condenser unit 104 may include a compressor 108 and a condenser 110. The evaporator 106, compressor 108, and condenser 110 may be fluidly coupled, for example, via pipes, gas lines, or liquid lines. For example, the evaporator 106 may be fluidly coupled to the compressor 108 via a suction line. In some examples, the evaporator 106 may be fluidly coupled to the condenser 110 via a liquid line. According to an exemplary embodiment, the compressor 108 may be fluidly coupled to the condenser 110 via a hot gas line.

[0032] The refrigeration system 100 allows a working fluid to circulate within the refrigeration circuit. The working fluid can be a low-GWP refrigerant, such as an air-to-liquid (A2L) refrigerant. For example, A2L refrigerants may include R-1234yf, R-1234ze, R-32, R-454A, R-454C, R-455A, R-447A, R-452B, or R-454B. Alternatively, the working fluid can be other liquids, such as water.

[0033] In operation, compressor 108 receives working fluid through its suction port, compresses the working fluid, and discharges the compressed working fluid through its discharge port. After being compressed by compressor 108, the working fluid can be supplied to condenser 110 in gaseous form via a hot gas line. Condenser 110 cools the working fluid, causing it to condense back into liquid form. The working fluid can then be transported from condenser 110 to evaporator 106 via a liquid line. At evaporator 106, heat is absorbed by the working fluid, causing it to expand into a gas or liquid-gas mixture. Due to the phase change of the working fluid from liquid to gas in evaporator 106, the temperature of the working fluid decreases, and the cooled gas can absorb heat energy from evaporator 106, thereby cooling the exterior of evaporator 106 in the process. A fan (not shown) can provide airflow above the exterior of the cooled evaporator 106. As air flows above the exterior of the cooled evaporator 106, evaporator 106 can absorb heat energy from the flowing air, thereby cooling the air. The cooled air can then be supplied to air-conditioned environments, such as the interior of rooms within a building, via a duct system.

[0034] The refrigeration system 100 may also include various monitoring and control devices, such as sensors, thermostats, and processors. For example, evaporator unit sensor 112 may be disposed within the housing member of evaporator unit 102, and condenser unit sensor 114 may be disposed within the housing member of condenser unit 104. Evaporator unit sensor 112 and condenser unit sensor 114 may be operatively coupled to controller 116 (e.g., processor). In some examples, thermostat 118 may be configured to monitor the air-conditioned environment. Thermostat 118 may also be operatively coupled to controller 116. In the illustrative embodiment, an additional environmental sensor 120 may also be disposed and operatively coupled to controller 116.

[0035] Now refer to Figures 2 to 4An exemplary sensor assembly 200 is shown. Sensor assembly 200 may be a sensor of the evaporator unit sensor 112 as previously described, a sensor of the condenser unit sensor 114, or a thermostat 118. Sensor assembly 200 may be a gas sensor, such as an A2L refrigerant sensor or other gas sensors. For example, sensor assembly 200 may be positioned and / or exposed to the operating environment to be sensed (i.e., the sensing environment), such as in or near the evaporator coil, and may detect the presence and / or accumulation of the working fluid in the sensing environment (i.e., outside the refrigeration circuit) (e.g., in a gaseous state), particularly A2L refrigerant, which indicates a leak in the refrigeration circuit and / or other malfunctions in the refrigeration system.

[0036] Sensor assembly 200 may provide a housing 204 that encloses sensor electronics package 228 within the internal space of the sensor assembly (i.e., the sensor environment). Sensor electronics package 228 may include detection elements (e.g., gas sensor 284), environmental change catalysts (e.g., one or more heaters 304), environmental sensors (e.g., relative humidity sensor 286 and / or temperature sensor 308), and a programmable or programmable controller 260, all of which are disposed on a printed circuit board (PCB) 250.

[0037] The housing 204 may include an opening 227 that allows the sensor environment to communicate freely with the sensing environment. The opening also exposes the sensing element 284 to the sensing environment and enables the sensing element 284 to sense one or more undesirable conditions in the sensing environment, such as the presence or accumulation of working fluid.

[0038] An environmental change catalyst (e.g., including heater 304) may also be operated by controller 260 to obtain and / or maintain a temperature in the sensor environment above the dew point of the sensing environment, and the environmental sensor may provide output or data that enables controller 260 or another processor associated with sensor assembly 200 to compensate for the output from sensor assembly 200 in response to environmental conditions (e.g., temperature, humidity, and / or pressure) in the sensing environment.

[0039] Furthermore, in the sensor assembly 200 of this disclosure, the controller 260 may employ an environmental change catalyst 304 to force a known change in the environmental conditions (e.g., temperature and / or relative humidity) of the sensor environment by controlling the operation of the environmental change catalyst 260 according to a predetermined or programmed duty cycle (e.g., causing the heater to pulse on / off) while simultaneously monitoring the output of the environmental sensors (e.g., temperature and / or relative humidity). Therefore, the sensor assembly 200 of this disclosure can assess changes in the environmental conditions (e.g., relative humidity) of the sensor environment over time.

[0040] If the sensor assembly 200 and / or the sensing element 284 is confined to or becomes confined to the sensing environment (e.g., partially blocked, substantially blocked, or completely blocked), such as when foreign matter (e.g., particles such as dirt, dust, and lint, and liquids such as oil, condensate, etc.) accumulates in the opening 227 in the housing 204, the sensor environment cannot freely communicate with the sensing environment. The applicant has recognized that one consequence of such confinement is that water vapor present in the confined space (or volume) of the sensor environment (e.g., as measured by relative humidity) cannot easily exchange with or disperse into the relatively large space (or volume) of the sensing environment through the opening 227, and therefore, if the sensor environment were to freely communicate with the sensing environment, the relative humidity in the sensor environment would not change in response to changes in the temperature of the sensor environment as expected or desired.

[0041] Therefore, the applicant has determined that by employing an environmental sensor (e.g., relative humidity sensor 286 and / or temperature sensor 308) to monitor one or more environmental conditions (e.g., relative humidity and / or temperature) in the sensor environment while employing an environmental change catalyst (e.g., a heater) to force a corresponding known or predicted change in the sensor environment (e.g., by increasing the temperature by turning on the heater), and then comparing the subsequent output from the environmental sensor (e.g., representing a change in relative humidity) with the expected output from the environmental sensor (e.g., representing or reflecting an expected or predicted change in relative humidity due to an increase in temperature), the sensor assembly 200 of this disclosure can be configured to determine whether the sensor assembly 200 operates efficiently, inefficiently, or not at all due to the opening 227 in the housing 204 being open, partially blocked, substantially blocked, or completely blocked.

[0042] The expected or predicted output of the environmental sensor (e.g., representing or reflecting changes in the relative humidity of the sensor environment) may include information (e.g., empirical data) from a data table (e.g., a lookup table) that has been compiled and verified by operating the sensor assembly under various but controlled conditions (including changes in the surrounding environment (e.g., temperature, pressure, and relative humidity), periodic operation of the heater (i.e., power-on and power-off intervals)) and simulated limiting conditions of the opening 227 in housing 204 (e.g., partial, substantial, or complete obstruction of opening 227), and by recording or storing the outputs of the environmental sensors (e.g., relative humidity sensor 286 and / or temperature sensor 308). The data table may be utilized (e.g., searched or polled) by controller 260 or another processor or device connected to sensor assembly 200 to compare with subsequent outputs from the environmental sensors and determine the operating condition of sensor assembly 200 based on the comparison result.

[0043] The housing 204 of the sensor assembly 200 may define the internal space of the sensor assembly (i.e., the sensor environment). The housing 204 may include one or more external tabs 216. The tabs 216 may project laterally outward and include holes 220 for mounting or assembling the housing 204 to a support structure in the working environment (e.g., the cooling system 100).

[0044] The housing 204 may have a multi-piece clamshell structure including a cover 226 and a base 230. The base 230 may be integrally and monolithically formed with the tab 216. The base 230 may define a recess or cavity 231 for receiving an electronic device package 228.

[0045] The cover 226 can close and seal the recess or cavity 231 in the base 230 to isolate the internal space of the sensor assembly (i.e., the sensor environment) from the external operating environment (i.e., the sensing environment). The cover 226 may include a skirt 229 configured to fit onto a stepped portion or rib 233 of the base 230, such that the cover 226 can seal against the base 230. The cover 226 can also seal against the base 230 at surface 235. If desired, a sealing element such as a gasket or O-ring may be provided between the cover 226 and the base 230 to further enhance the seal.

[0046] The base 230 and the cover 226 may each be formed of plastic, metal, or any other suitable material or combination of materials. The base 230 and the cover 226 may each be formed by injection molding or other suitable means.

[0047] The structure of housing 204 allows sensor assembly 200, such as evaporator 102 of cooling system 100, to be located in harsh environments. Housing 204 may be solid and used to protect sensor electronics package 228. Housing 204 may also have ports 222 in the side of cover 226 to provide access to connector 252 of electronics package 228.

[0048] like Figure 5As best seen, housing 204 may optionally include one or more barriers 246. Barriers 246 may divide the internal space of sensor assembly 200 into a first cavity 236 containing a detection element (e.g., gas sensor 284) and an environmental sensor (e.g., RH sensor 286 and / or temperature sensor 308) and a second cavity 240 containing the remainder of electronics package 228 (including an environmental change catalyst (e.g., heater 304)). Alternatively, the environmental change catalyst (e.g., heater 304) may be contained in the first cavity 236 and positioned near the detection element. Barrier 246 may be a protrusion integral with and extending from the underside of cover 226 of housing 204. Depending on the sensor location, barrier 246 may provide a seal between the first cavity 236 and the second cavity 240.

[0049] The housing 204, particularly the cover 226 of the housing 204, may include an opening 227 leading into the first cavity 236, allowing at least the sensing element to be exposed to the sensing environment. One or more membranes and / or filters 440 may be located above and cover the opening 227. The membranes and / or filters 440 may be semi-permeable barriers, allowing gases and / or vapors to pass from the sensing environment through the opening 227 and into the cavity 236 to reach the sensing element, while also minimizing or preventing impurities (including particles such as dirt, dust, and lint, and liquids such as oil, condensate, etc.) that may be present in the sensing environment from entering the first cavity 236 and negatively impacting the operation of the sensing element. The membranes and / or filters 440 may be formed of elastomers, fabrics, or other suitable materials.

[0050] In addition to detection elements (e.g., gas sensor 284), environmental change catalysts (e.g., one or more heaters 304), environmental sensors (e.g., relative humidity sensor 286 and / or temperature sensor 308), and controller 260, sensor electronics package 228 may also include other known and understood electronic components mounted on printed circuit board 250, such as power supplies, switches, filters / signal conditioners, A / D converters, LEDs, and connectors 252. Printed circuit board 250 may be sized to fit within cavity 231 and may be contained within the internal space of housing 204. First printed circuit board 250 may include one or more holes 276 into which corresponding posts 277 of cover 226 and / or base 230 may engage for mounting within housing 204.

[0051] Connector 252 can be a Universal Serial Bus (USB) to Serial (such as transistor-to-transistor logic, TTL interface) converter (e.g., Future Technology Equipment International). TM FTDITM A connector 252 is configured to receive a cable and transmit sensor output or data from sensor assembly 200. Connector 252 may be located at an end of the first printed circuit board 250 such that connector 252 is aligned with an opening 222 in the cover 226 of housing 204.

[0052] The controller 260 can communicate with the sensing element, environmental change catalyst, environmental sensor, and other components of the sensor electronics package 228 to control various functions and operations of the sensor assembly 200. The controller 260 can transmit sensor output or data from the sensor assembly 200 via connector 252. A wiring harness connected to connector 252 can transmit the sensor output from connector 252 to various external controllers or devices.

[0053] In addition to its function in determining whether sensor assembly 200 is functioning effectively, heater 304 can also be used to reduce condensation of moisture within the internal space of sensor assembly 200, particularly within cavity 236. Typical condensation of relative humidity (RH) can occur at cooler temperatures, such as ambient air temperatures below 25°C. During the summer, water can accumulate in the evaporator coils because the coil temperature is below the dew point temperature of the inlet air. When a sensor (such as sensor assembly 200) is attached to the evaporator coil assembly, water can accumulate in cavities 236, 240 for at least the same reasons. Heater 304 reduces condensation of moisture by internally heating the sensor electronics to prevent the sensor temperature from dropping below the dew point temperature.

[0054] Now refer to Figure 6 The diagram shows a functional block diagram of sensor assembly 200. Sensor assembly 200 includes housing 204, which encloses controller 260, RH sensor 286, gas sensor 284, temperature sensor 308, power supply 312, relay or switch 316, and heater 304.

[0055] The controller 260 can communicate with the switch 316 and can be configured to actuate the switch 316 to connect the power supply 312 to the heater 304. The controller 260 can actuate and de-actuate the switch 316 to input electrical pulses from the power supply 312 to the heater 304 according to a predetermined or preferred duty cycle.

[0056] The controller 260 can be configured to request and receive sensor data from the RH sensor 286, the temperature sensor 308, and / or the gas sensor 284. More specifically, the sensor data may include outputs or readings from one or both of the RH sensor 286 and the temperature sensor 308. The sensor data may also include outputs from the gas sensor 284 (e.g., an A2L sensor chip).

[0057] The controller 260 can process sensor data to transmit sensor output via connector 252. Additionally, the controller 260 (or an external device communicating with the controller) can use the sensor data to determine whether the sensor assembly 200 is functioning effectively, including whether the communication between the sensing element and the sensing environment is partially or completely blocked.

[0058] When the change in relative humidity 286 of the sensor environment caused by the controlled operation of heater 304 is inconsistent with the expected or predicted change in relative humidity of the sensor environment caused by the temperature change of the sensor environment, the limiting or blocking condition can be determined by controller 260 (or another external controller or device connected to sensor assembly 200 via connector 252).

[0059] Therefore, determining whether the sensor assembly 200 is operating efficiently, inefficiently, or not at all due to the opening 227 in the housing 204 being open, partially blocked, substantially blocked, or completely blocked can include the following.

[0060] First, an environmental sensor reading is acquired at a first time to measure the first state of at least one second environmental condition in the sensor environment. Then, the environmental change catalyst is run for a predetermined period of time. Subsequently, at a second time after the predetermined period, a second environmental sensor reading is acquired to measure the second state of at least one second environmental condition in the sensor environment. A data table is then polled to obtain data representing or reflecting a second output of the environmental sensor or related to that second output. Afterward, the sensor's operating condition can be determined using the data table.

[0061] The first reading from the environmental sensor can be the relative humidity in the sensor environment. The catalyst for this environmental change can be a heater, which is periodically operated to force a known change in the sensor environment (e.g., periodically turning on the heater over a predetermined time period to influence an increase in the ambient temperature of the sensor environment, thereby correspondingly affecting the relative humidity). A second reading from the environmental sensor (e.g., at the end of the predetermined time period) can again measure the relative humidity. The controller can then poll (or search) a data table to obtain data that represents or reflects the readings of the environmental sensor or is related to those readings.

[0062] The output of the environmental sensor (e.g., changes in relative humidity) can be correlated with empirical information stored in a data table. The empirical information can be compiled and verified by operating the sensor assembly under various but controlled conditions (including changes in the surrounding environment (e.g., temperature, pressure, and relative humidity), periodic operation of the heater (i.e., power-on and power-off intervals)) and under simulated limiting conditions for the opening 227 in housing 204, and recording the output of the environmental sensor.

[0063] Then, the controller 260 or another processor or device connected to the sensor assembly 200 can use a data table to compare with the real-time output from the environmental sensor to determine the operating status of the sensor assembly 200; that is, whether the opening 227 in the housing 204 is blocked. In this regard, for example, the data table can be polled (e.g., searched) based on the real-time output from the environmental sensor to determine the corresponding status of the opening in the housing in relation to the environmental sensor output.

[0064] Alternatively or additionally, controller 260 may actuate heater 304 to mitigate condensation in sensor assembly 200, as described by the applicant in U.S. Patent No. 12,241,810 entitled “Sensor Assembly,” the entire contents of which are incorporated herein by reference. Furthermore, the methods described herein for identifying obstructions in sensor assemblies can be applied to other sensor structures, including those described by the applicant in the aforementioned U.S. Patent No. 12,241,810 and in the applicant's U.S. Patent No. 12,275,575 entitled “Sensor Assembly and Refrigerant Sensing System,” the entire contents of which are incorporated herein by reference.

[0065] Although illustrated in these illustrative embodiments, those skilled in the art will recognize that the systems, apparatus, and methods described herein are readily adaptable to various variations and modifications falling within the scope of the appended claims. Furthermore, descriptions of various alternatives using terms such as “or” need not be mutually exclusive unless the context explicitly requires it, and the indefinite articles “a” or “an” do not limit the subject matter to a single instance unless the context explicitly requires it. The components may also be combined or eliminated in various configurations for purposes of sale, manufacture, assembly, or use.

[0066] The appended claims set forth the novelty and inventive step aspects of the subject matter described above; however, the claims may also cover additional subject matter not specifically detailed. For example, if it is not necessary to distinguish novel and inventive features from features known to those skilled in the art, certain features, elements, or aspects may be omitted from the claims. Features, elements, and aspects described in the context of some embodiments may also be omitted, combined, or replaced by alternative features having the same, equivalent, or similar purpose without departing from the scope of the invention as defined by the appended claims.

Claims

1. A sensor for detecting conditions in a sensing environment, comprising: A housing that defines the internal space of the sensor, including the sensor environment; A detection element configured to detect at least one first environmental condition in the sensing environment and provide a first output indicating the at least one first environmental condition in the sensing environment; Catalysts for environmental change; An environmental sensor configured to detect at least one second environmental condition in the sensor environment and provide a second output indicating the at least one second environmental condition in the sensor environment; A controller configured to communicate with the detection element, the environmental change catalyst, and the environmental sensor; and The detection element, the environmental change catalyst, and the environmental sensor are located inside the housing; The housing includes an opening that exposes the detection element to the sensing environment, the opening including a barrier configured to allow gaseous fluid to pass from the sensing environment to the detection element; A data table, comprising data obtained by operating the sensor under various controlled conditions; The controller is configured to determine the operating status of the sensor.

2. The sensor according to claim 1, wherein, The controller is configured to poll the data table based on the second output of the environmental sensor to determine the operating status of the sensor.

3. The sensor according to claim 2, wherein, The data in the data table includes empirical data related to the second output of the environmental sensor.

4. The sensor according to claim 3, wherein, The data in the data table includes empirical data related to the second output of the environmental sensor obtained by operating the sensor under various controlled environmental conditions in the sensor environment and under simulated restrictive conditions of the opening in the housing.

5. The sensor according to claim 4, wherein, The controller is configured to determine whether the opening is restricted such that the passage of gaseous fluid from the sensing environment through the opening is at least one of the following: partially prohibited, substantially prohibited, or completely prohibited.

6. The sensor according to claim 1, wherein, The controller is configured to compare the second output of the environmental sensor with the data in the data table to determine whether the opening in the housing is blocked.

7. The sensor according to claim 6, wherein, The data in the data table includes empirical data representing the second output of the environmental sensor obtained by operating the sensor under various controlled environmental conditions in the sensor environment and under simulated restrictive conditions of the opening in the housing.

8. The sensor according to claim 1, wherein, The controller is configured to control the operation of the environmental change catalyst to cause a change in the at least one second environmental condition in the sensor environment; The environmental sensor is configured to provide the second output at a first time and a second time; and The controller is configured to receive the second output of the environmental sensor at the first time and the second output of the environmental sensor at the second time.

9. The sensor according to claim 8, wherein, The controller is configured to compare at least one of the second output of the environmental sensor provided at the first time and the second output of the environmental sensor provided at the second time with the data in the data table to determine whether the opening in the housing is blocked.

10. The sensor according to claim 9, wherein, The data in the data table includes empirical data reflecting the second output of the environmental sensor obtained by operating the sensor under various controlled environmental conditions in the sensor environment and under simulated restrictive conditions of the opening in the housing.

11. The sensor according to claim 10, wherein, The controller is configured to determine whether the opening in the housing is restricted such that the passage of gaseous fluid from the sensing environment through the opening is at least one of the following: partially prohibited, substantially prohibited, or completely prohibited.

12. The sensor according to claim 11, wherein, The detection element is an A2L refrigerant sensor; The environmental change catalyst is a resistance heater; Wherein, the environmental sensor is a humidity sensor; and The controller is configured to cyclically supply power to the resistive heater to cause a change in at least one second environmental condition of the sensor environment.

13. The sensor according to claim 12, wherein, The opening includes a semi-permeable barrier.

14. The sensor according to claim 8, wherein, The controller is configured to: determine a change in at least one second environmental condition in the sensor environment, compare the change in the at least one second environmental condition in the sensor environment with data in the data table, and determine the operating status of the sensor, the operating status including at least one of whether the opening of the sensor housing is restricted and whether the sensor is operating normally.

15. The sensor according to claim 14, wherein, The controller is configured to determine whether the opening of the housing is restricted, such that the passage of gaseous fluid from the sensing environment through the opening is at least one of the following: partially prohibited, substantially prohibited, or completely prohibited.

16. A method for operating a sensor according to claim 1, comprising: Acquire a first reading from the environmental sensor to measure a first state of the at least one second environmental condition in the sensor environment; Operate the environmental change catalyst; Acquire a second reading from the environmental sensor to measure a second state of the at least one second environmental condition in the sensor environment; Poll the data table to find the data representing the second output of the environmental sensor; as well as The operating status of the sensor is determined based on the data from the data table.

17. The method according to claim 16, wherein, Determining the operating status of the sensor includes determining at least one of the following: whether the opening of the sensor housing is restricted, and whether the sensor is operating normally.

18. The method according to claim 16, wherein, Determining the operating status of the sensor includes determining whether the opening of the housing is restricted such that the passage of the gaseous fluid from the sensing environment through the opening is at least one of the following: partially prohibited, substantially prohibited, or completely prohibited.

19. The method of claim 16, further comprising comparing the first state with the second state, and determining a state change of the at least one second environmental condition of the sensor environment; and in, Polling the data table includes finding data representing the state changes of the at least one second environmental condition of the sensor environment.

20. A method for operating a sensor according to claim 12, comprising: Acquire the first reading of the environmental sensor at the first moment to measure the first state of the at least one second environmental condition in the sensor environment; The environmental change catalyst is cyclically powered; A second reading from the environmental sensor is acquired at a second time to measure a second state of the at least one second environmental condition in the sensor environment; Poll the data table to find the data representing the second output of the environmental sensor; as well as The operating status of the sensor is determined based on the data from the data table.

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