SYSTEM FOR DETERMINING FORCE IMPARTED BY A FILTER IN A VARIABLE FLOW ENVIRONMENT AND RELATED METHODS OF USE
20200188831 ยท 2020-06-18
Assignee
Inventors
Cpc classification
F24F11/39
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Y02A50/20
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
G01L1/26
PHYSICS
F24F11/30
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F24F8/108
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G01N15/082
PHYSICS
International classification
B01D46/00
PERFORMING OPERATIONS; TRANSPORTING
F24F11/30
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F24F3/16
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G01L1/26
PHYSICS
Abstract
A control system for a variable flow filtration system that is configured for receiving an operating condition of a variable speed impeller of the variable flow filtration system; determining a threshold filter force associated with the received operating condition to determine an increased threshold filter force proportionally to increases in the received operating condition; receiving one or more real-time environmental conditions of the variable flow filtration system; modifying the determined threshold filter force based on the received one or more real-time environmental conditions; receiving a real-time filter force imparted by a filter of the variable flow filtration system on a load cell or other filtration system component, the filter force being imparted by a flow of gas or fluid driven by the variable speed impeller; comparing the received real-time filter force to the modified determined threshold filter force; and generating a filter status notification based on the comparison.
Claims
1-20. (canceled)
21. A computer-implemented method, comprising: determining a threshold based on one or more first conditions of a variable speed first component of a filtration system and one or more second conditions; receiving, from a sensor, a force imparted by a filter of the filtration system on the sensor and/or a second component of the filtration system, the force of the filter on the sensor and/or the second component being imparted by a flow of air, gas, or fluid driven by the variable speed first component; comparing the received force to the determined threshold ; and generating a notification or signal based on the comparison of the force to the determined threshold.
22. The computer-implemented method of claim 21, wherein the one or more first conditions include one or more of a fan setting, a pump setting, an intensity setting, a fan speed, a rotational velocity, a voltage, a current, an air/fluid flow rate, or a force.
23. The computer-implemented method of claim 21, wherein the one or more second conditions include one or more of a temperature measurement, a humidity measurement, an air or fluid density measurement, an altitude measurement, or an air or fluid pressure measurement of the filtration system.
24. The computer-implemented method of claim 21, wherein at least one of the one or more first conditions, the one or more second conditions, or the force, is received continuously in real-time.
25. The computer-implemented method of claim 21, wherein determining a threshold includes modifying an initially determined threshold based on changes in the one or more second conditions.
26. A control system for a variable flow filtration system, the control system comprising: a digital data storage device storing instructions for generating a notification or signal; and a processor configured to execute the stored instructions to perform a method comprising: determining a threshold based on a first condition of a variable speed first component of the variable flow filtration system and one or more second conditions; receiving, from a sensor, a force imparted by a filter of the variable flow filtration system on the sensor or on a second component of the variable flow filtration system, the force of the filter being imparted by a flow of air, gas, or fluid moved by the variable speed the first component; comparing the received force to the determined threshold ; and generating the notification or signal based on the comparison of the force to the determined threshold.
27. The control system of claim 26, wherein the first condition includes one or more of a fan setting, a pump setting, an intensity setting, a fan speed, a rotational velocity, a voltage, a current, an air/fluid flow rate, or a force associated with the variable speed first component of the variable flow filtration system.
28. The control system of claim 26, wherein the one or more second conditions includes one or more of a temperature measurement, a humidity measurement, an air or fluid density measurement, an altitude measurement, or an air or fluid pressure measurement of the variable flow filtration system.
29. The control system of claim 26, wherein the sensor is mounted at surface of the filter facing upstream, facing downstream, and/or facing perpendicular to the flow of gas or fluid.
30. The control system of claim 26, wherein the sensor is configured to measure a compressive or tensile force exerted by the filter.
31. The control system of claim 26, wherein determining a threshold includes modifying an initially determined threshold based on changes in the one or more second conditions.
32. A variable flow filtration system, comprising: a filter disposed across a flow of fluid or gas; a variable speed first component configured to move air, fluid, or gas through the filter; a sensor disposed adjacent to the filter and/or a second component of the variable flow filtration system; and a controller configured to: determine a threshold associated with one or more first conditions of the variable speed first component and one or more second conditions; receive, from the sensor, a force imparted by the filter of the variable flow filtration system on the sensor or the second component of the variable flow filtration system; compare the received force to the determined threshold ; and generate a notification or signal based on the comparison of the force to the determined threshold.
33. The variable flow filtration system of claim 32, wherein the one or more first conditions includes one or more of a fan setting, a pump setting, an intensity setting, a fan speed, a rotational velocity, a voltage, a current, an air/fluid flow rate, or a force associated with the variable speed first component of the variable flow filtration system.
34. The variable flow filtration system of claim 32, wherein the one or more second conditions includes one or more of a temperature measurement, a humidity measurement, an air or fluid density measurement, an altitude measurement, or an air or fluid pressure measurement of the variable flow filtration system.
35. The variable flow filtration system of claim 32, wherein determining the threshold includes modifying an initially determined threshold based on changes in the one or more second conditions.
36. The variable flow filtration system of claim 32, wherein the filter is located upstream or downstream of the variable speed first component.
37. The variable flow filtration system of claim 32, wherein the controller is further configured to: receive the one or more first conditions at a first interval; receive the one or more second conditions at a second interval; and receive the force from the sensor at a third interval, wherein the first, second, and third intervals are different from each other or the same.
38. The variable flow filtration system of claim 32, wherein the sensor is configured to measure a compressive or tensile force exerted by the filter.
39. The variable flow filtration system of claim 32, wherein the variable speed first component moves fluid or gas through the filter in a non-uniform path.
40. The variable flow filtration system of claim 32, wherein the sensor is mounted at surface of the filter facing upstream, facing downstream, and/or perpendicular to the movement of air, gas, or fluid.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and together with the description, serve to explain the principles of the disclosed embodiments.
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DESCRIPTION OF THE EMBODIMENTS
[0032] Reference will now be made in detail to the exemplary embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
[0033] In general, the present disclosure is directed to systems and methods for determining when a filter of an air or gas/fluid filtration system is dirty and should be changed or cleaned. The present disclosure is applicable to any type of filtration system, including but not limited to HVAC systems, fluid filtering systems, water filtration, oil filtration, or any other application in which a filter is used to capture particulate matter from a flow of air and/or fluid. By way of example,
[0034] At a high level, the present disclosure describes a system comprising a load sensor positioned in relation to any type of filter, the load sensor being configured to detect and measure an amount or extent of loading or force of the filter on the load sensor and/or on a member or frame proximate to the filter. The load sensor may be any type of transducer configured to create an electrical signal in proportion to a force being measured. By way of example, the load sensor may be a hydraulic load cell or one utilizing hydraulic forces, a pneumatic load cell or one utilizing compressive gaseous forces, a piezoelectric load cell, and/or a strain gauge load cell, pressure sensitive thin film embodiments (such as those used in touch screen applications), laser displacement force measurement devices, and/or linear and non-linear displacement force measurement devices
[0035] In one embodiment, the load cell may be configured to transmit the amount or extent of loading or force for purposes of a comparison against a variable baseline level of force of the filter, by which the load cell may detect loading and/or force even in cases where the filter media may not necessarily deform at all, or even in cases where the filter media deforms by a relatively small or undetectable amount. For example, whereas in traditional filtration applications a filter may be under a relatively binary distribution of forces (i.e., the blower or pump is either on or off), the filter of the present disclosure may be positioned within a variable speed air or fluid/gas environment. For example, the filtration system consistent with the present disclosure may include a fan, blower, pump, or any other impeller configured to move air, fluid, and/or gas at selectively variable speeds. In one embodiment, the fan, blower, pump, etc. of the present disclosure may be positioned in communication with a variable speed drive. For example, the fan, blower, pump, etc. may be disposed in communication with, and indeed driven by, any desired type of variable-frequency drive (VFD), adjustable-frequency drive (AFD), variable-speed drive (VSD), AD drive, micro drive, inverter drive, or any other type of electro-mechanical drive means that controls a motor speed by varying input frequency, current, and/or voltage.
[0036] In one embodiment, the variable speed drive and the load sensor may be provided in communication with a controller that is configured to perform a method of determining an amount or extent of filter loading or clogging. For example, in one embodiment, the controller may be configured to receive a value of operation of a fan or blower of a variable speed filtration (e.g., HVAC or fluid) system. The value of operation of the fan or blower may include one or more of a fan setting, a pump setting, an intensity setting, a fan speed, a rotational velocity, a voltage, a current, an air/fluid flow rate, or a force associated with the fan or blower. Moreover, the value of operation of the fan or blower may include and/or be supplemented by a temperature measurement, a humidity measurement, an air or fluid density measurement, an altitude measurement, an air or fluid pressure measurement. Moreover, the value of operation of the fan or blower may include and/or be supplemented by measurements or parameters associated with changes in height, location, and/or temperature of one or more components of the filtration system. The controller may further be configured to receive, from the load sensor, a value of force of a filter of the filtration system against the load sensor or another member of the filtration system. The controller may further be configured to compare the received value of force of the filter to either the received value of operation of the fan or blower, or a predetermined value of force stored in relation to the value of operation of the fan or blower. Finally, the controller may be configured to determine whether to generate a signal associated with the filter being more loaded, clogged, or dirty, than desired. In one embodiment, the controller may generate a signal associated with the filter being more loaded, clogged, or dirty, than desired, if the received value of force of the filter is outside a threshold value (i.e., below a lower threshold or above an upper threshold) from the received value of operation of the fan or blower, or the predetermined value of force stored in relation to the value of operation of the fan or blower.
[0037] It should be appreciated that the arrangement of the load sensor and the filter in communication with the controller may enable detection of increased force even in cases when the filter is not deformed, which may be especially advantageous in scenarios in which filter deformation is especially undesirable. In other words, the presently disclosed systems and methods may involve triggering a signal indicative of filter clogging at a threshold prior to deformation occurring. As described above, the threshold may be dependent on the type of filter media being used. For example, high efficiency filters (often referred to as HEPA filters), which are used to remove the smallest of particulate sizes, exert a greater force in the direction of flow, whereas other filter media designed to capture the larger particulate matter may have a much greater free area ratio. Thus, the presently disclosed arrangement may enable setting a threshold depending on the type of filter media, whether dense to capture small particulate, or very porous, for use in direct correlation to the speed of the flow. For example, if an HVAC system with a HEPA filter involves high volume flow at one point in time, then the force exerted by the filter may be much greater in comparison to a point in time where the required flow rate is much lower. With a known relationship between the free area of the filter, and its inherent ability to restrict flow, and the speed of the air mover, for example, the system may determine a threshold for triggering an indication of filter clogging. With the type of media entered into the controller, in addition to or in alternative to its free area ratio, the controller which receives the output of the force applied by the filter media may determine the appropriate threshold for triggering an alarm, thereby preventing artificial false triggers. For example, if a threshold is set with the flow at capacity, then a false trigger may occur at high flow due to the inherent higher forces exerted at higher speeds. Additionally, any changes in humidity or density would also impact the forces exerted on the filter. The controller therefore may be configured to gather several environmental conditions to more accurately determine the appropriate threshold.
[0038] In one embodiment, for example, if a VFD-driven fan is operating at, for example, 1025 RPM, to drive 78 degree Fahrenheit air into an environment at 72 degrees Fahrenheit, then the tolerable range of filter forces should be 145-155 PSI. If the force of the filter is outside the 145-155 PSI range while the fan is operating within 5-10% of 1025 RPM, then an alarm may be triggered. In some embodiment, a matrix, curve, mapping/map, or look-up table of tolerable forces may be generated and accessed all possible operating conditions and/or environmental conditions of the VFD-driven fan.
[0039] It should be appreciated that the presently disclosed systems and methods are advantageously improved over existing systems that are applicable only to particular filtration systems. For example, the presently disclosed systems are applicable not only to air filtration, but also to any flowing gas or liquid. Moreover, the presently disclosed load sensors may be positioned not only downstream from a filter, but alternatively or additionally upstream from a filter, and/or perpendicularly to a fluid/gas flow. Moreover, the presently disclosed load sensors may be used in relation not only to deformable filter media, but also to rigid filter media, and to any shape of filter media. Moreover, the presently disclosed load sensors do not just trigger a dirty filter alarm at a single predetermined load (e.g., akin to on/off switch), but rather they enable a continuum or gradient of loads in varying atmospheric conditions, any of which may trigger different types of alarms or actions, and which may be normalized to account for a particular level and/or direction of air/fluid flow.
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[0041] Nevertheless, as shown in
[0042] As shown in
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[0044] In one embodiment, the fluid filtration system of
[0045] The systems of
[0046] Referring now to
[0047] Load sensor 108 may communicate a signal to a receiver or other suitable device to indicate a loading condition of filter media 104. For example, as described herein, the receiver configured to receive a signal of load sensor 108 may be a component of VFD 40, controller 44, thermostat 46, and/or user interface device 48. In some embodiments, load sensor 108 may continuously send a signal to the receiver. In an alternative embodiment, load sensor 108 may send a signal only if a measured force exceeds a threshold force (e.g., indicating that the filter media 104 should be changed). In some embodiments, load sensor 108 may send a signal only in response to a request made by the receiver. It should be appreciated that the load sensor 108 (e.g., a load cell) can be connected through either a wired or wireless interface to transfer its signal to electronics and thereby trigger an alarm or some indication that it is time to change the filter. A user, such as a contractor and/or homeowner, could configure the trigger point based on the type of filter media, flow rate, an elapsed time of the increased force (to prevent false triggers due to start up) and flow density, to name a few.
[0048] Again, it should be appreciated that in the case of the load sensor 108 of system 100 (depicted in
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[0055] Any of the systems described above with respect to
[0056] In one embodiment of method 900, the received operating condition may be received continuously in real-time, the one or more real-time environmental conditions may be received continuously in real-time, and the real-time filter force may be received from the load cell continuously in real-time. Alternatively, the received operating condition may be received at a first predetermined interval, the one or more real-time environmental conditions may be received at a second predetermined interval, and the real-time filter force may be received from the load cell at a third predetermined interval, wherein the first, second, and third predetermined intervals are different from each other or the same. In yet another exemplary embodiment, the real-time filter force may be received from the load cell continuously in real-time, whereas the one or more received operating conditions may be received at a first predetermined interval (e.g., every second, every 30 seconds, every minute, every 15 minutes, etc.), and the one or more real-time environmental conditions may be received at a second predetermined interval different from the first predetermined interval (e.g., a different one of every second, every 30 seconds, every minute, every 15 minutes, etc.).
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[0058] Method 1000 may further include receiving one or more real-time environmental conditions of the filtration system (step 1006). For example, method 1000 may include receiving one or more of a temperature measurement, a humidity measurement, an air or fluid density measurement, an altitude measurement, or an air or fluid pressure measurement of the filtration system. Method 1000 may further include modifying the determined threshold filter force based on the received one or more real-time environmental conditions (step 1008). For example, the determined threshold filter force may be modified so as (i) to decrease the determined threshold filter force proportionally to increases in the temperature measurement and/or proportionally to increases in the altitude measurement; and (ii) to increase the determined threshold filter force proportionally to increases in the humidity measurement, to increases in the air or fluid density measurement, and/or to increases in the air or fluid pressure measurement of the filtration system.
[0059] Method 1000 may further include receiving, from a load cell, a real-time filter force imparted by a filter of the filtration system on the load cell and/or a component of the filtration system, the force of the filter on the component being imparted by a flow of gas or fluid driven by the variable speed impeller (step 1010), comparing the received real-time filter force to the modified determined threshold filter force (step 1012), and generating a filter status notification or signal based on the comparison of the real-time filter force to the determined threshold filter force (step 1014).
[0060] Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.