CN116447739A

CN116447739A - Air brake

Info

Publication number: CN116447739A
Application number: CN202310483974.9A
Authority: CN
Inventors: 肖恩·H·思科尔腾; 奥瑞慕思·阿纽利斯; 达蒙·布莱恩·史密斯
Original assignee: Johnson Controls Tyco IP Holdings LLP
Current assignee: Johnson Controls Tyco IP Holdings LLP
Priority date: 2018-01-17
Filing date: 2019-01-17
Publication date: 2023-07-18
Also published as: CN112136008A; MX2020007615A; CA3088804A1; WO2019143863A1; CN112136008B; EP3740722A1

Abstract

An air brake assembly for an air duct having an inner wall and an outer wall is provided. The air brake assembly includes an air brake plate having a perimeter and a plurality of teeth spaced at least partially around and extending from the perimeter. The plurality of teeth vary in length around the perimeter from a maximum value to a minimum value over a span of about 90 degrees. The air brake assembly further includes a bridge shaft assembly fixedly coupled to the air brake plate and rotatably coupled to the air duct. Rotation of the axle assembly rotates the damper plate within the air duct between a fully open position and a fully closed position to increase or decrease the flow of fluid through the air duct.

Description

Air brake

The present application is a divisional application of the invention patent application with the application date of 2019, 1 month and 17 days, the international application number of PCT/US2019/014085, the national application number of 201980018253.2 and the invention name of "air brake".

Cross Reference to Related Applications

The present application claims the benefit and priority of U.S. provisional patent application number 62/618,206 filed on day 1, month 17 of 2018 and U.S. provisional patent application number 62/618,142 filed on day 1, month 17 of 2018. Both of these patent applications are incorporated herein by reference in their entirety.

Background

In an exemplary embodiment, the present disclosure relates to an air duct brake and an air duct airflow sensor. More particularly, exemplary embodiments relate to air brakes having controllable resolution at lower flow rates.

An air lock is a mechanical valve for allowing, blocking, and controlling the flow of air in an air duct. Conventional dampers typically include circular blades having a shaft passing through the diameter of the blade, the end of the shaft rotatably mounted in the air duct wall. The diameter of the vanes is slightly smaller than the diameter of the circular (or other cross-sectional shape) air duct so that when the vanes are in the closed position, all or substantially all of the airflow is blocked without air passing between the edges of the vanes and the inner wall of the air duct. A motor or other control mechanism is associated with the axle shaft and when actuated rotates the shaft, which rotates the vanes between an open position, a closed position, or a partially open position to allow controlled flow of air through the duct. One or more sensors are disposed adjacent the damper for measuring air flow. The sensor is connected to a processor that actuates a motor that controls the rotation of the blades, thereby controlling the desired airflow.

For many applications, a conventional air lock is sufficient. However, air ducts (e.g., with exhaust valves, supply valves, indoor balancing systems, etc.) used in certain critical indoor environments require accurate control of the airflow, particularly when the static pressure in the duct system is high, small movements of the vane gate can cause significant changes in the airflow. When conventional damper blades are rotated from an initial closed position to a slightly open position, there is a tendency for a large amount of air to be immediately allowed to pass through the damper region, and this volume is relatively uncontrolled. When the static pressure in the pipe system is high, even small movements of the blade brake may result in significant changes in the airflow. Controlling the blade using an actuator is not sufficient to produce a movement small enough to maintain proper control. It is desirable to have damper blades that allow more controlled air flow at a position that is nearly closed (or nearly open); i.e. at lower airflow requirements and even more so at higher pressures.

It is further desirable to have an airflow sensor that is independent of airflow orientation in order to allow the sensor to be positioned closer to a bend in the air duct than a conventional sensor can be positioned. It would be desirable to have an airflow sensor that is not susceptible to clogging.

Disclosure of Invention

One embodiment of the present disclosure is an air brake assembly for an air duct having an inner wall and an outer wall. The air brake assembly includes an air brake plate having a perimeter and a plurality of teeth spaced at least partially around and extending from the perimeter. The plurality of teeth vary in length around the perimeter from a maximum value to a minimum value over a span of about 90 degrees. The air brake assembly further includes a bridge shaft assembly fixedly coupled to the air brake plate and rotatably coupled to the air duct. Rotation of the axle assembly rotates the damper plate within the air duct between a fully open position and a fully closed position to increase or decrease the flow of fluid through the air duct.

In some embodiments, the air brake panel comprises: a first airfoil member having a plurality of teeth made of a first material; and a second blade profile member having a plurality of teeth made of a second material having a greater stiffness than the first material. In other embodiments, the air brake plate further comprises a third blade member having a plurality of teeth made of a third material having a greater stiffness than the second material.

In some embodiments, each of the teeth includes a resilient portion and a flexible portion proximate the perimeter. The resilient portion has a greater stiffness than the flexible portion.

In some embodiments, the damper panel includes a gasket configured to contact an inner wall of the air duct when the damper panel is in the fully closed position.

In some embodiments, a portion of the plurality of teeth contacts an inner wall of the air duct when the damper panel is in the fully closed position. In some embodiments, a portion of the plurality of teeth contacts an inner wall of the air duct when the damper panel is in the partially closed position.

In some embodiments, a portion of the plurality of teeth is made of polytetrafluoroethylene (Teflon). In some embodiments, a portion of the plurality of teeth is made of metal with a plastic coating.

In some embodiments, the axle shaft assembly includes a first shaft member and a second shaft member. Each of the first and second shaft members includes a slot configured to receive the damper plate.

In some embodiments, the axle shaft assembly includes a shaft member configured to be fastened to the air brake plate using a bracket component and a plurality of rivets.

In some embodiments, the air brake assembly includes an air brake control assembly configured to drive rotation of the axle shaft assembly. In other embodiments, the damper control assembly includes a pressure sensor, a motor, and an actuator.

Another embodiment of the present disclosure is a method for controlling fluid flow through an air duct. The method comprises the following steps: the method includes receiving a target airflow setting, receiving an airflow measurement from a pressure sensor, and generating a command to rotate the damper panel to a position setting between a fully open position and a fully closed position based at least in part on the target airflow setting and the airflow measurement. The air brake panel has a perimeter and a plurality of teeth spaced at least partially around and extending from the perimeter. The plurality of teeth vary in length around the perimeter from a maximum value to a minimum value over a span of about 90 degrees. The method further includes driving the damper panel to the position setting.

Yet another embodiment of the present disclosure is a method of providing an air brake assembly for an air duct having an inner wall and an outer wall. The method includes providing an air brake assembly including an air brake plate having a perimeter and a plurality of teeth spaced at least partially around and extending from the perimeter. The plurality of teeth vary in length around the perimeter from a maximum value to a minimum value over a span of about 90 degrees. The method further includes providing a bridge shaft assembly fixedly coupled to the damper plate and rotatably coupled to the air duct. Rotation of the axle assembly rotates the damper plate within the air duct between a fully open position and a fully closed position to increase or decrease the flow of fluid through the air duct.

Another embodiment of the present disclosure is an airflow sensor assembly for an air duct. The air flow sensor assembly includes an air duct having an inner wall and an outer wall, a high pressure detection device, and a low pressure detection device. The low pressure detection device includes a hollow ring disposed within an inner wall of the air duct. The hollow ring includes an inner peripheral portion, an outer peripheral portion, and a first set of apertures defined in the hollow ring. The first set of apertures are spaced around an inner peripheral portion of the hollow ring. The airflow sensor assembly further includes a pressure sensor fluidly coupled to the high pressure detection device and the low pressure detection device.

In some embodiments, wherein the low pressure detection device comprises: a first connection opening provided in an outer peripheral portion of the hollow ring; and a first tube fluidly coupled to the first connection opening. In other embodiments, the high voltage detection apparatus includes: a second set of apertures defined in the high pressure detection device and spaced around an inner periphery of the air duct; a gasket having a recessed area defined therein and a second connection opening, the gasket being fitted on the outer wall and proximate the second plurality of apertures; and a second tube fluidly coupled to the second connection opening. In further embodiments, the pressure sensor is fluidly coupled to the first tube and the second tube. In yet further embodiments, the airflow sensor assembly includes a gasket protection ring configured to fit over an outer surface of the gasket.

In some embodiments, the air flow sensor assembly includes an air brake control assembly communicatively coupled to the pressure sensor. In other embodiments, the damper control assembly includes an air damper assembly, a motor, and an actuator.

In some embodiments, each of the first set of apertures is orthogonal to a direction of airflow through the air duct.

In some embodiments, the hollow ring has an outer diameter in the range of 0.5 inches to 0.75 inches.

Another embodiment of the present disclosure is an airflow sensor assembly for an air duct. The air flow sensor assembly includes an air duct having an inner wall and an outer wall, a high pressure detection device, and a low pressure detection device. The low pressure detection device includes: an air flow restrictor; a first set of apertures defined in the low pressure detection device and spaced around a perimeter of the air duct; a first gasket having a recessed region defined therein; a first connection opening. The first gasket is mounted on the outer wall and adjacent the first plurality of apertures and the airflow restrictor. The low pressure detection device further includes a first tube fluidly coupled to the first connection opening. The airflow sensor assembly further includes a pressure sensor fluidly coupled to the high pressure detection device and the low pressure detection device.

In some embodiments, the airflow restrictor includes a shroud component coupled with an inner wall of the air duct. In other embodiments, the air flow restrictor comprises a channel disposed in an inner wall of the air duct.

In some embodiments, the high voltage detection apparatus includes: a second set of apertures defined in the high pressure detection device and spaced around an inner periphery of the air duct; a gasket having a recessed area defined therein and a second connection opening, the gasket being fitted on the outer wall and proximate the second plurality of apertures; and a second tube fluidly coupled to the second connection opening. In other embodiments, the pressure sensor is fluidly coupled to the first tube and the second tube.

In some embodiments, the air flow sensor assembly includes one or more gasket protection rings configured to fit over at least one of an outer surface of the first gasket or an outer surface of the second gasket.

Yet another embodiment of the present disclosure is a method of sensing airflow in an air duct. The method includes receiving a high pressure measurement from a high pressure detection device and receiving a low pressure measurement from a low pressure detection device. The low pressure detection device includes a hollow ring disposed within an inner wall of the air duct. The hollow ring includes an inner peripheral portion, an outer peripheral portion, and a first set of apertures defined in the hollow ring. The first set of apertures are spaced around an inner peripheral portion of the hollow ring. The low pressure detection device further includes: a first connection opening provided in an outer peripheral portion of the hollow ring; and a first tube fluidly coupled to the first connection opening. The method further includes calculating an air velocity through the duct based on the high air pressure measurement and the low air pressure measurement.

In some embodiments, the high voltage detection apparatus includes: a second set of apertures defined in the high pressure detection device and spaced around an inner periphery of the air duct; a gasket having a recessed area defined therein and a second connection opening, the gasket being fitted on the outer wall and proximate the second plurality of apertures; and a second tube fluidly coupled to the second connection opening.

Those skilled in the art will recognize that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices and/or processes described herein, as defined solely by the claims, will become apparent in the detailed description set forth herein when taken in conjunction with the accompanying drawings.

Drawings

The accompanying drawings, in which like reference numerals refer to the same or similar parts throughout the several views, disclose exemplary embodiments, and wherein:

FIG. 1 is an isometric view of an air duct assembly according to some embodiments.

FIG. 2 is an exploded isometric view of an air brake assembly that may be used in the air duct assembly of FIG. 1, according to some embodiments.

Fig. 3 is a front view of the air brake assembly of fig. 2 in accordance with some embodiments.

Fig. 4 is a side view of the air brake assembly of fig. 2 in accordance with some embodiments.

Fig. 5 is a rear view of the air brake assembly of fig. 2 in accordance with some embodiments.

FIG. 6 is a side cross-sectional view of a shaft arrangement that may be used in the air brake assembly of FIG. 2, according to some embodiments.

FIG. 7 is a side cross-sectional view of another shaft arrangement that may be used in the air brake assembly of FIG. 2 in accordance with some embodiments.

FIG. 8 is a side cross-sectional view of the air duct assembly of FIG. 1, according to some embodiments.

FIG. 9 is a detailed cross-sectional view of the air brake assembly of FIG. 2 depicted in a partially closed position in accordance with some embodiments.

FIG. 10 is a detailed side cross-sectional view of the air brake assembly of FIG. 2 depicted in a fully closed position in accordance with some embodiments.

FIG. 11 is a front view of another air brake assembly that may be used in the air duct assembly of FIG. 1 according to some embodiments.

FIG. 12 is a side view of the air brake assembly of FIG. 11 according to some embodiments.

FIG. 13 is a side view of another air brake assembly that may be used in the air duct assembly of FIG. 1 according to some embodiments.

FIG. 14 is an exploded isometric view of another air brake assembly that may be used in the air duct assembly of FIG. 1, according to some embodiments.

FIG. 15 is a detailed view of another air brake assembly that may be used in the air duct assembly of FIG. 1 according to some embodiments.

FIG. 16 is a side cross-sectional view of an air duct airflow sensor assembly according to some embodiments.

FIG. 17 is a side cross-sectional view of the air duct assembly of FIG. 1, according to some embodiments.

Fig. 18 is a top view of the air duct assembly of fig. 1, according to some embodiments.

FIG. 19 is an exploded perspective view of an air duct, ring, and gasket assembly that may be used in the air duct assembly of FIG. 1, according to some embodiments.

FIG. 20 is another top view of the air duct assembly of FIG. 1 according to some embodiments.

FIG. 21 is a side cross-sectional view of an air duct assembly taken along line B-B of FIG. 20, according to some embodiments.

Fig. 22 is a detailed view C-C of a joint, washer, and tube according to some embodiments.

Fig. 23 is a detailed view D-D of a gasket according to some embodiments.

FIG. 24 is a side cross-sectional view of another air duct airflow sensor assembly according to some embodiments.

FIG. 25 is a side cross-sectional view of another air duct airflow sensor assembly according to some embodiments.

Detailed Description

The drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, degree, etc.) together with the specification, unless otherwise indicated, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms "horizontal," "vertical," "left," "right," "upper" and "lower," as well as adjectives and adverb derivatives thereof (e.g., "horizontally," "upwardly," etc.) simply refer to the orientation of the structure as it appears when the particular drawing figure is oriented toward the reader. Similarly, the terms "inwardly" and "outwardly" generally refer to the direction of a surface relative to its axis of elongation or axis of rotation, as the case may be.

Fig. 1 depicts an isometric view of a cylindrical air duct assembly 1. As shown, the air duct assembly 1 includes a first end 2, a second end 3, an inner wall 4, an outer wall 5, and a control assembly 100. In some embodiments, the air duct assembly 1 may be placed such that air flows from the first end 2 to the second end 3. The air duct assembly 1 is further shown as including an air brake assembly 10 disposed within the inner wall 4.

Referring now to fig. 2-5, several views of the air brake assembly 10 are provided. Fig. 2 depicts an exploded isometric view, fig. 3 depicts a front view, fig. 4 depicts a side view, and fig. 5 depicts a rear view. The air brake assembly 10 is shown to include, among other things, a first air brake flap 12 and a second air brake flap 14. The first airflow member includes a first section 18 and a second section 20. In the exemplary embodiment, first section 18 and second section 20 are fabricated from a substantially rigid material, such as, but not limited to, metal, polymer, ceramic, wood, a coating material, a laminate, and the like. Each section includes a straight portion 22 and a curved portion 24.

A plurality of fingers 30 are shown extending outwardly from and at least partially around the curved peripheral portion of each section 18, 20. In one exemplary embodiment, the fingers 30 may be integrally formed with the sections 18, 20. In another exemplary embodiment, the fingers 30 may be separate and mounted or attached to at least a portion of each section 18, 20. In the exemplary embodiment, fingers 30 are formed from a relatively resilient material. In exemplary embodiments, the material may be metal, resilient plastic, or other generally resilient material. In some embodiments, the fingers 30 are made of metal or other resilient material that is covered or coated with plastic or other material that does not significantly scratch the inner wall of the air duct. In other embodiments, the fingers 30 are made of a single material that is both resilient and does not significantly scratch the inner wall of the air duct.

The fingers 30 may be sized to have a smaller length near the straight portion 22 and increase in length near the midpoint of the curved portion 24. In other words, in such an exemplary embodiment, the length of the finger 30 varies from a maximum value to a minimum value over a span of about 90 degrees around the perimeter. For example, referring specifically to fig. 2, fingers 31-33 (where finger 31 is longer than finger 32 or 33) are longer than fingers 34-36 (where finger 34 is longer than finger 35 or 36). In the exemplary embodiment, second section 20 of airfoil member 16 is configured to mirror first section 18 and has fingers 30 that are sized and configured similarly to those associated with first section 18.

In the exemplary embodiment, second blade form member includes a first section 42 and a second section 44. In the exemplary embodiment, first section 42 and second section 44 are fabricated from a substantially rigid material, such as, but not limited to, a metal (e.g., aluminum), a polymer, a ceramic, wood, a coating material, a laminate, and the like. In some embodiments, first section 42 and second section 44 are made of a different material than first section 18 and second section 20. For example, first section 42 and second section 44 may be made of a material having a lower hardness than the material of first section 18 and second section 20. In other embodiments, first section 42 and second section 44 are made of the same material as first section 18 and second section 20. Each section 42, 44 is shown to include a straight portion 46 and a curved portion 48.

Multiple fingersThe shape 50 extends outwardly from and at least partially around the curved peripheral portion of each section 42, 44. In one exemplary embodiment, the fingers 50 may be integrally formed with the sections 42, 44. In another exemplary embodiment, the fingers 50 may be separate and mounted or attached to at least a portion of each section 42, 44. In the exemplary embodiment, fingers 50 are formed from a material that is more flexible than the material from which fingers 30 are formed. In exemplary embodiments, the material may be a flexible metal, plastic, fabric, laminate, or other material that has some degree of curvature but is capable of returning to an unbent position. In one exemplary embodiment, the material may be polytetrafluoroethyleneSimilar to the fingers 30, in some embodiments, the fingers 50 are sized to have a smaller length near the straight portion 46 and increase in length near the midpoint of the curved portion 48. For example, fingers 51-53 (where finger 51 is longer than fingers 52 or 53) are longer than fingers 54-56 (where finger 54 is longer than fingers 55 or 56).

In the exemplary embodiment, second section 44 is configured to mirror first section 42 and has fingers 50 that are similarly sized and configured as those associated with first section 42. In an exemplary embodiment, the fingers 50 may be sized to be slightly longer and/or slightly larger than the corresponding mating adjacent fingers 30 (i.e., the fingers 31 are adjacent to the fingers 51 when the first and second blade form members are assembled and the fingers 30 are generally adjacent to the fingers 50). This may be done so that when the damper 10 is in the closed position, the resilient fingers 30 are close to but do not (or hardly) contact the inner wall 4 of the air duct 1, which will avoid or reduce the possibility of the inner wall 4 being scratched by the resilient fingers 30. In an alternative exemplary embodiment, the fingers 30 are slightly offset from the corresponding fingers 50.

The first and second air brake panels 12, 14 may be connected to one another with the first and second blade form members comprising sections 18, 20, 42, 44 sandwiched therebetween such that on one side of the air brake, the fingers 50 are shown on the upper half and the fingers 30 are shown on the lower half, with the opposite on the other side of the air brake. In some embodiments, the sections 18, 20, 42, 44 may be coupled to each other and to the damper panels 12, 14 using rivets 58. In other embodiments, any other suitable fastening mechanism (e.g., bolts, screws, adhesives) may be utilized to couple the sections 18, 20, 42, 44 and the air brake panels 12, 14. In some embodiments, the first air brake flap 12 and the second air brake flap 14 may be connected to each other and the axle shaft assembly 70 connected to these air brake flaps using one or more bolts 82 and lock nuts 84. It should be understood that other fastening mechanisms known to those skilled in the art may be used.

In exemplary embodiments, an optional gasket 60 may be disposed between the first air brake flap 12 and the second air brake flap 14 and adjacent the first section 42 and the second section 44 of the second blade form member (when assembled). An optional gasket 60 may be used to seal the air flow through the air duct assembly 1. In various embodiments, the optional gasket may be made of rubber, silicone, neoprene, plastic polymer, or any other suitable gasket material.

The axle shaft assembly 70 may comprise a single piece or, in an exemplary embodiment, may comprise a first member 72 and a second member 74. In an exemplary embodiment, the first member 72 may be longer than the second member 74. As described in more detail below with reference to fig. 8, this may be because the first member 72 is configured to couple with a motor within the control assembly 100 of the air duct damper assembly 1. In some embodiments, each shaft member 72, 74 may include a split shaft sized to fit over the assembled first and second air brake flaps 12, 14 and first and second vane members, as shown in fig. 3-5. In other words, each shaft member 72, 74 may include a slot to receive the assembled air brake flap 12, 14 and blade form member. In an exemplary embodiment, a rotating bushing 76 and a stationary bushing 78 may be fitted over each shaft member 72, 74 to ensure that the air brake assembly 10 is free to rotate within the air duct assembly 1. In some embodiments, an O-ring 80 may also be fitted over each shaft member 72, 74.

Referring now to fig. 6 and 7, a cross-sectional view of an embodiment of the axle assembly 70, the damper panels 12, 14, and the junctions between the sections 18, 20, 42, 44 is depicted. For example, as depicted in fig. 6, the sections 18, 20, 42, and 44 may be held between the air brake panels 12 and 14 using split shaft members 72, 74. In various embodiments, rivets 58 passing through split shaft members 72, 72 are used to secure split shaft members 72, 74 and to maintain sections 18, 20, 42, and 44 and air brake panels 12 and 14 in a stacked configuration. In other embodiments, another type of fastener may be used instead of rivet 58.

Referring now to fig. 7, an alternative joint embodiment is depicted. As shown, solid shafts 86 may be used in the axle shaft assembly 70 instead of split shaft members 72, 74. Solid shaft 86 may be held in a stacked configuration on sections 18, 20, 42, 44 and air brake panels 12, 14 using U-brackets 88 and rivets 58. The U-shaped bracket 88 may have any suitable geometry required to maintain the solid shaft 86 in the stacked configuration. In various embodiments, another type of fastener may be used instead of rivet 58. As shown, the solid shaft 86 may be coupled flush with the damper panel 12. In other embodiments, a symmetrical configuration may be utilized and the solid shaft 86 may be coupled flush with the air brake flap 14.

Referring now to FIG. 8, a side cross-sectional view of the damper assembly 10 installed in the air duct assembly 1 is shown. Axle shaft assembly shaft member 74 may be positioned in an aperture 90 at the bottom of the air duct and shaft member 72 may be positioned in an aperture 92 at the top of the air duct, proximate to control assembly 100. The control assembly 100 may have a housing 102. The housing 102 may house an electrical power supply 104, a gear/motor 106, an actuator 108, a control panel 110, a pressure sensor 112, a low voltage pickup 114, and a high voltage pickup 116. The pickups 114, 116 are in communication with a pressure sensor mechanism inside the air duct 1, such as a mechanism (not shown) known to those skilled in the art.

In operation, an operator may provide a target airflow set point. The pressure sensor 112 may provide information regarding the current actual airflow calculated from the high pressure pickup 114 and the low pressure pickup 116. The high pressure pickup 114 and the low pressure pickup 116 may sense the air pressure in the air duct flowing from the first end 2 to the second end 3 of the air duct 1. The damper 10 can be moved to set the value and the actual air flow balance. The airflow set point signal and the measured airflow signal may be received by a control panel 110 that generates a position set point signal that is sent to the power supply 104, which in turn actuates the motor 106. The motor 106 is operatively associated with the axle assembly shaft member 72 to rotate it between the fully open and fully closed positions as desired.

Referring now to fig. 9 and 10, detailed cross-sectional views of the air brake assembly 10 in the partially closed position and the fully closed position, respectively, are depicted. When the air brake assembly 10 is rotated toward the closed position, as specifically depicted in fig. 9, the fingers 50 and washers 60 are proximate the inner wall 4. In so doing, the air flow is reduced, but not completely reduced. The gap 120 between the fingers 50 allows air to flow through until the air brake 10 is rotated to the fully closed position, in which case the fingers 50 (all or at least a portion thereof) may flex such that a majority of the length or at least a portion of the planar surface of the fingers 50 contacts the inner wall 4, as shown in fig. 10. The larger the portion of the finger 50 that contacts the inner wall 4, the smaller the gap 120 and the smaller the amount of air that can flow through the damper.

The presently disclosed damper is characterized by the vane member providing greater air pressure control and resolution as the damper 10 and fingers 50 approach full closure. Because current designs do not require acceleration of air flow through the vortex generators (such as those available from Accoutrol ^TM Those vortex generators used in the conventional airlock products obtained) and thus higher flow rates can be obtained.

Referring now to fig. 11 and 12, another embodiment of an air brake assembly 300 is depicted. The air brake assembly 300 may include a single plate instead of the first and second air brake plates of the air brake assembly 10 described above. The damper assembly 300 may have two rows of fingers 302, 303 attached to the periphery of the damper assembly 300 by fasteners 304. In another exemplary embodiment depicted in fig. 13, the air brake assembly 400 may have a single row of multiple fingers 402 attached to the periphery of the air brake assembly 400 by fasteners 404.

In another alternative embodiment, the damper may have more than two rows of fingers. In one such embodiment depicted in fig. 14, the damper 500 is shown as having three rows of fingers. Three rows of fingers may be implemented by combining a first profile (made up of first section 18 and second section 20), a second profile (made up of first section 42 and second section 44), and a third profile 502 (made up of first section 504 and second section 506). In some embodiments, the fingers of the sections 504 and 506 of the third airfoil 502 have a greater stiffness than the fingers of the sections 18, 20, 42, 44. In other embodiments, one or more of sections 18, 20, 42, and 44 have a greater or equivalent stiffness than sections 504 and 506.

Referring now to fig. 15, a detailed view of another embodiment of an air brake assembly 600 is depicted. The air brake assembly 600 may include teeth made of one or more materials having different rigidities. For example, each tooth 602 may have a relatively resilient or rigid portion 604 near the base 606 and a relatively flexible portion 608 near the distal end 610 of the tooth 602.

Referring now to fig. 16-23, various views depicting an air duct airflow sensor assembly 1000 according to some embodiments are shown. Air may flow through the air duct airflow sensor assembly 1000 in the direction indicated by arrow "a" as shown in fig. 16. The air duct airflow sensor assembly 1000 includes a low pressure detection device and a high pressure detection device. The low pressure detection means comprises a hollow ring 1020 mounted to or otherwise associated with the inner wall 4. In some embodiments, the outer diameter of the hollow ring 1020 may be in the range of 0.5 inches to 0.75 inches. In an exemplary embodiment, the outer diameter of the hollow ring 1020 is 0.625 inches. The ring 1020 has a plurality of apertures 1022 defined in an inner periphery 1023 (relative to an outer periphery 1024 proximate the inner wall 4) of the ring. In the exemplary embodiment, apertures 1022 are disposed in an inner perimeter of ring 1020 such that they are generally orthogonal to an orientation of the airflow such that the airflow passes through apertures 1022, rather than flowing into apertures 1022.

The hollow connector fitting 1028 connects to an aperture defined in the ring 1020 and an aperture defined in the pipe 1. The tube 1032 is connected to a joint 1028. Air flowing into the orifice 1022 may flow through the ring 1020, into the fitting 1028, and through the tube 1032. The tube 1032 is connected to a pressure sensor 1034 such that air flowing through the tube 1032 is received and detected by the flow pressure sensor 1034. Loop 1020 serves two purposes: as an air collection device and as an air flow restriction barrier to create a measurable pressure differential.

The air duct 1 further comprises a plurality of apertures 1040 defined therein, the apertures 1040 being arranged generally in an annular shape around the inner wall 4. A gasket 1042 is associated with the outer wall 5 and is generally located above the aperture 1040. The gasket 1042 has a recessed region 1043 such that when associated with the outer wall 5, a chamber 1043 is formed. Detailed views of the orifice 1040 and the chamber 1043 are specifically depicted in fig. 22 and 23.

The hollow connector fitting 1044 is connected to a washer 1042. In an exemplary embodiment, a gasket protection ring 1045 may be used and fitted over the gasket 1042. The pipe 1046 is connected to the joint 1044. The tube 1046 is connected to the pressure sensor 1034. In alternative exemplary embodiments, a separate pressure sensor (not shown) may be connected to the tube 1046. The orifice 1040, gasket 1042, fitting 1044, tubing 1046, and pressure sensor 1034 form a high pressure sensor detection device.

In the exemplary embodiment, pressure sensor 1034 is part of a control assembly 1006 that controls the opening and closing of air brake 1050. In one exemplary embodiment of a control assembly, particularly depicted in fig. 21, a housing 1100 is mounted to or otherwise associated with an air duct. The sensor 1034, processor 1102, actuator 1104, and power supply 1106 may be disposed within the housing 1100. The air lock 1050 is in operative communication with the actuator 1104.

In operation, air flowing through the duct 1 in the direction of arrow a first encounters the high pressure detection orifice 1040. A portion of the air enters the aperture 1040 and flows into the chamber 1043. The air then moves into the tubular 1046 via the joint 1044 and then into the pressure sensor 1034. The pressure detected is the "high" pressure in the conduit 1, i.e. the pressure upstream of the air flow restrictor (i.e. the loop 1020).

Air flowing through the pipe 1 then flows through the ring 1020 and may enter the orifice 1022 and travel through the fitting 1028 and the tube 1032 and into the pressure sensor 1034. The pressure detected is the "low" pressure in the conduit, i.e., the pressure at the point where the gas flow is limited by the loop 1020. The difference between the high pressure measurement and the low pressure measurement is an indication of the air velocity through the duct, in particular the scaled square root of the measured pressure (i.e. application of the bernoulli principle). The sensor 1034 may send a signal to the control assembly 1006, which in turn may rotate the damper 1050 to open or close the air duct 1.

In the exemplary embodiment, pressure sensor 1034 is a "dead end" pressure sensor (relative to a flow-through sensor); that is, after the initial pressure builds, no additional airflow passes through the sensor. This may reduce the chance of the orifices 1022 and 1040 being plugged.

In one exemplary embodiment, for an air duct having a diameter of 10 inches, a 0.5 inch diameter ring 1020 is used. With this configuration, a line static pressure of 0.1in Wg can be used to obtain measurements from 850CFM (cubic feet per minute) down to 35 CFM. In other embodiments, a 0.625 inch diameter ring 1020 may be utilized.

The benefit of the presently described sensor assembly is that, because of the design of the ring 1020 with the apertures 1022 oriented orthogonal to the air flow, the air to be diverted into the ring 1020 flows through the apertures 1022, rather than directly into the apertures 1022. This may reduce the likelihood of the orifices 1022 becoming clogged with dust, dirt, and debris associated with the airflow.

Another benefit is that the presently disclosed apparatus is not dependent on airflow orientation. Typically, conventional pressure sensor devices, such as variable air volume ("VAV") boxes, rely on airflow orientation and have bends or other transitions in the duct in general areas where the sensor may cause inaccurate measurements due to naturally occurring airflow discontinuities in the vicinity of the bends. With the air detection device of the presently disclosed apparatus (which is independent of airflow orientation), the sensor assembly may be located closer to bends or other transitions in the air duct without affecting pressure measurements. This provides a piping designer with greater flexibility in designing the placement of the valve assembly.

Another benefit of the presently described sensor assembly is that it presents minimal obstruction to airflow and thus allows for greater CFM speeds at lower duct static forces. Additionally, in the event that any one of the orifices 1022 is plugged, periodic maintenance is readily effectuated by disconnecting the sensor 1034 and introducing a stream of compressed air into the tubular 1032 or tubular 1046. Any clogged debris will blow out of the orifices 1022 or 1040, respectively.

Another benefit of the presently described sensor assembly as part of the overall sensor/controller/damper design is that it can operate at 0-10V control signals to provide the desired airflow. This allows a designer or operator to set the desired CFM using linear control signals from the control system.

Referring now to fig. 24 and 25, an alternative embodiment of airflow restriction for use in a low pressure detection device is depicted. Specifically, FIG. 24 depicts an airflow sensor assembly that includes a shroud component 1060. In some embodiments, the shroud component 1060 may be annular in shape, having an inner wall attachment portion 1062, an angled portion 1064, and an aperture blocking portion 1066, although any suitable shroud configuration or geometry may be utilized. In some embodiments, the orifice shielding portion 1066 extends a distance of 0.5 inches to 0.75 inches from the inner wall 4.

The orifice shielding portion 1066 is placed close to the orifice 1022 provided in the air duct 1. A gasket 1048 is associated with the outer wall 5 and generally above the aperture 1022. In some embodiments, one or more gasket protection rings (not shown) may be used and fitted over the gaskets 1042, 1048. The gasket 1048 has a recessed region 1049 such that when associated with the outer wall 5, a chamber 1049 is formed. Air flowing through the duct 1 flows through the inner wall attachment portion 1062, the angled portion 1064, and the aperture blocking portion 1066 of the shroud component 1060 and may enter the aperture 1022. The air may then travel through the chamber 1049 into the joint 1028. Similar to the pressure measurement process described above with reference to fig. 16-23, after passing through the fitting 1028, air may travel through the tubular and into the pressure sensor for controlling the air brake assembly.

Turning now to fig. 25, an airflow sensor assembly including a channel feature 1070 is depicted. Similar to the shroud component 1060 described above with reference to fig. 24, the channel feature 1070 may be used as an air restriction feature in place of the hollow ring 1020 described above with reference to fig. 16-23. The channel feature 1070 may include a plurality of apertures 1022 distributed about the perimeter of the channel feature 1070. In some embodiments, the depth of channel feature 1070 may be in the range of 0.5 inches to 0.75 inches. In an exemplary embodiment, the depth of channel feature 1070 is 0.625 inches. In other words, if the air duct 1 is nominally 10 inches in diameter, the diameter may extend to 11.25 inches in the region of the channel feature 1070.

A gasket 1048 is associated with the outer wall 5 and generally above the aperture 1022. In some embodiments, one or more gasket protection rings (not shown) may be used and fitted over the gaskets 1042, 1048. The gasket 1048 has a recessed region 1049 such that when associated with the outer wall 5, a chamber 1049 is formed. Air flowing through conduit 1 flows through channel feature 1070 and may enter orifice 1022. The air may then travel through the chamber 1049 into the joint 1028. Similar to the pressure measurement process described above with reference to fig. 16-23, after passing through the fitting 1028, air may travel through the tubular and into the pressure sensor for controlling the air brake assembly.

The above description of exemplary embodiments of an air lock may be used in an air duct. It should be understood that the damper of the present disclosure may also be used with pipes configured to convey other fluids, such as, but not limited to, gases and liquids.

The present invention also relates to a damper system comprising a duct, a damper according to the damper embodiments disclosed above and mounted in the duct, and a control assembly adapted to rotate the damper from an open position to a closed position.

As used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

"optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

Throughout the description and claims of this specification, the word "comprise" and variations of the word such as "comprises" and "comprising" means "including but not limited to", and is not intended to exclude, for example, other additives, components, integers or steps. "exemplary" refers to "an example thereof, and is not intended to convey an indication of a preferred or ideal embodiment. "such as" is not used in a limiting sense, but for explanatory purposes.

Components are disclosed that can be used to perform the disclosed methods, apparatuses, and systems. These and other components are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these components are disclosed that while specific reference of each various individual and collective combinations and permutation of these may not be explicitly disclosed, each is specifically contemplated and described herein for all methods, apparatus, and systems. This applies to all aspects of the present application including, but not limited to, steps in the disclosed methods. Thus, if there are a plurality of additional steps that can be performed, it should be understood that each of these additional steps can be performed with any particular embodiment or combination of embodiments of the disclosed methods.

It should be further noted that any patents, applications, and publications cited herein are incorporated by reference in their entirety.

Claims

1. An air brake assembly for an air duct, the air brake assembly comprising:

an airflow member, the airflow member comprising:

a first section having a first peripheral edge, and

a second section having a second peripheral edge;

a plurality of first flexible protrusions spaced at least partially around and extending from the first peripheral edge, the first flexible protrusions providing a plurality of first voids between adjacent ones of the first flexible protrusions at least partially around the first peripheral edge; and

a plurality of second flexible protrusions spaced at least partially around and extending from the second peripheral edge, the second flexible protrusions providing a plurality of second voids between adjacent ones of the second flexible protrusions at least partially around the second peripheral edge;

a gasket, the gasket comprising:

a first side cooperating with the first section, and

a second side opposite the first side, the second side cooperating with the second section;

A first air brake flap coupled to the first section; and

a bridge shaft assembly coupled to the first air brake flap.

2. The air brake assembly of claim 1 wherein:

the axle shaft assembly is centered on an axis;

the first peripheral edge is disposed on a first plane;

the second peripheral edge is disposed on a second plane parallel to the first plane;

the axis is arranged on a third plane orthogonal to the first plane; and

the airflow member is configured such that the third plane extends between the first flexible protrusion and the second flexible protrusion.

3. The air brake assembly of claim 1 wherein:

the first peripheral edge is disposed on a first plane;

the second peripheral edge is disposed on a second plane parallel to the first plane; and

the airflow member is configured such that the first section does not overlap the second section in a direction perpendicular to the first plane.

4. The air brake assembly of claim 1 wherein:

the axle assembly is centered about a first axis;

the first section includes:

a first straight portion extending along a second axis parallel to or coincident with the first axis, an

A first curved portion extending from a first end of the first straight portion to a second end of the first straight portion.

5. The air brake assembly of claim 4 wherein said second section comprises:

a second straight portion extending along a third axis parallel to or coincident with the first axis, an

A second curved portion extending from a first end of the second straight portion to a second end of the second straight portion.

6. The air brake assembly of claim 1 wherein said first section, said second section and said washer are configured such that when said air brake assembly is rotated in a first rotational direction, said first section tracks a first portion of said washer and a second section tracks a second portion of said washer.

7. The air brake assembly according to claim 1 further comprising a second air brake flap coupled to said second section;

wherein the first section extends between the first air brake flap and the second air brake flap; and

wherein the second section extends between the second air brake flap and the first air brake flap.

8. The air brake assembly according to claim 1 further comprising a second air brake flap coupled to said second section;

wherein the gasket is placed between the first section and the second air brake plate; and

wherein the gasket is disposed between the second section and the first air brake flap.

9. The air brake assembly of claim 1 wherein:

the gasket having a third peripheral edge; and

the first air brake flap has a fourth peripheral edge disposed radially inward from the third peripheral edge.

10. The air brake assembly of claim 1 wherein said first section is a mirror image of said second section.

11. The air brake assembly of claim 1 wherein:

the axle assembly includes a first member having a first slot;

the first air brake flap and the gasket are disposed within the first slot;

the axle assembly further includes a second member having a second slot; and

the first air brake flap and the gasket are disposed within the second slot.

12. A method of controlling the flow of a fluid through an air duct, the method comprising:

receiving a target air flow set value;

Receiving an airflow measurement from a pressure sensor;

generating a command for rotating an airflow member about an axis to a position set point between a fully open position and a fully closed position based at least in part on the target airflow set point and the airflow measurement, wherein the airflow member has a first section, a second section, a plurality of first flexible protrusions, and a plurality of second flexible protrusions, the first section having a first peripheral edge, the second section having a second peripheral edge, the first flexible protrusions being at least partially spaced about and extending from the first peripheral edge, the second flexible protrusions being at least partially spaced about and extending from the second peripheral edge, wherein the first section is coupled to a first air brake plate, wherein the second section is coupled to a second air brake plate, wherein a gasket is placed between the first section and the second air brake plate and between the second section and the first air brake plate; and

the airflow member is driven to the position set point.

13. The method of claim 12, wherein:

Rotating the airflow member includes rotating a bridge shaft assembly of the airflow member, the bridge shaft assembly centered about a first axis; and is also provided with

The first section includes:

14. The method of claim 12, wherein the first section, the second section, and the gasket are configured such that, when the airflow member rotates in a first rotational direction, the first section tracks a first portion of the gasket and a second section tracks a second portion of the gasket.

15. An air duct assembly comprising:

an air duct, the air duct comprising an inner surface; and

an air brake assembly, the air brake assembly comprising:

an airflow member, the airflow member comprising:

a first section having a first peripheral edge, and

a second section having a second peripheral edge;

a gasket, the gasket comprising:

a first side cooperating with the first section, and

a first air brake flap coupled to the first section; and

a bridge shaft assembly coupled to the first air brake flap and rotationally coupled with the air duct;

wherein rotation of the axle assembly causes the first flexible tab to contact the inner surface, the washer to contact the inner surface, and the first flexible tab to contact the inner surface.

16. The air duct assembly of claim 15, wherein:

the axle shaft assembly is centered on an axis;

the first peripheral edge is disposed on a first plane;

the axis is arranged on a third plane orthogonal to the first plane; and

17. The air duct assembly of claim 15, wherein:

the first peripheral edge is disposed on a first plane;

18. The air duct assembly of claim 15, wherein:

the axle assembly is centered about a first axis;

the first section includes:

19. The air duct assembly of claim 18, wherein the second section comprises:

20. The air duct assembly of claim 15, wherein the first section, the second section, and the gasket are configured such that, when the air brake assembly is rotated in a first rotational direction, the first section tracks a first portion of the gasket and a second section tracks a second portion of the gasket.

21. An airflow sensor assembly for an air duct having an inner wall and an outer wall;

the airflow sensor assembly includes:

a high voltage detection device;

a low pressure detection device, the low pressure detection device comprising:

a hollow ring configured to be disposed within an inner wall of the air duct, the hollow ring having an inner peripheral portion and an outer peripheral portion; and

a first plurality of apertures defined in the low pressure detection device and spaced about an inner peripheral portion of the hollow ring; and

a pressure sensor configured to be fluidly coupled to the high pressure detection device and the low pressure detection device.

22. The airflow sensor assembly of claim 21, wherein said low pressure detection device further comprises:

a first connection opening provided in an outer peripheral portion of the hollow ring; and

a first tube fluidly coupled to the first connection opening.

23. The airflow sensor assembly of claim 22, wherein said high pressure sensing means comprises:

a second plurality of apertures defined in the high pressure detection device and spaced around an inner periphery of the air duct;

a gasket having a recessed area defined therein and a second connection opening, the gasket being fitted on the outer wall and proximate the second plurality of apertures; and

a second tube fluidly coupled to the second connection opening.

24. The airflow sensor assembly of claim 23, wherein the pressure sensor is fluidly coupled to the first tube and the second tube.

25. The airflow sensor assembly of claim 23, further comprising a gasket protection ring configured to fit over an outer surface of the gasket.

26. The airflow sensor assembly of claim 21, further comprising a damper control assembly communicatively coupled to the pressure sensor.

27. The airflow sensor assembly of claim 26, wherein the damper control assembly comprises an air damper assembly, a motor, and an actuator.

28. The airflow sensor assembly of claim 21, wherein each aperture of the first plurality of apertures is orthogonal to a direction of airflow through the air duct.

29. The airflow sensor assembly of claim 21, wherein said hollow ring has an outer diameter in the range of 0.5 inches to 0.75 inches.

30. An airflow sensor assembly for an air duct having an inner wall and an outer wall;

the airflow sensor assembly includes:

a high voltage detection device;

a low pressure detection device, the low pressure detection device comprising:

an air flow restrictor; and

a first plurality of apertures defined in the low pressure detection device and spaced around a perimeter of the air duct;

a first gasket having a recessed area defined therein and a first connection opening, the first gasket being mounted on the outer wall and proximate the first plurality of apertures and the airflow restrictor; and

A first tube fluidly coupled to the first connection opening; and

31. The airflow sensor assembly of claim 30, wherein the airflow restrictor comprises a shroud component coupled with an inner wall of the air duct.

32. The airflow sensor assembly of claim 30, wherein the airflow restrictor comprises a channel disposed in an inner wall of the air duct.

33. The airflow sensor assembly of claim 30, wherein said high pressure sensing means comprises:

a second plurality of apertures defined in the high pressure detection device and spaced around a perimeter of the air duct;

a second gasket having a recessed area defined therein and a second connection opening, the second gasket fitting over the outer wall and adjacent the second plurality of apertures; and

a second tube fluidly coupled to the second connection opening.

34. The airflow sensor assembly of claim 33, wherein the pressure sensor is fluidly coupled to the first tube and the second tube.

35. The airflow sensor assembly of claim 30, further comprising a plurality of washer protection rings configured to fit over at least one of an outer surface of the first washer or an outer surface of the second washer.

36. The airflow sensor assembly of claim 30, further comprising a damper control assembly communicatively coupled to the pressure sensor.

37. The airflow sensor assembly of claim 36, wherein the damper control assembly comprises an air damper assembly, a motor, and an actuator.

38. A method of sensing airflow in an air duct, the method comprising:

a high pressure measurement is received from a high pressure detection device,

receiving a low pressure measurement from a low pressure detection device, the low pressure detection apparatus comprising:

a hollow ring disposed within an inner wall of the air duct, the hollow ring having an inner peripheral portion and an outer peripheral portion; and

a first plurality of apertures defined in the low pressure detection device and spaced about an inner peripheral portion of the hollow ring;

A first tube fluidly coupled to the first connection opening; and

an air velocity through the air duct is calculated based on the high air pressure measurement and the low air pressure measurement.

39. The method of claim 38, wherein the high voltage detection device comprises:

a gasket having a recessed area defined therein and a second connection opening, the gasket fitting over an outer wall of the air duct and adjacent to the second plurality of apertures; and

a second tube fluidly coupled to the second connection opening.

40. The method of claim 38, wherein each aperture of the first plurality of apertures is orthogonal to a direction of airflow through the air duct.

41. An airflow sensor assembly for an air duct, the air duct having an interior; the airflow sensor assembly includes:

a high-voltage detection member;

a low pressure detection member, the low pressure detection member comprising:

a surface disposed inside the air duct and configured to provide air restriction inside the air duct, the surface having a plurality of first apertures spaced apart in the interior; and

A pressure sensor system configured to be fluidly coupled to the high pressure sensing member and the low pressure sensing member.

42. The airflow sensor assembly for an air duct of claim 41, wherein the surface is a recessed portion of a wall of the air duct, and the pressure sensor system includes a first sensor coupled to the high pressure member and a second sensor coupled to the low pressure member.

43. The airflow sensor assembly of claim 42 wherein said high pressure sensing member comprises:

a first gasket having a recessed area defined therein and a first connection opening, the first gasket fitting over the wall and adjacent to a second aperture in the wall of the air duct; and

a first tube fluidly coupled to the first connection opening.

44. The airflow sensor assembly of claim 42, wherein said low pressure sensing member comprises:

a first gasket having a first connection opening, the first gasket fitting on the wall and forming a chamber having the first bore; and

A first tube fluidly coupled to the first connection opening.

45. The airflow sensor assembly of claim 43, wherein said low pressure sensing member comprises:

a second gasket and a second connection opening, the second gasket fitting on the wall and forming a chamber with the first bore; and

a second tube fluidly coupled to the second connection opening, the second connection opening fluidly coupled to the chamber.

46. The airflow sensor assembly of claim 45, wherein the pressure sensor is fluidly coupled to the first tube and the second tube.

47. The airflow sensor assembly of claim 43, further comprising a gasket protection ring configured to fit over an outer surface of the first gasket.

48. The airflow sensor assembly of claim 41, wherein the surface is a portion of a wall of the air duct and the surface has a portion with a U-shaped cross-section that provides the air restriction, wherein the pressure sensor system includes a first sensor coupled to the high pressure member and the low pressure member.

49. The airflow sensor assembly of claim 48, wherein said first aperture is disposed in said portion at the bottom of said U-shaped cross-section.

50. The airflow sensor assembly of claim 41, wherein said surface is part of a wall of said air duct and said surface has portions forming channel features providing said air restriction, said channel features having a depth of from 0.5 inches to 0.75 inches.

51. An airflow sensor assembly for an air duct having an inner wall and an outer wall; the airflow sensor assembly includes:

a first pressure structure;

a second pressure structure, the second pressure structure comprising:

an airflow restricting surface; and

a plurality of first apertures defined in the second pressure structure and spaced about a periphery of the air duct;

a first gasket having a first connection opening, the first gasket being fitted on the outer wall and proximate the first aperture, and the first gasket and the airflow-restricting surface being configured to define a chamber; and

at least one pressure sensor configured to be fluidly coupled to the first pressure structure and the second pressure structure, or a first pressure sensor configured to be fluidly coupled to the first pressure structure and a second sensor configured to be fluidly coupled to the second pressure structure.

52. The airflow sensor assembly of claim 51, wherein said airflow restricting surface is formed by a U-shaped recess in said outer wall.

53. The airflow sensor assembly of claim 51, wherein said second pressure structure comprises:

a second aperture defined in the outer wall;

a second tube fluidly coupled to the second connection opening.

54. The airflow sensor assembly of claim 53, wherein said pressure sensor is fluidly coupled to a first tube fluidly coupled to said chamber and said second tube.

55. The airflow sensor assembly of claim 54, further comprising a plurality of washer protection rings configured to fit over at least one of an outer surface of the first washer or an outer surface of the second washer.

56. The airflow sensor assembly of claim 51, further comprising a damper control assembly communicatively coupled to said pressure sensor.

57. The airflow sensor assembly of claim 56, wherein said damper control assembly comprises an air damper assembly, a motor, and an actuator.

58. A method of sensing airflow in an air duct, the method comprising: :

receiving a first barometric pressure measurement from a first pressure sensing structure;

receiving a second barometric pressure measurement from a second pressure sensing structure, the second pressure sensing structure comprising:

a restriction portion disposed within an inner wall of the air duct, the restriction portion having a first aperture defined therein; and

a first tube fluidly coupled to a first connection opening in communication with a chamber at least partially defined by the restriction; and

an air velocity through the air duct is calculated based on the first air pressure measurement and the second air pressure measurement.

59. The method of claim 58, wherein the first pressure detection structure comprises:

a gasket having a recessed area defined therein and a second connection opening, the gasket fitting over an outer wall of the air duct and adjacent to a second aperture in the air duct; and

A second tube fluidly coupled to the second connection opening.

60. The method of claim 58, wherein each of the apertures is orthogonal to a direction of airflow through the air duct.