US20140134009A1

US20140134009A1 - Tunable vibration and acoustic noise suppression in an air-mover assembly

Info

Publication number: US20140134009A1
Application number: US13/677,969
Authority: US
Inventors: Raymond Wojcieson
Original assignee: Lennox Industries Inc
Current assignee: Lennox Industries Inc
Priority date: 2012-11-15
Filing date: 2012-11-15
Publication date: 2014-05-15

Abstract

A mounting assembly comprising a rigid connector structure configured to attach an air-regulating plate of an air-mover unit to an enclosure of the air-mover unit, wherein the air-regulating plate is in an air-flow pathway of air-moving elements of the air-mover unit. The assembly also comprises a flexible connector structure, wherein at least part of the flexible connector structure is held in-between a plate-mounting portion of the air-regulating plate and an enclosure-mounting portion of the enclosure by the rigid connector structure.

Description

TECHNICAL FIELD

This application is directed, in general, to mounting assemblies and, more specifically, to assemblies for mounting motors.

BACKGROUND

Air mover devices in space-conditioning systems can generate significant amounts acoustic noise, in particular, pure tone acoustic noise, which is objectionable to the end-users of the space-conditioning system. One conventional belief has been that such acoustic noise results from pressure waves generated by unsteady flow caused by the air mover, forcing the air through the air-mover at discrete frequencies with the air going from a compressed to less compressed state as it leaves the air mover.

SUMMARY

One embodiment of the present disclosure is a mounting assembly. The assembly comprises a rigid connector structure configured to attach an air-regulating plate of an air-mover unit to an enclosure of the air-mover unit, wherein the air-regulating plate is in an air-flow pathway of air-moving elements of the air-mover unit. The assembly also comprises a flexible connector structure, wherein at least part of the flexible connector structure is held in-between a plate-mounting portion of the air-regulating plate and an enclosure-mounting portion of the enclosure by the rigid connector structure.
Another embodiment of the present disclosure is an air-mover unit for a space-conditioning system. The unit comprises an enclosure configured to hold air-moving elements there-in and an air-regulating plate situated over an air-exit opening of the enclosure and in an air-flow pathway of the air-moving elements. The unit also comprises one or more mounting assemblies. Each one of the mounting assemblies includes a rigid connector structure configured to attach the air-regulating plate to the enclosure, and, a flexible connector structure, wherein at least part of the flexible connector structure is held by the rigid connector structure, in-between a mounting portion of the air-regulating plate and a mounting portion of the enclosure.
Another embodiment of the present disclosure is a method of assembling an air-mover unit. The method comprises placing air-moving elements of the air-mover unit inside of an enclosure of the air-mover unit. The method also comprises situating an air-regulating plate over an air-flow opening of the enclosure and in an air-flow pathway of the air-moving elements. The method further comprises attaching the air-regulating plate to the enclosure using a mounting assembly. Attaching the air-regulating plate including fixing a plate-mounting portion of the air-regulating plate and an enclosure-mounting portion of the enclosure in-between one end and an opposite end of a rigid connector structure of the mounting assembly, wherein at least part of a flexible connector structure of the mounting assembly is in-between the plate-mounting portion and the enclosure-mounting portion.

BRIEF DESCRIPTION

Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

FIG. 1A illustrates exploded isometric detailed view of an example motor mounting assembly of the disclosure;

FIG. 1B illustrates exploded isometric detailed view of another example motor mounting assembly of the disclosure;

FIG. 1C illustrates exploded isometric detailed view of another example motor mounting assembly of the disclosure;

FIG. 2 illustrates exploded isometric view of an example air-moving unit that comprises an embodiment of mounting assembly of the disclosure, such as any of the embodiments discussed in the context of FIGS. 1A-1C; and

FIG. 3 presents a flow diagram of an example method 300 of assembling an air-mover unit, such as any of the units 102 discussed in the context of FIGS. 1A-2.

DETAILED DESCRIPTION

The term, “or,” as used herein, refers to a non-exclusive or, unless otherwise indicated. Also, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments.
The embodiments of the present disclosure benefit from an examination of a new hypothesis on how acoustic noise may be generated in air mover devices. As part of the present disclosure it was hypothesized that substantial amount of the acoustic noise, especially the most objectionable pure tone noise, is a result of pressure changes associated with the moving elements of the air mover releasing energy into the moving components and housing components of the air mover at discrete frequencies. The released energy causes these components to vibrate. In the case of the moving components, much of the energy is thought to be suppressed and absorbed because of high mass and mounting configuration of the moving components. In the case of the housing components, due to their lower mass and present configuration, more of the released energy gets translated into vibration energy, which in turn, leads to the acoustic noise, including the pure tone noise.
Based upon the new hypothesis, it was thought that acoustic noise suppression could be achieved by diverting at least some of the released energy into flexible connectors as part of embodiments of a mounting assembly used to hold certain components of the housing together. In particular, the use of flexible connectors as part of a mounting assembly holding a blower housing cutoff plate to other parts of the housing was discovered to be effective at suppressing acoustic noise, including pure tone noise.
One embodiment of the present disclosure is a mounting assembly. FIGS. 1A-1C illustrate exploded isometric detail views of different example embodiments of a motor mounting assembly 100 of the disclosure, e.g., for an air-mover unit 102. For clarity, certain features of the assembly 100 may be depicted or discussed in the context of one of FIGS. 1A-1C. However, any of the features depicted or discussed in the context of one of FIGS. 1A-1C could be used or combined with any of the other embodiments of the mounting assembly discussed herein.
With continuing reference to FIGS. 1A-1C, the assembly 100 comprises a rigid connector structure 105 (having cylindrical shank 107) configured to attach an air-regulating plate 110 of the unit 102 to an enclosure 115 of the unit 102. The air-regulating plate 110 is in an air-flow pathway 120 of air-moving elements of the unit 102 (e.g., through an opening 122 of the enclosure 115). The assembly 100 also comprises a flexible connector structure 125. As illustrated, in some cases, the flexible connector structure 125 can have a cylindrical shape structure having a central long-axis opening 127 to accommodate the shank 107 of the rigid connector structure 105 there-through (e.g., along dimension 129). At least part 130 of the flexible connector structure 125 is held in-between a plate-mounting portion 135 of the air-regulating plate 110 and an enclosure-mounting portion 140 of the enclosure 115 by the rigid connector structure 105.
As illustrated, the plate-mounting portion 135 and enclosure-mounting portion 140 can be adjacent to or near the opening 122 in the enclosure 115 through which the air-flow pathway 120 is directed.
The rigid connector structure 105 has sufficient mechanical strength to hold the air regulating plate 115 and the enclosure 115 together during the operation of the air-mover unit 102. For instance, some embodiments of the rigid connector structure 105 can be made of plastic, metal (e.g., steel or aluminum) or other similar materials.
As illustrated in FIGS. 1A-1C, in some embodiments, the rigid connector structure 105 is shaped as a pin that has a cylindrical shank 107 wherein the shank 107 is shaped to hold the air-regulating plate 110 to the enclosure 115 by passing through an opening 144 of the plate-mounting portion 135 of the air-regulating plate 110 and through an opening 146 of the enclosure-mounting portion 140 of the enclosure 115.
As also shown in FIGS. 1A-1C, in some cases, to accommodate embodiments of a pin-shaped rigid connector structure 105 there-through at a substantially perpendicular angle, the mounting portion 135 of the air-regulating plate 110, or, the mounting portions 140 of the enclosure 115 can be a bent or a raised portions of the plate 110 or the enclosure 115, respectively. For instance, the mounting portion 135 can be bent to form a plane 150 that is substantially perpendicular to a major plane 152 of the plate 110. For instance, a planar portion 154 of the enclosure 115 can be stamped, punched or pressed to form the enclosure-mounting portions 140 which is raised above of a major plane 155 of the enclosure 115.
In some cases, as illustrated in FIG. 1A-1C, one end 156 (e.g., a retaining end) of the pin-shaped rigid connector structure 105 has a flat head that is too large to pass through the opening 144 of the plate-mounting portion 135 or the opening 146 of the enclosure-mounting portion 140 and thereby retains the one end 156 to the outside of the opening 144. In some cases, the flat head of the retaining end 156 can have a slot therein or have hexagonal- or rectangular shape to use a mounting tool such as a screw driver or wrench to facilitate passing the other end 157 of the pin-shaped rigid connector structure 105 through the openings 144, 146 and/or secure the other end 157 to the enclosure-mounting portion. In some cases, as illustrated in FIG. 1A, the pin-shaped rigid connector structure 105 is shaped as a screw with a threaded ridge 158 along the cylindrical shank 107. In some such cases, the other end 157 of the connector structure 105 can form an apex to facilitate boring through the opening 146 of the plate-mounting portion 135.
As further non-limiting examples, in some embodiments as illustrated in FIG. 1B, the rigid connector structure 105 can be a bolt with a threaded shank 107 and further include a nut 160 configured to be treaded on to the other end 157. In other cases, as illustrated in FIG. 1C, the rigid connector structure 105 can be a bolt with a smooth shank 107 designed to fit through pre-formed openings 144, 146 and the other end 157 has an opening 158 to accommodate a hitch pin 162 there-through to prevent the bolt from sliding out of the openings 144, 146. In still other cases, the rigid connector structure 105 can be a rivet with a smooth shank 107 that fits through the openings 144, 146, and the other end 157 is buckled or deformed to be larger than the openings 144, 146. In still other cases, the rigid connector structure 105 can be a clamp that clamps around the plate-mounting portion 135 and the enclosure-mounting portion 140. Based upon the present disclosure, one skilled in the art would appreciate that other embodiments of the rigid connector structure 105 could be used to hold the air regulating plate 110 and the enclosure 115 together with the flexible connector structure 125 held there-between.
In some embodiments, such as illustrated in FIGS. 1A and 1C, the flexible connector structure 125 includes, or is, a rubber grommet having an axial opening 127 that surrounds at least part of the cylindrical shank 107 of the rigid connector structure 105 and is thereby held in place by the rigid connector structure 105. It is desirable for the rubber grommet to be composed of a soft elastomeric material rubber material that is compressible so as to absorb the vibrational energy transmitted to the flexible connector structure 125 and thereby suppress acoustic noise. For instance, in some cases the flexible connector structure 125 is a rubber grommet composed of an elastomer having a durometer hardness in the range of 30 Shore A to 40 Shore A. For instance, in some cases, elastomer is an ethylene propylene diene monomer rubber. Based on the present disclosure one skilled in the art would appreciate other types of materials that would be appropriate to use.
In other embodiments, as illustrated in FIG. 1B, the flexible connector structure 125 includes, or is, a spring. For instance, the flexible connector structure 125 can be a cylindrically-shaped spring having the axial opening 127 that fits around the cylindrical shank 107 of the rigid connector structure 105, thereby keeping the spring held in place by the rigid connector structure 105.
In some embodiments as shown in FIG. 1A, the entire flexible connector structure 125 (e.g., configured as either a rubber grommet or a spring) can be located in-between the plate-mounting portion 135 and the enclosure-mounting portion 140. In some cases as shown in FIG. 1C, another portion 164 (e.g., continuous with the rest of the flexible connector structure 125) of the flexible connector structure 125 is located in-between the enclosure-mounting portion 140 and the end 156 of the rigid connector structure 105 that is distal to the air-regulating plate 110. Such a configuration helps to keep the flexible connector structure 125 in its proper place during the assembly of the mounting assembly 100. Additionally, the portion of the flexible connector structure 125 in-between the enclosure-mounting portion 140 and the rigid connector structure end 156 can further absorb vibrational energy and thereby enhance acoustic noise suppression of the assembly 100.
As an example, the flexible connector structure 125, when configured as a cylindrically shaped rubber grommet, can have a central annular slot that separates the flexible connector structure 125 into a portion 130 that is located in-between the plate-mounting portion 135 and the enclosure-mounting portion 140, and, another portion 164 that is located in-between the enclosure-mounting portion 140 rigid connector structure end 156. Because the flexible connector structure 125 configured as a rubber grommet is soft and compressible, one of the portion 130 or other portion 164 can be squeezed through the enclosure opening 146, e.g., in the factory, and thereby hold the rubber grommet in place adjacent to the enclosure-mounting portion 140 without further action on the part of the installer.
In still other embodiments, such as when as illustrated in FIG. 1B the entire flexible connector structure 125 is located in-between the plate-mounting portion 135 and the enclosure-mounting portion 140, the assembly 100 can further include another flexible connector structure 165 located in-between the enclosure-mounting portion 140 and the end 156 of the rigid connector structure 105 that is distal to the air-regulating plate 110. The second flexible connector structure 165 (e.g., configured as a cylindrically-shaped rubber grommet or a spring) can further absorb vibrational energy and thereby enhance acoustic noise suppression of the assembly 100.
As further illustrated in FIG. 1A some embodiments of the assembly 100 can further include a rigid sleeve 170 having a cylindrical shank 176 with an axial opening 174 allowing a cylindrical shank 107 of the rigid connector structure 105 there-through. The cylindrical shank 176 of the rigid sleeve 170 passes through an axial opening 127 of the flexible connector structure 125 and the opening 144 of the plate-mounting portion 135.
The rigid sleeve 170 can be composed of a material (e.g., aluminum, steel or hard plastic) having sufficient durability to withstand forces applied to it without failure and with properties which will suppress vibrations at frequencies different than those that the grommet 125 are most effective in suppressing, thus providing a wider range of vibration suppression capabilities
In some cases, the rigid sleeve 170 helps prevent shipping damage and long-term changes in shape of the flexible connector structure 125. For instance, flexible connector structure 125, configured as a rubber grommet, can be subject to creep or tearing from rubbing against any of the rigid connector structure 105, plate-mounting portion 135 or enclosure-mounting portion 140. Such damage to the flexible connector structure 125 can cause the mounting assembly 100 to fail to suppress acoustic noise, or, reduce the efficiency of the air-mover unit 102, e.g., due to misalignment of the air-regulating plate 110 relative to the enclosure opening 122.
As further illustrated in FIG. 1A, to further protect the flexible connector structure 125, the rigid sleeve 170 can further include an end-flange 177 having an outer diameter 178 that is larger than a diameter 180 of the axial opening 174 of the enclosure-mounting portion 140 and the opening 127 of the flexible connector structure 125, wherein one end 182 of the flexible connector structure 125 rests against the end-flange 176.
In some embodiments, to provide fine-tuning of acoustic noise suppression, the rigid sleeve 170 provides compression control of the flexible connector structure 125, when the flexible connector structure 125 is held between the plate-mounting portion 135 and the enclosure-mounting portion 140.
For instance, in some cases, the cylindrical shank 176 of the rigid sleeve 170 stops around the part of structure that defines the opening 144 of the plate mounting portion 135 to thereby stop full compression of the flexible connector structure 125. As an example, the total length 184 of the shank 176 can be adjusted to prevent full compression of the flexible connector structure 125, e.g., from over-tighten of the rigid connector structure 105 to the plate-mounting portion 135 and/or enclosure-mounting portion 140. Fully compressing the flexible connector structure 125 could detrimentally prevent the structure's 125 ability to absorb energy from the air-mover unit 102, and thereby detract from efficient acoustic noise suppression.
For instance, the outer diameter 179 or length 184 of the shank 176 can be adjusted to permit a specific degree of compression of the flexible connector structure 125 (e.g., in a range from about 10 to 90 percent compression as compared to a fully relaxed state with no compressive load), to thereby fine-tune the suppression of particular frequencies, e.g., pure-tone frequencies, of acoustic noise generated by the air-mover unit 102.
Embodiments of the mounting assembly can include different types of rigid and flexible connector structures located to hold in different portions of the air-regulating plate to different places of the enclosure. For example, as illustrated in FIG. 1C, other embodiments of the mounting assembly 100 can further include a secondary rigid connector structure 190 configured to attach the air-regulating plate 110 to the enclosure 115 and a secondary flexible connector structure 192. At least part of the secondary flexible connector structure 192 is held in-between a secondary plate-mounting portion 194 of the air-regulating plate 110 and a secondary enclosure-mounting portion 196 of the enclosure 115 by the rigid connector structure 190. The secondary plate-mounting portion 194 is in a different location (e.g., a rear portion of the plate) than the plate-mounting portion 135 and the secondary enclosure-mounting portion 196 is in a different location (e.g., distal to the air-flow pathway opening 122) than the enclosure-mounting portion 140.
In some cases, the secondary flexible connector structure 192 can be of the same type, size and material composition as the primary flexible connector structure 125. In other cases one or both of the type, size or composition of the secondary flexible connector structure 192 than the primary flexible connector structure 125, e.g., to enhance acoustic noise suppression or mechanical stability increasing greater creep and tear resistance.
For instance, in some embodiments, the primary flexible connector structure 125 can be or include a spring, and, the secondary flexible connector structure 192 can be or include a rubber grommet. Or, in some embodiments as shown in FIG. 1C, both of the primary and secondary flexible connector structures 125, 190 can be or include a rubber grommet. However, the rubber grommet of the primary flexible connector structure 125 is composed of the elastomer having a durometer hardness scale in a range of 30 Shore A to 40 Shore A, and, the secondary flexible connector structure 192, is composed of a different elastomer having a durometer hardness scale in a range of 55 Shore A to 65 Shore A {e.g., Styrene Butadiene Rubber) to provide a flexible grommet with greater mechanical stability than the rubber grommet of the primary flexible connector structure 125.
For instance, in still other embodiments, both of the primary and secondary flexible connector structures 125, 190 can be or include a rubber grommet (or spring) composed of the same material. But the rubber grommet (or spring) of the primary and secondary flexible connector structures 125, 190 can different sizes to hold the different plate-mounting portions 135, 194 to differently shaped enclosure-mounting portions 140, 196, respectively.
Similarly, the primary rigid connector structure 110 and secondary rigid connector structure 190 can be of same type, size and material composition as the primary flexible connector structure 125, or, different type, size or material composition as needed to accommodate the configurations of the primary and secondary flexible connector structures 125, 190.
Another embodiment of the disclosure is an air mover unit for a space-conditioning system. For example, the space-conditioning system can be an HVAC or heat pump system used in commercial or residential buildings. FIG. 2 presents a perspective view of an example air-mover unit 102.
With continuing reference to FIGS. 1A-2 throughout, the example air-mover unit 102 depicted in FIG. 2 comprises an enclosure 115 configured to hold air-moving elements 205 there-in. The unit 102 also comprises an air-regulating plate 110 situated over an air-exit opening 122 of the enclosure and in an air-flow pathway 120 of the air-moving elements 205). The unit 102 further comprises one or more mounting assemblies 100. The mounting assembly 100 can be configured as any of the example mounting assemblies 100 discussed in the context of FIGS. 1A-1C. Referring to FIGS. 1A-1C, each of the mounting assemblies 100 includes a rigid connector structure 105 configured to attach the air-regulating plate 110 to the enclosure 110 and a flexible connector structure 125, wherein at least part of the flexible connector structure 125 is held, by the rigid connector structure 105, in-between a mounting portion 135 of the air-regulating plate 110 and a mounting portion 140 of the enclosure 115.
As illustrated in FIG. 2, in some cases, the air-moving elements 205 are blades of a wheel 210 of the air-mover unit 102 (e.g., an indoor blower unit 102 of an HVAC system 200) that is configured as a centrifugal blower, and in such cases, the enclosure 115 is a blower housing. As further illustrated the unit 102 can further include a motor 215 configured to drive the air-moving elements 205, e.g., by rotating the wheel 210. For instance, is some cases the motor 215 can be an Electronically Commutated Motor. Such motors, while efficient at generating air flow, can also generate pulsations that can lead to system vibrations. In other cases, the air-moving elements 205 can be blades of a propeller of the air-mover unit 102 configured as a fan blower (e.g., an outdoor fan unit 102 of an HVAC system 200).
The air-regulating plate 110, sometimes referred to as an air cut-off plate, can be composed of metal such as aluminum and shaped and as illustrated in FIG. 2, can have a curved shape to accommodate the shape of the moving elements 205 and wheel 210. However, the air-regulating plate 110 other shapes and materials could be used to focus the airflow pathway 120 and increase the air pressure generated by the air-mover unit 102 as needed by the space-conditioning system 200.
As illustrated in FIG. 2, in some cases, the air-regulating plate 110 is a physically separate structure from the enclosure 115 and is only connected to the enclosure 115 by the one or more mounting assemblies 100.
However, in other cases, the air-regulating plate 110 can be permanently fixed to or continuous with the enclosure 115, but still have a free-moving adjustable portion. Once the location of the adjustable portion is set, the one or more mounting assemblies 100 can hold the plate 110 to the enclosure 115 such that the flexible connector structure 125 can dissipate the energy transferred from the air-flow 120 to the plate 110.
Another embodiment of the present disclosure is a method of assembling an air-mover unit. FIG. 3 presents a flow diagram of an example method 300 of assembling an air-mover unit, such as any of the units 102 discussed in the context of FIGS. 1A-2.
With continuing reference to FIGS. 1A-2 throughout, as illustrated in FIG. 3, the method 300 comprises a step 305 of placing air-moving elements (e.g., blades 205 connected to wheel 210) of the air-mover unit 102 inside of an enclosure 115 of the air-mover unit 102. The method 300 also comprises a step 310 of situating an air-regulating plate 110 over an air-flow opening 122 of the enclosure and in an air-flow pathway 120 of the air-moving elements 205. The method 300 further includes a step 315 of attaching the air-regulating plate 110 to the enclosure 115 using a mounting assembly 100. The attaching step 315 includes a step 320 of fixing a plate-mounting portion 135 of the air-regulating plate 110 and an enclosure-mounting portion 140 of the enclosure 115 in-between one end 156 and an opposite end 157 of a rigid connector structure 105 of the mounting assembly 100 and a step 322 of placing at least part 130 of a flexible connector structure 125 of the mounting assembly in-between the plate-mounting portion 135 and the enclosure-mounting portion 140.
In some cases, as part of situating the plate in step 310 includes finding a position for the plate 110 that optimally focuses the airflow pathway 120 toward the opening 122 and increases the air pressure generated by the air-mover unit 102. Once the optimal position for the plate is located, the plate's 110 position is set in place by performing attaching step 315.
In some cases, attaching step 315 includes a step 324 of placing another portion 164 of the flexible connector structure 125 in-between the enclosure mounting portion 140 and the one end 156 (e.g., a retaining end) of the rigid connector structure 105 that is distal to the air-regulating plate 110. In other cases, in step 326, the entire flexible connector structure 125 is placed in-between the plate-mounting portion 135 and the enclosure-mounting portion 140. In still other cases, in step 328, another second flexible connector structure 165 (e.g., of different composition in some cases) is placed in-between the enclosure-mounting portion 140 and the one end 156 (e.g., retaining end) of the rigid connector structure 105 that is distal to the air-regulating plate 110.
In some cases, attaching step 315 includes a step 330 of passing the rigid connector structure 105 through an axial opening 174 of a cylindrical shank 176 of a rigid sleeve 170, and, a step 335 passing the cylindrical shank 176 of the rigid sleeve 170 through an axial opening 127 of the flexible connector structure 125. In some cases the cylindrical shank is sized to stop full compression of the flexible connector structure 125 when the air-regulating plate 110 is attached to the enclosure-mounting portion 115 in step 315.
In some cases, attaching step 315 can include a step 340 of adjusting a degree of compression of the part 130 of the flexible connector structure 125 located in-between the plate-mounting portion 135 and the enclosure-mounting portion 140 to minimize acoustic noise generated when the air-moving unit 102 moves air through the air-flow opening 122. For instance, part of step 340 can include adjusting the degree of compression to minimize acoustic noise generated when the air-moving unit 102 moves air through the air-flow opening 122. For instance, as part of step 340, in step 342 connection end (e.g., the other end 157) of the rigid connector structure 105 is connected to the plate-mounting portion 135, e.g., such that the opposite end (e.g., retainer end 156) of the rigid connector structure is adjacent to enclosure-mounting portion, and, in step 344, the connection end is mounted further into the plate-mounting portion 135 so that flexible connector structure 125 is compressed. For instance, the rigid connector structure 105, configured as a bolt, or screw, can be rotated around the structure's 105 long axial length (e.g., an axis along the length of the shank 107) so that the connection end is mounted further into the plate-mounting portion 135. In some cases, as discussed above, the rigid sleeve 170 can control the degree of compression of the part 130 of the flexible connector structure 125 when the tightening step 354 is applied.
Those skilled in the art to which this application relates will appreciate that other and further additions, deletions, substitutions and modifications may be made to the described embodiments.

Claims

What is claimed is:

1. A mounting assembly, comprising:

a rigid connector structure configured to attach an air-regulating plate of an air-mover unit to an enclosure of the air-mover unit, wherein the air-regulating plate is in an air-flow pathway of air-moving elements of the air-mover unit; and

a flexible connector structure, wherein at least part of the flexible connector structure is held in-between a plate-mounting portion of the air-regulating plate and an enclosure-mounting portion of the enclosure by the rigid connector structure.

2. The assembly of claim 1, wherein the rigid connector structure is shaped as a pin having a cylindrical shank wherein the shank is shaped to hold the air-regulating plate to the enclosure by passing through an opening of the plate mounting portion of the air-regulating plate and an opening of the enclosure mounting portion of the enclosure.

3. The assembly of claim 2, wherein the pin is shaped as a screw and there is an external threaded rigid along the cylindrical shank.

4. The assembly of claim 1, wherein the flexible connector structure includes a rubber grommet having an axial opening that surrounds part of a cylindrical shank of the rigid connector structure.

5. The assembly of claim 4, wherein the rubber grommet is composed of an elastomer having durometer hardness scale in a range of 30 Shore A to 40 Shore A.

6. The assembly of claim 1, wherein the flexible connector includes a cylindrical spring having an axial opening that fits around a cylindrical shank of the rigid connector structure.

7. The assembly of claim 1, wherein the entire flexible connector structure is located in-between the plate mounting portion and the enclosure mounting portion.

8. The assembly of claim 1, wherein a portion of the flexible connector structure is located in-between the enclosure mounting portion and an end of the rigid connector structure that is distal to the air-regulating plate.

9. The assembly of claim 1, further including another flexible connector structure located in-between the enclosure mounting portion and an end of the rigid connector structure that is distal to the air-regulating plate.

10. The assembly of claim 1, further including a rigid sleeve having a cylindrical shank with an axial opening allowing a cylindrical shank of the rigid connector structure there-through, wherein the cylindrical shank of the rigid sleeve passes through an axial opening of the flexible connector structure and the opening of the plate mounting portion.

11. The assembly of claim 10, wherein the rigid sleeve further includes an end-flange having a diameter that is larger than a diameter of the axial opening of the flexible connector structure, wherein one end of the flexible connector structure rests against the end-flange.

12. The assembly of claim 11, wherein the rigid sleeve provides compression control of the flexible connector structure when the flexible connector structure is held between the plate mounting portion and the enclosure mounting portion.

13. The assembly of claim 12, wherein the cylindrical shank of the rigid sleeve stops against the opening of the enclosure mounting portion to thereby prevent full compression of the flexible connector structure.

14. The assembly of claim 12, wherein an outer diameter or length of the cylindrical shank are adjusted to provide a specific degree compression of the flexible connector structure that suppresses a pure-tone frequency of acoustic noise generated by the air-mover unit.

15. An air-mover unit for a space-conditioning system, comprising:

an enclosure configured to hold air-moving elements there-in;

an air-regulating plate situated over an air-exit opening of the enclosure and in an air-flow pathway of the air-moving elements; and

one or more mounting assemblies, each of the mounting assemblies including:

a rigid connector structure configured to attach the air-regulating plate to the enclosure; and

a flexible connector structure, wherein at least part of the flexible connector structure is held, by the rigid connector structure, in-between a mounting portion of the air-regulating plate and a mounting portion of the enclosure.

16. The air-mover unit of claim 15, wherein the air-moving elements are blades of a wheel of the air-mover unit configured as a centrifugal blower.

17. The air-mover unit of claim 15, wherein the air-moving elements are blades of a propeller of the air-mover unit configured as a fan blower.

18. The air-mover unit of claim 15, wherein the air-regulating plate is a physically separate structure from the enclosure and is only connected to the enclosure by the one or more mounting assemblies.

19. A method of assembling an air-mover unit, comprising:

placing air-moving elements of the air-mover unit inside of an enclosure of the air-mover unit;

situating an air-regulating plate over an air-flow opening of the enclosure and in an air-flow pathway of the air-moving elements; and

attaching the air-regulating plate to the enclosure using a mounting assembly, including fixing a plate-mounting portion of the air-regulating plate and an enclosure-mounting portion of the enclosure in-between one end and an opposite end of a rigid connector structure of the mounting assembly, wherein at least part of a flexible connector structure of the mounting assembly is in-between the plate-mounting portion and the enclosure-mounting portion.

20. The method of claim 19, wherein attaching the air-regulating plate to the enclosure includes adjusting a degree of compression of the part of the flexible connector structure located in-between the plate-mounting portion and the enclosure-mounting portion to minimize acoustic noise generated when the air-moving unit moves air through the air-flow opening.