SI21775A - Fan-motor assembly with noise dampening - Google Patents

Abstract

The low-noise fan-motor assembly for moving air includes a motor assembly, featuring a rotating shaft and a fan assembly, which is linked to the rotating shaft generating an air current and is travelling at least along a part of the motor assembly. The channel, which is selfextinguishable, flame-retardand and noise-dampening, is installed in such a way that it encloses the motor assembly. In the ideal case the material which the channel is made of, is a V-O class foam. The fan assembly includes a fan, which is attached to the shaft and a diffusion element/bracket, linked to the motor assembly which accepts the rotating shaft. The fan enclosure is attached to the diffusion element/bracket, where the fan rotation provides the suction of air through the fan enclosure and out of the diffusion element/bracket assembly, where the diffusion element/bracket assembly features at least one attached foam part, linked to the curved blades to reduce the noise level of air travelling through it.

Description

Silencer fan-motor assembly

The present invention mainly relates to electric motors or generators, more specifically to a motor-fan unit where a heat-stable sound-absorbing foam is used which is located near moving parts or surrounds moving parts to absorb noise produced by the unit.

BACKGROUND OF THE INVENTION

Electric motors and generators are well known in the art and are used for various purposes. They are also used for air management. In this case, the electric motor is coupled to a fan to generate airflow or vacuum, depending on the purpose. Often a fan is used to provide cooling air to the engine. In such cases, the fan mounted on the shaft driven by the engine draws air into the fan housing where the air is compressed. The compressed air is then discharged into the engine housing through one or more openings that direct air through the motor windings to remove heat and blow it out of the engine housing. It is also possible that the fan housing has outlets so that the air flow bypasses the windings of the motor. Known engine assemblies tend to make noise. The fan contains a windmill that usually has sharp edges. Noise is generated as air flows and flows over these edges and forward toward other guiding surfaces. Apart from noise being an undesirable property, it causes inefficiency of the air flow, which impairs engine performance.

While the use of foam to suppress noise caused by various devices, including motors, is known, the foam is always positioned at a certain distance from the heat-generating elements, thereby avoiding thermal decomposition of the foam. This makes foam positioning problematic and may require the construction of additional support structures inside the device. The use of foam to dampen the noise in engines is also problematic because once the foam ignites, it burns, resulting in engine and related equipment malfunctioning. In order to ensure that the engine temperature does not reach the foam temperature, expensive flow and / or temperature meters must be added to the assembly. When the sensor detects temperature or current, the engine shuts off to prevent foam from igniting. It follows that there is a need in the art for motor-fan assemblies that do not have these disadvantages.

BRIEF DESCRIPTION OF THE INVENTION

The present invention provides a low-noise air-to-air motor-fan unit comprising a rotary shaft motor assembly; the fan assembly coupled to said rotary shaft to rotate the fan and produce airflow that flows through at least a portion of the engine assembly; and a noise attenuation duct, which is located at least in part around said engine assembly.

The second object of the present invention is to provide a motor fan unit comprising a rotary shaft motor assembly; and the fan assembly coupled to the engine assembly, wherein the fan assembly comprises a fan mounted on a shaft, a shaft-mounted bracket where a fan carrying an engine assembly, wherein a bracket-mounted bracket, where the fan is through openings and a diffuser connected to a bracket, the part of the shaft where there is a fan, where the diffuser has peripheral through openings, where the rotation of the fan creates an air stream that flows through the openings in the carrier and through the peripheral openings, where the fan assembly carries at least one part of the foam to absorb the noise generated by the fan.

Short description of the pictures

For a complete understanding of the objects, techniques and structures of the present invention, we hereinafter refer to the accompanying drawings showing:

Figure 1: Floor plan in partial cross-section of the engine-fan unit according to the present invention, showing details of the composition;

Figure 2: Shows the back panel according to the invention and shows the details of the diffuser side of the bracket on the fan side;

Figure 3: Shows a spatial view of a radial diffuser according to the present invention;

Figure 4: Shows a spatial view *** of a diffuser according to the present invention;

Figure 5: Shows a peripheral bypass motor fan unit according to the present invention;

Figure 6: Displays a tangential bypass motor-fan unit according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows the motor-fan unit, numbered 10, which mainly comprises the engine assembly 15 and the fan assembly 25. The engine assembly comprises an electric motor 16 with armature or winding 17, a commutator 18, and brushes (not shown) providing connection the power source with commutator 18 and the windings 17. The shaft 20 is supported by suitable bearings so that it rotates freely and is connected to the commutator 18 to rotate with it.

As shown in Figure 1, the assembly of the motor assembled with commutator 18 is closer to the fan assembly

25. Fan assembly 25 of the motor-fan unit 10 comprises a fan 26 that is coupled to one end 27 of the shaft 20, for example by means of a nut that rotates together. The fan assembly 25 further comprises a housing 30 surrounding the fan 26. As is known in the art, the housing 30 has an axial opening through which the fan 26 draws air from the outside. In the embodiment shown, the housing 30 has a centrally located inlet opening 31 formed in the cover portion 32 of the frame and coaxially arranged with the axis A of the shaft 20. The fan 26 blows air and the blown air receives a diffuser 80 (described in more detail below), which distributes air, according to end-use needs. A more detailed description of the motor-fan unit 10 components can be found in U.S. Pat. No. 6,703,754 to which reference is made in the present application, and the present application focuses on the advantages of certain elements of the motor fan 10 unit.

In Figures 1 and 2, the assembly of the motor 15 is provided with a bracket on the fan side or a bracket assembly marked 35. The bracket on the fan side 35 generally comprises a portion of a flat plate 36 which may be circular as shown and the openings of the bracket 75 in the vicinity of the engine mounting parts 37 extending from the panel area towards the engine 16. The engine mounting parts 37 are adapted to support the assembly of the engine 15 and are adapted to reduce the noise generated by the engine fan unit 10 by using foam F on its inner surface, close to said openings of the carrier 75.

Foam 75 reduces vibrational noise by absorbing the waves generated by the movement of the fan winds through the air and by facilitating the movement of the resulting air flow from one direction to another. In other words, when the air is driven by the fan winds, the area of the plate 36 directs it through the openings 75 and towards the sections of the carrier 37. The foam F, which is glued or otherwise attached to the compartments 37, absorbs the noise generated by the air flow and prevents further flow. noise generation by means of an absorption surface for air flow.

Foam F is preferably a class V-0 foam. The characteristics of such foam are those defined by UL 94. The foam is high temperature resistant and is self-extinguishing in the event of fire, which means that if the foam receives enough heat to ignite, the resulting flame will not expand with further burning the foam when the heat source ceases. Such foam has a flashpoint of more than 400 ° C and a self-ignition temperature of at least 580 ° C. Preferably, this is melamine foam, and particularly advantageous is the use of Polydamp® foam (PMF; Polymer Technologies Inc.). PMF has extreme resistance to high temperatures and low flammability. When the ignition does not drip and stop burning as soon as the ignition source (heat) ceases. In addition, PMF produces very little fire and smoke. In fact, we have found that using such foam no longer requires the installation of expensive temperature or current sensors to maintain the engine at a specific temperature where the foam would otherwise ignite. In the engine fan unit 10 of the present invention, it is also advantageous to use a noise cancellation channel 200, which is at least partially, preferably fully, arranged around at least a portion of said engine assembly 15, as shown in Figure 1. This channel 200 is manufactured of VO grade foam, preferably of melamine foam. Channel 200 surrounds most of the engine 16 and absorbs and attenuates the noise generated by the engine assembly 15 and the fan assembly 25. Indeed, it is believed that the cellular structure helps to dissipate the noise frequencies generated by the fan assembly and the engine assembly and that the foam deflects the noise frequencies at labyrinthine mode so that, at the moment when the airflow leaves the engine assembly, the noise frequencies are significantly reduced.

The channel 200 is fixed to the fan assembly 25 on the side at the housing 204 of the channel 200, and the channel cover 202 covers the noise cancellation channel 200 at the more distant end 206, opposite the side at the housing 204. The channel cover 202 may have an upper opening 208 and in the embodiment shown , the engine portion may extend through the opening 208. If desired, the channel 200 may be longer than the engine length, as shown in the figure.

1. The channel may be secured by fasteners, clips, adhesive, may be secured by means of a socket joint or by any other means to secure the position of the channel near unit 10. The distal end 206 may be curved inward to form the opening of the channel 210; in this case, however, the use of cover 202 is not required. It should be emphasized that the use of cover 202 is optional. Class V-0 ensures that the foam F will not be damaged by heat released during engine operation 16. Preferably, the channel diameter 200 is no larger than the outer diameter of the housing 30, as shown, and it is also desirable that the duct cover 202 or channel opening 210 near or in contact with the engine assembly 15. We have found that Class V-0 foam can be placed in contact with or in close proximity to the engine assembly, as shown in the example of the channel 200 ', which provides the best noise reduction while the unit can operate normally.

This foam channel concept can also be used in the flow elements of the motor-fan units and in the tangential bypasses of the motor-fan units. Figure 5 shows a by-pass motor-fan unit 300 having a housing assembly 302 of the fan assembly 303 covered by a damping duct 304 made of class V-0 foam. The duct cover 306 is open at 308 and the duct cover preferably rests on the housing 302 as shown in 310. The housing 302 has a plurality of peripheral exhaust openings 311 for the outlet of airflow generated by the fan in the fan assembly 303. As said above, any conventional means are used to secure the channel to the unit. The side wall 312 of the channel 304 is preferably spaced from the housing 302, although it could also be touched.

In Fig. 6, the tangential bypass of the motor-fan unit 400 has a tangential exhaust port 402 extending from the fan assembly 403, which is covered by a noise-suppressing duct 404 made of V-0 foam. Duct 403 does not have a duct lid but is open at end 406. The side wall 408 preferably rests on the outer surface of the exhaust opening 410. It can extend from the inner surface of the duct in the form of internal flanges 408 forming a labyrinth path 410. Route 410 diverts airflow and flanges. effectively attenuate the noise generated by unit 400.

Additional advantages can be achieved by using V-0 foam on other elements of the fan-motor unit 10, especially on the diffuser-forming elements as disclosed below, by calling Figures 3 and 4. The diffuser 80 interacts with the bracket on the fan side 35 and distributes the air flow formed by the fan 26, which is called the diffuser / carrier assembly. The diffuser / carrier assembly (80/35) is coupled to the engine assembly 15 and receives a rotating shaft 20. The radial type diffuser assembly is shown in Figure 3 and is numbered 80A, and the hollow diffuser assembly is shown in Figure 4 and is indicated with the number 80B and both assemblies interact with the carrier on the fan side 35, where the fan 26 sucks air through the fan housing 30 and forcibly blows it out of the diffuser / carrier assembly. Air from the fan assembly 25 is distributed with these diffuser assemblies 80A, 80B. In the following, we will call the diffuser, irrespective of the design (radial or hollow), a "diffuser" and denote by number 80. The individual components of these diffusers, however, will contain an extension A or B.

The radial diffuser 80A (Figure 3) comprises a flat base portion 81, which may be annular to define the orifice 82. A plurality of peripheral blades 86A surrounds fan 26A and serves to guide the air outward from the side where the fan 85 is, where the part can be turned outward from the housing 30 through the plurality of openings 34 defined in the housing 30 (Figure 1). A second set of blades 87A, formed on the side of the motor 84 of the radial diffuser 80A, channels the rest of the air radially inward toward the center of the diffuser 80A. The blades 87A can be shaped into any pattern as required for a particular use, including a helical pattern and a windmill shape as shown. In contrast to the radial diffuser 80A, the hollow diffuser 80B, as shown in Figure 4, has peripheral blades 86B on the fan side 105 and closed channels 87B extending from the flat part 104 and arranged in similar patterns to the blades 86A, 87A of the radial type diffuser 80A to channel all inlet and outlet air as described above. The hollow diffuser housing 80B is completely closed.

The diffuser 80, hollow or radial type assemblies have a pair of slide brush assemblies 95 that touch the brush holders 120 (Figure 2). In the embodiment shown, ducts 93 are formed in the diffusers 80A and 80B between the pairs of individual brush portions 96, 97 on the motor side (84 for diffuser 80A and page 105 for diffuser 80B). Parts 96, 97 are positioned adjacent to the central aperture 82 and may extend radially into the aperture 82 for a certain distance. The hollow diffuser brush assemblies 95 differ in that they are surrounded by channels 87B as opposed to blades 87A. The present invention provides for the use of Class V-0 Foam F on certain diffuser elements. Specifically, V-0 foam is provided on surfaces that are affected by airflow during operation of the motor fan unit 10. More specifically, foam F is provided on blades 87A (radial diffuser) or closed ducts (hollow diffuser). It is understood that these helical patterns and windmill patterns effectively divert air flow and are therefore major factors in the generation of noise in the motor-fan unit 10, where they are used selectively. It is apparent, therefore, that the surfaces of the blades 87A and the closed channels 87B, which are twisted in the direction of rotation of the composition of the diffuser 80, are surfaces covered by foam F.

It is to be understood that a new and useful motor-fan assembly is disclosed in accordance with patent laws. Furthermore, it is also understood that various modifications are possible in the present invention, which do not depart from the spirit of the present invention. The claimed scope of the present invention is described in the appended claims.

Claims (23)

PATENT APPLICATIONS 1. Low-noise air displacement engine composition, characterized in that it contains: composition of rotary shaft motor; a fan assembly coupled to said rotary shaft that generates air flow through at least a portion of said engine assembly and a self-extinguishing and fireproof duct that dampens noise and at least partially encloses said engine assembly. Composition according to Claim 1, characterized in that the fan assembly has an outside diameter and said noise attenuation channel has a diameter of the channel that encloses the outer diameter of said fan. Composition according to claim 1, characterized in that said noise suppression channel is of foam material having self-extinguishing properties. Composition according to claim 1, characterized in that it further comprises: a duct cover attached to said noise-suppressing channel, said noise-suppressing channel having a housing end attached to said fan assembly opposite the distal end forming a duct opening and a duct cover affixed to said distal end. Assembly according to claim 4, characterized in that said channel has a through hole cover and wherein said engine assembly extends through said cover hole. Assembly according to claim 1, characterized in that said channel is in contact with said engine assembly. Assembly according to claim 1, characterized in that said noise-suppressing duct has a housing end attached to said fan assembly opposite the distal end. The assembly of claim 7, characterized in that the distal end is curved inwards to form the channel opening. Assembly according to claim 8, characterized in that said engine assembly extends through said channel opening and wherein the distal end is in contact with said engine assembly a. Composition according to claim 1, characterized in that said engine composition comprises: a fan attached to said shaft; a diffuser / carrier assembly coupled to said engine assembly, wherein said diffuser / carrier assembly receives said rotary shaft; a fan housing affixed to said diffuser / carrier assembly, wherein rotation of said fan draws air through said housing and out of said diffuser / carrier assembly, wherein said diffuser / carrier assembly has at least one foam part connected to said composition for reduction noise of air passing through; Composition according to claim 10, characterized in that said diffuser / carrier composition comprises: bracket on the fan side; a diffuser coupled to said bracket on the fan side; said fan-side bracket comprising a flat plate having through-hole openings adjacent to at least one said engine-carrier, wherein at least one foam portion is mounted on said at least one engine-carrier near said carrier opening to absorb noise. Composition according to claim 10, characterized in that said diffuser / carrier composition comprises: a fan-side bracket having at least one motor bracket to support said engine assembly, wherein said bracket-side fan has a through-hole for the engine; a diffuser coupled to said fan-side bracket, wherein said diffuser has a plurality of peripheral openings, said diffuser having a plurality of blades extending from one side to said bracket on the fan side, wherein at least one foam portion is mounted on at least one of said plurality of blades. to absorb noise. Composition according to claim 12, characterized in that said blades are curved and have a concave surface, and said foam is mounted on said concave surfaces. 14. The composition of claim 10, wherein said diffuser / carrier composition comprises: a fan-side bracket having at least one motor bracket to support said engine assembly, wherein the bracket-side bracket has a through-hole; and a diffuser coupled to said fan-side bracket, wherein said diffuser has a plurality of channels extending from one diffuser side toward said fan-side bracket, wherein at least one said foam portion is mounted on at least one of said plurality of blades, that absorbs noise. Composition according to claim 14, characterized in that said channels are curved and have a concave surface and said foam is mounted on said concave surfaces. 16. Low-noise air displacement engine composition, characterized in that it contains: composition of rotary shaft motor; and a fan assembly coupled to said engine assembly, wherein said fan assembly comprises a fan attached to said shaft; a fan-side support to support the engine assembly, wherein said fan-side carrier has through-holes of the carrier and a diffuser coupled to said fan-side carrier, and wherein said diffuser has through-holes, and wherein said fan rotates to form an air stream which travels through said carrier openings and wherein said carrier openings have at least one foam portion to absorb the noise generated by said fan. The composition of claim 16, further comprising: the noise cancellation channel, said engine composition. characterized in that it embraces at least partially 18. The assembly of claim 16, wherein said fan-side carrier has at least one engine carrier, to support said engine assembly, said carrier opening in addition to said at least one engine carrier, wherein foam is mounted on at least one said engine carrier. noise reduction. The assembly according to claim 16, characterized in that the diffuser has a plurality of curved blades that direct the air flow from the fan towards said engine assembly, and that said noise curvature foam is provided. 20. The composition of claim 16, further comprising: a noise attenuation duct, which is located at least partially around said engine assembly, where said duct and at least one foam part have self-extinguishing properties. 21. The composition of claim 16, further comprising: a fan housing which at least partially encloses said fan assembly and is secured to said bracket on the fan side, wherein said fan housing has an inlet. The composition of claim 21, further comprising: a noise attenuation channel positioned around the fan assembly, wherein said fan housing has a plurality of output openings and said channel is positioned in close proximity to said outlet openings. 23. The composition of claim 21, further comprising: a noise attenuation channel having at least one internal flange forming a labyrinthine flow path, wherein said fan housing has a tangential outlet and where said channel fits into said tangential outlet.