Fan assembly

A fan assembly in which all of the major structural components of the assembly are mechanically fastened together by non-welding means, such as mechanical fasteners, is disclosed. The disclosure also relates to a fan assembly in which the major structural components have planar segments separated by bend lines that approximate a curved shape, and that can be formed, for example, by a press brake machine. Such a construction can eliminate the necessity for rolling, welding, and painting of the structural components of the fan assembly.

TECHNICAL FIELD

This disclosure relates to fan assemblies for providing an airflow stream, and particularly to in-line fan assemblies configured to provide an axial airflow through an outer chamber.

BACKGROUND

Fan assemblies for providing an airflow stream are known. One type of fan assembly is an in-line fan assembly including a housing containing a fan rotor for moving an airflow stream through the housing. Many in-line fan assembly housings are cylindrical in shape which requires specialized manufacturing equipment and processes in addition to limiting the types of materials that can be used. For example, in order to construct a traditional cylindrical fan housing, several pieces of equipment are required including: a roller, a seam welder, and a flanger. Secondary components that require connection to the main structure (i.e. motor plate, bearing plate, turning vanes, etc.) can also require welding. Due to the significant welding amounts, tubular designs are traditionally constructed from hot-rolled steel, thereby additionally requiring paint. Other higher strength materials, such as stainless steel, are not as frequently used due to the difficulty of manufacturing tubes and curved shapes from such materials. Accordingly, improvements in fan assemblies are desired.

SUMMARY

This disclosure relates to a fan assembly in which none of the major structural components of the assembly are fastened together by welding and are instead mechanically fastened together. Because the major structural components are not fastened together by welding, painting of the components can be avoided. The disclosure also relates to a fan assembly in which none of the major structural components has a curved shape formed by a rolling process. Instead, curved shapes of the major structural components are approximated by planar segments separated by bend lines that can be formed, for example, by a press brake machine.

In one aspect, the fan assembly has an outer chamber and a rotatable fan assembly disposed within the outer chamber. The outer chamber can define a longitudinal axis extending between a first open end and an opposite second open end. As configured, the rotatable fan assembly moves an airflow stream through the outer chamber from the first open end towards the second open end.

In one aspect, the outer chamber has at least five planar sidewall segments that together form a tubular structure having a polygonal cross-sectional shape. In one embodiment, the outer chamber is formed by a first section and a second section that are connected to each other by mechanical fasteners. The first and second open ends can be provided with flanges to which adapter rings can be connected. Where the rotatable fan assembly includes a mixed-flow type fan rotor, an inlet cone may be installed at the first open end of the chamber adjacent the adapter ring.

The fan assembly may also include an inner chamber having a plurality of planar sidewall segments that together form a tubular structure with a cross-sectional polygonal shape, wherein the inner chamber is disposed within the outer chamber and defines a longitudinal axis extending between a first open end and an opposite second open end. The first open end of the inner chamber may be mechanically secured to an end plate to prevent the airflow stream from passing through the inner chamber thereby ensuring that the airflow stream passes in the interstitial area between the inner and outer chambers.

A tail cone assembly may be provided that is mechanically fastened to the second open end of the inner chamber. In one embodiment, the tail cone assembly has at least five planar sidewall segments that together form a tapered tubular structure with a generally polygonal cross-sectional shape with a first open end and a second open end. The tail cone assembly may also have first and second sections that are mechanically fastened to each other and an end plate secured to one of the first and second open ends.

A plurality of turning vanes may also be provided in the fan assembly. The turning vanes function to straighten airflow leaving the rotatable fan assembly and also structurally secure the inner chamber to the outer chamber. As configured, the turning vanes extend from the outer chamber and towards the inner chamber. In one embodiment, each turning vane has a main body with a plurality of planar segments separated by bend lines. The turning vanes may also be provided with tabs or other structures such that they can be mechanically fastened to the inner and/or outer chambers.

The fan assembly may also be provided with a motor assembly including a motor plate, a motor cover, and a motor seal, each of which can be mechanically fastened to the outer chamber. Mounting legs may also be provided for the fan assembly and mechanically fastened to the outer chamber. A bearing plate may also be provided within the inner chamber that is configured to support the rotatable fan assembly and to secure the inner chamber to the outer chamber. In one embodiment, the bearing plate may be mechanically fastened to the inner chamber and to the outer chamber.

DETAILED DESCRIPTION

Referring now toFIG. 1, an example fan assembly100is shown. Fan assembly100is for providing means for transporting air, such as through a ducting system (not shown) relating to a building heating, ventilation, air conditioning, recirculation, and/or exhaust air system. As shown, fan assembly100is constructed such that the major structural components of the fan assembly100have a segmented shape that can be secured together without welding. By use of the term “major structural components” it is intended to include the outer chamber200, the inner chamber100, and the bearing plate312of the fan assembly100, each of which will be discussed in greater detail herein. In embodiments where the turning vanes500secure the inner chamber100to the outer chamber200, the turning vanes500can also be considered a major structural component. In the embodiment shown, fan assembly100is a mixed-flow type fan assembly having a mixed-flow type fan rotor102supported by a shaft104that is driven by a belt108connected to an electric motor106. Alternatively, the fan rotor can be another type of fan rotor such as an axial fan rotor. Also, the shaft104can be configured to be directly driven by the electric motor106instead of indirectly driven by the belt108.

By use of the term “segmented shape” it is meant to include those shapes that are formed by planar surfaces or segments separated by bend lines that approximate a curve in contrast to shapes that are formed with a continuously curved surface. One example of a segmented shape is a generally polygonal shape. By use of the terms “mechanical fastener”, “mechanically fastened”, and “non-welded means” it is intended to include any method of attachment between two components other than welding. Non-limiting examples of mechanical fasteners are bolts, screws, rivets, clips, and latches.

Fan assembly100includes an outer chamber200configured for housing a number of components, for example a fan rotor102. As shown, outer chamber200includes a first section202and a second section204that cooperatively form a tubular structure having a generally polygonal cross-sectional shape extending between a first open end206and a second open end208, and defining a longitudinal axis L. Although the outer chamber200is shown as having a generally octagonal shape with 8 planar sections, other generally polygonal shapes are possible, such as pentagonal (five sides), hexagonal (six sides), heptagonal (seven sides), decagonal (ten sides), and dodecagonal (twelve sides) shapes which progressively define cross-sectional shapes that approximate a circle. Additionally, although outer chamber200is shown as having two sections202,204, more sections may be provided.

In the embodiment presented in the drawings, and as most easily seen in the schematic representation shown atFIG. 7, each of the first and second sections202,204is provided with five planar sections separated by bend lines that together form a generally octagonal cross-sectional shape. In particular, the outer chamber first section202is provided with planar sections202a,202b,202c,202d,202e(collectively referred to as202a-e) separated by bend lines202f,202g,202h, and202i(collectively referred to as202f-i). Similarly, the outer chamber second section204is provided with planar sections204a,204b,204c,204d,204e(collectively referred to as204a-e) separated by bend lines204f,204g,204h, and204i(collectively referred to as204f-i). As shown, planar sections202b-dand204b-deach have a length L1while planar sections202a,202e,204a, and204eeach have a length L2that is about one half the length of L1. This construction allows for planar sections202aand204ato form one of the full sides of the outer chamber202and for planar sections202eand204eto cooperatively form another one of the full sides of the outer chamber202. It is noted that sections202a/202aand202e/204edo not have to have the same length as each other as long as their combined lengths are equal to L1. However, manufacturing costs can be reduced where L1is about half L2as the first and second sections202,204can then be identical to each other. The angles between each adjacent full side (e.g. angle between204cand204d, angle between204a/202aand202b, etc.) are also shown as being an equal angle a1. As the embodiment shown for the outer chamber200forms a generally octagonal shape, the angle a1is about 135 degrees.

Each of the outer chamber first and second sections202,204are provided with first and second side flanges that serve as a mating point for the two sections. In particular, the outer chamber first section202is provided with a first side flange202jthat extends the length of the first section202and is separated from adjacent planar section202aby a bend line202l. The outer chamber first section202is also provided with a second side flange202kthat extends the length of the first section202and is separated from adjacent planar section202eby a bend line202m. Similarly, the outer chamber second section is provided with a first side flange204ithat extends the length of the second section204and is separated from adjacent planar section204aby a bend line204l, and is provided with a second side flange204kthat extends the length of the second section204and is separated from adjacent planar section204eby a bend line204m.

With reference toFIG. 8, each of the first and second outer chamber sections202,204can be formed from an initially flat sheet of metal by bending the flat sheet of metal at bend lines202i/204i,202f/204f,202g/204g,202h/204h,202i/204i,202l/204l, and202m/204m. In one approach, the initially flat sheet can be bent at the bend lines by a press brake machine.

As most easily seen atFIG. 7, the outer chamber200is formed by joining the first section202to the second section204such that the first side flanges202j,204jare aligned and in contact with each other and such that the second side flanges202k,204kare aligned and in contact with each other. Once properly aligned, the aligned side flanges can then be secured together, for example with mechanical fasteners210. Accordingly, the aforementioned design and construction of the outer chamber200has the advantage of being formable through non-welding means. Alternatively, an adhesive may be used instead of mechanical fasteners for certain fan assembly sizes and applications. The first and second sections202,204may also be secured by welding, for example by spot welding. However, as discussed previously, the use of certain welding processes can increase complexity and cost in manufacturing in that painting can be required and in that a metal(s) for the outer chamber200must be carefully chosen that is suitable for both bending and the selected welding process.

As most easily viewed atFIGS. 3 and 4, the outer chamber200may be provided with a first end flange212adjacent the first open end and a second end flange214adjacent the second open end. The first end flange212is for providing support for a first adapter ring216and an inlet cone218. The inlet cone218is shaped to provide a smooth pathway into the center portion of the fan rotor102. The second end flange214is for providing support for a second adapter ring220. As shown, the first and second end flanges212,214are formed by a plurality of tab sections222, each of which is shown as being formed integrally with a corresponding planar section (202a-e,204a-e) and bent about 90 degrees with respect to the planar section (202a-e,204a-e). Although a tab section222is shown at each planar section (202a-e,204a-e), few tab sections may be provided. As shown, the adapter rings216,220and the inlet cone218are attached to the respective tab sections222by mechanical fasteners224.

Where the outer chamber200is to be supported from below, mounting legs226may be provided on the outer chamber200and mechanically fastened to the second section204. Where the outer chamber200is to be supported from above, the outer chamber may be provided with hanger mounts configured to accept support rods and vibration isolators, where desired.

The outer chamber200can also be configured to support a motor plate228and a belt seal230for respectively supporting a motor106and housing a belt108. Additionally, a motor cover232can be provided to house and protect the motor106. As shown, each of the motor plate228, the belt seal230, and the motor cover232are mechanically fastened to the outer chamber first section202without the need for welding.

Fan assembly100also includes an inner chamber300. The inner chamber300is located within the outer chamber200and is primarily configured for supporting the fan rotor102of the fan assembly and for defining an airflow path between the inner and outer chambers300,200. As shown, inner chamber300includes a first section302and a second section304that cooperatively form a tubular structure having a generally polygonal cross-sectional shape extending between a first open end306and a second open end308. Although the inner chamber300is shown as having a generally octagonal shape with 8 planar sections, other generally polygonal shapes are possible, such as pentagonal (five sides), hexagonal (six sides), heptagonal (seven sides), decagonal (ten sides), and dodecagonal (twelve sides) shapes which progressively define cross-sectional shapes that approximate a circle. Additionally, although inner chamber300is shown as having two sections302,304, more sections may be provided.

In the embodiment presented in the drawings, and as most easily seen in the schematic representations shown atFIGS. 9-10, each of the first and second sections302,304is provided with five planar sections separated by bend lines that together form a generally octagonal cross-sectional shape. In particular, the inner chamber first section302is provided with planar sections302a,302b,302c,302d,302e(collectively referred to as302a-e) separated by bend lines302f,302g,302h, and302i(collectively referred to as302f-i). Similarly, the inner chamber second section304is provided with planar sections304a,304b,304c,304d,304e(collectively referred to as304a-e) separated by bend lines304f,304g,304h, and304i(collectively referred to as204f-i). As shown, planar sections302b-dand304b-deach have a length L3while planar sections302aand302ehave a length L4and planar sections304aand304ehave a length L5wherein length L4and L5together, in addition to the thickness of the bearing plate, generally equal length L3. This construction allows for planar sections302aand304ato form one of the full sides of the inner chamber302and for planar sections302eand304eto cooperatively form another one of the full sides of the inner chamber302. It is noted that sections302a/302eand304a/304ecould have identical lengths as is shown for the outer chamber. The angles between each adjacent full side (e.g. angle between304cand304d, angle between304a/302aand302b, etc.) are also shown as being an equal angle a2. As the embodiment shown for the inner chamber300forms a generally octagonal shape, the angle a2is about 135 degrees.

Each of the inner chamber first and second sections302,304are provided with first and second side flanges that serve as a mating point for the two sections. In particular, the inner chamber first section302is provided with a first side flange302jthat extends the length of the first section302and is separated from adjacent planar section302aby a bend line302l. The inner chamber first section302is also provided with a second side flange302kthat extends the length of the first section302and is separated from adjacent planar section302eby a bend line202m. Similarly, the inner chamber second section is provided with a first side flange304ithat extends the length of the second section304and is separated from adjacent planar section304aby a bend line304l, and is provided with a second side flange304kthat extends the length of the second section304and is separated from adjacent planar section304eby a bend line304m.

As with the outer chamber200, each of the first and second outer chamber sections302,304can be formed from an initially flat sheet of metal by bending the flat sheet of metal at bend lines302i/304i,302f/304f,302g/304g,302h/304h,302i/304i,302l/304l, and302m/304m. In one approach, the initially flat sheet can be bent at the bend lines by a press brake machine.

As most easily seen atFIG. 10, the inner chamber300is formed by joining the first section302to the second section304such that the first side flanges302j,304jare aligned and in contact with the bearing plate312and such that the second side flanges302k,304kare aligned and in contact with the bearing plate312. Once properly aligned, the aligned side flanges and bearing plate312can then be secured together, for example with mechanical fasteners310. Accordingly, the aforementioned design and construction of the inner chamber300has the advantage of being formable through non-welding means. It is to be understood that, where a bearing plate does not extend all the way through the inner chamber, the side flanges can be directly attached to one another. It is also noted that an adhesive may be used instead of mechanical fasteners for certain fan assembly sizes and applications. The first and second sections302,304may also be secured by welding, for example by spot welding. However, as discussed previously, the use of certain welding processes can increase complexity and cost in manufacturing in that painting can be required and in that a metal(s) for the inner chamber300must be carefully chosen that is suitable for both bending and the selected welding process.

As shown, the inner chamber300houses and supports a bearing plate312which includes planar segments separated by bend lines and which includes a perimeter flange, both of which can be formed by, for example, a brake press machine. The bearing plate312is configured to support bearing assemblies112which in turn support rotating shaft104to which a belt pulley/sheave110and a rotatable fan rotor102are attached. As shown, the bearing plate312is attached to the inner chamber300by mechanical fasteners310whereby welding is not required. For example, in the embodiment shown, a middle section312aof the bearing plate312is mechanically fastened via fasteners310to the inner chamber300between side flanges302j/304jand side flanges302k/304k. Also, upwardly bent end sections312bof the bearing plate312are secured to the planar sections202b,202dof the outer chamber200via mechanical fasteners313. This construction allows for the bearing plate312to structurally secure the inner chamber300within the outer chamber200.

The inner chamber300may also be provided with tab sections314on one or more of the planar sections302a-e,304a-eat the first and second open ends306,308that may be used for connection to an end plate302and a tail cone assembly400, respectively. As shown, the end plate302is mechanically fastened to the inner chamber300via the tab sections314and fasteners315so as to cover the first open end306. In operation, the end plate302prevents air from flowing through the interior of the inner chamber300and instead directs the airflow to the interstitial space between the inner and outer chambers200,300. As explained herein, the tail cone assembly400covers the second open end308of the inner chamber300.

At the second open end308of the inner chamber300, a tail cone assembly400may be provided and secured via fasteners315at tab sections314. The tail cone assembly400functions to cover the second open end308of the inner chamber and to provide an aerodynamic transition for the airflow stream passing beyond the inner chamber300.

The tail cone assembly400shares many of the same features as the inner and outer chambers300,200in that the tail cone assembly400can be formed by folding initially flat sheets of metal and joining the structures together with non-welding means to form a tubular structure. Accordingly, the various planar sections and bend lines for the tail cone assembly400do not need to be discussed with regard to these similar features. With regard to the similar features, the descriptions for the inner and outer chambers200,300are hereby incorporated by reference into the description for the tail cone assembly400.

The tail cone assembly400is different from the outer and inner chambers200,300in that a polyhedral shape is formed such that the tail cone assembly400tapers from a first open end416matching the second open end308of the inner chamber300to a second open end418. The tail cone assembly also differs in that four separate sections402,404,406,408are joined together instead of only two sections although fewer or more sections may be utilized. In the particular embodiment shown, the sections402-408are each identical, thus allowing for the tail cone assembly400to be produced from four of the same type of piece part. This approach reduces manufacturing costs. It is noted that sections402and404are shown as being provided with notched portions414which may be either formed after the section piece is produced or as section pieces that are non-identical to sections406and408. Although the assembled tail cone assembly400is shown as defining a generally octagonal shape with 8 planar sections, other generally polygonal shapes are possible, such as pentagonal (five sides), hexagonal (six sides), heptagonal (seven sides), decagonal (ten sides), and dodecagonal (twelve sides) shapes which progressively define cross-sectional shapes that approximate a circle.

In the embodiment presented in the drawings, and as most easily seen in the schematic representations shown atFIG. 11, each of the sections402-408is provided with three planar sections separated by bend lines that together form a generally octagonal cross-sectional shape. In particular, each section402-408is provided with planar sections400a,400b,400c(collectively referred to as400a-c) separated by bend lines400d,400e(collectively referred to as400d-e). As shown, each planar section400bhas a length L6while each planar section302a,302chas a length L7, wherein length L7is generally one half of length L6. The angles between each adjacent side400a-400care also shown as being an equal angle a3. As the embodiment shown for the tail cone assembly400forms a generally octagonal shape, the angle a3is about 135 degrees.

Each of the tail cone assembly sections402-408is provided with first and second side flanges that serve as a mating point for the adjacent sections. In particular, a first side flange400fis provided that extends the length of the section and is separated from adjacent planar section400aby a bend line400h. Each section402-408is also provided with a second side flange400gthat extends the length of the section and is separated from adjacent planar section400cby a bend line400i.

As with the inner and outer chambers200,300, each section402-408can be formed from an initially flat sheet of metal by bending the flat sheet of metal at bend lines400h,400d,400e, and400i. In one approach, the initially flat sheet can be bent at the bend lines by a press brake machine.

As most easily seen atFIG. 11, the tail cone assembly is formed by joining the sections402-408at the respective first and second side flanges400f,400gsuch that the flanges are aligned and in contact with each other. Once properly aligned, the aligned side flanges400f,400gcan then be secured together, for example with mechanical fasteners410. Accordingly, the aforementioned design and construction of the tail cone assembly400has the advantage of being formable through non-welding means. Alternatively, an adhesive may be used instead of mechanical fasteners for certain fan assembly sizes and applications. The sections402-408may also be secured by welding, for example by spot welding. However, as discussed previously, the use of certain welding processes can increase complexity and cost in manufacturing in that painting can be required and in that a metal(s) for the tail cone assembly400must be carefully chosen that is suitable for both bending and the selected welding process.

The tail cone assembly400may also be provided with folded tab or flange sections420,412on one or more of the planar sections400a-cat the first and second open ends416,418that may be used for connection to the inner chamber300and an end plate422, respectively. As shown, the end plate422is mechanically fastened to the tail cone assembly400via the tab sections422so as to cover the second open end418. In operation, the end plate418prevents air from flowing backwards through the interior of the inner chamber300via the tail cone assembly400.

With reference toFIGS. 6 and 12, additional detail regarding the turning vanes500can be seen. As configured, each of the turning vanes500is configured with a plurality of planar sections502separated by bend lines504. Additionally, tabs506may be provided along the sides of the turning vanes500to facilitate mounting of the turning vane500. In one embodiment, each of the turning vanes can be formed from an initially flat sheet of metal by bending the flat sheet of metal at bend lines504. In one approach, the initially flat sheet can be bent at the bend lines504by a press brake machine. Once formed, the turning vanes500can be mounted to one or both of the inner chamber300and the outer chamber200. As shown, the turning vanes500are secured to the outer chamber200via fasteners511and spaced away from the inner chamber300. However, it is to be understood that the turning vanes could be secured to the inner chamber300and be spaced from the outer chamber, or be secured to both the inner and outer chambers200,300to structurally secure the inner chamber300to the outer chamber200. With reference toFIG. 12, it can be seen that a turning vane500extends from each of the full sides of the inner chamber300to a corresponding parallel full side of the outer chamber200such that each turning vane500is perpendicular to the full sides of the chambers200,300to which it is attached. As mentioned previously, the turning vanes500also function to straighten airflow leaving the rotatable fan assembly100.