Patent Application
20160138606
Embodiments described herein generally relate to fan assemblies. Specific examples may include plenum or plug fan housings and fan assemblies and centrifugal fan assemblies.
Fan impellers are routinely subjected to large forces such as centrifugal forces during operation. These forces may eventually lead to unwanted cracking or fatigue failure in one or more components of the impeller. Improved configuration and methods are desired to improve strength and reliability of impellers.
The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.
The impeller 120 shown in
The fan assembly 100 shown may be used in a number of different configurations, including but not limited to a turbine or plenum fan. The impeller 120 as described in more detail below may be used in any number of different fan configurations. The fan assembly 100 shown in
A welding operation to attach the reinforcing ring 228 may be expensive, and the heat of welding may weaken the plate material and/or introduce unwanted stress concentration features, such as notches or other imperfections from the weld material 230. Additionally, it may be difficult to center the reinforcing ring 228 on the front plate 224, which may lead to an unwanted imbalance in the impeller 200.
The process of forming the circumferential feature 128 provides a number of advantages, both for manufacturability, and physical property advantages. For manufacturability, the process or forming the circumferential feature 128 is less time consuming than welding an additional reinforcing ring 228 onto the front plate, as shown in
In one example, the location of the circumferential feature 128, in between and spaced apart from the outside edge 152 and the inside edge 154, provides a strengthening property to the front plate 124 at a location apart from the edges 152 and 154 that may be prone to failure. The addition of the circumferential feature 128 may reduce or eliminate a likelihood of failure.
Although the circumferential feature 128 is shown formed between and spaced apart from the outside edge 152 and the inside edge 154, the invention is not so limited. In one example, a circumferential feature is formed on the back plate 122, between and spaced apart from an outside edge 125 and the center 121. In one example a circumferential feature as described is formed in both a front plate 124 and a back plate 122. Although a single circumferential feature is shown within the front plate, in other examples multiple circumferential features may be formed for additional strengthening between and spaced apart from the outside edge 152 and the inside edge 154. Multiple circumferential features may also be formed within the back plate 122 in selected examples.
In addition to the formed circumferential feature 128, in selected examples an outer edge feature and/or an inner edge feature may be formed at the outside edge 152 and/or the inside edge 154. Such additional features may further enhance strengthening of the plates, such as the front plate 124 and the back plate 122, without the need for welding additional components onto the plates.
In the example shown, the circumferential feature 128 shows a semi-circular cross section. Other geometries for a cross section of the circumferential feature 128 are also possible, including, but not limited to angled or V shaped cross sections, box cross sections, or other suitable cross sections.
One suitable material for all or a portion of the impeller 120 includes aluminum or an aluminum alloy. Another suitable material for all or a portion of the impeller 120 includes steel. Other formable metallic materials are also within the scope of the invention.
As discussed above, the process of forming the circumferential feature provides a number of advantages, including simplifying manufacture, and providing increased strength. In one example, forming the circumferential feature includes pressing, the circumferential feature into a side of a plate using a die and a press, such as a hydraulic press. In this operation, the entire circumferential feature may be formed in one stroke of the press, which may speed up manufacture.
In one example, the circumferential feature may be spin formed into the plate. Spin forming provides an advantage of ensuring that the circumferential feature is centered about an axis of rotation of the plate, and/or the impeller as assembled. In one example, spin forming includes pressing the plate over a mandrel or die as the mandrel or die is being rotated.
In operation 306, the second circular plate is attached to the number of fan blades in a location opposite and substantially parallel to the first circular plate. In one example, attaching the second circular plate includes welding the second circular plate to the fan blades.
To better illustrate the method and apparatuses disclosed herein, a non-limiting list of examples is provided here:
Example 1 includes a centrifugal fan impeller. The impeller includes a number of circular plates, including a back plate, and a ring shaped front plate, a number of blades coupled between the back plate and the front plate, and a circumferential feature formed within at least one of the plates and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate.
Example 2 includes the centrifugal fan impeller of example 1, wherein the circumferential feature has a semi-circular cross section.
Example 3 includes the centrifugal fan impeller of any one of examples 1-2, wherein the circumferential feature has an angled cross section.
Example 4 includes the centrifugal fan impeller of any one of examples 1-3, wherein the components are formed from steel.
Example 5 includes the centrifugal fan impeller of any one of examples 1-4, wherein the components are formed from aluminum.
Example 6 includes the centrifugal fan impeller of any one of examples 1-5, further including an outer edge formed feature in one or more of the number of circular plates.
Example 7 includes the centrifugal fan impeller of any one of examples 1-6, further including an inner edge formed feature in one or more of the number of circular plates.
Example 8 includes the centrifugal fan impeller of any one of examples 1-7, wherein the number of blades includes airfoil blades.
Example 9 includes the centrifugal fan impeller of any one of examples 1-8, wherein the number of blades includes single thickness blades.
Example 10 includes a fan assembly, including a motor and an impeller coupled to a shaft of the motor. The impeller includes a number of circular plates, including a back plate, and a ring shaped front plate, a number of blades coupled between the back plate and the front plate, a circumferential feature formed within at least one of the plates and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate, and a support frame coupled to the motor.
Example 11 includes the fan assembly of example 10, wherein the shaft of the motor is directly coupled to the impeller.
Example 12 includes the fan assembly of any one of examples 10-11, wherein the impeller is coupled to the shaft of the motor using a drive belt.
Example 13 includes the fan assembly of any one of examples 10-12, wherein the fan assembly is configured as a plenum fan.
Example 14 is a method including attaching a number of fan blades extending substantially normal at periphery of a first circular plate, forming a circumferential feature within a second circular plate and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate, and attaching the second circular plate to the number of fan blades in a location opposite and substantially parallel to the first circular plate.
Example 15 includes the method of example 14, further including forming a circumferential feature within the first circular plate and spaced apart from edges of the plate, the feature extending outward in a direction normal to a plane of the plate.
Example 16 includes the method of any one of examples 14-15, wherein forming a circumferential feature includes forming a semi-circular cross sectioned feature.
Example 17 includes the method of any one of examples 14-16, wherein forming a circumferential feature includes forming multiple circumferential features in a single plate, the multiple features spaced apart from edges of the plate, the multiple features extending outward in a direction normal to a plane of the plate.
Example 18 includes the method of any one of examples 14-17, wherein forming a circumferential feature includes spin forming.
Example 19 includes the method of any one of examples 14-18, wherein forming a circumferential feature includes pressing.
The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.
In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.
The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
