Patent Application
20170227238
A cross-flow or tangential fan is usually long in relation to its diameter, so the flow approximately remains two-dimensional away from its ends. The cross-flow fan uses an impeller with forward curved blades, placed in a housing consisting of a rear wall and a vortex wall. The cross-flow fan may be used in a convection oven where it is exposed to high temperatures sometimes exceeding 800 degrees Fahrenheit.
In an example embodiment, a convection fan is provided. The convection fan may include, but is not limited to, a plurality of blades mounted to a shaft to rotate when the shaft rotates, a guiding plate mounted to partially surround the plurality of blades, and a fan-motor mount. The fan-motor mount may include, but is not limited to, a top plate through which the shaft extends, a bottom plate through which the shaft extends, a motor fastener that mounts a motor to the bottom plate in isolation from the top plate, a guiding plate fastener that mounts the guiding plate to the top plate in isolation from the bottom plate, an insulator between the top plate and the bottom plate, and a plate fastener that mounts the top plate to the bottom plate. The plate fastener may include, but is not limited to, a fastener, and a standoff that surrounds a portion of the fastener between the top plate and the bottom plate and within the bottom plate to provide a thermal break.
In an example embodiment, a convection fan assembly is provided. The convection fan assembly may include, but is not limited to, a motor, a shaft connected to the motor, and a fan. The motor is configured to rotate the shaft. The fan may include, but is not limited to, a plurality of blades mounted to the shaft to rotate when the shaft rotates, a guiding plate mounted to partially surround the plurality of blades, and a fan-motor mount. The fan-motor mount may include, but is not limited to, a top plate through which the shaft extends, a bottom plate through which the shaft extends, a motor fastener that mounts the motor to the bottom plate in isolation from the top plate, a guiding plate fastener that mounts the guiding plate to the top plate in isolation from the bottom plate, an insulator between the top plate and the bottom plate, and a plate fastener that mounts the top plate to the bottom plate. The plate fastener may include, but is not limited to, a fastener, and a standoff that surrounds a portion of the fastener between the top plate and the bottom plate and within the bottom plate to provide a thermal break.
In another example embodiment, a convection oven is provided. The convection oven may include, but is not limited to, the convection fan, a plurality of walls that form an enclosure in which the convection fan is at least partially mounted, and a control to control operation of the convection fan.
Other principal features of the disclosed subject matter will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims.
Illustrative embodiments of the disclosed subject matter will hereafter be described referring to the accompanying drawings, wherein like numerals denote like elements.
Referring to
For example,
In the illustrative embodiment of
As used herein, the term “mount” includes join, unite, connect, couple, associate, insert, hang, hold, affix, attach, fasten, bind, paste, secure, hinge, bolt, screw, rivet, solder, weld, glue, form over, form in, layer, mold, rest on, rest against, abut, and other like terms. The phrases “mounted on”, “mounted to”, and equivalent phrases indicate any interior or exterior portion of the element referenced. These phrases also encompass direct mounting (in which the referenced elements are in direct contact) and indirect mounting (in which the referenced elements are not in direct contact, but are connected through an intermediate element) unless specified otherwise. Elements referenced as mounted to each other herein may further be integrally formed together, for example, using a molding or thermoforming process as understood by a person of skill in the art. As a result, elements described herein as being mounted to each other need not be discrete structural elements unless specified otherwise. The elements may be mounted permanently, removably, or releasably unless specified otherwise.
Use of directional terms, such as top, bottom, right, left, front, back, upper, lower, horizontal, vertical, behind, etc. are merely intended to facilitate reference to the various surfaces of the described structures relative to the orientations introduced in the drawings and are not intended to be limiting in any manner unless otherwise indicated.
Referring again to
Fan 102 may include shaft 208, a bearing housing 110, a top flank 112, a guiding plate 114, a vortex structure 116, a fan-motor mount 118, blades 200, one or more body disks 202, a top disk 204, and a bottom disk 206. A plurality of plate fasteners 308 mount fan 102 to motor 104. Fan 102 may include a greater or a fewer number of components. The one or more components of fan 102 may be formed of one or more materials, such as various metals (i.e., galvanized steel, stainless steel, aluminum, etc.), glass, and/or plastics having a sufficient strength and rigidity as well as thermal and permeability properties sufficient to support the described application.
The blades 200 may be forward curved blades. The blades 200 are elongated and mounted to each other to form a cylinder resulting in a long cylindrical impeller. The blades 200 are inserted through holes in the one or more body disks 202, in top disk 204, and in bottom disk 206. The one or more body disks 202, top disk 204, and bottom disk 206 provide stability to the blades 200. In an alternative embodiment, fan 102 may not include any of the one or more body disks 202.
Shaft 208 extends from motor 104 through fan-motor mount 118 and top flank 112 and into bearing housing 110 at a top of convection fan 100. The bearing housing 110 includes a bearing and associated elements that mount shaft 208 for rotation with a minimum of axial movement. The blades 200 are mounted for rotation with shaft 208.
A housing of fan 102 includes guiding plate 114, fan-motor mount 118, and top flank 112. Guiding plate 114 is mounted between fan-motor mount 118 and top flank 112. Guiding plate 114 may include a curved wall 300, a first mounting flange 210, and a second mounting flange 212. Curved wall 300 partially surrounds the blades 200 to direct air flow generated by rotation of the blades 200. First mounting flange 210 and second mounting flange 212 extend from curved wall 300 and are configured to provide surfaces through which convection fan 100 may be mounted to one or more of the walls of convection oven 1500. For example, first mounting flange 210 and second mounting flange 212 may include holes through which one or more fasteners may be used to mount convection fan 100 to convection oven 1500.
Vortex structure 116 also mounts between fan-motor mount 118 and top flank 112 and is positioned and shaped to direct air flow. Vortex structure 116 may include a bottom vortex flange 302, a first vortex wall 304, a second vortex wall 306, a bottom vortex fastener 214, a bottom screw 216, a top vortex flange (not shown), a top vortex fastener 218, and a top screw 220. First vortex wall 304 and second vortex wall 306 are mounted to each other to form a v-shape that opens outward though other shapes, numbers of walls, orientations, etc. may be used depending on a mounting location and a desired airflow within the enclosure of convection oven 1500. Bottom vortex fastener 214 and bottom screw 216 are mounted to bottom vortex flange 302 to mount first vortex wall 304 and second vortex wall 306 to fan-motor mount 118. Top vortex fastener 218 and top screw 220 are mounted to the top vortex flange to mount first vortex wall 304 and second vortex wall 306 to top flank 112. A fewer or a greater number of fasteners of various types may be used to mount first vortex wall 304 and second vortex wall 306 to top flank 112 and to fan-motor mount 118.
In a cross flow fan, air is drawn in over the entire length of the blades 200. The airflow is diverted and accelerated by first vortex wall 304 and second vortex wall 306. An area between first mounting flange 210 and second vortex wall 306 defines an airflow intake side of convection fan 100. An area between second mounting flange 212 and first vortex wall 304 defines an airflow discharge side of convection fan 100. The airflow also exits over the entire length of the blades 200. First vortex wall 304 directs an approximately uniform laminar airflow out of convection fan 100.
Referring to
Bottom vortex fastener 214 may include a screw 408 and a bottom nut 410 mounted to screw 408 to insure that bottom vortex flange 302 abuts a top surface of bottom flank 400. A nut may similarly be mounted to bottom screw 216. Bottom screw 216 and screw 408 may be identical. The plurality of plate fasteners 308 may each include a standoff 500 and a screw 502 that is inserted through standoff 500 to extend partially from a bottom of motor mount 402. The plurality of plate fasteners 308 mount bottom flank 400 to motor mount 402. The plurality of motor mount housings 406 each cover a motor fastener of a plurality of motor fasteners 504. The plurality of motor fasteners 504 mount motor 104 to motor mount 402 in isolation from bottom flank 400 that may be exposed to a heat within the enclosure of convection oven 1500. A plurality of guiding plate fasteners 506 mount guiding plate 114 to bottom flank 400.
Referring to
First shaft aperture wall 602, the plurality of guiding plate fastener aperture walls 700, the plurality of fan fastener aperture walls 702, and the plurality of vortex fastener aperture walls 704 form openings through top plate 600. First shaft aperture wall 602 is sized, shaped, and positioned to accommodate shaft 208. The plurality of guiding plate fastener aperture walls 700 are each sized, shaped, and positioned to accommodate a fastener shaft 1400 (shown referring to
Referring to
Referring to
Head 900 may include a bottom surface 1000, a side wall 904, and a top surface 906. Side wall 904 extends between bottom surface 1000 and top surface 906. Head 900 may form a hexagon though head 900 may have other shapes in other embodiments. For example, head 900 may form another polygon, a circle, an ellipse, etc.
Body 902 may include a first cylinder wall 908, a second cylinder wall 910, a wall outer surface 912, an inner aperture wall 914, and a score 916. In the illustrative embodiment, body 902 is generally cylindrical though body 902 may have other shapes in other embodiments. For example, body 902 may form a polygon, an ellipse, etc. First cylinder wall 908 extends from and is generally perpendicular to top surface 906. Second cylinder wall 910 extends from first cylinder wall 908. First cylinder wall 908 and second cylinder wall 910 form a cylinder with an inner aperture wall 914 though first cylinder wall 908 has a smaller circumference than second cylinder wall 910. As a result, a shelf (not shown) provides a transition between first cylinder wall 908 and second cylinder wall 910.
Inner aperture wall 914 also extends through head 900 to allow insertion of screw 502 through standoff 500. Outer surface 912 extends between an outer surface of second cylinder wall 910 and inner aperture wall 914. A score 916 is formed as a u-shaped valley in the outer surface of second cylinder wall 910.
Referring to
Head 900 is pressed into bottom plate 604 of motor mount 402 until the shelf formed between first cylinder wall 908 and second cylinder wall 910 abuts a top surface of bottom plate 604 of motor mount 402. Fastener shaft 1408 of screw 502 is inserted within inner aperture wall 914 until screw head 1410 of screw 502 abuts a top surface of top plate 600 of bottom flank 400.
The plurality of plate fasteners 308 are the only components that contact both bottom plate 604 and top plate 600. Top plate 600, bottom vortex fastener 214, bottom screw 216, and the plurality of plurality of guiding plate fasteners 506 are exposed to the potentially high temperatures attained within the enclosure of convection oven 1500. In contrast, motor mount 402 and the plurality of motor fasteners 504 are insulated by insulator 404 from bottom flank 400, and standoff 500 of each of the plurality of plate fasteners 308 provide a thermal break between top plate 600 and bottom plate 604. Motor 104 is thereby protected from the high temperatures and remains cool supporting a longer motor life and an improved motor performance. Additionally, motor 104 may be less expensive because it is not required to tolerate the high temperatures attained within the enclosure of convection oven 1500.
Various types of fasteners may be used to mount the components of convection 100 together. A fewer or a greater number of fasteners further may be used.
The word “illustrative” is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “illustrative” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Further, for the purposes of this disclosure and unless otherwise specified, “a” or “an” means “one or more”. Still further, using “and” or “or” in the detailed description is intended to include “and/or” unless specifically indicated otherwise.
The foregoing description of illustrative embodiments of the disclosed subject matter has been presented for purposes of illustration and of description. It is not intended to be exhaustive or to limit the disclosed subject matter to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed subject matter. The embodiments were chosen and described in order to explain the principles of the disclosed subject matter and as practical applications of the disclosed subject matter to enable one skilled in the art to utilize the disclosed subject matter in various embodiments and with various modifications as suited to the particular use contemplated.
