Patent Application
20210282340
Yard waste clearing devices generally take the form of large vacuums. Such vacuums are heavy and awkward. In order to be mobile, they generally require heavy, loud internal combustion engines, or battery powered motors that only last a short time. Furthermore, they are inefficient at storing yard waste and must be emptied often. It would be advantageous to have a yard waste clearing device that was smaller, more mobile, and more energy and space efficient than existing solutions.
In one aspect, embodiments of the inventive concepts disclosed herein are directed to a yard waste clearing device having a horizontal cross-flow fan blade assembly. The cross-flow fan blade assembly is disposed in a housing that operated in concert to produce an airflow from an inlet portion of the housing, through the cross-flow fan blade assembly, and out an outlet portion with a sufficient flow rate to carry plant matter shredded by the cross-flow fan blade assembly to a storage element.
In a further aspect, the storage element comprises a disposable yard waste bag. A vertical chute from the outlet portion carries the shredded plant matter up to the opening of the yard waste bag so that the yard waste bag may be held vertically.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and should not restrict the scope of the claims. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the inventive concepts disclosed herein and together with the general description, serve to explain the principles.
The numerous advantages of the embodiments of the inventive concepts disclosed herein may be better understood by those skilled in the art by reference to the accompanying figures in which:
Before explaining at least one embodiment of the inventive concepts disclosed herein in detail, it is to be understood that the inventive concepts are not limited in their application to the details of construction and the arrangement of the components or steps or methodologies set forth in the following description or illustrated in the drawings. In the following detailed description of embodiments of the instant inventive concepts, numerous specific details are set forth in order to provide a more thorough understanding of the inventive concepts. However, it will be apparent to one of ordinary skill in the art having the benefit of the instant disclosure that the inventive concepts disclosed herein may be practiced without these specific details. In other instances, well-known features may not be described in detail to avoid unnecessarily complicating the instant disclosure. The inventive concepts disclosed herein are capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.
As used herein a letter following a reference numeral is intended to reference an embodiment of the feature or element that may be similar, but not necessarily identical, to a previously described element or feature bearing the same reference numeral (e.g., 1, 1a, 1b). Such shorthand notations are used for purposes of convenience only, and should not be construed to limit the inventive concepts disclosed herein in any way unless expressly stated to the contrary.
Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by anyone of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
In addition, use of the “a” or “an” are employed to describe elements and components of embodiments of the instant inventive concepts. This is done merely for convenience and to give a general sense of the inventive concepts, and “a” and “an” are intended to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.
Finally, as used herein any reference to “one embodiment,” or “some embodiments” means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the inventive concepts disclosed herein. The appearances of the phrase “in some embodiments” in various places in the specification are not necessarily all referring to the same embodiment, and embodiments of the inventive concepts disclosed may include one or more of the features expressly described or inherently present herein, or any combination of sub-combination of two or more such features, along with any other features which may not necessarily be expressly described or inherently present in the instant disclosure.
Broadly, embodiments of the inventive concepts disclosed herein are directed to a yard waste clearing device having a horizontal cross-flow fan blade assembly. The cross-flow fan blade assembly is disposed in a housing that operated in concert to produce an airflow from an inlet portion of the housing, through the cross-flow fan blade assembly, and out an outlet portion with a sufficient flow rate to carry plant matter shredded by the cross-flow fan blade assembly to a storage element such as a disposable yard waste bag. A vertical chute from the outlet portion carries the shredded plant matter up to the opening of the yard waste bag so that the yard waste bag may be held vertically, utilizing the available storage space more efficiently.
Referring to
Plant matter such as leaves is drawn in through the inlet portion 106 by the airflow 110 and is shredded by the airfoil blades 104. The plant matter may be repeatedly shredded into smaller and pieces within the cross-flow fan blade assembly 102 until small enough to remain effectively suspended within the airflow 110. At that time, the shredded plant matter is carried out the outlet portion 108.
In at least one embodiment, either the inlet portion 106 to receive plant matter or the enclosed cross-flow fan blade assembly 102 may be disposed a specific distance from the ground via the wheels such that the airflow into the inlet portion 106 is sufficient to draw leaves and small plant matter in, but allow heavier material, such as stones or branches to fall out. Alternatively, or in addition, the wheels may be adjustable to raise or lower the housing to increase or decrease airflow proximal to the ground. Alternatively, or in addition, the cross-flow fan opening may include a guard to exclude matter above a certain size to prevent damage to the cutting blades.
In at least one embodiment, the cross-flow fan blade assembly may be 10 inches wide, but additional embodiments are envisioned. In at least one embodiment, the cross-flow fan blade assembly may be modular to allow increased width via additional cutter sections. A 15-inch embodiment may have four rotors with three cutter sections. A 20-inch embodiment may include additional rotor and cutting section. The disc diameter may be 3.6 inches. By comparison the same system configured with 6-inch diameter discs may have three rotors and two cutting sections.
A cross-flow fan blade assembly 102 according to exemplary embodiments may include airfoil blades 104 that are manufactured using a low cost continuous in-line process from inexpensive coils of strip steel, such as used in band saw blades, utility knife blades, or razor blades. Blade thickness is thin (less than 0.075 inches). Thin blades are advantageous to blade longevity. In some embodiments, a cross-flow fan blade assembly 102 with unsharpened blades between 0.032 inches and 0.035 inches thick and having no cutting edge were shown to be sharper than slightly used rotary blades.
In at least one embodiment, each airfoil blade 104 of a cross-flow fan blade assembly 102 comprises a hardened cutting edge with Rockwell hardness above 60 to a depth of 0.035 inches, and a softer body of Rockwell hardness below 58 for the remainder of the blade.
Referring to
In at least one embodiment, the yard waste bag platform may include structures to secure the yard waste bag 212 in place, and hold the yard waste bag opening 210 open. Such structures may include adjustable metal frame elements positively attaching the yard waste bag 212 to the chute 206.
Furthermore, the cross-flow fan housing 202 may include wheels to roll along the ground and collect plant matter at aa height determined by a desired airflow into the housing. Such wheels may be adjustable to control the airflow pressure. In such embodiment, shredded plant matter may need to travel a significant vertical distance to enter an upright yard waste bag 212. The cross-flow fan must therefore be configured for sufficient airflow, and sufficient shredding efficiency, to produce shredded plant matter that can be carried that vertical distance by the airflow to reach the yard waste bag. In at least one embodiment, the airflow may be sufficient to draw unshredded plant matter from the ground, a short distance to a cross-flow fan proximal to the ground, and propel shredded plant matter a larger vertical distance.
Such embodiments are useful for efficiently disposing of plant matter, and increasing its overall density (via shredding) to more efficiently use the yard waste bags 212. Furthermore, having the cross-flow fan and corresponding power supply close to the ground may offer improved safety and comfort as compared to carrying a yard waste clearing device 200. Also, having a known disposition of the yard waste bag 212 relative to the cross-flow fan allows the chute 206 to be solid and fixed, which may produce smoother airflow and prevent buildup inside the chute 206.
Referring to
The cross-flow fan housing 302 may include wheels that allow an inlet portion 314 to be pivoted about the wheels. The inlet portion 314 may be forward facing to more easily allow plant matter to enter the inlet portion 314 with a lower overall airflow.
Such embodiments are useful for efficiently disposing of plant matter, and increasing its overall density (via shredding) to more efficiently use the yard waste bags or storage chamber 312. Furthermore, having the cross-flow fan and corresponding power supply close to the ground may offer improved safety and comfort as compared to carrying a plant matter vacuum device.
Referring to
In at least one embodiment, the distance from the center of rotation to a proximal edge of the cutting blade 402 is substantially similar to the distance from the center of rotation to a distal edge of the corresponding diverter blade 404. In at least one embodiment, the angular distance of the diverter blade 404 from the cutting blade 402 as measured from the center of rotation may be a function of the front angle of the cutting blade.
In at least one embodiment, cutting blades 402 with a front angle between 26 and 33 degrees demonstrated good cut quality and good anti-sticking characteristics. Furthermore, anti-sticking characteristics are best with a rear angle between 85 and 95 degrees.
In at least one embodiment, a cutting blade 402 front angle of 33 degrees with a corresponding diverter blade 404 may be optimal. Cut quality may be suboptimal with a front angle greater than 35 degrees or less than 23 degrees.
Referring to
Cross-flow fan cutting assemblies may utilize harder blades as they operate at slower speeds, which increases blade life. Furthermore, cross-flow fan cutters may be designed to produce an airflow that prevents material sticking to the blades such as through the addition of diverter blades, hence they are easier to maintain.
In at least one embodiment, a cross-flow fan having blades with a leading cutting edge and an airfoil cross-section is disposed in a plant matter shredding device (for example, in
Referring to
While the embodiments discussed herein have been generally directed to plant cutting/shredding, other embodiments may be useful in non-plant applications. For example, some embodiments may be useful in fluid movement applications where material in the fluid may need to be reduced. Other industrial applications are envisioned where flow is desirable in an environment where material in the flow may need to be reduced.
It is believed that the inventive concepts disclosed herein and many of their attendant advantages will be understood by the foregoing description of embodiments of the inventive concepts disclosed, and it will be apparent that various changes may be made in the form, construction, and arrangement of the components thereof without departing from the broad scope of the inventive concepts disclosed herein or without sacrificing all of their material advantages; and individual features from various embodiments may be combined to arrive at other embodiments. The form herein before described being merely an explanatory embodiment thereof, it is the intention of the following claims to encompass and include such changes. Furthermore, any of the features disclosed in relation to any of the individual embodiments may be incorporated into any other embodiment.
The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional App. No. 62/987,123 (filed Mar. 9, 2020), which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62987123 | Mar 2020 | US |
