Patent Publication Number: US-2023149956-A1

Title: Portable granular particle spreader

Description:
FIELD OF THE INVENTION 
     The present invention is directed to granular particle spreaders, and more particularly, to portable granular particle spreaders. 
     BACKGROUND OF THE INVENTION 
     Spreaders are commonly used to spread granular particles or material such as seed, weed control pre-emergent, or fertilizer as part of a lawn care, vegetable farming, gardening, and the like. One conventional spreader includes an open hopper for receiving the granular material extending to a handle at the base of the hopper that is adapted to be secured in the grasp of one hand of an operator. The operator’s other hand is then required to turn a crank in order to urge a distributor into rotational movement to laterally dispense the granular material from the spreader onto the lawn. Unfortunately, such an arrangement is inefficient, as the hopper size must be small to permit the operator to carry and dispense the granular material, requiring many return trips to refill the hopper, quickly tiring the operator. Alternately, there are spreaders having a pair of wheels positioned at opposed ends of an open hopper for rotatably supporting the hopper. A push/pull bar or handle is connected to the hopper, permitting the spreader wheels to roll over and dispense granular material onto the lawn as a result of the operator walking over the lawn while pushing/pulling the handle. The wheeled spreader can accommodate a larger hopper than a hand-carried/supported spreader, and can incorporate an adjustable dispenser mechanism, typically a spring or cable arrangement adapted for providing an adjustable size opening that is positioned vertically beneath the hopper. However, despite the adjustability of the size of the opening, accurate granular material dispensing may be difficult to achieve, as the dispensing material opening is generally obscured by the hopper itself, making it difficult to visually determine the application rate. Moreover, uneven terrain and/or terrain with closely spaced shrubs or other obstacles, may further complicate the use of the heavy and cumbersome wheeled spreaders. 
     There is a need for a portable spreader that does not suffer for these drawbacks. 
     SUMMARY OF THE INVENTION 
     Applicant has invented an improved portable spreader incorporated in a backpack arrangement that permits use of a relatively large enclosed hopper in combination with a pressurized air source and distribution system that permits accurate placement of granular particles or material, while reducing operator fatigue. Spreaders are commonly used to spread granular material such as seed, weed control pre-emergent, or fertilizer as part of a lawn care, vegetable farming, gardening, and the like, and other applications, including but not limited to granular snow-melt material. 
     In one embodiment, a portable granular material spreader includes an enclosure having an inlet and an outlet, the enclosure adapted to receive the granular material through the inlet and dispense the granular material from the enclosure through the outlet. The portable granular material spreader further includes a pressurized air source for providing pressurized air. The portable granular material spreader further includes a body having a chamber having a first passageway, a second passageway, and a third passageway, the chamber containing a distributor therein, the first passageway in fluid communication with the outlet to receive the granular material by virtue of gravity from the outlet with the distributor controlling a flow rate of the granular material in the chamber, the second passageway in fluid communication with the pressurized air source, and the third passageway for discharging the granular material entrained in the pressurized air from the pressurized air source, the distributor substantially isolating the first passageway from the second passageway and the third passageway. The portable granular material spreader further includes a conduit having opposed ends, the conduit in fluid communication with the second passageway and the enclosure, the conduit end positioned in the enclosure being sufficiently distal from the enclosure outlet to not result in aerating the granular material proximate the outlet while preventing a reverse flow of the granular material at the enclosure outlet during operation of the spreader. 
     In another embodiment, a portable granular material spreader includes an enclosure having an inlet and an outlet, the enclosure adapted to receive the granular material through the inlet and dispense the granular material from the enclosure through the outlet. The portable granular material spreader further includes a pressurized air source for providing pressurized air. The portable granular material spreader further includes a body having a chamber having a first passageway, a second passageway, and a third passageway, the chamber containing a distributor therein, the first passageway in fluid communication with the outlet to receive the granular material by virtue of gravity from the outlet with the distributor controlling a flow rate of the granular material in the chamber, the second passageway in fluid communication with the pressurized air source, and the third passageway for discharging the granular material entrained in the pressurized air from the pressurized air source, the distributor substantially islolating the first passageway from the second passageway and the third passageway. The portable granular material spreader further includes a conduit having opposed ends, the conduit in fluid communication with the second passageway and the enclosure, the conduit end positioned in the enclosure being sufficiently distal from the enclosure outlet to not result in aerating the granular material proximate the outlet while preventing a reverse flow of the granular material at the enclosure outlet during operation of the spreader. The portable granular material spreader further includes a wand-type second distributor having a flexible portion connected to the body outlet and terminating at a rigid portion extending to a fitting adapted to distribute the granular material from an end of the rigid portion opposite the flexible portion. The rigid portion further includes a handle including a first control for controlling a flow of pressurized air from the pressurized air source, and a second control for controlling a speed of the distributor, the first control and the second control operating independently from one another. 
     In yet another embodiment, a portable granular material spreader includes an enclosure having an inlet and an outlet, the enclosure adapted to receive the granular material through the inlet and dispense the granular material from the enclosure through the outlet; The portable granular material spreader further includes a pressurized air source for providing pressurized air. The portable granular material spreader further includes a body having a chamber having a first passageway, a second passageway, and a third passageway, the chamber containing a distributor therein, the first passageway in fluid communication with the outlet to receive the granular material by virtue of gravity from the outlet with the distributor controlling a flow rate of the granular material in the chamber, the second passageway in fluid communication with the pressurized air source, and the third passageway for discharging the granular material entrained in the pressurized air from the pressurized air source, the distributor substantially islolating the first passageway from the second passageway and the third passageway. The portable granular material spreader further includes a conduit having opposed ends, the conduit in fluid communication with the second passageway and the enclosure, the conduit end positioned in the enclosure being sufficiently distal from the enclosure outlet to not result in aerating the granular material proximate the outlet while preventing a reverse flow of the granular material at the enclosure outlet during operation of the spreader. The portable granular material spreader further includes a wand-type second distributor having a flexible portion connected to the body outlet and terminating at a rigid portion extending to a fitting adapted to distribute the granular material from an end of the rigid portion opposite the flexible portion. The rigid portion further includes a handle including a first control for controlling a flow of pressurized air from the pressurized air source, and a second control for controlling a speed of the distributor, the first control and the second control operating independently from one another. The first control and the second control are adapted to be operated with a single hand. 
     Other features and advantages of the present invention will be apparent from the following more detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an upper perspective view of an exemplary portable granular material spreader. 
         FIG.  2    is a partial upper perspective cutaway view of the material spreader of  FIG.  1   . 
         FIG.  3    is an enlarged partial upper perspective cutaway view of the material spreader of  FIG.  2   . 
         FIG.  4    is a cross section taken along line 4-4 of the material spreader of  FIG.  2   . 
         FIG.  5    is a cross section taken along line 5-5 of the material spreader of  FIG.  2   . 
         FIG.  6    is a schematic of an exemplary electrical circuit of a material spreader. 
         FIG.  7    is a portion of an exemplary distribution system of a material spreader. 
         FIG.  8    is a portion of an exemplary distribution system of a material spreader. 
     
    
    
     Wherever possible, the same reference numbers will be used throughout the drawings to represent the same parts. 
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG.  1    shows a portable granular particle spreader  10  including a frame  12  having a plurality of interconnected panels  14 ,  16 ,  18 ,  29 ,  22  which collectively define a compact cubical housing  25  for protecting spreader components therein, as well as forming a peripheral seal at an upper extent with a hopper or enclosure  50  for receiving granular particles therein. As shown, panel  14  of frame  12  includes a stiffening flange  34  providing strength and structural stability for supporting both hopper or enclosure  50  on one side (via fasteners  52  ( FIG.  4   )) and loops of a pair of shoulder straps  46  on the other side of panel  14 , which shoulder straps  46  extending through corresponding slots  44  formed in panel  14 , and a slot  48  for permitting the spreader to be lifted from a single hand hold. As further shown, fasteners  32  are utilized to secure panel  16  to flange  34  and  38  ( FIG.  2   ) via openings  36  formed therein, such as threaded openings. Similarly, fasteners  32  may be utilized to secure panel  24  to flange  40  ( FIG.  2   ), as well as securing panel  20  to flange  42  ( FIG.  2   ). As shown, panel  24  is secured over panel  18  by hooks  30  of latches  28  (e.g., over-center latches) engaging corresponding slots formed in panel  24 . However, other constructions are also contemplated by the invention. For example, in one embodiment, one or more panels may be formed of a single piece. In one embodiment, one or more panels may be formed as a single piece with the enclosure, such panel  14  and enclosure  50 . In one embodiment, fasteners such as latches may be used such that assembly/disassembly of one or more panel(s), up to and including all of the panels may be achieved without tools (i.e., by hands only). 
     As shown in  FIG.  2   , enclosure  50  includes an inlet  54  that is vertically above an outlet  56 , with inlet  54  adapted to form a substantial fluid tight seal with a lid  60 . That is, lid  60  and inlet  54  are generally intended to be sufficiently engaged (e.g., threadedly engaged, possibly in combination with seals such as O rings (not shown)) such as to be sealed from or otherwise impervious to moisture and isolated from the relative atmospheric pressure from a surrounding environment  62  for reasons to be discussed later. Enclosure  50  is adapted to receive granular material  58  through inlet  54  (followed by installing/engaging lid  60  with inlet  54  to establish the desired seal therebetween) and dispense granular material or granular particles  58  by virtue of gravity from enclosure  50  through outlet  56 , such as a tapered outlet such as a cone shaped outlet, and into a chamber  66  (in  FIG.  2   , chamber  66  is positioned behind a cover  68  and is better shown in  FIG.  3    (cover  68  is removed from  FIG.  3   )) formed in a body  64 . Granular particles  58  selectively conveyed by a distributor  74  positioned in chamber  66  and urged into driven rotational movement by a motor  76  are entrained or otherwise conveyed from chamber  66  by pressurized air  70  ( FIG.  5   ) from a pressurized air source  72  ( FIG.  5   ) such as a blower, with the particle-laden pressurized air  71  being selectively distributed by the operator (not shown) via a distribution system  78  to be discussed in additional detail below. 
     Preferably, the granular particles  58  are dry to minimize clumping together. 
     For purposes herein, the terms “granular particles”, “granular material”, and the like are intended to refer to a plurality of small, closely packed solid matter in contact with one another that is capable of being controllably distributed, discharged, or otherwise entrained for distribution by a portable pressurized air source. 
     For purposes herein, the term “portable” is intended to mean is able to be easily carried. 
     Returning now, collectively, to  FIGS.  2 - 5   , body  64  is now discussed. Body  64  includes a generally cylindrical chamber  66  such as a substantially circular cylinder formed therein for rotatably receiving a distributor  74  ( FIG.  3   ) that is selectively urged into rotational movement by a motor  76  ( FIG.  3   ) such as a DC motor powered by a power source  80  ( FIG.  3   ) such as a battery such as a lithium ion battery or other suitable battery or gasoline-powered motor for selectively controlling a flow rate of granular particles  58  ( FIG.  2   ) from outlet  56  of enclosure  50 . More specifically, chamber  66  includes passageways  82 ,  84 ,  86  extending outwardly therefrom. 
     More specifically, passageway  82  is in fluid communication with outlet  56  to receive granular particles  58  ( FIG.  2   ) by virtue of gravity from outlet  56  with distributor  74  ( FIG.  3   ) for controlling a flow rate of the granular material into the cylindrical portion of chamber  66 . Passageway  84  (which is shown more clearly in  FIG.  3    than in  FIG.  5   ) is in fluid communication with pressurized air source  72  and with an end  88  ( FIG.  3   ) of a conduit  90  ( FIG.  3   ) that extends to an opposed end  92  ( FIG.  2   ) positioned in enclosure  50  ( FIG.  2   ) such as near or proximate to an upper portion of enclosure  50  ( FIG.  2   ) such that conduit  90  ( FIG.  3   ) is in fluid communication with both pressurized air source  72  and enclosure  50  ( FIG.  2   ). As a result, even with conduit end  92  ( FIG.  2   ) being positioned in enclosure  50  ( FIG.  2   ) sufficiently distal from enclosure outlet  56  ( FIG.  2   ) so as to not result in aerating granular particles  58  proximate to the enclosure outlet  56  ( FIG.  2   ), by virtue of the enclosure being pressurized by conduit  90  ( FIG.  3   ) to a magnitude at least equal to, if not greater than the pressure magnitude at passageway  82  ( FIG.  2   ), a reverse flow of granular particles  58  at the enclosure outlet  56  ( FIG.  2   ) is preventing during operation of the spreader. Stated another way, the spreader of the present invention is designed to operate without needing to or without regard to agitating the granular particles in the enclosure in close proximity to the enclosure outlet, which in other spreader designs, may be required to operate, or at least to operate as intended. In one embodiment, conduit end  92  ( FIG.  2   ) may be positioned at a location other than an upper portion of enclosure  50  ( FIG.  2   ), although when the spreader is not operating, such alternate positioning may result in a reverse flow of granular particles  58  into conduit  90  by virtue of gravity if the conduit end is vertically positioned below the level of granular particles in the enclosure. Preferably, passageway  84  is in close proximity to pressurized air source  72 , permitting the magnitude of static pressure to be maximized. 
     In one embodiment, as shown in  FIG.  2   , at least a portion of conduit  90  is a tube extending at least partially exterior of body  64  and enclosure  50 . However, in one embodiment, such as by employing additive manufacturing (also referred to as 3D printing) conduit  90  may be at least partially formed integrally (i.e., defining or formed having one piece construction) with at least one of body  64  and enclosure  50 . 
     Returning to  FIG.  5   , passageway  86  is formed in body  64  for discharging granular material  58  ( FIG.  2   ) entrained in pressurized air  70  from pressurized air source  72 . In one embodiment, passageways  84 ,  86  are in mutual fluid communication with pressurized air source  72 . In one embodiment, it may be possible for passageways  84 ′ ( FIG.  3   ) and  86  ( FIG.  5   ) to be independent and separate from one another, while both being in fluid communication with pressurized air source  72 . In one embodiment, passageways  84 ,  86  are in direct, mutual fluid communication via chamber  66 , e.g., a direct tee-type connection between passageways  84 ,  86  and chamber  66 . 
     Returning to  FIG.  3   , distributor  74  is now discussed. As shown, distributor  74  is formed of a resilient material, and includes a center body  94  having a plurality of arms  96  such as six generally extending radially outward therefrom and generally equally angularly arranged relative to one another about the center body, each arm  96  terminating in an enlarged mass or end  98  and defining a geometric shape such as cylinder such as a ovular cylinder or a circular cylinder that is adapted to form a substantially fluid tight slidable contact with the substantially circular surface portion of chamber  66 . In other words, the outer diameter defined or traced by ends  98  is intended to be slightly greater than the diameter of the substantially circular surface of chamber  66 , such that ends  98  are maintained in sliding contact with chamber  66 . As a result, by virtue of this sliding contact including a sufficient number of arms  96  and corresponding ends  98 , and in further combination with the length of the center body and corresponding arms/ends of the distributor similarly being approximately the same, and possibly slightly greater than the depth of the chamber (the distance between cover  68  ( FIG.  3   ) and opposed wall surface  100  ( FIG.  4   ) of the chamber), distributor  74  substantially isolates passageway  82  from passageways  84 ,  86 , thereby acting to reduce pressure fluctuations associated with passageway  82  during operation of the spreader, and thereby further acting to prevent a reverse flow (i.e., backflow) of the granular material at the enclosure outlet during operation of the spreader. 
       FIG.  6    shows an schematic of an exemplary electrical circuit  102  of a material spreader of the present invention, in which power source  80  (( FIG.  3   ); e.g., a battery) provides electrical power for drivingly actuating a pressurized air source motor  73  for generating pressurized air by the pressurized air source  72  ( FIG.  3   ) for the spreader, and provides electrical power for drivingly actuating motor  76  for drivingly rotating distributor  74  ( FIG.  3   ) for providing granular particles  58  ( FIG.  2   ) to be entrained in the pressurized air  70  ( FIG.  5   ) during operation of the spreader. Electrical power from power source  80  ( FIG.  3   ) may be simultaneously selectively continued/discontinued to motors  73 ,  76  by actuation of a main power switch  104  such as a toggle switch, and electrical power from power source  80  ( FIG.  3   ) may be selectively continued/discontinued to motor  76  by actuation of a switch  106  such as a toggle switch. Alternately, electrical power from power source  80  ( FIG.  3   ) may be selectively increased/decreased for controlling the speed of motor  76  by actuation of a variable speed switch  108 . Similarly, electrical power from power source  80  ( FIG.  3   ) may be selectively increased/decreased for controlling the speed of motor  73  by actuation of a variable speed switch  110 . 
     Returning to  FIG.  2   , the spreader includes distribution system  78  adapted to distribute the granular material thereby, the distribution system  78  having a flexible portion  112  connected to a body outlet  114  at one end  116  of flexible portion  112 , with the opposite end  118  of flexible portion  112  terminating at a rigid portion  120  extending to a fitting  122  adapted to distribute the granular material from an end of the rigid portion opposite the flexible portion. In one embodiment, such as shown in  FIG.  7   , rigid portion  120  further comprises a handle  124  including a control  126  such as a trigger for controlling a flow of pressurized air from the pressurized air source such as by actuating variable speed switch  110  ( FIG.  6   ) that selectively controls the speed of motor  73  ( FIG.  6   ), and another control  128  such as a button for on/off control of the rotational speed of the distributor  74  such as by actuating switch  106  ( FIG.  6   ) such as a toggle switch (a predetermined rotational speed when on, zero rotational speed when off), controls  126 ,  128  being adapted to operate independently from one another. It is to be understood that the switch functionality could be reversed in other embodiments. Moreover, it is to be understood by those having ordinary skill in the art that the ergonomic arrangement of handle  124  including controls  126 ,  128  are adapted to be operated with a single hand. For example, in one embodiment, any combination of either of the controls  126 ,  218  may be adapted to be acutated or operated by one of the same finger, thumb or portion of the same single hand. That is, in one embodiment, one of controls  126 ,  128  is operated by one finger of the single hand, a thumb of the single hand, or a portion of the single hand, and the other of the controls  126 ,  128  is operated by the one finger or a different finger of the single hand, the thumb of the single hand, the portion of the single hand, or a different portion of the single hand. 
     Alternately, as shown in  FIG.  8   , handle  124  includes an axis  132  and further includes a single, multi-function control  130  such as a specially configured trigger  131  that is not only adapted for controlling a flow of pressurized air from the pressurized air source such as by actuating variable speed switch  110  ( FIG.  6   ) in actuation directions  134  (e.g., squeezing and releasing trigger  131 ) that selectively controls the speed of motor  73  ( FIG.  6   ), multi-function control  130  further includes additional actuation directions  136  (control 130/trigger  131  actuates in a direction parallel to axis  132 ), and/or actuation rotational directions  138  (control 130/trigger  131  rotates about axis  132  in either direction) with each respective actuation directions/rotational directions  136 ,  138  providing one or both (e.g., on/off in one direction, and variable speed in the other direction) of on/off or variable speed control of the rotational speed of the distributor  74  operating in a similar manner as previously discussed, with each of actuation directions/actuation directions/rotational directions  134 ,  136 ,  138  being adapted to operate independently from one another. It is to be understood that the switch functionality could be changed to accommodate any desired operational combination in other embodiments. 
     In one embodiment, a wand-type distributor has a flexible portion  112  ( FIG.  2   ) connected to body outlet  114  ( FIG.  2   ) and terminating at a rigid portion  120  ( FIG.  2   ) extending to a fitting  122  ( FIG.  2   ) adapted to distribute the granular material from an end of the rigid portion opposite the flexible portion. 
     It is to be understood that the various descriptions of the embodiments disclosed herein have been simplified to illustrate only those elements, features, and aspects that are relevant to a clear understanding of the disclosed embodiments, while eliminating, for purposes of clarity, other elements, features, and aspects. Persons having ordinary skill in the art, upon considering the present description of the disclosed embodiments, will recognize that other elements and/or features may be desirable in a particular implementation or application of the disclosed embodiments. However, because such other elements and/or features may be readily ascertained and implemented by persons having ordinary skill in the art upon considering the present description of the disclosed embodiments, and are therefore not necessary for a complete understanding of the disclosed embodiments, a description of such elements and/or features is not provided herein. As such, it is to be understood that the description set forth herein is merely exemplary and illustrative of the disclosed embodiments and is not intended to limit the scope of the invention as defined solely by the claims. 
     In the present disclosure, other than where otherwise indicated, all numbers expressing quantities or characteristics are to be understood as being prefaced and modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, any numerical parameters set forth in the following description may vary depending on the desired properties one seeks to obtain in the embodiments according to the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter described in the present description should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. 
     Also, any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein and any minimum numerical limitation recited herein is intended to include all higher numerical limitations subsumed therein. Accordingly, Applicant reserves the right to amend the present disclosure, including the claims, to expressly recite any sub-range subsumed within the ranges expressly recited herein. All such ranges are intended to be inherently disclosed herein such that amending to expressly recite any such sub-ranges would comply with the requirements of 35 U.S.C. .sctn.112, first paragraph, and 35 U.S.C. .sctn. 132(a). 
     The grammatical articles “one”, “a”, “an”, and “the”, as used herein, are intended to include “at least one” or “one or more”, unless otherwise indicated. Thus, the articles are used herein to refer to one or more than one (i.e., to at least one) of the grammatical objects of the article. By way of example, “a component” means one or more components, and thus, possibly, more than one component is contemplated and may be employed or used in an implementation of the described embodiments. 
     Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein, is incorporated herein in its entirety, but only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material expressly set forth in this disclosure. As such, and to the extent necessary, the express disclosure as set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein is only incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. 
     While the invention has been described with reference to one or more embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. In addition, all numerical values identified in the detailed description shall be interpreted as though the precise and approximate values are both expressly identified.