1. Field of the Invention
The present invention relates to grinders, mills or shredders used to convert a material from an unprocessed state to a processed state having a reduced particle size.
2. Description of the Related Art
Grinders, shredders or mills are well known devices for reducing the particle size of a material. For example, U.S. Pat. No. 5,192,029 to Harris and U.S. Pat. No. 5,680,994 to Eide et al. each disclose mills for grinding garbage. Each of these mills includes a rotor rotatably mounted in a generally octagonal housing. The rotor includes a generally vertical shaft and a plurality of blades or hammers mounted on the shaft. Garbage is admitted into the housing through an inlet near the top of the housing and is impacted by the blades of the rotor. Material of a reduced particle size is removed from the mill through an outlet near the bottom of the housing. The ground garbage can be sent to a landfill where it will take up less room than unprocessed garbage, or it can be composted or recycled, depending on the included materials. If the material is to be shipped, it can be shipped more efficiently due to its reduced size and greater density.
The mill of Eide et al. '994 further includes a fan or impeller which is mounted on the rotor shaft below the cutting blades. The fan is intended to create airflow which acts to move material through the mill and to expel it from the outlet. The fan generally comprises a fan disc mounted to the rotor shaft which has a plurality of radially extending lengths of angle iron mounted thereon. One flange of each angle iron is bolted to the fan disc and the other extends upwardly from the disc to act as a fan blade. The angle irons are fixedly mounted to the fan disc and no means are provided for adjusting the airflow for different materials or grinding conditions.
It should be noted that, in addition to moving material through the mill, the airflow from the fan also acts to remove moisture from the material as it is being ground. Since different materials and different grinding conditions produce different moisture levels in the material, it would be advantageous if the rate of airflow could be adjusted.
The present invention is a grinder of the general type disclosed above and including an improved fan assembly. The fan assembly includes fan blades having an additional top flange which extends generally in the direction of rotation of the fan disc. The top flanges increase efficiency by inhibiting air from flowing over the tops of the fan blades and thereby drawing more air through the system. The fan blades are adjustably mounted to the fan disc so that they can be repositioned for increasing or decreasing airflow through the grinder.
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, the words “upwardly,” “downwardly,” “rightwardly,” and “leftwardly” will refer to directions in the drawings to which reference is made. The words “inwardly” and “outwardly” will refer to directions toward and away from, respectively, the geometric center of the embodiment being described and designated parts thereof. Said terminology will include the words specifically mentioned, derivatives thereof and words of a similar import.
Referring to the drawings in more detail, the reference number 1 generally designates a grinder according to the present invention. The grinder 1 includes a rotor 3 rotatably mounted in a housing 5. The rotor 3 includes a generally vertical shaft 7 and a plurality of cutter discs 9 longitudinally mounted on the shaft 7 and extending radially outward therefrom. A fan disc 10 is connected to the shaft 7 below the lowermost of the cutter discs 9 and spaced downwardly therefrom. For example, the drawings show three cutter discs 9 denominated as discs 9a, 9b, and 9c from top to bottom, with the fan disc 10 spaced downwardly from cutter disc 9c.
Each cutter disc 9 has a plurality of cutter blades or hammers 11 connected thereto which extend radially outward past the outer edge of the respective cutter disc 9. Four hammers 11 arranged at 90 degree intervals are shown for each of the cutter discs 9. The hammers 11 are each shown as being rigidly connected to the top surface of the respective cutter disc 9 by a pair of bolts 13. It is foreseen, however, that each hammer 11 could be fastened by only a single bolt 13 so as to pivot or swing about the bolt 13 relative to the respective cutter disc 9.
The housing 5 is generally octagonal in shape and includes a sidewall 14 comprising eight sidewall sections 15, a top wall 17 and a bottom wall 19. The housing 5 includes a door 21, comprising three of the sidewall sections 15, which is hingedly connected to a main housing 23 which comprises the remaining five sidewall sections 15. The top and bottom walls 17 and 19 are each divided into respective first sections 17a and 19a which form part of the main housing 23 and respective second sections 17b and 19b which form part of the door 21. The line of division between the first sections 17a and 19a and the second sections 17b and 19b preferably extends through the axis of rotation of the shaft 7 such that the rotor 3 may be easily installed or removed through the opening provided by swinging open the door 21. An entrance chute 25 for admitting material into the grinder 1 is formed on the top wall 17 and communicates with the interior of the housing 5 through an opening in the top wall 17. A discharge chute 27 for discharging material from the grinder 1 is formed through the sidewall 14 and communicates with the interior of the housing 5 through an opening formed in the sidewall 14 just above the plane of rotation of the fan disc 10.
The shaft 7 of the rotor 3 is rotatably journaled to the main housing section 23 by upper and lower bearings 29 and 31 respectively. The upper bearing 29 is mounted in a pillow block 32 located immediately above the top wall 17 and connected to an upper framework 33 which is fixed to the top wall 17. Similarly, the lower bearing 31 is mounted in a pillow block 34 located immediately below the bottom wall 19 and connected to a lower framework 35 which is fixed to the bottom wall 19.
Each sidewall section 15 includes a sidewall framework 37 comprising a plurality of horizontal ribs 39 extending between vertical ribs 41. A respective replaceable wear plate 43 covers the interior of each sidewall framework 37. Mounted to the interior surface of each wear plate 43 are a plurality of angle deflectors 45, the number of angle deflectors 45 on each sidewall section 15 being equal in number to the number of cutter discs 9. As best seen in
The angle deflectors 45 are mounted to the respective sidewall sections 15 in such a manner that the position of each angle deflector 45 can be fine tuned to insure proper alignment with the respective cutter disc 9. Referring again to
A gap A is defined between the outer edge of each cutter disc 9 and the inner edge of the horizontal flanges 49 of the respective angle deflectors 45. The cutter discs 9a, 9b, and 9c are of somewhat increasing diameter from the top to the bottom of the grinder 1 such that the gap A decreases.
Referring to
With the fasteners 81 loose and the inner hub member 63 uncompressed, the hub 61 (and attached cutter disc 9 or fan disc 10) can be moved along the shaft 7 and repositioned anywhere within the limits of the length of the respective key 69. Once the cutter disc 9 is in the desired position, the fasteners 79 are tightened, drawing the inner hub member 63 into the tapered central bore 77 of the outer hub member 65 and compressing the inner nub member 63 against the shaft 7 to retain the hub 61 and disc 9 or 10 in position.
Referring to
The bottom flange 87 of each of the fan blade 85 has a plurality of mounting holes formed therein for receiving fasteners 95 (three shown) used to connect the fan blades 85 to the fan disc 10. The fan disc 10 has mounting holes 97 formed therein for receiving the fasteners 95. It is preferred, however, that there be extra mounting holes 97 in the disc 10 to allow the blades 85 to be selectively repositioned to adjust the airflow through the grinder 1. For example, the disc 10 is shown in the drawings as having a single mounting hole 97a proximate the outer edge of the disc 10 for the outermost of the fasteners 95. The remaining fasteners 95 are provided with multiple mounting holes 97, arranged in arcuate rows. Five mounting holes 97b are shown for the middle fastener 95, and five mounting holes 97c are shown for the innermost fastener 95. By selectively pivoting the fan blades 85 about the fastener 95 in the outermost hole 97a and selecting different pairs of the mounting holes 97b and 97c, an operator of the grinder 1 can adjust the angular orientation of the fan blades 85 relative to a true radial orientation and thereby increase or decrease the airflow through the grinder 1 to best suit specific materials to be ground and operating conditions.
The rotor 3 of the grinder 1 is driven by a motor 99 which may be, for example, an electric or hydraulic motor. The motor 99 is mounted to one of the sidewall sections 15 and includes a shaft 101 which is operably connected to a lower portion of the shaft 7 below the bottom wall 19 of the housing 5, such as by a chain and sprocket or belt and sheave system 103.
The grinder 1 may be mounted on any suitable supporting structure, including a trailer (not shown) if it is desired to make the grinder 1 portable. Suitable conveyors may be provided for moving material into the inlet 25 and away from the outlet 27.
It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown. As used in the claims, identification of an element with an indefinite article “a” or “an” or the phrase “at least one” is intended to cover any device assembly including one or more of the elements at issue. Similarly, references to first and second elements, or to a pair of elements, is not intended to limit the claims to such assemblies including only two of the elements, but rather is intended to cover two or more of the elements at issue. Only where limiting language such as “a single” or “only one” with reference to an element, is the language intended to be limited to one of the elements specified, or any other similarly limited number of elements.
Number | Name | Date | Kind |
---|---|---|---|
2160695 | Brannon | May 1939 | A |
4690338 | Sayler et al. | Sep 1987 | A |
5192029 | Harris | Mar 1993 | A |
5340036 | Riley | Aug 1994 | A |
5680994 | Eide et al. | Oct 1997 | A |
5685498 | McCoy | Nov 1997 | A |
5685500 | Eide et al. | Nov 1997 | A |
5692688 | Waitman et al. | Dec 1997 | A |
6227473 | Arnold | May 2001 | B1 |
6726133 | Hahn et al. | Apr 2004 | B2 |
6991189 | Hahn et al. | Jan 2006 | B2 |
7055769 | Pierce | Jun 2006 | B2 |
20090126608 | Borissov et al. | May 2009 | A1 |
Number | Date | Country | |
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20100327096 A1 | Dec 2010 | US |