1. Field of the Invention
A rotary grinding mill that increases the effectiveness of the grinding process and the collection process, while minimizing the noise and vibration generated by the grinding mill and provide a compact storage configuration.
2. Background
The invention relates to a grinding mill. A grinding mill is the process of applying a mechanical force to a grain to overcome the interior bonding forces of the grain. The mechanical force causes the grain to break into smaller pieces. Grinding food serves several purposes such as increasing the flavor, the texture, and nutritional value of the food.
The concept of grinding or milling food particles dates to prehistoric man. Currently, there are several different types of grinding mills available. One very popular type of grinding mill is a rotary mill that comprises two grinding discs contained within a housing unit. Generally, there is a stationary grinding disc that has radially spaced concentric rows of blades extending from the face of the disc. A second rapidly rotational grinding disc that also has radially spaced concentric rows of blades extending from the face of the rotating grinding disc. The blades from the stationary grinding disc, and the blades from the rotating grinding disc are oriented in such that the concentric rows of blades of the rotation disc are disposed between the concentric rows of blades of the stationary disc thereby provide alternating rows of radially spaced blades.
Rotary mills have several limitations. One such limitation is the excess noise and vibration. The noise and vibration are generally created by the motor, the movement of the grinding disc, and the sounds of the material being milled. In addition, rotary mills are very bulky and cumbersome to store. Another problem is the poor results from the grinding method. Generally, users prefer the grain to be uniformly and finely ground. When food particles have not reached the desired size, the users may be required to send the food products through the mill several times before achieving the correct results. Lastly, the milling process creates an excessive amounts of fine particles which are exhausted into the air. All these limitations have caused users to stop using rotary mills.
Several prior inventions have made attempt to overcome these limitations. In Scott, U.S. Pat. No. 4,422,578 attempted to resolve the limitation of particles suspended in the air. Scott provided an exhaust device that created a helical movement of the air. In addition, Scott added a foam filter. However, the helical movement of the air as taught in Scott was not effective and the foam filter becomes quickly clogged. Also, Scott did not even attempt to eliminate the other limitations of rotary mills.
Scott-Black, U.S. Pat. No. 5,660,339 attempted to improve the quality of the grinding mill by controlling the amount of grain fed to the milling disc. Scott-Black showed a method for controlling the volume of grain fed into the milling discs. Scott-Black included a feed tube which a user could adjust to control the flow of grain. However, the feed tub was separate from the control switches, and requires the mill to create vibration to allow the grain to feed through the tube. Scott-Black did included a collection system that used a revised helical movement of air and a foam filter to separate particles from the discharged air. While the Scott-Black invention did remove more particles than Scott, it is still not effective enough to prevent the foam filter become clogged frequently. Thus, requiring the foam filter to be removed and cleaned excessively. Scott-Black failed to teach anything that would address the limitation of noise, vibrations, or storage. In Scott-Black, the mill actually describes a method to create an unbalance milling disc to create vibrations. The additional vibration resulted in additional noise. Scott-Black also added a collection container, thus adding to the limitation of minimizing the area required to store the mill.
Although the prior art did attempt to minimize the described limitations, the prior art did not resolve the limitation adequately. In spite of the previous efforts, there remains a need for a rotary mill that improves the grinding process that creates a uniform, finely milled grain, that limits the noise and vibration, decreases the air particles discharged, and is minimizes the area required to store the mill.
It is a principal object of the invention to provide a rotary grinding mill that improves the grinding process, creating a uniform finely ground material by increasing the effectiveness of the rotary grinding process. Allowing the user to easily control the amount of grain feeding into the rotary milled grain. Another object is to provide a collection container that receives the air and ground material and effectively filters particles out of the air. Another advantage is to provide a rotary mill that limits the noise and vibration by allowing an easier way to balance the grinding discs and by controlling the air flow through the mill that includes several noise buffers. In accordance with another aspect of the invention, is to provide a means to limit the area required to store the mill by combining the mill into a single enclosed unit.
The invention may take form in certain parts and arrangement of parts, and preferred embodiment of which will be described in detail in the specification and illustrated in the accompany drawing, which for a part hereof:
The following discussion describes embodiments of the invention and several variations of these embodiments. This discussion should not be construed, however, as limiting the invention to these particular embodiments. Practitioners skilled in the art will recognize numerous other embodiments as well. It is not necessary that the grinding mill have all the features described below with regard to the specific embodiments of the invention shown in the figures.
In the flowing description of the invention, certain terminology is used for the purpose of reference only, and is not intended to be limiting. Terms such as “upper”, “lower”, “above”, and “below,” refer to directions in the drawings to which reference is made. Terms such as “inward” and “outward” refer to directions towards and away from, respectively, the geometric center of the component described. Terms such as “side”, “top”, “bottom,” “horizontal,” and “vertical,” describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology includes words specifically mentioned above, derivatives thereof, and words of similar import.
Referring to
As seen in
Unless otherwise noted, the remaining description will assume that the mill 2 is in the operational configuration. As described above, the hopper 6 stores the grain or food products. As shown in
As shown in
Located inside the mill housing 3 is a pressure switch 32. When the valve 30 is in the off position, the switch arm 36 applies a force to the pressure switch 32. As described above, when the dial 9 is rotated, the valve 30 rotates. As the valve 30 rotates, the switch arm 36 releases the pressure from the pressure switch 32 allowing power to the motor 16.
The mill assembly 22 comprises a stationary grinding disc 102 and a rotational grinding disc 104. The stationary grinding disc 102 is sometime referred to as a stator, and is attached to the mill housing 3. The rotational grinding disc 16 is attached to the motor 12 by means of a shaft 20. The shaft 20 is positioned in a shaft port 14 located in the center of the rotational grinding disc 16. The motor 12 is attached to the mill housing 3. The rotational grinding disc 104 will spin at speeds between 10,000 to 35,000 rotations per minute. The rotational speed and torque of the motor 12 is such as to create sufficient torque that is required to mill the grain. The mill assembly 22 is generally constructed out of steel or other higher strength material that can withstand the high speeds and forces exerted during operation.
Both the stationary grinding disc 102 and rotational grinding disc 104 have a plurality of grinding blades 112. The stationary grinding disc 102 has radially spaced concentric rows of blades 112 extending therefrom in a first axial direction. The rotational grinding disc 104 has radially spaced concentric rows of blades 112 extending therefrom in a second opposing axial direction. The blades 112 on the rotational grinding disc 104 and the blades 112 on the stationary grinding disc 102 are oriented in a confronting axial alignment such that at least some of the concentric rows of blades of the rotational grinding disc 104 are disposed between the concentric rows of blades of the stationary graining disc 102 thereby provide alternating rows of radially spaced blades 112.
The blades 112 have a face edge 120 and a rear face 124. The face edge 120 of each blade row is non-perpendicular to the radius of the milling assembly. The angle of the face edge 120 is between 45 to 89 degrees, creating a cutting edge 126 similar to a knife blade. The cutting edge 126 allows the grain to be cut instead of sheared.
As shown in
As shown in
Proper balancing of the rotational grinding disc 104 is crucial to reducing both noise and vibration. Traditionally, the rotational grinding disc 104 is balanced by drilling out material located on the rotational grinding disc 104. However, this drilling results in weak spots. As shown in
The blades 112 have a proximal end 27 and a distal end 28. The proximal end 27 is generally the front half the blade 112 containing the portion of the blade 112 that strikes the grain and the face edge 120. The distal end 27 is generally the back half end of the blade and located on the opposite end of the longitude axis of the blade 112 from the proximal end. One skilled in the art will recognized that the dividing line between the proximal end and the distal end 28 may vary and not necessarily the center of the blade 112. The outer most concentric row of blades 112 on the rotational grading disc 104 the a proximal end 27 of the blades 112 are angled from the longitude axis of the blade 26. As shown in
The discharge port 58 connects to a discharge conduit 50. The connection between the discharge port 58 and discharge conduit 50 forms an airtight seal, but is releasable by the user. As shown in
As illustrated in
To increase the cyclonic flow pattern 60, the container lid 56 has an incline 58 as shown in
As shown in
The air and any remaining particles enters the first cyclone air filter 58. The air circulates around the first cyclone filter 58 in the cyclonic flow pattern 60. While flowing in a cyclonic flow pattern 60, the fine particles drop from the airflow and particles are stored in the base of the cyclone air filter 58. The air and any remaining grain particles travel from the first cyclone filter 58 through an air channel 49. The second cyclone filter 59 uses the same cyclonic flow pattern 60 described above for the first cyclone filter 58.
The virtually particle free air is then discharged through an air discharge outlet 50 located on the container lid 56. To ensure that the air is clean, a foam filter 54 is located in the discharge port 58. A filter plug 64 is inserted in the center of the foam filter 58, forcing the air to travel at an angle through the foam filter 54, therefore increasing the length the air must travel through the foam filter 54.
The finished milled grain is then fully captured in the collection container 4. The milled grained may be stored in the collection container 4. A bag 75 may be placed inside the storage container 4 to collect the milled grain and which allows the user to easily removed the mill grain from the collection container 4. The bag is held in place by a bag ring 74 located along the circumference of the in the collection container 4.
The mill 2 requires a constant airflow to operate. The milling process and operation of the motor creates heat. Excess heat may damage the motor and the mill 2. In addition, the heat may damage the nutritional value, the taste and damage the texture of the grain. However, the motor 16 and milling assembly 22 are both a significant source of noise. Unlike the prior art, the current invention controls the flow of air through the mill housing 3 to dampen the noise. As shown in
The air is then drawn around the mill assembly 22 and around the motor 16 cooling the mill assembly 22 and the motor 16. Located directly below the fan 70, is a second air chamber 76. Similar to the first air chamber 72, the second air chamber 76 has several sound baffles 74. The air flows to a third air chamber 78. The third air chamber 78 also contains several sound baffles 3. The airflow is discharges from the mill housing 3 through air vents 79 located on the base of the mill housing 3.
While a preferred embodiment of the invention of the grinding mill has been shown and described herein, it should, however, be understood that the description above contains many specificities that should not be construed as limiting the scope of the invention. Thus, the scope of the embodiment should be determined by the appended claims and their legal equivalents thereof, rather than by the examples given.