Abstract
A sieve is disclosed for use in a plansifter. The sieve can be changed between backwire and combined sieve configurations without the height of the sieve changing, and while maintaining contact between a frame of the sieve and the sieve box. A dynamic combined cleaner also is disclosed in which the center of gravity of the cleaner dynamically changes based on inertial movements applied to the cleaner.
Claims
1. A sieve for a plansifter configured to be interchangeable between a backwire configuration and a combined configuration, the sieve comprising: a sieve box having an open top and being divided into a sieving zone and a falling zone, the sieve box including at least one aperture through at least one wall within the sieving zone and at least one ledge along an interior of at least one wall within the sieving zone; and a removable frame configured to fit within the sieving zone of the sieve box, the frame having an overhang portion configured to sit on an edge of the sieve box around the sieving zone and an extended portion configured to sit on the at least one ledge, wherein the extended portion defines a notch at a bottom of the frame configured to accept a backwire grille between the at least one ledge and the frame, with the sieve configured as the backwire sieve, without changing an overall height of the sieve.
2. The sieve of claim 1, wherein the frame via the extended portion contacts the at least one ledge of the sieve box with the sieve configured in both the backwire configuration and the combined configuration.
3. The sieve of claim 1, further comprising a bottom sheet defining a bottom of the sieving zone below the removable frame.
4. The sieve of claim 3, further comprising one or more dividers on the bottom sheet configured to partition the sieving zone of the sieve into multiple expulsion zones.
5. The sieve of claim 4, further comprising the backwire grille lying on the one or more dividers and fitted into the notch defined by the extended portion of the frame.
6. The sieve of claim 1, wherein the frame further includes one or more dividers configured to partition the frame into multiple cleaning zones.
7. The sieve of claim 1, wherein the height of the extended portion is about 8% of height of the frame, and the height of the at least one aperture is about 38% of the height of the frame.
8. The sieve of claim 7, wherein a ratio of the height of the at least one aperture to the height of the sieve box is about 1:4 with the sieve in the backwire configuration and the combined configuration.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 illustrates a backwire sieve of the related art.
(2) FIG. 2 illustrates a combined sieve of the related art.
(3) FIG. 3A illustrates a perspective view of a sieve that can be changed between a backwire configuration and a combined configuration, in accord with aspects of the present disclosure.
(4) FIG. 3B illustrates a top view of the sieve of FIG. 3A, in accord with aspects of the present disclosure.
(5) FIG. 3C illustrates a bottom view of the sieve of FIG. 3A, in accord with aspects of the present disclosure.
(6) FIG. 3D illustrates a side view of the sieve of FIG. 3A, in accord with aspects of the present disclosure.
(7) FIG. 3E illustrates an exploded view of the sieve of FIG. 3A, in accord with aspects of the present disclosure.
(8) FIG. 3F illustrates a detailed cross-sectional view of the sieve of FIG. 3A along the line 3F-3F in FIG. 3E, in accord with aspects of the present disclosure.
(9) FIG. 4A illustrates a cross-sectional view of the sieve of FIGS. 3A-3F, with dimensions, in accord with aspects of the present disclosure.
(10) FIG. 4B illustrates a cross-sectional view of the sieve of FIG. 2, with dimensions, in accord with aspects of the present disclosure.
(11) FIG. 4C illustrates a cross-sectional view of the sieve of FIG. 1, with dimensions, in accord with aspects of the present disclosure.
(12) FIG. 5A illustrates a perspective view of a dynamic combined cleaner, in accord with aspects of the present disclosure.
(13) FIG. 5B illustrates a perspective view of the dynamic combined cleaner of FIG. 5A with the cover removed, in accord with aspects of the present disclosure.
(14) FIG. 5C illustrates a top view of the dynamic combined cleaner of FIG. 5B, in accord with aspects of the present disclosure.
(15) FIG. 5D illustrates a bottom view of the dynamic combined cleaner of FIG. 5A, in accord with aspects of the present disclosure.
(16) FIG. 5E illustrates a side view of the dynamic combined cleaner of FIG. 5A, in accord with aspects of the present disclosure.
(17) FIG. 5F illustrates a cross-sectional view of the dynamic combined cleaner of FIG. 5A alone the line 5F-5F in FIG. 5C, in accord with aspects of the present disclosure.
(18) The present disclosure is susceptible to various modifications and alternative forms, and some representative embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the disclosure is not intended to be limited to the particular forms illustrated and described. Rather, the present application covers all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure, as further defined by the appended claims.
DETAILED DESCRIPTION
(19) While the concepts disclosed herein are susceptible to embodiment in many different forms, there is shown in the drawings and will herein be described in detail example implementations of the concepts with the understanding that the present disclosure is to be considered as an exemplification of the principles of the concepts and is not intended to limit the broad aspects of the disclosed implementations to the examples illustrated. For purposes of the present detailed description, the singular includes the plural and vice versa (unless specifically disclaimed); the words “and” and “or” shall be both conjunctive and disjunctive; the word “all” means “any and all”; the word “any” means “any and all”; and the word “including” means “including without limitation.”
(20) The present disclosure provides a sieve having a sieve box and a sieve frame that can be selectively configured for use in a backwire-sieve or a combined-sieve configuration, depending on which sieve type is appropriate. Further, the height of the sieve does not change between the sieve being configured as a backwire wire and as a combined sieve. Also, the contact of the frame with the sieve box remains the same for the backwire and combined configurations.
(21) FIGS. 3A-3F illustrate a sieve 300 that solves the above-addressed issues of conventional backwire and combined sieves. Specifically, FIG. 3A illustrates a perspective view of the sieve 300, in accord with aspects of the present disclosure. FIG. 3B illustrates a top view of the sieve of FIG. 3A, in accord with aspects of the present disclosure. FIG. 3C illustrates a bottom view of the sieve of FIG. 3A, in accord with aspects of the present disclosure. FIG. 3D illustrates a side view of the sieve of FIG. 3A, in accord with aspects of the present disclosure. FIG. 3E illustrates an exploded view of the sieve of FIG. 3A, including a bottom perspective view of the exploded-out frame, in accord with aspects of the present disclosure. FIG. 3F illustrates a detailed cross-sectional view of the sieve of FIG. 3A along the line 3F-3F in FIG. 3E, in accord with aspects of the present disclosure. As used herein, the terms bottom, top, and the like are in reference to views of a plansifter and its components or parts as installed relative to earth. Milled product is introduced at the top and falls through the plansifter under the force of gravity aided by the mechanical vibrational movements of the plansifter.
(22) Referring to FIG. 3A, the sieve box 302 is generally divided into a sieving zone 302a and a falling zone 302b. Side walls 302d of the sieve box 302 at the sieving zone 302a are shorter than the end walls 302e of the falling zone to accommodate the thickness of the frame 304. That is, with the frame 304 on the sieve box 302, the top of the frame 304 is flush with the walls 302e of the falling zone 302b to present a flat surface of the sieve 300 for the sieve stack. Within two of the walls 302d are openings 302c that allow particles to pass through the sieve box 302 and onto to sieves below. However, the openings 302c can be in one or more of the walls 302d.
(23) The sieve box 302 includes two ledges 302f (FIG. 3E) as shown on opposite ends of the sieve box 302. The ledges 302f support the frame 304 within the sieve box 302. As discussed above, the frame 304 includes the sieve cloth (not shown). The ledges 302f also support the backwire grille 306, when the sieve 300 is configured as a backwire sieve with the backwire grille 306 within the sieve box 302. The sieve box 302 also includes dividers 310a. The dividers 310a separate the sieving zone 302a of the sieve box 302 into the three expulsion zones 312a. The frame 304 also includes dividers 310a that separate the sieving zone 302a of the sieve box 302 into six cleaning zones 312b. Below the dividers 310a and 310b and the frame 304 within the sieving zone 302a is the bottom sheet 308 where the particles that fall through the sieve cloth collect prior to falling through the openings 302c.
(24) Referring to FIG. 3F, the bottom of the frame 304 includes an extended portion 318 that provides a peripheral zone of support and sits on the ledge 302f of the sieve box 302. The extended portion 318 allows the frame 304 to sit on the ledge 302f so that the sieve box 302 supports the frame 304 with or without the backwire grille 306 within the sieve 300. The extended portion 318 also defines a notch 320. The notch 320 accommodates the backwire grille 306 with the sieve 300 configured as a backwire sieve. Thus, the extended portion 318 and the notch 320 allows the frame 304 to work in both backwire and combined configurations, with or without the backwire grille 306, and the notch 320 allows the frame 304 to accommodate a backwire grille 306 without changing the overall height of the sieve 300 with the backwire grille 306 present versus without. The constant height allows the same number of sieves 300 to be in a sieve stack regardless of their configuration, while still providing the ability to change the sieves 300 between backwire and combined configurations, as desired.
(25) As also shown in FIG. 3F, the frame 304 includes the overhang portion 322 that sits on the top of the sieve box 302 around the sieving zone. The walls 302e of the falling zone 302b are flush with the top of the frame 304 based on the thickness of the overhang portion 322.
(26) FIGS. 4A-4C illustrate cross-sectional views of the sieves 300, 200, and 100, respectively, through walls of the sieve boxes and the frames, along with various dimensional relationships. Referring to FIG. 4A, the length L1 of the sieve 300 is the height of the sieve 300 and can vary depending on the specific requirements of the sieve 300 within a plansifter. The length L2 is the distance from the bottom sheet 308 to the top of the sieve 300. In some embodiments, the length L2 can be about 55% to about 75% of the length L1, such as about 65% of the length L1. The length L3 is the height of the frame 304. In some embodiments, the length L3 can be about 50% to about 70% of the length L2, such as about 60% of the length L2. The length L4 is the distance from the top of the backwire grille 306 (when present) to the top of the sieve 300. In some embodiments, the length L4 can be about 40% to about 60% of the length L2, such as about 50% of the length L2. The length L5 is the distance the extended portion 318 extends outward. In some embodiments, the length L5 can be about 6% to about 10% of the length L2, such as 6% or 7% or 8% or 9% or 10% of the length L2. The length L6 is the height of the opening 302c. In some embodiments, the length L6 can be about 34% to about 44% of the length L2, such as about 34% or 35% or 36% or 37% or 38% or 39% or 40% or 41% or 42% or 43% or 44% of the length L2. In some embodiments, the ratio of the length L3 to the length L6 (e.g., L3/L6) can be about 1.5:1 (e.g., 1.4:1 or 1.6:1), and the ratio of the length L1 to the length L6 (e.g., L1/L6) can be about 4:1 (e.g., 3.9:1 or 4.1:1).
(27) Referring to FIG. 4B, the length L7 of the sieve 200 is the height of the sieve 200. The length L8 is the distance from the bottom sheet 208 to the top of the sieve 200. The length L9 is the distance from the bottom of the frame 204 to the top of the sieve 200. The length L10 is the height of the opening 202c. As shown, the frame 204 does not include an extended portion.
(28) Referring to FIG. 4C, the length L11 of the sieve 100 is the height of the sieve 100. The length L12 is the distance from the bottom sheet 108 to the top of the sieve 100. The length L13 is the distance from the bottom of the frame 104 to the top of the sieve 100. The length L14 is the thickness of the backwire grille 106. The length L15 is the height of the opening 102c.
(29) According to the configuration described above for the sieve 300, the ratio L3/L6 of the height of the frame to the height of the side opening can be greater than the corresponding ratio of the sieves 200 and 100. Further, the ratio L1/L6 of the height of the sieve to the height of the side opening can be greater than the corresponding ratio of the sieves 200 and 100.
(30) As discussed above, aspects of the present disclosure also include a dynamic combined cleaner that has a dynamic center of gravity. This allows the dynamic combined cleaner to provide better contact against a sieve cloth and also not follow preferential paths within a sieve during use. Better overall cleaning coverage of the cloth is provided using the dynamic combined cleaner according to the present disclosure, and the dynamic combined cleaner according to the present disclosure also doubles as an expeller, hence the term “combined” cleaner.
(31) Although the dynamic combined cleaner is disclosed below in the context of the sieve 300, the dynamic combined cleaner can be used in any type of combined sieve, including the combine sieve of the related art, such as shown in FIG. 2.
(32) FIGS. 5A-5D illustrate a dynamic combined cleaner 550 that solves the above-addressed issues of conventional combined cleaners. Specifically, FIG. 5A illustrates a perspective view of the dynamic combined cleaner 550, in accord with aspects of the present disclosure. FIG. 5B illustrates a perspective view of the dynamic combined cleaner 550 of FIG. 5A with the cover removed, in accord with aspects of the present disclosure. FIG. 5C illustrates a top view of the dynamic combined cleaner 550 of FIG. 5A, in accord with aspects of the present disclosure. FIG. 5D illustrates a bottom view of the dynamic combined cleaner 550 of FIG. 5A, in accord with aspects of the present disclosure. FIG. 5E illustrates a side view of the dynamic combined cleaner 550 of FIG. 5A, in accord with aspects of the present disclosure. FIG. 5F illustrates a cross-sectional view of the dynamic combined cleaner 550 of FIG. 5A along the line 5F-5F in FIG. 5C, in accord with aspects of the present disclosure.
(33) As shown in FIG. 5A, the dynamic combined cleaner 550 includes a body 552, with a one side 552a configured to face the sieve cloth within the sieve 300, and one side 552b configured to face the bottom sheet 308 of the sieve 300. The side 552a of the body 552 includes multiple cleaning heads 554. The side 552b of the body 552 includes a projection or foot 556 (FIGS. 5D and E) that extends from the side 552b. Extending from side 552b of the body 552 also is an arm 558.
(34) As illustrated, the body 552 generally has the shape of a reuleaux triangle. However, the shape of the body 552 can vary without departing from the scope of the present disclosure. For example, the general shape of the body 552 can be circular, triangular, square, rectangular, pentagonal, hexagonal, etc., and various non-uniform shapes.
(35) The projection 556 is configured to rest on the bottom sheet 308 of the sieve 300 and be the furthest distal portion of the cleaner 550 from the side 552b of the body 552. The projection 556 also in part determines the height of the dynamic combined cleaner 550. Because the height (e.g., L2 in FIG. 4A) within the sieve 300 between the sieve cloth and the bottom sheet 308 can be larger than the height (e.g., L8 in FIG. 4B) in the sieve 200 depending on the overall height of the sieve 300 versus the sieve 200, the dynamic combined cleaner 550 can be taller in height than a conventional combined cleaner. The additional height allows the dynamic combined cleaner 550 to contact the sieve cloth while resting on the bottom sheet 308. For example, the dynamic combined cleaner 550 can be about 8 mm taller in height to accommodate the height difference. However, in some embodiments, the dynamic combined cleaner 550 can be taller or shorter depending on the dimensions of the sieve in which the dynamic combined cleaner 550 is to be used.
(36) The distal end 556a of the projection 556 can be various shapes, such as flat, hemispherical, elliptical, etc. When the distal end 556a of the projection 556 is other than flat, the shape can aid the cleaner 550 in being able to tilt so that the cleaning heads 554 can contact the sieve cloth.
(37) The projection 556 can be positioned generally at the center of the body 552. In one embodiment, the projection 556 can define the illustrated axis Ai, and the axis Ai can be along the center of gravity of the static portion of the cleaner 550. Alternatively, the center of gravity of the cleaner 550 can be off axis from the axis Ai, such as if the arm 558 adds additional weight to the cleaner 550 on one side.
(38) The cleaning heads 554 extend along a perimeter of the body 552. Each cleaning head 554 is configured to contact the sieve cloth above the dynamic combined cleaner 550 during use in the sieve 300 to clean clogs in the sieve cloth. In some embodiments, the cleaning heads 554 can be solid projections, as shown. Alternatively, the cleaning heads can vary, such as having one or more bristles, spikes, etc. that aid in cleaning clogs in the sieve cloth.
(39) The arm 558 projects horizontally from the body 552 of the cleaner 550 to aid in expelling particles that have fallen through the sieve cloth. Although only one arm 558 is shown, in some embodiments, the cleaner 550 can have more than one arm 558, such as one arm 558 on each vertex of the edges of the body 552.
(40) Referring to FIGS. 5B and 5F, the body 552 includes a recess 560. In some embodiments, the recess 560 can extend along substantially the perimeter of the body 552, such as a channel. The recess 560, thus, can be below the cleaning heads 554 or interior to and adjacent the cleaning heads 554. In some embodiments, the recess 560 can span substantially all of the central portion of the body 552 such that the body 552 is substantially hollow with the cover attached.
(41) Within the recess 560 are one or more weight elements 562. The weight elements 562 are enclosed within the recess 560 by a cover 568 (FIG. 5A), which also keeps particles from entering the recess 560. In some embodiments, the weight elements 562 are able to freely move within the recess 560 responsive to inertial movement of the cleaner 550 based on the mechanical movement of the sieve 300 within the sieve stack. In some embodiments, the weight elements 562 can be spherical to aid in the weight elements 562 being able to freely move within the recess 560. However, the weight elements 562 can be any size and shape that is able to freely move within the recess 560 in response to movement of the dynamic combined cleaner 550. In some embodiments, the weight elements 562 can be made of a material that has a greater density than the material the forms the body 552 of the cleaner 550. For example, the weight elements 562 can be ball bearings made of metal and the body 552 can be made of a plastic. The freely moving one or more weight elements 562 create a dynamic unbalancing effect to the cleaner 550 as it is being vibrated about the sieve 300. Not only is the cleaner 550 statically unbalanced, meaning that under static conditions (at rest), the cleaner 550 will tend to tip over and favor one side over other side(s), according to the present disclosure, a dynamic unbalancing element is introduced to move independently relative to movements of the cleaner 550 during vibration of the plansifter. These two combined effects cooperate to produce out-of-phase or poly-phasic movement or kinetic components that allow expanded movements by the cleaner 550 inside the sieve 300, covering maximal area in a consistent way without preferentially favoring too much one spot over others. Thus, the weight elements 562 are a mass in or on the cleaner 550, which can move independently of the cleaner 550 to impart a dynamic or kinetic unbalancing effect as the cleaner 550 undergoes erratic movement within a constrained volume.
(42) Based on the weight elements 562 being able freely move within the recess 560, the weight elements 562 dynamically change the center of gravity of the cleaner 550. The presence of the weight elements 562 causes the center of gravity to never be along the axis Ai, which promotes tilting of the cleaner 550 during use and cleaning of the sieve cloth. The weight elements 562 also change the center of gravity to be more sideward, which gives more instability to the cleaner 550.
(43) Although the weight elements 562 are described as being able to freely move within the recess 560, in some embodiments the weight elements 562 can be discrete elements from the body 552 that are statically and fixedly attached to the body 552 and unable to freely move. In such embodiments, the weight elements 562 provide a static unbalancing to the cleaner 550. The weight elements 562 can be attached to the body 552 by being screwed into, adhered to, soldered onto, or otherwise mechanically fastened to the body 552. The weight elements 562 can be attached to the body 552 at locations where the additional weight of the weight elements 562 further adds to the unbalancing of the cleaner 550, which in turn can further aid the cleaner 550 in cleaning and expelling.
(44) The possibility to switch the sieve type between backwire and combined allows for the use of both solutions, or hybrid solutions, for the optimization of a sifting channel. Further, the optional backwire/combined sieve with the dynamic combined cleaner provides reliable and durable cleaning of the sieve cloth, reliable throughput expulsion, and a low probability of choke. Additionally, dynamically changing the center of gravity out of the protrusion or foot axis provides for a more random movement, avoids preferential paths, and leads to an effective tapping against the cloth.
(45) While this disclosure is susceptible to various modifications and alternative forms, specific embodiments or implementations have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the disclosure is not intended to be limited to the particular forms disclosed. Rather, the disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention(s) as defined by the appended claims.
(46) Each of these embodiments, and obvious variations thereof, is contemplated as falling within the spirit and scope of the claimed invention(s), which are set forth in the following claims. Moreover, the present concepts expressly include any and all combinations and sub-combinations of the preceding elements and aspects.
