Patent Application
20060124788
The present invention relates to a particle crushing and sizing apparatus for sizing into a predetermined particle size various wet or dry materials such as drugs, foodstuffs, fodders, chemicals, fertilizers, powdered coals, limestone, and ceramics materials which are granulated or formed by various apparatuses. More particularly, the present invention relates to a particle crushing and sizing apparatus for crushing wet aggregates or dry blocks, i.e., granulated materials (lumps) granulated or formed by various apparatuses and having particle size equal to or greater than a target value, and for sizing the crushed materials into a certain particle size range.
Particle mixing, granulating and sizing operations are widely employed in numerous industrial fields, such as in the pharmaceutical and food industries. The control of particle size is an important unit operation for improving particle handling, particle quality, fluidization during fluidized drying, etc.
Thus far, conventional particle crushing and sizing apparatuses regulate particle size using screens. Herein, screens wear off and break down as a result of continued use. Also, worn off powder or broken chips from the screens may contaminate the product particles. In order to avert the above, a strict quality control management is required involving frequent screen checks.
These apparatuses have also problems in that, in the case of wet materials, the screen mesh can become clogged with the processed material, depending on its nature, as it becomes undesirably kneaded in the screen. Also, the impact force of the granulating blades may crush particle having the right size, resulting in an excess of fine powder and thus lower yields.
Therefore, the inventors of the present application developed a particle crushing and sizing apparatus using no screens (Japanese Unexamined Patent Application Publication No. 2000-117131).
The particle crushing and sizing apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2000-117131 is a particle crushing and sizing apparatus for sizing, through a predetermined holding region, wet or dry material granulated or formed by various devices and supplied from a material input port, the apparatus comprising a casing, a rotation body, an opposed face portion opposed to the rotation body at a predetermined distance, and a gap region defined by the rotation body and the opposed face portion which are provided within the casing, the gap region comprising a particle size adjusting region which allows particles suited to the gap setting to pass but does not allow particles not suited to the gap setting to pass, wherein the particles not allowed to pass through the gap region are brought into contact with the opposed face portion in association with rotation of the rotation body at an inlet or face sections of the gap region and are crushed to such an extent that the particles can pass through the gap region and discharged from a discharge port.
Herein, the gap region is composed of the face or the line sections for setting the space between the rotation body and the opposed face portion as the narrowest gap, and the particles are crushed in the narrowest gap or in the vicinity thereof.
Specifically, the rotation body is formed into a substantially conical shape, the casing is formed into a substantially hollow conical shape, the particle holding region is constituted by a casing inner wall and the rotation body, and the narrowest gap is constituted by the lower end peripheral edge of the rotation body and the inner wall of the casing.
However, in the particle crushing and sizing apparatus with the above constitution, the narrowest gap formed by the lower end peripheral edge of the rotation body, formed into a substantially conical shape, and the inner wall of the casing, formed into a substantially hollow conical shape, has a linear shape in the form of a circumference, for which reason the crushing and sizing range is relatively restricted.
Enlarging the lower diameter of the rotating body can broaden the above crushing and sizing range, but at the cost of a larger apparatus size.
Thus, an object of the present invention is to provide a particle crushing and sizing apparatus having a sufficiently large crushing and sizing range.
In order to solve the above problems, the present invention provides a particle crushing and sizing apparatus, comprising in a casing: a drive shaft provided horizontally; a plurality of circular plates fixedly supported at intervals by the drive shaft; and stators provided below the circular plates and opposing the peripheral edge plate faces of the circular plates, the stators having inclined faces such that the gap between the stators and the plate faces of the circular plates becomes narrower towards the peripheral edge of the plate faces of the circular plates; wherein the plate faces of the circular plates and the inclined faces of the stators form gap portions where particles are held, and wherein the narrowest gap portions between the peripheral edges of the circular plates and the stators form crushing and sizing portions.
In the present invention, the particles fed into the casing fall to the gap portions formed between the respective plate faces of the circular plates and the inclined faces of the stators, and only the particles allowed by the narrowest gap portions to pass through traverse these narrowest gap portions and are discharged downwards. The particles not allowed by the narrowest gap portions to pass through remain in the gap portions and are crushed by the rotation of the circular plates until they attain the target particle size.
Crushing and sizing are carried out specifically by the peripheral edges of the circular plates, in the lower portion thereof, with a view to increasing crushing and sizing efficiency and affording a more compact apparatus.
In the present invention, the stators may have preferably inclined faces opposing the plate faces of the respective neighboring circular plates.
Since both particle holding regions and narrowest gap portions can be formed on both faces of the circular plates, the number of apparatus components in the present invention may be smaller, which redounds to the compactness of the apparatus as a whole.
In the present invention, planar regions parallel to the plate faces of the circular plates may be formed on the peripheral edges of the inclined faces of the stators.
The invention allows thereby forming gaps parallel to the crushing and sizing portions, which enhances particle crushing and sizing taking place in these portions.
In the present invention, cutaway portions may be formed on the peripheral edges of the stators, with adapters provided in the cutaway portions so as to form planar regions parallel to the plate faces of the circular plates.
The invention allows thereby adjusting the gaps of the crushing and sizing portions by adjusting the thickness of the adapters.
In the present invention, the adapters may be provided in the cutaway portions of the stators via interposed spacers.
The invention allows thereby adjusting the gaps of the crushing and sizing portions by arbitrarily modifying the thickness of the spacers.
In the present invention, protrusions may be provided on the opposing faces of the circular plates and the stators that form the crushing and sizing portions.
The invention allows thereby crushing efficiently the materials to be processed, whether dry block materials wholly hard or having a hard core, by the action of the protrusions, thus enhancing the particle crushing and sizing effect in the crushing and sizing portions.
Herein, from the viewpoint of crushing and sizing efficiency, the protrusions provided on the respective opposing faces are preferably arranged so that the protrusions provided on one face may pass between the protrusions provided on the other face.
In the present invention, auxiliary pins may be provided on the plate faces of the circular plates forming the gap portions where the particles are held.
Thus, in the present invention, the auxiliary pins provided on the plate faces of the circular plates expel the particles towards the crushing and sizing portions, preventing thereby the particles from lingering behind and increasing thus processing throughput.
Herein, from the viewpoint of the expelling effect on the particles, the auxiliary pins provided on the plate faces of the circular plates have preferably a substantially triangular shape in a plan view, with one of the triangle's vertices pointing towards the rotation direction of the circular plates.
In the present invention, crushing pins for particle coarse crushing may be provided on the inclined faces of the stators and/or the plate faces of the circular plates.
Thus, even when the particles linger between the plate faces, etc. of the circular plates, the crushing pins of the invention perform a coarse crushing of the particles, thereby supplementing the crushing and sizing action taking place in the crushing and sizing portions, etc.
In the present invention, a fixed shaft may be provided spanning the interior of the casing, such that the stators are fitted to the fixed shaft via spacers, while the circular plates may be supported, via spacers, by the drive shaft.
Thereby, the gaps of the crushing and sizing portions in the present invention can be adjusted by modifying the length of the spacers of the drive shaft and the length of the spacers of the fixed shaft.
In the present invention, a particle feeding inlet may be formed in the upper central portion of the casing, with a particle dispersing means provided between the particle feeding inlet and the circular plates.
Thereby, the particles fed into the casing are distributed uniformly to the gap portions formed between the plate faces of the circular plates and the inclined faces of the stators, which allows increasing the crushing and sizing efficiencies.
In the present invention, the particle dispersing means may be constituted by arranging a cone with its tip pointing upward, in the center of the casing.
In this simple constitution, the particles fed into the casing fall along the inclined surface of the cone and are distributed among the circular plates at positions removed from the casing center, thereby distributing uniformly the particles in the gap portions formed between the plate faces of the circular plates and the inclined faces of the stators.
In the present invention, the particle dispersing means may comprise a plurality of elongated members spanning the casing in the horizontal direction.
In this simple constitution, the particles fed into the casing hit against the elongated members in succession and are dispersed thereby, thus distributing uniformly the particles in the gap portions formed between the plate faces of the circular plates and the inclined faces of the stators.
The particle crushing and sizing apparatus according to the present invention is described in detail below by way of embodiments, with reference made to relevant accompanying drawings.
The particle crushing and sizing apparatus 1 according to the present invention illustrated in
Inside the casing body 1a are also provided a plurality of stators 5 of semi-circular shape having an isosceles triangle cross-section, the apexes whereof face the drive shaft 2, and through which is inserted a fixed shaft 7 disposed spanning the casing body 1a. The stators 5 are equidistantly separated by spacers 6. As shown in
Further, as shown in
The particle crushing and sizing apparatus 1 with the above constitution has thus semi-circular stators 5, 5 and adapters 8, 8 arranged on the lower side of the circular plates so as to encompass the peripheral edge of the latter. As shown in
In this particle crushing and sizing apparatus 1, a particle feeding casing 1b is connected to the upper portion of the casing body 1a, as shown in
Inside the particle feeding casing 1b there is provided a particle dispersing means, as illustrated in
In the casing 1b shown in FIGS. 4 (a) and (b) there is provided a particle dispersing means 16 that comprises a conical dispersing member 14 with a tip 14a facing upward, and stays 15 across the plane-view center of the casing 1b.
In the particle crushing and sizing apparatus 1 having this particle dispersing means 16, the particles fed into the casing 1b fall along the inclined surface of the dispersing member 14 and are distributed among the circular plates 10, 10 at positions removed from the casing center, thereby distributing uniformly the particles in the gap portions A formed between the plate faces 10a of the circular plates 10 and the inclined faces 5b of the stators 5, 5.
In the casing 1b illustrated in FIGS. 5(a) and 5(b), there is provided a dispersing means 17 comprising a plurality (10 in this embodiment) of elongated members 17a, having a triangular cross-section, arranged equidistantly forming a triangular array pointing upwards and spanning across mutually opposing side walls of the casing 1b.
In the particle crushing and sizing apparatus 1 having this particle dispersing means 17, the particles fed into the casing 1b hit against the elongated members 17a, 17a in succession, and are dispersed thereby, thus distributing uniformly the particles in the gap portions A formed between the plate faces 10a of the circular plates 10 and the inclined faces 5b of the stators 5.
In the casing 1b illustrated in FIGS. 6(a) and 6(b) there is provided a dispersing means 18 comprising an elongated member 18a having a triangular cross-section in an uppermost tier and, below the elongated member 18a, a plurality (21 in this embodiment) of elongated members 18b having a circular cross-section, disposed in a plurality (3 in this embodiment) of tiers with the number of members per tier increasing towards the bottom; herein, all the above elongated members arranged diametrically across mutually opposing side-walls of the casing 1b.
In the particle crushing and sizing apparatus 1 having this particle dispersing means 18, the particles fed into the casing 1b hit first the elongated member 18a and next the elongated members 18b in succession, and are dispersed thereby, thus distributing uniformly the particles in the gap portions A formed between the plate faces 10a of the circular plates 10 and the inclined faces 5b of the stators 5.
In the particle crushing and sizing apparatus 1 with the above constitutions, a motor etc. rotates the drive shaft 2, which in turn rotates the circular plates 10 fixed thereto. Thus, particles such as wet aggregates, dry block materials, etc. granulated or formed by various apparatuses are fed through the particle feeding casing 1b.
The fed particles are first dispersed by the particle dispersing means 16, 17 or 18 provided in the particle feeding casing 1b, and are homogeneously distributed thereby between the circular plates 10, 10.
The distributed particles fall between the circular plates 10, 10 into the gap portions A, where particles smaller than a predetermined size travel on along the crushing and sizing portions B and are discharged through a particle discharge casing 1c. Particles larger than a predetermined size remain in the gap portions A and, by the rotation of the circular plates 10, are crushed between the plate faces 10a of the circular plates 10 and the inclined faces 5b of the stators 5 down to a predetermined size, after which they traverse the crushing and sizing portions B and are discharged through the particle discharge casing 1c.
The gaps (narrowest gap portions) in the above crushing and sizing portions B are arbitrarily set in accordance with the targeted maximum particle diameter of the particles to be processed, and their size ranges ordinarily from about 1.5 to 3 times the targeted maximum particle diameter of the particles to be processed.
The gaps (narrowest gap portions) in the above crushing and sizing portions B can be adjusted by varying the thickness of the above adapters 8. Specifically, given a ready-made assortment of adapters, replacing for instance thick adapters 8 by thinner adapters 8 allows the gap of the crushing and sizing portions B to become narrower. Replacing the circular plates 10 with other circular plates having thicker peripheral edges allows also narrowing the gaps of the crushing and sizing portions B. In the above embodiments, the gaps of the crushing and sizing portions B can also be adjusted by modifying the length of the spacers 11 fitted to the drive shaft 2 and of the spacers 6 fitted to the fixed shaft 7. Specifically, replacing the above with shorter spacers 11, 6 allows narrowing the gaps of the crushing and sizing portions B, whereas replacing them with longer spacers 11, 6, conversely, allows widening the gaps of the crushing and sizing portions B.
In the above embodiment, the adapters 8 are mounted on the cutaway portions 5a of the stators 5 in a way that the crushing and sizing portions B are formed parallel to the plate faces 10a of the circular plates 10; however, the adapters 8 may also be integrated with the stators 5 forming a single unit.
Crushing efficiency can be further increased if a plurality of crushing pins 19 for particle coarse-crushing is provided on the inclined faces 5b of the stators 5 and the opposing plate faces 10a of the circular plates 10, as shown in
Also, if the faces of the outermost edges of the circular plates 10 and the opposing faces of the adapters 8 are formed as uneven faces with protrusions, grooves, etc., crushing and sizing ability improves, while particles can be diverted more smoothly towards the discharge side, or, conversely, be confined in the gap portions A, etc., all of which can result in a more precise crushing/sizing.
Embodiments of such a particle crushing and sizing apparatus with protrusions, etc. formed on the faces of the outermost edges of the circular plates 10 and the opposing faces of the adapters 8 are described in detail below with reference to
In
In the particle crushing and sizing apparatus 1 according to this embodiment, as illustrated in
On the faces of the adapters 8 that oppose the above plate faces in the outermost peripheral edges of the circular plates 10 is formed also a plurality of spike-shaped protrusions 21. As illustrated in
The particles, for instance dry block materials wholly hard or having a hard core, that are fed into the particle feeding casing 1b and pass through the gap portions A formed between the plate faces 10a of the circular plates 10 and the inclined faces 5b of the stators 5, to reach the crushing and sizing portions B, are effectively crushed and sized by the protrusions 20, 21 having the above constitution and formed on the opposing faces of the circular plates 10 and the adapters 8 making up the crushing and sizing portions B. The particles are then discharged through the particle discharge casing 1c, without lingering in the crushing and sizing portions B.
In particular, a circular plate 10 with a 26 cm diameter has for instance 36 protrusions 20 formed in each row around its outermost peripheral edge, each of the protrusions 20 about 11 mm long in the circumferential direction, 2 mm wide in the radial direction, and 1 mm high, separated from one another by about 11 mm (equivalent to 5 degrees intervals) in the circumferential direction, with neighboring protrusions 20 in the two rows standing 4 mm apart. The two rows of protrusions 20, 20 are arranged at identical locations (in parallel) in the circumferential direction, without position shift.
The dimensions of the above protrusions 21 formed on the opposing faces of the adapters 8 are substantially the same as those of the protrusions 20, although the shape of the protrusions 21, viewed from above, may also be designed so as to block the flow of particles passing between the protrusions 20 and 21 (for instance, a substantially parallelogram shape oblique to a direction obstructing the passage of the particles).
The shape and dimensions of the above protrusions 20, 21, are obviously not limited to those described above, and may be set arbitrarily, so long as the protrusions are provided respectively on the circular plates 10 and the opposing faces of the adapters 8; if, for instance, one of the faces is flat, short pass may occur, which impairs crushing and sizing.
If the protrusions 20, 21 are formed as described above, the narrowest gap in the above crushing and sizing portions B formed between the outermost edges of the circular plates 10 and the opposing faces of the adapters 8 is then the distance between the tips of the protrusions formed on one of the above opposing faces and the other opposing face. This narrowest gap distance can be arbitrarily set as required by the target maximum particle diameter (the average particle diameter depends not only on this narrowest gap distance but also on other factors, such as circular plate rotation speed, amount of particles fed, etc.).
In the present embodiment, in particular, the narrowest gap distance can be adjusted by changing the thickness of the adapters 8 mounted on the cutaway portions 5a, leaving the thickness of the circular plates 10 unchanged.
Also, as shown in
However, setting the above narrowest gap distance to 0.5 mm or less is undesirable as it precludes the presence of the protrusions 20, 21 and may also become dangerous when the circular plates 10 rotate at high speeds.
In FIGS. 7 and others, the reference numeral 19 denotes the above-mentioned crushing pins for particle coarse-crushing when, for instance, the fed material is a dry material; as illustrated in
Specifically, there are three of the above crushing pins 19 mounted on both plate faces 10a of the circular plates 10, as illustrated in
In FIGS. 7 and others, the reference numeral 22 denotes auxiliary pins mounted on both plate faces 10a of the circular plates 10 at the positions of the gap portions A, the holding regions of the particles. The function of these auxiliary pins 22 is to expel the particles arriving to the holding regions of the gap portions A, on account of the gravity and the centrifugal force brought about by the rotation of the circular plates 10, quickly towards the crushing and sizing portions B, without lingering in the gap portions A.
The auxiliary pins 22 may have an arbitrary shape, for instance circular, rectangular, triangular, etc. viewed from above, and their mounting angle may also be set arbitrarily so as to ensure the expelling action on the particles. If their shape is triangular as viewed from above, the auxiliary pins 22 are preferably mounted with one of the triangle's vertices towards the rotation direction of the circular plates 10.
In the particle crushing and sizing apparatus 1 according to the present invention having the constitution described above, particles such as wet aggregates, dry block materials, etc. granulated or formed by various apparatuses are fed through the particle feeding casing 1b, and with the circular plates 10 rotating, are first coarsely crushed by the crushing pins 19. The centrifugal force resulting from the rotation of the circular plates 10 and the action of the auxiliary pins 22 exert then a pushing force on the particles arriving to the holding regions of the gap portions A that drives them quickly towards the crushing and sizing portions B, without lingering in the gap portions A.
Among the particles pushed into the crushing and sizing portions B, conforming particles are allowed to get through, whereas nonconforming particles, whether dry block materials wholly hard or having a hard core, are effectively crushed and sized by the protrusions 20, 21 provided on the crushing and sizing portions B and, without lingering in the crushing and sizing portions B, are then discharged through the particle discharge casing 1c, where they are recovered in a product recovery container not shown in the figures.
While the particle crushing and sizing apparatus according to the present invention has been described by way of the preferred embodiments above, it is to be distinctly understood that the invention is not limited thereto. From the foregoing description, moreover, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined in the appended claims.
For instance, in the above embodiments, the particle processing method described focuses on the apparatus according to the present invention used as a single entity; however, the apparatus according to the present invention may be used as a part of a processing plant, with discharge outlets of various types of granulating or forming equipment connected to the particle feeding casing 1b of the apparatus according to the present invention, and with feeding inlets of various equipment connected to the discharge casing 1c of the apparatus according to the present invention.
The particle crushing and sizing apparatus according to the present invention is a compact and high throughput apparatus that can be optimally used for sizing particles to a predetermined particle size for any kind of wet or dry materials granulated or formed using various equipment, such as drugs, foodstuffs, fodders, chemicals, fertilizers, powdered coal, limestone, ceramics, etc.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-86292 | Mar 2003 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP04/04231 | 3/25/2004 | WO | 10/6/2005 |
