Apparatus to reduce size of material

Abstract

Apparatus to reduce size of a light, dry, fibrous material, particularly straw, with a material supply area (1), an impeller (2) and a material release area (5) for the size reduced material as well as a ring element (4), which is arranged with a distance to the impeller (2), wherein least one size reduction tool (6) is provided at the impeller (2) and/or at the ring element (4), that is provided angular shaped, particularly L-shaped, or having the shape of a polygonal, particularly ashlar-formed, hollow profile or solid profile. Splitting particularly hard, closed fibrous structures such as nodes of straw can thereby be enabled to a major portion without excessive shortening of the straw.

Claims

1. An apparatus to reduce size of a light, dry, fibrous material comprising a ring element arranged around an axis and configured to rotate about the axis, the ring element including a plurality of tool modules detachably coupled to the ring element around an inner circumference of the ring element, an impeller mounted for rotation about the axis and spaced radially inward of the ring element to form a shearing area between the ring element and the impeller, the impeller including a plurality of tool modules detachably coupled to the impeller around an outer circumference of the impeller, and identical size reduction tools detachably connected to the tool modules of the ring element and tool modules of the impeller, each of the size reduction tools (i) including a tangential leg extending primarily along a tangent plane relative to inner circumference of the ring element and the outer circumference of the impeller and facing the shearing area and (ii) a radial leg extending from the tangential leg radially away from the shearing area relative to the axis to form a L-shape, wherein each of the tangential legs is sized to have an arc length along the tangent plane that is greater than 3 (i) of the inner circumference of the ring element to which it is coupled or (ii) of the outer circumference of the impeller to which it is coupled, and wherein each of the tangential legs is sized to have an arc length along the tangent plane less than 18 (i) of the inner circumference of the ring element to which it is coupled or (ii) of the outer circumference of the impeller to which it is coupled.

2. The apparatus of claim 1, wherein each tangential leg of the size reduction tools has a length in the range of 30 mm to 80 mm.

3. The apparatus of claim 1, wherein each tangential leg of the size reduction tools includes a front edge, a back edge, and a side-face that extends between and interconnects the front edge and the back edge and faces the shearing area to form an acute angle with the tangent plane to maintain a controlled gap between the side-faces of the size reduction tools coupled to the ring element and the side-faces of the size reduction tools coupled to the impeller.

4. The apparatus of claim 3, wherein the front edge of each tangential leg extends parallel to the axis.

5. The apparatus of claim 3, wherein the front edge of each tangential leg is arranged angular to the axis.

6. The apparatus of claim 3, wherein the impeller is configured to rotate in a first direction and the ring element is configured to rotate in a second direction that is opposite the first direction to produce a relative shearing motion between the size reduction tools coupled to the ring element and the size reduction tools coupled to the impeller.

7. The apparatus of claim 6, wherein the gap between the side-faces of the size reduction tools coupled to the ring element and the side-faces of the size reduction tools coupled to the impeller increases during the shearing motion.

8. The apparatus of claim 3, wherein a radius from the axis to the back edge of the tangential leg is smaller than a radius from the axis to the front edge of the tangential leg.

9. The apparatus of claim 3, wherein the side-face of each tangential leg is formed to include rectangular notches.

10. The apparatus of claim 3, wherein the side-face of each tangential leg is formed to include polygonal saw teeth.

11. The apparatus of claim 3, wherein the side-face of each tangential leg is formed to include rounded, U-shape notches.

12. The apparatus of claim 1, wherein the impeller is configured to rotated a first speed and the ring element is configured to rotate at a second speed that is different than the first speed of the impeller.

13. The apparatus of claim 1, wherein the impeller is configured to rotate in a first direction and the ring element is configured to rotate in a second direction that is opposite the first direction to produce a relative shearing motion.

14. The apparatus of claim 1, wherein each of the tool modules includes a support, a tool unit configured to mount one of the size reduction tools, and a clamping plate configured to clamp the tool unit to the support.

15. The apparatus of claim 14, wherein the support is shaped to provide a guiding notch to locate the tool unit on the supporting means.

16. The apparatus of claim 15, wherein each of the radial legs is coupled either to the ring element or the impeller by a fastener that extends through the radial leg.

Description

(1) The invention will be described in more detail based on exemplary embodiments as shown in the FIGS. 1 to 3. It is shown in:

(2) FIG. 1: Detailed view of an apparatus to reduce size of material with a tool module and a size reduction tool at the ring element and the impeller as cross section.

(3) FIG. 2: Illustration of a size reduction tool at the impeller.

(4) FIG. 3: Illustration of a size reduction tool at the ring element.

(5) FIG. 4: Illustration of a tool module with a size reduction tool.

(6) FIG. 5a, b, c: Side-face variants of the size reduction tool.

(7) The exemplary embodiments as shown in the figures illustrate a size reduction machine for splitting straw for manufacturing OSSB panels, other panels made of long fibrous straw or shaped pieces made by the synthetic resin densified wood process such as table plates, chairs and other decorative products.

(8) The straw moves from a material supply area 1 to the impeller 2, which rotates around the axis 8 during operations (FIGS. 1 and 3). Between the impeller 2 and the ring element 4, which is arranged with a distance to the impeller 2, there is a shearing area 3, in which the straw is split or respectively reduced in size through the relative shearing motion 7 of the size reduction tool 6 of the impeller 2 and the ring element 4. The ring element 4 is either firmly installed or can also rotate around the axis 8. For achieving the relative motion, the ring element 4 can either rotate in counter direction to the impeller 2 or rotate with different speed. After the size reduction in the shearing area 3, the size reduced straw modes in a material release area 5.

(9) Depending on the required specifications of the size reduced straw, there can be arranged 1 to 50 tool modules 10 or size reduction tools 6 over the circumference of the impeller 2 and/or the ring element 4 with equal distance between each other. Preferably, 4 to 20 tool modules 10 or size reduction tools 6 are placed on the impeller and 12 to 30 tool modules 10 or size reduction tools 6 are placed on the ring element 4. By means of the distances between the tool modules 10 or the size reduction tools 6 in circumferential direction, a notably reliable removal of the size reduced material can be achieved. The diameter of the impeller 2 and/or the ring element 4 are in the range of 800 to 2000 mm depending on machine type. If the machine is bigger dimensioned and has bigger diameter, then a corresponding higher amount of tool modules 10 or size reduction tools 6 at the impeller 2 and/or ring element 4 are to be provided.

(10) The size reduction tool 6 as in the FIGS. 1, 2, 4 and 5a to 5c shows an angular shape with two legs (11, 12), of which the tangential leg 11 extends at least substantially tangentially and the radial leg 12 extends at least substantially radially. The tangential leg 11 and the radial leg 12 form a L-shape, wherein L-shape means an at least substantially 90 angle between both legs. The tangential leg 11 is facing the shearing area 3.

(11) The FIG. 2 shows an exemplary embodiment of a size reduction machine with a L-shaped size reduction tool 6, which is mounted at the impeller 2 and not part of a tool module 10.

(12) The FIG. 3 shows an exemplary embodiment of a size reduction machine with a size reduction tool 6, which is mounted at the ring element 4 and has the shape of an ashlar-formed hollow profile. A side of the polygonal profile, or the tangential leg 11 respectively, extend at least substantially tangentially to the ring element 4.

(13) The tangential leg 11 forms an acute angle with the tangent 13, wherein the angular point is formed by the shearing area 3 facing front edge 15 of the tangential leg in rotation direction or respectively the direction of the relative shearing motion.

(14) The acute angle 14 is chosen in the exemplary embodiments of the FIG. 1 (only impeller), 2, 3 and 4 in a way that the radius 17 of the front edge 15 to the axis 8 and the radius 17 of the back edge 16 to the axis 8 are equal or nearly equal. Hereby it can be achieved that a minimum gap width 9 between impeller 2 and ring element 4 during one rotation is defined by the front edge 15. If the acute angle 14 would be smaller, then the gap 9 during the relative shearing motion along the tangential leg 11 would become smaller. However, in order to be able to only break the nodes of the straw without shortening the straw any further, a nearly constant gap during the shearing over each other of the size reduction tools 6 at the impeller 2 and the ring element 4 is notably productive.

(15) In FIG. 1, the apparatus to reduce size of material provides at the impeller 2 and at the ring element 4 each at least one tool module 10 or respectively at least one size reduction tool 6. The tool modules 10 are identical in construction and arranged 180 rotated at the ring element 4 relative to the impeller 2. Herewith, the apparatus to reduce size of material can be manufactures with notably little expense. The acute angle 14 of the size reduction tool 6 at the ring element 4 correspond to the absolute value according to the acute angle 14 of the size reduction tool 6 at the impeller 2. The orientation of the acute angle 14 is however oriented in the opposite direction. The gap 13 will get thus bigger during the shearing over each other and therefore will not get reduced. The reduced production expense due to the lower amount of parts is opposed by a lower effectivity and efficiency for the spiting of nodes in the straw.

(16) The FIGS. 5a, 5b and 5c show exemplary embodiments of an apparatus to reduce size of material with a tangential leg 11, which has a side-face at the surface that faces the shearing area 3. FIG. 5a shows a saw teeth side-face. FIG. 5b shows a side-face with rounded notches with U-shape. FIG. 5c shows a side-face with rectangular hollows or notches with rectangular shape respectively. A side-face 18 can also be provided for the radial leg, which is not shown in the figures, though.

(17) The size reduction tool 6 in FIG. 5c comprises a plate shaped tangential leg 11 with a side-face 18 and a plate shaped radial leg 12, wherein tangential leg 11 and radial leg 12 are separate parts. This enables a notably high flexibility during set up the machine for special material specifications.

(18) The size reduction tools 6 as shown in the other figures are one-piece made of Ni-hard material via metal casting methods. By means of all the shown exemplary embodiments, a split rate of straw and the nodes of at least 90% can be achieved at simultaneous retention of an average straw length of at least 90 mm. The minimum gap width 9 is regularly between 4 to 16 mm, preferably between 8 to 10 mm, depending on the properties of the straw.

(19) The size reduction tool 6 as in FIG. 2 provides an exact 90 angle between both legs and is placed at the impeller 2 tilted, or rotated respectively, by the acute angle 14. The production expense for a 90 angular size reduction tool 6 is notably low. The gap width 9 can also retained nearly constant during a rotation of the impeller. However, these advantages are opposed by the fact that due to the tilt of the radial leg 12, the straw will move faster to the tangential leg 11 and sheared and size reduced for a shorter time period by means of the tangential leg 12. The consequence is a lower effectivity and efficiently of the size reduction process.

(20) The FIG. 4 shows a detailed view of the tool module 10, which connects the size reduction tool 6 with the impeller 2 or as shown in FIG. 1 with the ring element 4. Starting point is the supporting means 19 as part of the impeller 2 or of the ring element 4, which extends in parallel to the axis 8 and serves for mounting the size reduction tool 6 or the tool module respectively. The supporting means 19 provides a guiding notch 20, which extends particularly in longitudinal direction or respectively axis 8 of the supporting means 19. Thanks to the guiding notch 20, the tool module 10 can be assembled notably easily and precisely always at the same radial position at the supporting means 19 or respectively the impeller 2 or ring element 4.

(21) A tool unit 21 of the tool module 10 as a protrusion for generating a form fit with the guiding notch 20 of the supporting means 19, wherein the protrusion is designed in a way that motion in longitudinal direction of the guiding notch 20 is possible. The tool unit 21 further provides a drill hole, in which a screw can be inserted in order to connect the size reduction tool 6 with the tool unit 21 in a force-fit manner. The size reduction tool 6 therefore also provides a drill hole, namely in form of a particularly radial oriented oblong hole 22. By means of the oblong hole 22, the radial position of the size reduction tool 6 can be notably easily and flexibly adjusted. In a further embodiment, which is not shown, the size reduction tool 6 provides a drill hole and the tool unit 21 has the oblong hole.

(22) A clamping plate 23 connects the tool unit 21 with connected size reduction tool 6 to the supporting means 19 by means of a screw connection.

(23) Therefore, a force-fit and form-fit connection is obtained, which is notably easily detachable.

(24) By means of the tool unit 21 of the tool module 10 it can be achieved that an adjustment of the minimum gap width 9 can be conducted not at the impeller 2 or ring element 4, but notably efficient and with little effort at a separated adjustment station, which is not shown in the figures.

(25) Preferably, the screw connection between size reduction tool 6 and tool unit 21 is chosen in a way that the head of the screw is arranged at the side of the size reduction tool 6 and has such a big circumference that at any adjustment, the oblong hole is covered by the head of the screw. Contamination of the oblong hole through entering materials can thus notably reliably be avoided.

(26) In particular, a light, dry, fibrous material comprises reed, respectively cane.

(27) In particular, a light, dry, fibrous material comprises haulms, strands or fibers from sweet grass such as rice or rice straw, corn, wheat, barley, millet, oat, rye or cattail.

(28) In particular, a light, dry, fibrous material comprises jute, cannabis, flax, kenaf, palm frond or sisal.

(29) In particular, a light, dry, fibrous material comprises coco, soybean, bamboo, peanut shells, light weight wood, cotton, respectively cotton plant or wool.

(30) In particular, a light dry, fibrous material comprises textile waste, vegetable waste, paper waste or other light, dry fibrous waste products.

(31) In particular, with the expression straw in the above description and the claims are also meant other lignocellulosic materials with straw-like structure such as reed and rice straw.