Fine comminutor

Abstract

A comminution device comprises a plurality of first cutting elements having first serrated cutting edges disposed on a first circular path; a second cutting element having a second serrated cutting edge corresponding to the first serrated cutting edges for cutting through cutting material, the second cutting element being displaceable about an axis of rotation on a second circular path concentric with the first circular path. The second serrated cutting edge comprises a plurality of jags and each jag comprises a radially inner flank and a radially outer flank, each at an angle to the axis of rotation. A drive rotationally drives the second cutting element about the axis of rotation and an adjustment mechanism by which the plurality of first cutting elements and the second cutting element are displaceable relative to each other axially in the direction of the axis of rotation, that a cutting gap between them is adjustable.

Claims

1. A comminution device, comprising: a plurality of first cutting elements having first serrated cutting edges disposed on a first circular path; and at least one second cutting element having a second serrated cutting edge corresponding to the first serrated cutting edges for cutting through a cutting material, the second cutting element being displaceable about a rotational axis on a second circular path concentric with the first circular path, the second serrated cutting edge comprising a plurality of jags and each jag comprising a radially inner flank and a radially outer flank, each of the radially inner flank and the radially outer flank at an angle to the axis of rotation; a drive for rotationally driving the second cutting element about the axis of rotation; and a first adjustment mechanism by which an axial position of the plurality of first cutting elements relative an axial position of the second cutting element is axially adjusted in the direction of the axis of rotation such that a first cutting gap between the first cutting elements and the second cutting element is adjustable; wherein the radially outer flanks of the plurality of jags are longer than the radially inner flanks of said jags.

2. The comminution device according to claim 1, wherein the jags are disposed on a path running at an angle to the axis of rotation.

3. The comminution device according to claim 1, wherein the angle to the axis of rotation of the outer flanks and the angle to the axis of rotation of the inner flanks are different.

4. The comminution device according to claim 2, wherein the angle to the axis of rotation of the outer flanks of at least some of the plurality of jags is greater than the angle to the axis of rotation of the inner flank.

5. The comminution device according to claim 1, wherein the angle to the axis of rotation of the radially outer flank of at least one radially outer jag is greater than the angle to the axis of rotation of the radially outer flank of a radially inner jag.

6. The comminution device according to claim 5, wherein the angle to the axis of rotation of the radially outer flanks of the radially outer jags is respectively greater than the angle to the axis of rotation of the radially outer flanks of the radially inner jags.

7. The comminution device according to claim 1, wherein the second cutting element is mounted on an axially displaceable hub, and wherein an axial position of the hub is adjustable and releasably fixed within the comminution device.

8. The comminution device according to claim 7, wherein the device comprises a first screw for defining the axial position of the hub and a lock screw for fixing the axial position.

9. The comminution device according to claim 1, further comprising a plurality of third cutting elements having third serrated cutting edges disposed on a third circular path.

10. The comminution device according to claim 9, wherein the third circular path is concentric with the first circular path and has the same diameter.

11. The comminution device according to claim 9, wherein the second cutting element comprises a fourth serrated cutting edge corresponding to the third serrated cutting edges for cutting through the cutting material.

12. The comminution device according to claim 11, wherein the second cutting edge and the fourth cutting edge are implemented substantially mirror-symmetrical.

13. The comminution device according to claim 3, wherein an axial position of the plurality of third cutting elements relative the axial position of the second cutting element is axially adjusted in the direction of the axis of rotation by a second adjustment mechanism, such that a second cutting gap between them is adjustable.

14. The comminution device according to claim 13, wherein the third cutting elements are mounted in a housing, and wherein an axial position of the housing is adjustable and releasably fixed within the comminution device.

15. The comminution device according to claim 14, wherein the device for determining the axial position of the housing comprises a first screw for defining an axial position of the housing and a lock screw for fixing the axial position of the housing.

16. The comminution device according to claim 1, further comprising a pre-comminutor disposed upstream of the first and second cutting elements and comprising: a first pre-cutting element comprising at least one first pre-cutting edge; and a second pre-cutting element displaceable on a second pre-cutting element circular path relative to the first pre-cutting element, the second pre-cutting element comprising at least one second precut edge; wherein the second pre-cutting element is coupled to the drive for rotationally driving the second cutting element.

17. The comminution device according to claim 1, wherein the at least one second cutting element is disposed at an angle to the axis of rotation.

18. The comminution device according to claim 17, wherein the at least one second cutting element encloses an angle with the axis of rotation in a range of >0° to 90°.

19. The comminution device according to claim 18, wherein the at least one second cutting element encloses an angle with the axis of rotation in a range of >0° to 45°.

20. The comminution device according to claim 19, wherein the at least one second cutting element encloses an angle with the axis of rotation in a range of 5° to 45°.

21. The comminution device according to claim 17, wherein the second cutting element is mounted on a hub, wherein the hub comprises at least one radial recess having a mounting surface disposed at an angle to the axis of rotation, wherein the second cutting element is mounted on the mounting surface.

22. The comminution device according to claim 1, wherein the at least one second cutting element comprises a passage for reducing a flow resistance.

23. A comminution device, comprising: a plurality of first cutting elements having first serrated cutting edges disposed on a first circular path; and a second cutting element having a second serrated cutting edge corresponding to the first serrated cutting edges for cutting through a cutting material, the second cutting element being displaceable about a rotational axis on a second circular path concentric with the first circular path, the second serrated cutting edge comprising a plurality of jags and each jag comprising a radially inner flank and a radially outer flank, each of the radially inner flank and the radially outer flank at an angle to the axis of rotation; a plurality of third cutting elements having third serrated cutting edges disposed on a third circular path, wherein the third circular path is concentric with the first circular path and has the same diameter; a fourth serrated cutting edge disposed on the second cutting element and corresponding to the third serrated cutting edges; a drive for rotationally driving the second cutting element about the axis of rotation; and a first adjustment mechanism by which an axial position of the plurality of first cutting elements relative an axial position of the second cutting element is axially adjusted in the direction of the axis of rotation such that a first cutting gap between the first cutting elements and the second cutting element is adjustable, and a second adjustment mechanism by which an axial position of the plurality of third cutting elements relative an axial position of the second cutting element is axially adjusted in the direction of the axis of rotation such that a second cutting gap between the third cutting elements and the second cutting element is adjustable.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, the invention is explained in more detail using two embodiment examples with reference to the associated figures. Shown are:

(2) FIG. 1 is a section through a comminution device according to a first embodiment example in an installed state;

(3) FIG. 2 is the detail Z of FIG. 1;

(4) FIG. 3 is a section through the comminution device;

(5) FIG. 4 is a detailed view of a second cutting element;

(6) FIG. 5 is the section B-B according to FIG. 6;

(7) FIG. 6 is a plan view with partial breakout on the device according to FIG. 1;

(8) FIG. 7 is a comminution device in the installed state according to a second embodiment example;

(9) FIG. 8 is a perspective view of a hub together with second cutting elements of a comminution device according to a third embodiment example; and

(10) FIG. 9 is a side view of the hub of FIG. 8.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(11) A comminution device 1 is disposed in a pot 2 of a pipe system. The pot 2 comprises an inlet 4 and an outlet 6, which can be flanged to corresponding tubes. Inside, the pot 2 comprises a separating plate 8 that separates inlet 4 and outlet 6 from each other. A passage 10 is implemented in the separating plate 8, in which passage the comminution device 1 is inserted. The comminution device 1 is described in more detail with reference to the further figures. It comprises a main housing 12, in which a drive shaft 14 is supported, which is coupled to a drive 16. The entire comminution device 1 is pivotally mounted on the pot 2 via a pivoting mechanism 18 and can be pivoted away from the pot 2 about a pivot point 20 with reference to FIG. 1. This is used to perform maintenance on the comminution device 1 and the pot 2, for example, in the event that individual parts are jammed there.

(12) The comminution device 1 (see FIG. 2) comprises a cutting unit 22, in which a plurality of first cutting elements 24, at least one second cutting element 26 and, according to this embodiment, a plurality of third cutting elements 28 interact. In a lower segment, annularly surrounded by the third cutting elements 28, the cutting unit 22 comprises a circular inlet opening 30 through which material to be cut can enter the cutting unit 22. After the material has passed through the cutting unit, it can radially exit through gaps 32 (only one provided with reference numerals in FIG. 2) between the plurality of first cutting elements 24 and the plurality of third cutting elements 28. The flow path of the material is shown in FIG. 2 by the dashed arrow P. The material thus flows in through the inlet 4, then slightly upwards through the opening 30 into the cutting unit 22, exits there radially, passes thus comminuted behind the separating plate 8 and can flow out of the outlet 6. The slight upward flow of the material also has the task of separating off solid components not to be cut, such as stones and the like. These fall down and can then be removed from the bottom of the pot 2.

(13) With reference to FIGS. 3, 4, and 5, the cutting mechanism and the adjustment mechanism are now described in greater detail.

(14) The drive 16 is disposed on the main housing 12. The drive shaft 14 is attached rotationally fixed to the drive 16 or an output shaft of the drive 16 (not shown in detail). On the one hand, a central screw 32 is provided for this purpose, and a feather key 34 to transmit rotational forces. The drive shaft 14 is supported by means of a bearing 36 on the main housing 12.

(15) The plurality of first cutting elements 24 is initially attached on the front side against the main housing 12. A further screw connection 38 is provided for this purpose. The plurality of first cutting elements 24 is integrally implemented as a whole and the individual cutting edges 40 are milled out of a body, so that the cutting elements 24 comprise a common housing segment 42 and can be attached as a unit to the main housing 12. The cutting elements 24 are disposed on a circular path and each aligned with its main plane radially to the axis of rotation A. The central axis of the circular path is identical to the axis of rotation A.

(16) A second cutting element 26 is provided corresponding to the first serrated cutting edge 40 of the first cutting elements 24. Overall, seven second cutting elements 26 are provided according to these embodiment examples, even though only one is provided with reference numeral 26. The second cutting element 26 comprises a second cutting edge 44 which is implemented serrated and corresponds to the first cutting edge 40. The second cutting element 26 is attached to a hub 48 via a clamping connection 46. The hub 48 is, in turn, supported axially on the shaft 14, wherein a feather key 50 is provided for the torque transmission. The hub 48 is axially relocatable in the direction of the axis of rotation A and thus a distance between a shaft shoulder 52 of the drive shaft 14 and an end face 54 of the hub 48 is provided. As is readily apparent from FIG. 3, it is possible to further push the hub 48 upwardly with respect to FIG. 3 so that the end face 54 comes into contact with the shoulder 52.

(17) In the position of the hub 48 shown in FIG. 3, the cutting edges 40, 44 are aligned so that they substantially abut and form a cutting gap, which is only a few tenths of a millimetre. If there is wear on the cutting edges 40, 44, it may be necessary for an adjustment to be made. It is also conceivable that the cutting gap should be increased in order to provide a coarser comminution. For this purpose, the comminution device 1 according to the present invention comprises a first adjustment mechanism 60, which is now described.

(18) The first adjustment mechanism 60 according to this embodiment first comprises the relocatable hub 48 which carries the second cutting element or elements 26. To adjust the axial position of the hub 48, a first screw 62 is provided according to this embodiment, which screw extends through a corresponding threaded hole 64 in the hub 48. As can be seen in FIG. 3, the foot of the screw 62 extends out to a certain extent from the end face 54 of the hub 48 and is in contact with the shaft shoulder 52. Likewise, the head of the screw 62 does not lie on the annular shoulder of the threaded hole 64, but has a certain distance therefrom. By the extent of the excess length of the screw foot from the end face 54, the distance of the end face 54 can thus be adjusted to the shaft shoulder 52 and thus defined. To fix this position, a lock screw 66 is provided which braces a cover 68 against the hub 48 and the drive shaft 14 and thus defines the hub 48. Although only a first screw 62 and a lock screw 66 are shown in FIG. 3, it should be understood that a plurality of such screws can be provided around the circumference of the hub 48 and the cover 68 to achieve uniform tensioning.

(19) According to this embodiment (FIG. 3), it is further provided that the cutting unit 22 comprises a plurality of third cutting elements 28, which are formed substantially identically to the first cutting elements 24. Said cutting elements also comprise serrated cutting edges 70. The third cutting elements 28 are optional, but lead to a higher rate of comminution. The third cutting elements 28 according to this embodiment example correspond with a fourth cutting edge 72 of the second cutting element 26. The third cutting elements 28 are milled from a material and thus comprise a common housing 74. The inlet 30 is also defined through the housing 74.

(20) The third cutting elements 28 are attached to the housing 42 of the first cutting elements 24 via the housing 74. The distance between the third cutting edges 70 and fourth cutting edges 72 is adjustable by means of a second adjustment mechanism 60′. For this purpose, threaded holes 76 are provided on the housing 74 (see FIG. 5), which have a similar principle as the threaded holes 64 of the screw 62. A screw 78 is inserted in the threaded hole 76, which screw is supported with its foot end against a stop 80 on the housing 42 of the first cutting elements 24. An outer diameter of the third cutting elements 28 is slightly smaller than an inner diameter of a segment 82 of the first cutting elements 24, so that the housing part 74 with the third cutting elements 28 can dip into the first housing part 42 with the first cutting elements 24. To guide the housing 74 during the axial adjustment by means of the screw 78, a guide tab 84 is provided, which engages in a recess 86. A further screw 88 is provided for determining and fixing the axial position, which screw engages in a threaded hole 90 on the housing 42 and so brace the two housing parts 72, 74 against each other and load the screw 78 on pressure.

(21) A single second cutting element 26 is shown in FIG. 4, on which the geometry of said jags 100 can be seen. Only one jag 100 is provided with reference numerals in FIG. 4, but the other jags are also implemented. The jag 100 comprises two flanks 102, 104, wherein 102 refers to the radially inner flank, while 104 refers to the radially outer flank. The radially inner flank 102 encloses an angle α with the axis of rotation A or an axis A′ running parallel thereto. A corresponding angle β encloses the flank 104 with the axis A′. The radially outer flanks 104 are longer than the radially inner flanks 102, so that the jags 100 are disposed in total on a path B, which is at an angle to the axis of rotation. In this embodiment example, based on a plane E perpendicular to the axis of rotation A, an angle γ is delineated approximately in the range of 30°.

(22) The angle β of jags 100, which lie radially further outward, that is, with respect to FIG. 4 further right, is greater than the angle β of jags which lie radially further inward, that is, further left in FIG. 4. This has the effect that the flanks 104 of jags which lie radially further outward is flatter than of jags 100 which lie radially further inward. If now an axial distance between the second cutting elements 26 and the first cutting elements 24 is reduced, the distance between the flanks 104 which lie radially further outward, and the corresponding counter flanks at the cutting edges 40 becomes disproportionately smaller than the distance between the flanks 104, which lie radially further inward and the corresponding counter flanks, both seen as normal distance to the flank surface. This makes it possible to compensate for the higher wear on jags 100 lying radially further outward when a wear adjustment is made and an axial adjustment is performed for this purpose.

(23) A second embodiment example of the comminution device 1 is shown in FIG. 7. The same parts are provided with the same reference numerals, and to that extent, reference is made in full to the above description of the first embodiment example (see FIGS. 1-6).

(24) In contrast to the first embodiment example (see, in particular, FIG. 2), the comminution device 1 according to this embodiment comprises a pre-comminutor 120. The pre-comminutor 120 comprises a first pre-cutting element 122 and a second pre-cutting element 124. The first pre-cutting element 122 is implemented as a perforated disc and mounted in front of the inlet opening 30. The second pre-cutting element 124 is a blade holder having a total of four blades 125a, 125b disposed thereon (only two blades can be seen in FIG. 7). The blade holder is connected via a shaft extension 126 to the drive shaft 14, so that the blade holder rotates together with the drive shaft 14, the hub 48 and thus also the at least one second cutting element 26. The pre-cutting element 122 is preferably implemented in accordance with the perforated disc from EP 2 613 884, and the second pre-cutting element 124 is preferably implemented like the blade holder from EP 2 613 884 B1. The edges of the holes of the perforated disc together with the blades 125a, 125b of the blade holder form corresponding cutting and material to be cut through can be separated thereon by rotation of the blade holder. Such a product is already known from the market and is sold by the patent proprietor under the name “RotaCut.”

(25) FIGS. 8 and 9 illustrate a third embodiment example. More specifically, in FIGS. 8 and 9, only the hub 48 and the second cutting elements 26 are shown. The remaining elements of the comminution device 1 are identical to the first two embodiment examples, so that they are not shown here for reasons of clarity. The unit shown in FIGS. 8 and 9 can, therefore, also be used in the comminution devices 1 of the first two embodiment examples (FIGS. 1-7).

(26) The hub 48 comprises a plurality of radial recesses 130 which define a mounting surface 132. The respective second cutting elements 26 are mounted as said mounting surfaces 132. This is achieved in this third embodiment example by two screws 134, 136 each, which extend through corresponding through holes (not shown) on the second cutting elements 26 and are screwed on the hub 48 in internally threaded provided blind holes (not shown). As an alternative to said screw connection, other connections are conceivable and preferred, in particular, clamping and/or plug connections.

(27) The second cutting elements 26 are all disposed at an angle with respect to the axis of rotation A. While the cutting elements 26 in the first embodiment examples lay together in a plane with the axis of rotation A or at least parallel thereto, they enclose an angle γ in this embodiment example (FIGS. 8 and 9). The angle γ is measured between a plane E defined by the plate-shaped second cutting elements and the axis of rotation A. The angle γ in the present embodiment example is approximately 45° (see FIG. 9). It can, however, also have a different value, which is preferably in a range of >0° to 90°. The individual cutting jags 100 are in turn preferably at an angle and indeed at a complementary angle ε (see FIG. 9), so that the cutting jags are aligned generally perpendicular to the axis of rotation A. This facilitates effective cutting. The inclination of the cutting jags 100 is best seen from the second cutting element 26, which is shown in the middle in FIG. 9 and on the basis of which the angles are plotted.

(28) A further difference in this embodiment example lies in that the second cutting elements each comprise a passage 140. The passages 140 are basically implemented so that they are approximately adapted to the outer contour of the second cutting elements 26, but allow a sufficient wall thickness both for attaching the second cutting elements 26 to the hub 48, as well as a cutting. Different geometries are conceivable here in order to allow an efficient fluid flow, or even to positively influence said flow by the specific geometry of the passages 140. It should be understood that the passages 140 can also be provided at the second cutting elements 26 of the first two embodiment examples (FIGS. 1-7) and are only albeit optionally preferred in the third embodiment example (FIGS. 8 and 9).