Device and method for comminuting bulk material grains

Abstract

A device for comminuting bulk material grains (K) having a first element, designed as a rotor having a cylindrical circumferential surface with a first surface (31) and a first receiving portion (41), and a second element designed as a shear strip (51) having a second surface (61) and a second receiving portion (71), and a supply unit. The first and the second surfaces (31, 61) lie parallel to and face one another. The first and second elements are relatively movable between first and second positions (P1, P2) in a plane of the first and the second surfaces (31, 61). In the first position (P1), the first and second receiving portion (41, 71) communicate with one another, via a passage (9) forming a receptacle, in which the bulk material grain (K) can be positioned, and, upon moving to the second position (P2), a cross section of the passage (9) is narrowed.

Claims

1. A device for comminuting bulk material grains, comprising: a first element having a first surface and a first receiving section, a second element with a second surface and a second receiving section, a feeding device, wherein the first surface and the second surface are arranged parallel and facing each other, the first element and the second element are movable back and forth, relative to one another, between a first position and a second position, and the direction of movement being in a plane defined by the first and second surfaces, in the first position, the first receiving section and the second receiving section communicate with each other, via a passage, and form a receiving area in which a grain of bulk material can be positioned via the feed device, when the first element and the second element are moved from the first position to the second position, a cross-section of the passage is narrowed, wherein the first element is formed as a rotor rotatably mounted about a rotor axis and having a cylindrical circumferential surface, the first receiving section is an at least partiallyformed circumferential groove, and the rotor has at least one axial groove crossing the circumferential groove, and the first surface is a side wall of the axial groove, and the second element is designed as a shear bar and is arranged in the axial groove so as to be movable back and forth along the axial groove, and the second receiving section being a recess of the shear bar; and wherein the shear bar is movable by means of a cam gear from the first position into the second position and/or from the second position into the first position, the cam a direction of rotation of the rotor at an axial end of the rotor, upon rotation of the rotor the control cam moves an axial end of the shear bar axially, the device further comprising at least one punch axially guided in a guide bore of the rotor, the punch being connected to at least one shear bar and being moved axially by the control cam upon rotation of the rotor.

2. The device according to claim 1, further comprising a housing with a housing wall which coaxially surrounds the rotor at least in sections and has at least one feed opening and at least one outlet opening for the bulk material grains.

3. The device according to claim 2, wherein the housing wall has at least one movable housing wall section which radially overlaps the first receiving section with respect to the rotor axis.

4. The device according to claim 3, wherein the at least one movable housing wall portion cooperates with a movement sensor for detecting a movement of the movable housing wall portion.

5. The device according to claim 1, wherein the rotor axis is arranged vertically.

6. The device according to claim 1, wherein the circumferential groove is a groove extending circumferentially.

7. The device according to claim 1, wherein the axial groove extends over the entire height of the rotor.

8. The device according to claim 1, wherein the circumferential groove and the recess have a trapezoidal profile in a radial section through the rotor.

9. The device according to claim 8, wherein the circumferential groove and the recess have the profile of an isosceles trapezoid, the shorter base area of the trapezoid being arranged parallel to the rotor axis.

10. The device according to claim 1, wherein the rotor has a plurality of circumferential grooves.

11. The device according to claim 10, wherein the shear bar comprises a plurality of recesses, and in the first position each recess is associated with a circumferential groove.

12. The device according to claim 11, wherein a recess associated with a first circumferential groove in the first position is associated with a second circumferential groove in the second position.

13. The device according to claim 1, wherein the rotor comprises a plurality of shear bars, each of which is arranged in an axial groove.

14. A method for processing bulk grains, comprising the following steps: comminuting of bulk material grains with a device according to claim 1; further processing of the comminuted bulk material grains or storage of the comminuted bulk material grains; wherein no separation step is carried out between the comminution step and the further processing/storage step and in particular in that no feeding back of the comminuted bulk material grains to a device for comminuting bulk material takes place.

Description

(1) The invention is described in detail below by means of preferred examples in connection with the figures. It is shown:

(2) FIG. 1 a schematic, perspective illustration of a first embodiment of the invention;

(3) FIG. 2 schematic, perspective illustration of a second embodiment of the invention;

(4) FIG. 3 a perspective view of a further development of the device of the invention with closed housing;

(5) FIG. 4 the device of FIG. 3 with open housing;

(6) FIG. 5A a schematic illustration of the rotor of FIG. 4 in the first position;

(7) FIG. 5B a schematic illustration of the rotor of FIG. 4 when moving from the first position to the second position;

(8) FIG. 6 a schematic view of the inlet and outlet openings of the device of FIG. 4;

(9) FIG. 7A A schematic illustration of how the shear bar works in the first position;

(10) FIG. 7B a schematic diagram of how the shear bar works when moving from the first position to the second position;

(11) FIG. 8A A perspective view of a control cam with punches for axial movement of the shear bars;

(12) FIG. 8B a partial sectional view of the control cam with punches;

(13) FIG. 9 a sectional view through the housing wall with movable housing wall sections; and

(14) FIG. 10 a sectional view through the housing wall with movable housing wall sections and motion sensor.

(15) FIG. 1 schematically shows a possible design of the device according to the invention.

(16) The device 1 comprises a first element 2 and a second element 5, each with a through-bore, which form a first and a second receiving section 4 and 7 respectively for a bulk grain K. The receiving sections 4 and 7 thus form a receiving area for the bulk grain K. The through-bore 7 is shown dashed, as it is covered by the first element 2. Furthermore, the first and second elements 2 and 5 each have a flat surface 3 and 6 respectively, which are arranged parallel to each other. The through-bores 4 and 7 are aligned. A passage 9 connects the first through-bore 4 and the second through-bore 7.

(17) When moving the first element 2 and/or the second element 5 along the direction of movement M from the first position P1 shown in FIG. 1, a cross-section of the passage 9 is reduced and the bulk grain is comminuted by shearing. The comminuted bulk grain K can then be removed from the device 1 through the through-bore 4 and/or 7.

(18) The first element 2 and the second element 5 are moved back and forth between the first position P1 and a second, not shown, position P2 by means of a drive. The direction of movement M is in the plane of the first surface 3 and the second surface 6.

(19) FIG. 2 shows an alternative embodiment of the device 1 in the first position P1.

(20) In contrast to the device 1 of FIG. 1, however, the receiving sections 4 and 7 are designed as recesses of the respective element 2 and 5.

(21) Also in this case, by moving the first element 2 and/or the second element 5 along the direction of movement M from the first position P1 shown in FIG. 2, a cross-section of the passage 9 can be reduced and the bulk grain can be comminuted by shearing.

(22) FIG. 3 shows a device 1 in accordance with the invention for comminuting bulk material grains. The device 1 comprises a housing 11, which has an inlet opening 8 and an outlet opening 12 for the bulk material grains K.

(23) In FIG. 4, the housing 11 is opened so that the internal structure of the device 1 is visible. The device 1 comprises a rotor 21 with a cylindrical circumferential surface, which is schematically shown in FIGS. 5A and 5B. The rotor 21 is rotatably mounted around a rotor axis A by means of bearings 13. A motor unit 14 comprising a motor and a gear serves as rotor drive.

(24) In FIGS. 5A and 5B, the rotor 21 is shown schematically. The rotor 21 has a plurality of circumferential grooves 41, 41′ on its circumferential surface, only two of which are shown, which are designed to receive the bulk material grains K. Each circumferential groove 41, 41′ has a width B and a depth T extending in the radial direction of rotor 21 (which is shown in FIG. 7A).

(25) Rotor 21 also has a plurality of shear bars 51, 51′, of which only shear bar 51 is shown in FIGS. 5A and 5B. The shear bar 51 is located in an axial groove 10 of rotor 21 and is movable along a direction of movement M. The axial groove 10 crosses the circumferential groove 41 (and 41′). The rotor thus has a plurality of axial grooves, although FIGS. 5A and 5B show only one axial groove 10, for reasons of simplicity.

(26) It can be seen that the functioning of the device corresponds to that of the device in FIG. 2. In this case, the first location section is formed as a circumferential groove 41 and the first surface 3 corresponds to a side wall 31 of the axial groove 10.

(27) The shear strip 51 thus corresponds to the second element 5, whereby the second receiving section 7 is designed as recess 71 of the shear strip 51. One side surface 61 of the shearing strip 51, which is adjacent to the side wall 31 of the axial groove 10, therefore corresponds to the second surface 6 of the second element 5. Circumferential groove 41 and recess 71 have an identical cross-section in radial section through rotor 21 and are aligned in the first position P1 of FIG. 5A.

(28) When operating the device 1, the bulk material grains K are fed via the feed opening 8 to the rotating rotor 21, where they enter the circumferential grooves 41, 41′ and are carried along by the rotation of the rotor 21.

(29) One end of the shear bars 51, 51′ interacts with a cam disc 15, which is located at a front end of the rotor 21. As the rotor 21 rotates, the shear bars 51, 51′ are thus moved between a first position P1 (shown in FIG. 5A) and a second position P2, not shown. The resulting reduction in the cross-section of a transition 9 between the respective circumferential grooves 41, 41′ and the recess 71, 71′ of shear bar 51 in the area of the intersection between the circumferential grooves 41, 41′ and axial grooves 10, 10′ has the effect of breaking up the bulk material grains K.

(30) The comminuting is shown in FIG. 5B. If the width B of the circumferential groove 41, 41′ corresponds to the width of the shearing bar 51, it can thus be guaranteed that the size distribution of the comminuted bulk material grains K is at most B.

(31) After cutting the bulk material grains are removed from the circumferential groove 41, 41′ and leave the device 1 through the outlet opening 12.

(32) FIG. 6 shows separately a detail of the feed and discharge device of device 1. The inlet 8 and outlet 12 are connected by a conduit to corresponding inlet openings 80 and outlet openings 120 of a housing wall 16. According to a preferred embodiment, between 4 and 8 inlet openings 80 and outlet openings 120 are arranged around the circumference of the rotor 21, whereas only one inlet opening 80 and one outlet opening 120 are shown in FIG. 6. The inlet opening 80 is provided with a grid 17. On the side facing away from the rotor 21 a hopper 18 is arranged, which is filled with bulk grains when operating the device 1, so that it can be ensured that bulk grains can be fed to the rotor 21 over the entire height. The grid 17 supports the formation of a column of bulk material grain in the storage hopper 18 and ensures that not too many bulk material grains reach the rotor 21, which could lead to malfunctions of the device 1.

(33) Viewed in the rotational direction R of the rotor 21, which is shown schematically by the arrow, the inlet opening 80 is followed by an outlet opening 120. A comb device 19 is attached to the housing wall 16. The comb device 19 has a plurality of fingers 20, each of which is assigned to a circumferential groove 41, 41′ of the device. The fingers 20 protrude into the respective circumferential groove 41, 41′ and cause the comminuted bulk material grains to be removed from the circulating groove 41, 41′ and to be able to leave the device 1 for further processing through the exit opening 120.

(34) FIGS. 7A and 7B schematically show the function of cam disk 15 as a possible drive for the shear bars 51, 51′. The shear bar 51 is shown in simplified form with only one recess 71. The cam disk 15 comprises a circumferential groove 22, which is designed to face the rotor axis A. At the lower end of the shear bar 51 a projection 23 is formed, which is accommodated in the circumferential groove 22. When the rotor 21 is turned, the shear bar 51 is turned as well, while the cam disk 15 is firmly connected to the device 1. The circumferential groove 22 is designed such that during rotation, the shear bar 51 moves axially between the first position P1 of FIG. 7A and a second position P2. FIG. 7B shows an intermediate position between the first position P1 of FIG. 7A and the second position P2, the circumferential groove 41 of rotor 21 being shown as a dotted line. It should be noted that the cross-section of the passage 9 of the shear bar 51 of FIGS. 7A and 7B is trapezoidal with a depth T.

(35) FIGS. 8A and 8B show a further embodiment of the drive of the shear bars 51, 51′. The shear bars 51, 51′ etc. are connected to a holder 29 in a tension and compression-resistant manner. The holder 29 is in turn connected to a punch 27 in a tension and compression-resistant manner. The punches 27 and 27′ etc. (of which only two are provided with a reference sign, for the sake of clarity) are guided axially with respect to the axis of rotation A of the rotor 21 in an assigned guide bore 30 or 30′ of the rotor 21. A spiral spring 28 surrounds the respective punch 27, 27′ etc. and is supported at one of its ends on the rotor 21 and at the other end on the respective punch 27.

(36) In the area of the axial end S of rotor 21, several control cams 26 are arranged, of which only one is visible in FIGS. 8A and 8B. Control cam 26 is mounted non-rotatably in relation to a direction of rotation of the rotor 21, so that it does not remain stationary when rotor 21 is turning, is designed as a circular control wheel and is mounted such that it can rotate freely about axis Z—i.e. without any drive.

(37) As the rotor 21 rotates, an upper lenticular head 32 of the punch 27 comes into contact with the outer surface 33 of the control cam 26, and the punch 27 is first pressed down until it reaches the apex of the outer surface 33, the direction of movement of the punch 27 being substantially parallel to the axis of rotation A of the rotor 21. The control cam 26 is simultaneously rotated by friction around the axis Z.

(38) The movement of the punch 27 moves the shear bars 51, 51′ etc. from the first position P1 to the second position P2. Punch 27 is moved against a spring force of the spiral spring 28. The spiral spring 28 is thus compressed.

(39) The spring force of the spiral spring 28 pushes the punch 27 upwards. By further rotation of the rotor 21 and the course of the outer surface 33, the punch 27 is moved upwards again until the holder 29 experiences a stroke against a stop surface of the rotor 21. The shear bars 51, 51′ etc. thus return from the second position P2 to the starting position, which corresponds to the first position P1.

(40) In order to increase the throughput capacity of the device 1, several control cams 26 are provided, corresponding to the examples described above, which control the shear bars 51, 51′ etc. between the respective input opening 80 and output opening 120.

(41) In FIG. 9 an axial sectional view of the rotor 21 is partly shown. The housing wall 16 comprises a plurality of housing wall segments 24, which are each assigned to a circumferential groove 41 of rotor 21 and are arranged next to each other in the axial direction of the rotor 21. For the sake of clarity, only one housing wall segment 24 is provided with a reference sign.

(42) Each housing wall section 24 is preloaded by a spiral spring 34 in the direction of the rotor 21.

(43) As explained above, the trapezoidal profile of the circumferential groove 41 and the recess 71 causes the bulk material grains K to be pressed against the housing wall 16 when the shear bar 51 is moved.

(44) The pre-loading force of the spiral spring 34 is selected such that the housing wall sections 24 are not displaced when the shear bar 51 is moved. However, if a foreign body, which is hard and therefore cannot be comminuted by the device 1, enters the circumferential groove 41 and the recess 71, the trapezoidal profile causes the foreign body to be pressed against the associated housing wall section 24 and displaces it outwards in the radial direction of the rotor 21. This substantially prevents damage to the rotor 21 and in particular to the circumferential groove 41 or the recess 71 of the shear bar 51.

(45) FIG. 10 shows a preferred further development of the housing wall 16. The housing wall 16 comprises a plurality of movable housing wall sections 24, which are designed analogously to the housing wall sections 24 in FIG. 9. The device 1 additionally comprises a motion sensor 25, which comprises a flexible line 35, which is arranged radially with respect to the axis of rotation A outside the housing wall 16, directly behind the housing wall sections 24. The flexible line 35 runs parallel to the axis of rotation A of the rotor 21 and is filled with a liquid up to a set level.

(46) A level sensor, not shown, monitors the liquid level. The flexible line 35 is arranged in such a way that it is squeezed if a section of the housing wall 24 is moved outwards, causing the liquid level to rise. The level sensor determines the deviation of the liquid level from the set level. It can thus be detected whether one or more housing wall sections 24 have been shifted and thus that objects are contained in the device 1 which cannot be comminuted.