EP2185287B1 - Vibratory grinding mill - Google Patents

Abstract

The invention relates to a vibratory grinding mill (1), in particular a vibratory disk mill, with a grinding unit (2), wherein the grinding unit (2) has a lowerable grinding base (5) and a discharge base (12), and wherein, furthermore, the discharge base (12) has an all-round discharge channel (24), for delivering the grinding material to a and/or through a discharge element (25), and, in respect of advantageous development, proposes that the discharge channel (24) is designed to slope down in the direction of the discharge element (25).

Description

The invention relates to a vibrating mill, in particular disc vibrating mill, with a milling unit, wherein the milling unit has a lowerable grinding floor and a discharge floor.

Vibratory mills or grinding units of the type in question are, for example DE 8713602U are known and used for example for grinding a sample of pourable, granular material in the course of preparation of the sample for desired analyzes.

In view of the known prior art, a technical problem of the invention is seen in a vibration mill of the type in question in such an advantageous manner further that a constant homogeneous grinding result can be achieved.

This problem is solved first and foremost by the subject matter of claim 1, wherein it is based on the fact that the discharge chute is formed sloping towards the discharge element. Such a sloping formation is preferably provided at least in the region of the gutter bottom, but can also detect further cross-sectional areas depending on the gutter configuration and in particular gutter cross-section. As a result of the sloping configuration, the conveyance of the ground material from the discharge floor via the discharge chute to the discharge element is improved. It is achieved such a constant homogeneous grinding result, especially in view of lower fluctuations in the discharge rates (or minor deviations from the millbase used) as well as fine grain and reproducibility. Further features of the invention are explained below, also in the description of the figures, in their preferred association with the subject matter of claim 1 or with features of further claims.

Thus, it is provided in a preferred development that the discharge chute is continuously circumferentially sloping, with the exception of at least one step-shaped transition, in particular with the exception of at least one wall-like separation region between a gutter start region and a gutter end region, in which the gutter bottom is lower than in the gutter region. The discharge chute is preferably formed in the form of a helix. There is the possibility that the discharge chute extends along the predominant extent of the grinding floor, in particular along the substantially entire or even the entire circumference of the grinding floor. In this case, the sloping channel bottom or optionally the entire discharge chute can follow the inclined course of a helical or spiral turn or a section of such a turn. In an advantageous embodiment, it is provided that the discharge chute follows the outline of a circular line along the predominant circumference of the grinding floor and extends in a groove end area deviating outwardly from the circular line, in particular running tangentially to the circular line. In order to supply the material to be ground preferably from the deepest point of the channel bottom to the discharge element, it is expedient that the boundary of the discharge channel has an opening in the channel end region, wherein the opening can preferably lie in the channel bottom and / or in the region of the radially outer channel wall. It is also preferred that the channel bottom is located in the channel start region below the surface of the grinding ground. For further embodiment, there is the possibility that the discharge chute is adjacent to the grinding floor in the radial direction or overlapping this in projection.

In addition, the discharge tray is preferably fixedly connected, in particular in one piece, with a cylinder part, in which a piston used for lowering or raising the grinding floor, for example further pneumatically / fluidically actuated piston, is guided.

A further improvement with regard to the grinding result is achieved in that the discharge tray can be blown out, so further can be cleaned using a fluid, for example with air, but also by means of a fluid such as nitrogen. Thus, also residual regrind is blown in the direction of the discharge chute. Furthermore, it is also possible to provide exhaust nozzles pointing tangentially into the discharge chute, which support the transport of the ground material from the discharge tray in the direction of the discharge element. Along the circumference of the discharge chute one or more, preferably evenly spaced, tangentially oriented discharge nozzles may be provided.

Between a grinding wall and the grinding ground results in the lowered state of the grinding ground, a discharge gap. If necessary, further blowing nozzles are arranged in the discharge floor or, if appropriate, arranged for impinging the discharge gap and for blowing out ground material into the discharge chute. These blowing nozzles, in particular the further blowing nozzles acting on the discharge gap, are directed radially inward. Along the circumference of the discharge chute, one or preferably a plurality of preferably uniformly spaced, radially oriented blow-off nozzles may be provided.

Furthermore, it is also possible to blow out the grinder itself with fluid, for example with compressed air or nitrogen, in particular through nozzles leading thereto or into the grinding chamber.

In a further preferred embodiment, the piston has two piston sections of different diameters, wherein the piston walls of the piston sections overlap while leaving a vertically opening recess for a collar. It is preferably provided that the collar is formed coaxially to the cylinder part on the underside of the outlet bottom and sealingly against the upper piston portion of comparatively smaller diameter, wherein it is provided in particular that the insertion recess is geometrically, in particular laterally form-fitting, adapted to the collar. With respect to the piston, it is preferred that this is guided at the lower piston portion of comparatively larger diameter by means of at least one piston guide ring in the cylinder part. By this measure can be compared to a leadership of the piston only by means of sealing rings reduce the tolerance field and thereby achieve a more accurate centering, whereby in particular the closing behavior of the grinding ground is improved. There is the possibility that seals are arranged on this piston section in Kolbenaxialrichtung on one or both sides of the piston guide ring for sealing with the cylinder part. It is further preferred that the collar and the wall of the cylinder part form lateral boundaries of a ring-like extending pressure chamber of the cylinder part, in which protrudes the upper edge of the upper piston portion. The sealing of this pressure chamber can be done on the one hand by the seal or seals on the lower piston portion of comparatively larger diameter and on the other hand by the sealing engagement of the collar on the upper piston portion of comparatively smaller diameter. The described override-Einahrausbildung for the upper edge of the piston piston extension is made possible, whereby even with the arrangement of a piston guide ring and adjacent seals by the said overlaps in the axial direction of the piston still a compact design is possible. This also creates the possibility of existing vibrating mills with predetermined or limited space with corresponding components for improvement to retrofit the piston guide.

It is further provided that the grinding wall is held positively. The grinding soil is sealed relative to a side wall of the discharge chute. This more preferably both in the lowered and in the raised position of the same.

Fig.1

eine Schnittansicht durch eine erfindungsgemäße Schwingmühle gemäß einer bevorzugten Ausführungsform entlang Schnittlinie I-I in Fig. 3 bei abgesenktem Mahlboden;

Fig. 1a

die Anordnung aus Fig. 1, jedoch bei für den Mahlbetrieb ver- gleichsweise angehobenem Mahlboden;

Fig. 2

in Seitenansicht einen Austragsboden der Schwingmühle in Einzel- darstellung;

Fig. 3

die Draufsicht hierzu mit Blick auf eine Austragsrinne;

Fig. 4

den Schnitt gemäß der Linie IV-IV in Fig. 3;

Fig. 5

die Schnittdarstellung gemäß der Linie V-V in Fig. 3;

Fig. 6

die Schnittdarstellung gemäß der Linie VI-VI in Fig. 3;

Fig. 7

den Querschnitt durch einen Kolben der Schwingmühle;

Fig. 8

den Querschnitt durch einen Mahlboden der Schwingmühle;

Fig. 9

eine Querschnittdarstellung einer Mahlwand der Schwingmühle;

Fig.10

den Querschnitt durch einen Stützring der Schwingmühle;

Fig. 11

den Querschnitt durch einen Gehäusedeckel der Schwingmühle;

Fig. 12

eine Schnittansicht entlang Schnittlinie XII-XII in Fig. 3;

Fig. 13

eine Ausschnittsvergrößerung von Detail XIII aus Fig. 1 und

Fig. 14

einen Teilschnitt entlang Schnittlinie XIV-XIV in Fig. 3.

The invention is explained in more detail below with reference to the attached drawing, which represents only one exemplary embodiment. It shows:

Fig.1

a sectional view through a vibrating mill according to the invention according to a preferred embodiment along section line II in Fig. 3 with lowered grinding soil;

Fig. 1a

the arrangement Fig. 1 , but with the grinding ground raised comparatively for the grinding operation;

Fig. 2

in side view, a discharge of the vibratory mill in a single representation;

Fig. 3

the top view for this purpose with a view to a discharge chute;

Fig. 4

the section according to the line IV-IV in Fig. 3 ;

Fig. 5

the sectional view along the line VV in Fig. 3 ;

Fig. 6

the sectional view according to the line VI-VI in Fig. 3 ;

Fig. 7

the cross section through a piston of the vibratory mill;

Fig. 8

the cross section through a grinding floor of the vibrating mill;

Fig. 9

a cross-sectional view of a grinding wall of the vibrating mill;

Figure 10

the cross section through a support ring of the vibratory mill;

Fig. 11

the cross section through a housing cover of the vibrating mill;

Fig. 12

a sectional view taken along section line XII-XII in Fig. 3 ;

Fig. 13

an enlarged detail of detail XIII Fig. 1 and

Fig. 14

a partial section along section line XIV-XIV in Fig. 3 ,

Fig. 1 shows a cross section through the upper portion of a vibrating mill 1 according to the invention according to a preferred embodiment. This is a so-called disc vibrating mill whose grinding unit 2 represents an assembly that can be excited into vibrations by a separate oscillating drive. The grinding unit 2 includes a grinding chamber 3, which is externally bounded by a cylindrical grinding wall 4. At this closes below during the grinding operation, a substantially circular grinding soil 5 at. On this are as grinding elements a grinding ring 6 and a millstone 7. Between the grinding wall 4 and Mahlring 6 a grinding gap 8 is formed. Another grinding gap 9 is established between the grinding ring 6 and the grinding stone 7. This allows a lateral relative movement of Mahlring 6 and millstone 7 both to each other and with respect to the grinding wall. 4

To the grinding wall 4 includes radially outside a housing ring 10, which is screwed on the underside with a discharge base 12 forming a housing base 11 and thereby connected to a drive flange 13. To the drive flange may be any, commonly used for vibrating mills and therefore not connected in the figures with oscillating drive. On the upper side, the housing ring 10 is screwed to a housing cover 14, which is centered in a form-fitting manner to the housing ring during placement by means of an annular projection 32.

The grinding wall 4 is formschlussgehaltert inside wall of the housing ring 10, held in the axial direction between an upper, radially inwardly projecting collar of the housing ring 10 and the underside by a provided support ring 29.

On the housing base 11, a cylinder part 15 is formed on the underside. In this, a piston 16 is guided by means of a piston guide ring 31, which enters the bottom of the grinding base 5 on the underside. Via a fluidic control of the piston 16, the grinding base 5 can be raised or lowered over it.

The piston 16 has two successive piston sections 17 and 18 in axial extension. These have different diameters, wherein the grinding base 5 facing piston portion 18 is reduced in diameter relative to the piston portion 17. The piston walls 19 and 20 of the piston sections 17 and 18 overlap, leaving a vertically upwardly opening, annular Einfahrrausnehmung 21. In this emerges a coaxial with the cylinder portion 15 below the outlet bottom 12 formed, sealingly against the upper piston portion 18 passing collar 22. As already mentioned, is about a fluidic Actuation of the piston 16 via this the grinding floor 5 can be raised or lowered. For this purpose, a pressure chamber 33 in the form of an annular cavity is formed between the cylinder part 15 and the piston 16. This is an annular groove formed on the underside of the discharge base 12, in which the upper edge 34 of the lower piston portion 17 engages from the underside as an annular projection of the piston 16. The pressure chamber 33 is connected via a line 35 with a connecting piece 36 in connection, so that can be applied to lower the grinding floor 5, an overpressure. The piston 16 has at its lower end face a radially inner annular projection, which in the in FIG. 1 shown lower travel position forms a limit stop with a plate 53. In this case remains radially adjacent to the annular projection serving as a further pressure chamber 50 annular gap. This is connected via a line 54 with a connecting piece 52 in connection, so that can be applied to raise the grinding floor 5 to the pressure chamber 50, a pressure. In this case, the pressure chamber 50 continues in the piston interior 51 in the embodiment shown. The sealing of the pressure chamber 33 by means of two ring seals 37, 38, of which one is inserted into the upper edge 34 of the piston and in the collar 22. The collar 22 in the exemplary embodiment, as can also be seen from the figures, is the ring section 22, so that in this context the terms collar and ring section are also interchangeable.

During the grinding process, the grinding base 5, which is acted on at the underside by the piston 16, comes sealingly against the grinding wall 4 at the edge Fig. 1a shown. After a in FIG. 1 illustrated lowering of Piston 16 and on this of the grinding plate 5 a discharge gap 23 is circumferentially released, by which further vibrational excitation the comminuted material passes into an annular discharge channel 24 in plan. In order to prevent finely ground (not shown in the figures) regrind can penetrate into the gap between the grinding floor 5 and the discharge floor 12, the grinding floor 5 is circumferentially covering provided with a ring seal 39. This is supported in the region of its upper end radially inward against a cylinder wall of the grinding floor 5 and in the region of its lower end end face against the discharge floor 12 from. This seal also contributes to a quantitatively more accurate and reproducible grinding material output or to achieving more homogeneous grinding results. The Austragsrinne 24 is circumferentially sloping down to a discharge element 25, this further helically continuous falling continuously, with the exception of a step-shaped transition 26, between the gutter start region lowest height and the discharge element 25 associated Rinnenendbereich largest height.

FIG. 3 shows in a plan view that the discharge chute 24 is formed continuously continuously sloping, with the exception of a wall-like separation region 26 'between a groove start region 40 and a gutter end portion 41, in which the groove bottom 42 is lower than in the gutter region 40. In this case, the level difference of the gutter bottom 42 between the gutter starting region and the gutter end region can be, for example, 10 mm, but may also assume different values. Along the vast circumference of the grinding floor 5, the discharge chute 24 extends following a circular line. Only in the gutter end region 41 does the discharge chute 24 deviate outward from the circular line along a tangential line 43, the boundary 44 of the discharge chute 24 (cf. FIGS. 4 and 12 ) in the region of the outer channel wall has an opening 45 through which the material to be ground to the discharge element 25 and passes therethrough. FIG. 12 whose Cut something of FIG. 1 deviates (cf. FIG. 3 ), also shows that the opening 45 adjacent to the discharge element 25 is located in the gutter end region 41 at the lowest point of the gutter bottom 42.

The discharge floor 12 or the discharge chute 24, moreover also the discharge gap 23 resulting after lowering the grinding floor 5, can be blown out by means of compressed air. For this purpose, blow-off nozzles 27 and 28 are provided, wherein the blow-off nozzles 27 point tangentially into the discharge chute 24, this further in the direction of inclination of the discharge chute 24. By means of the tangentially introduced blow holes or the blow-off nozzles 27, the discharge and the cleaning can be improved. The blow-off nozzles 28 are directed radially, in particular for blowing out or for cleaning the area of the discharge gap 23, for example with compressed air.

FIG. 3 illustrates that in the example chosen on the discharge tray 12 each three blow nozzles 27 are provided for tangential blowing and three blow nozzles 28 for radial blowing. In this case, along the circumference of the distance between each two identical nozzles by a multiple greater than the distance between two closely adjacent nozzles 27 and 28. In the sectional view of FIG. 1 For example, a connection 46 for a radial exhaust nozzle 28 and a connection 47 for a tangential exhaust nozzle 27 are shown. It is also clear that the piston 16 is fixed at its upper end wall 48 by means of a plurality of circumferentially distributed screws 49 with the grinding base 5.

The entire device is essentially tight. It takes place at the same time on the Austragselement 25 an active suction instead. The extracted air quantity may be equal to or per unit of time also slightly larger than the amount of air blown. It is also a pulse-like bubbles possible.

In the area between the grinding wall 4 and the housing ring 10 further cable routes 30 are provided for a cooling not shown. With regard to this cooling is to the German patent application with the file number DE 10 2006 042 825 A1 directed.

Furthermore, the grinding unit 2 of the vibrating mill 1 can be supported via a sliding guide and further optionally have speed-changing means. In this regard, the German patent applications with the file number DE 10 2007 017131 A1 and DE 10 2006 042 823 A1 directed.

Like the characters and especially Fig. 3 show the vibrating mill 1 in the exemplary embodiment selected distributed on the circumference of the discharge channel 24 has a plurality, in the concrete example six, exhaust nozzles 27, 28. The respective positions of the exhaust nozzles along the circumference of the Austragsrinne are Fig. 3 refer to. It will be understood that the three tangentially oriented purging nozzles 27 are spaced equidistantly from each other along the circumference so that the angle formed between each two adjacent positions is 120 degrees, respectively. The same applies to the three radially oriented exhaust nozzles 28, so that there is a uniform position distribution for both nozzle types. The blow-off nozzles 27 and 28 are each formed as recesses or bores in the discharge floor 12. The contour of the tangentially oriented exhaust nozzles 27 can also be schematic Fig. 3 be removed and includes on the exit side directly into the Austragsrinne 24 opening, relatively narrow bore 55 and an adjoining the nozzle inlet side, compared with cross-sectional larger and provided with internal connection bore 56, to which the example. In Fig. 1 visible connection 47, which may for example be connected to a compressed air line, can be connected. The longitudinal contour of the radially oriented exhaust nozzles 28 is the Figures 3 and 13 removable. Accordingly, this contour also comprises a relatively narrower bore 57 at the nozzle exit side and a connecting bore 58, which is provided with an internal thread, adjoining the nozzle inlet side, into which the connection 46, for example a compressed air supply line, is connected by screwing.

Regarding Fig. 13 is further shown that the nozzle outlet side holes 57 of the radially oriented exhaust nozzles 28 open into a ventilation duct 59, which in the circumferential direction U (see. Fig. 3 ) of the discharge chute extends. At this closes at the radially inner edge down to a vertically extending gap 60 at. In the in Fig. 13 The diameter of the bore 57 is a multiple of the width of gap 60. On its underside joins to the gap 60, the discharge chute 61 at the bottom and at the Pages of the discharge chute 24 is bounded. It is also clear that the lower gap end 62 is adjacent to the radially outer boundary wall 63 of the discharge chute 24 at its upper end.

Again with respect to Fig. 3 It is clear that along the circumference of the discharge chute 24 in the direction of their deflection, which in Fig. 3 extends clockwise, behind each of a tangentially oriented exhaust nozzle 27 each have a radially oriented exhaust nozzle 28 is located. In the example chosen, one each tangentially and one each radially oriented exhaust nozzle 27, 28 in the circumferential plane of Fig. 3 only a circumferential angle in the range of about 5 to 10 degrees (depending on the method of measurement), that is significantly lower than the aforementioned Distance angle of 120 degrees between similar exhaust nozzles is. In this respect, one can also speak of nozzle pairs of one tangential and one radially oriented outlet nozzle 27, 28. From the Figures 2 . 4 . 13 and 14 As well as from the foregoing, it is also clear that with respect to a perpendicular to the circumferential direction U lying cross section of the discharge chute 24, so for example. On the cross section of Figures 13 and 14 The nozzle exit of tangentially oriented purging nozzles 27, which is the radially inner end of the bore 55, opens at a smaller vertical distance from the channel bottom 42 into the discharge chute 24 than the split end 62, ie as the fluid outlet of radially oriented in the example In the selected embodiment, the tangentially oriented exhaust nozzles 27 in the discharge floor 12 are all in the same absolute vertical height, ie have due to the slope of the discharge a different vertical distance from the channel bottom 42. Alternatively, it could also be provided that tangentially oriented Purging nozzles 27 each in the same vertical, ie to the plane of Fig. 3 vertical, opening the channel bottom 42 in the discharge chute 24.

LIST OF REFERENCE NUMBERS

1

vibratory mill

2

grinding unit

3

grinding chamber

4

grinding wall

5

Mahlboden

6

grinding ring

7

millstone

8th

grinding gap

9

grinding gap

10

housing ring

11

housing base

12

discharge base

13

drive flange

14

housing cover

15

cylinder part

16

piston

17

piston section

18

piston section

19

piston wall

20

piston wall

21

Einfahrausnehmung

22

ring section

23

discharge slot

24

discharge chute

25

discharge element

26

crossing

26 '

separating region

27

air nozzles

28

air nozzles

29

support ring

30

line paths

31

Piston guide ring

32

annular projection

33

pressure chamber

34

edge

35

management

36

connector

37

ring seal

38

ring seal

39

ring seal

40

Rinne initial region

41

Rinnenendbereich

42

channel base

43

tangent

44

limit

45

opening

46

connection

47

connection

48

bulkhead

49

screw

50

pressure chamber

51

Piston interior

52

connector

53

plate

54

management

55

drilling

56

connection bore

57

drilling

58

connection bore

59

ventilation duct

60

gap

61

Austragsrinnenkammer

62

gap end

63

boundary wall

Claims (15)

1. Vibration grinding mill (1), in particular a vibratory disc mill, comprising a mill unit (2), the mill unit (2) comprising a lowerable mill base (5) and a discharge base (12), characterised in that the discharge base (12) further comprises a peripheral discharge groove (24) for conveying the ground stock to or through a discharge element (25), and in that the discharge groove (24) is formed so as to slope downwards towards the discharge element (25).
2. Vibration grinding mill according to claim 1, characterised in that the discharge groove (24) is formed so as to slope downwards continuously peripherally, except for at least one in particular step-shaped transition (26), in particular except for at least one wall-like separating region (26') between a starting region (40) of the groove and an end region (41) of the groove, in which end region the groove base (42) is lower than in the starting region (40).
3. Vibration grinding mill according to one or more of the preceding claims, characterised in that the discharge groove (24) extends along most of the periphery of the mill base (5), in particular along substantially or almost the entire periphery of the mill base (5).
4. Vibration grinding mill according to one or more of the preceding claims, characterised in that the discharge groove (24) extends along most of the periphery of the mill base (5), following a circular line in the plan view and deviating outwards from, in particular extending tangentially to, the circular line in an end region (41) of the groove.
5. Vibration grinding mill according to one or more of the preceding claims, characterised in that the boundary (44) of the discharge groove (24) in the groove end region (41) has an opening (45) in the region of the outer groove wall and/or the groove base (42).
6. Vibration grinding mill according to one or more of the preceding claims, characterised in that the groove base (42) is also located in the starting region (40) of the groove, below the surface of the mill base (5).
7. Vibration grinding mill according to one or more of the preceding claims, characterised in that the discharge groove (24) is adjacent to the mill base (5) in the radial direction or intersects said mill base in projection.
8. Vibration grinding mill according to one or more of the preceding claims, characterised in that the discharge base (12) is rigidly connected to, in particular formed in one piece with a cylinder part (15), in which a plunger (16) is guided which is used to lower the mill base (5).
9. Vibration grinding mill according to one or more of the preceding claims, characterised in that the plunger (16) comprises two plunger portions (17, 18) having different diameters and in that the plunger walls (19, 20) of the plunger portions (17, 18) overlap each other, leaving a vertically opening entry recess (21) for a collar (22).
10. Vibration grinding mill according to one or more of the preceding claims, characterised in that the collar (22) is formed on the underside of the discharge base (12) so as to be coaxial with the cylinder part (15) and engages sealingly against the upper plunger portion (18), it being provided in particular for the entry recess (21) to be geometrically adapted, in particular with a lateral positive fit, to the collar (22).
11. Vibration grinding mill according to one or more of the preceding claims, characterised in that the plunger (16) comprises two plunger portions (17, 18) having different diameters and in that the plunger (16) is guided in the cylinder part (15) by the plunger portion (17) having the comparatively larger diameter by means of at least one plunger guide ring (31).
12. Vibration grinding mill according to one or more of the preceding claims, characterised in that seals (37) for sealing to the cylinder part (15) are arranged on the plunger portion (17) in the axial direction of the plunger on one or both sides of the plunger guide ring (31).
13. Vibration grinding mill according to one or more of the preceding claims, characterised in that the collar (22) and the wall of the cylinder part (15) form lateral boundaries of an annularly extending pressure chamber (33) into which the upper edge (34) of the plunger portion (17) projects.
14. Vibration grinding mill according to one or more of the preceding claims, characterised in that the mill wall (4) is held with a positive fit.
15. Vibration grinding mill according to one or more of the preceding claims, characterised in that the mill base (5) is sealed relative to a side wall of the discharge groove (24).

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