CENTRIFUGE DRUM

Abstract

A centrifuge drum includes a drum lid, a drum base and a drum jacket. The drum jacket has discharge holes arranged in radial direction to a longitudinal axis. The drum lid and the drum base are arranged perpendicularly to the longitudinal axis diametrically opposite the drum jacket and the drum lid. The drum base and the drum jacket enclose an inner space of the centrifuge drum. The centrifuge drum, in the installed state, is rotatable in the centrifuge around the longitudinal axis, and in the operating state is rotatable around the longitudinal axis by a drive with a predeterminable rotational speed. A filter medium is disposed at an inner peripheral surface of the drum jacket, the filter medium being fixed by a fixing arrangement to the inner peripheral surface of the drum jacket. The fixing arrangement includes a fixing socket extending along a socket axis, with a fixing collar.

Claims

1. A centrifuge drum for a centrifuge for dividing a mixture into a solid material cake and a liquid phase, comprising: a drum lid, a drum base and a drum jacket forming the centrifuge drum, the drum jacket extending along a longitudinal axis of the centrifuge drum, and at the drum jacket a number of discharge holes being arranged in radial direction to the longitudinal axis with a discharge diameter, and the drum lid and the drum base being arranged perpendicularly to the longitudinal axis diametrically opposite the drum jacket, and the drum lid, the drum base and the drum jacket together enclosing an inner space of the centrifuge drum, the centrifuge drum, in the installed state, being rotatable in the centrifuge around the longitudinal axis, and in the operating state being rotatable around the longitudinal axis by a drive with a predeterminable rotational speed, and a filter medium is disposed at an inner peripheral surface of the drum jacket, the filter medium being fixed by at least one fixing arrangement to the inner peripheral surface of the drum jacket, the fixing arrangement comprising a fixing socket extending along a socket axis, with a fixing collar, and the fixing socket being arranged from the inner space of the centrifuge drum in one of the discharge holes such that the filter medium is fixed by the fixing collar to the inner peripheral surface of drum jacket in radial direction to longitudinal axis.

2. The centrifuge drum according to claim 1, wherein the filter medium is at least one of a filter cloth and a support fabric.

3. The centrifuge drum according to claim 1, wherein a first outer socket diameter of the fixing socket is larger than a drainage diameter of the discharge holes.

4. The centrifuge drum according claim 1, wherein at least one of a first outer socket diameter and a second outer socket diameter of the fixing socket is smaller than a discharge diameter of the discharge holes.

5. The centrifuge drum according claim 1, wherein the fixing socket has a length, and a socket hole is disposed over at least some the length of the fixing socket along the socket axis.

6. The centrifuge drum according to claim 5, wherein the fixing socket includes a socket groove transverse to the socket hole.

7. The centrifuge drum according to claim 6, wherein the socket groove is aligned parallel to the longitudinal axis of the centrifuge drum.

8. The centrifuge drum according claim 5, where the fixing arrangement further includes a clamping bolt, the clamping bolt being arranged in the socket hole.

9. The centrifuge drum according to claim 8, wherein the clamping bolt is a fixing screw and the socket hole includes a socket thread via which the fixing screw is screwed to the fixing socket.

10. The centrifuge drum according to claim 4, wherein one of the discharge holes includes at least one locking element, the locking element, in a radial direction to the socket axis, has a flexibly deflectable partial section, and that the fixing socket has a recess at an outer peripheral surface, in operating position, the flexibly deflectable partial section extending into the recess of the fixing socket and securing the fixing socket in direction of the socket axis.

11. The centrifuge drum according claim 1, wherein the fixing collar has a round shape.

12. The centrifuge drum according claim 1, wherein the fixing collar is an n-gon.

13. The centrifuge drum according to claim 1, wherein the filter medium is at least one of a filter cloth and a support fabric.

14. A centrifuge, comprising a centrifuge drum according to claim 1.

15. A fixing arrangement comprising a fixing socket with a fixing collar configured to fix a filter medium to an inner peripheral surface of a drum jacket of a centrifuge drum according to claim 1.

16. The centrifuge drum according to claim 5, wherein the socket hole is a socket passage hole.

17. The centrifuge drum according to claim 10, wherein the recess is a circumferential recess.

18. The centrifuge drum according to claim 1, wherein the filter medium is at least one of a textile filter cloth, a textile support fabric, a plastic filter cloth, a plastic support fabric, a polypropylene filter cloth, a polypropylene support fabric, a metal filter cloth, a metal support fabric, a composite material filter cloth, a composite material support fabric, a carbon composite filter cloth, and a carbon composite support fabric.

19. The centrifuge according to claim 14, wherein the centrifuge is at least one of a vertically oriented centrifuge, a horizontally oriented centrifuge, a continually operating centrifuge, a discontinually operating centrifuge, a peeler centrifuge, sliding discharge centrifuge, a one-stage pusher centrifuge, a multi-stage pusher centrifuge, a double pusher centrifuge and an oscillating centrifuge.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0094] The invention will be explained in more detail hereinafter with reference to the drawings.

[0095] FIG. 1 shows a prior-art centrifuge drum;

[0096] FIG. 2 shows a first embodiment of a prior-art quick-action ring:

[0097] FIG. 2A shows a second embodiment of a prior-art quick-action lock;

[0098] FIG. 3A shows a first embodiment of a prior-art centrifuge drum with a fixing groove;

[0099] FIG. 3B shows a second embodiment according to FIG. 3A;

[0100] FIG. 3C shows a third embodiment according to FIG. 3A;

[0101] FIG. 3D shows a fourth embodiment according to FIG. 3A:

[0102] FIG. 4 shows a first embodiment of a prior-art centrifuge drum with a fixing clip;

[0103] FIG. 5 shows a first embodiment of a centrifuge drum according to the invention;

[0104] FIG. 6 shows a first embodiment of a converted centrifuge drum according to FIG. 1;

[0105] FIG. 7 shows a perspective view of a fixing socket with a fixing collar;

[0106] FIG. 8A shows a detail of a first embodiment of a fixing arrangement according to FIG. 5 and FIG. 6;

[0107] FIG. 8B shows a second embodiment according to FIG. 8A;

[0108] FIG. 8C shows a third embodiment according to FIG. 8A;

[0109] FIG. 8D shows a fourth embodiment according to FIG. 8A;

[0110] FIG. 8E shows a fifth embodiment according to FIG. 8A;

[0111] FIG. 8F shows a sixth embodiment according to FIG. 8A;

DETAILED DESCRIPTION OF THE EMBODIMENT

[0112] As already mentioned, FIG. 1 to FIG. 4 show the prior art which was already discussed earlier, and no further discussion is therefore required here.

[0113] FIG. 5 shows in cross-section a partial schematic view of a first embodiment of a centrifuge drum according to the invention, which hereinafter is marked with the overall reference number 1. The reference numbers used in FIG. 5 to FIG. 8F have no apostrophe, since these figures relate to embodiments of the present invention. As already mentioned above, only the reference numbers in FIG. 1 to FIG. 4 have an apostrophe, since they refer to the prior art.

[0114] As is known from prior art, centrifuge drum 1 comprises a drum jacket 3 that actually forms the centrifuge drum 1, with discharge holes 31 through which the liquid phase is to be centrifuged off from centrifuge drum 1, and a drum lid 2 through whose hole 21, for example, a suspension to be dehumidified can be introduced. Furthermore, centrifuge drum 1 is also formed by a drum base (not shown for the sake of clarity) coupled with a rotary drive (also not shown) for driving centrifuge drum 1.

[0115] Drum jacket 3 extends cylindrically along the longitudinal axis 4 of centrifuge drum 1, and drum lid 2 and the drum base are arranged vertically to longitudinal axis 4, diametrically opposite at drum jacket 3, forming the two end surfaces of the cylindrical centrifuge drum 1, drum lid 2, the drum base and drum jacket 3 together enclose an inner space 11 of centrifuge drum 1.

[0116] In the case of centrifuge drum 1 according to the invention, shown in FIG. 5, a filter cloth 6 is fastened to an inner peripheral surface 5 of drum jacket 3 with a number of fixing arrangements 12. The fixing arrangements 12 each comprise a fixing socket 14 extending along a socket axis 13 with a fixing collar 15 and a clamping bolt 16. The fixing sockets 14 are arranged from inner space 11 of centrifuge drum 1 in one of the discharge holes 31 such that the filter cloth 6 is fixed by fixing collar 15 on the inner peripheral surface 5 of drum jacket 3 in radial direction to the longitudinal axis 4. Clamping bolt 16 is designed as a fixing screw 161, screwed via a socket thread to fixing socket 14. In the installed state, fixing screw 161 causes fixing shaft 17 of fixing socket 14 to spread apart, thus clamping fixing socket 14 to an inner surface of discharge hole 31.

[0117] Related to the axial direction of centrifuge drum 1, the fixing arrangements 12 are arranged at both ends of centrifuge drum 1, i.e. at the upper and lower side of drum jacket 3. Fixing arrangements 12 are arranged at regular intervals in peripheral direction 8 of drum jacket 3 in a number of discharge holes 31 in such a way that filter cloths 6 can be equally fixed on the inner peripheral surface 5 of drum jacket 3.

[0118] For installation, filter cloth 6 is then placed on the inner peripheral surface 5 of centrifuge drum 1, fixing sockets 14 are inserted in the appropriate discharge holes 31 and secured by fixing screws 161 in axial direction to socket axis 13, thus fixing filter cloth 6 to the inner peripheral surface 5 of drum jacket 3 by fixing collars 15.

[0119] Thus FIG. 5 clearly shows that thanks to the present invention, there is no need for a channel or additional holes in drum jacket 3 for fastening filter cloth 6.

[0120] With the embodiment shown in FIG. 5 it is quite conceivable that instead of the filter cloth, a support fabric can be fastened to the inner peripheral surface of the drum jacket with a number of fixing arrangements.

[0121] FIG. 6 shows in cross-section a schematic view of a part of a first embodiment of a converted centrifuge drum according to FIG. 1.

[0122] As known from prior art, centrifuge drum 1 comprises a drum jacket 3 forming centrifuge drum 1, with discharge holes 31, through which the liquid phase to be centrifuged off is discharged from centrifuge drum 1, and a drum lid 2 through which a suspension to be dewatered can be introduced, for example through hole 21. Furthermore, the prior-art centrifuge drum 1 is formed by a drum base (not shown in FIG. 6 for the sake of clarity) which is coupled with a rotary drive (also not shown) to drive centrifuge drum 1. Drum jacket 3 extends cylindrically along longitudinal axis 4 of centrifuge drum 1, and drum lid 2 and the drum base are arranged vertically to the longitudinal axis 4, diametrically opposite drum jacket 3, thus forming the two end surfaces of cylindrical centrifuge drum 1. Drum lid 2, the drum base and drum jacket 3 together enclose an inner space 11 of centrifuge drum 1.

[0123] At an inner peripheral surface 5 of drum jacket 3, a filter medium 6, in the present case a textile filter cloth 6, is provided, whereby two different fastening methods are used to fix filter cloth 6: the fastening method known from the centrifuge drum shown in FIG. 1, and fastening method according to the invention.

[0124] Using the prior-art fastening method, centrifuge drum 1, as described above in relation to FIG. 1, comprisesat both ends of inner peripheral surface 5 of drum jacket 3a cut-in channel 700 in which filter cloth 6 is fixed with a clamping ring 10. Related to the axial longitudinal direction 4, a circumferential hollow seam 61 is disposed at both ends of filter cloth 6 in peripheral direction 8, into which clamping ring 10 is inserted prior to installation of filter cloth 6 in centrifuge drum 1.

[0125] For fixing filter cloth 6, centrifuge drum 1 also comprises a large number of fixing arrangements 12 according to the invention, which are arranged at regular intervals in peripheral direction 8 of drum jacket 3 in a number of discharge holes 31. The fixing arrangements 12 each comprise a fixing socket 14 extending along a socket axis 13, with a fixing collar 15 and a clamping bolt 16. Fixing sockets 14 are arranged from interior space 11 of centrifuge drum 1 in one of the discharge holes 31 such that filter cloth 6 is fixed not only by the two clamping rings 10, but also by fixing collar 15 to the inner peripheral surface 5 of drum jacket 3 in radial direction to longitudinal axis 4. Clamping bolt 16 is designed as a clamping pin 162, which is hammered or pressed into a socket hole 19 of fixing socket 14. Clamping pin 162 causes a fixing shaft 17 of fixing socket 14 to spread apart, which causes clamping between fixing socket 14 and an inner surface of discharge hole 31.

[0126] For the sake of clarity, FIG. 6 illustrates only the fastening of filter cloth 6 in the area of drum lid 2. On the side diametrically opposite drum lid 2, i.e. in the area of the drum base, filter cloth 6 is also fixed with a clamping ring 10 and a large number of fixing arrangements 12 according to the invention, to the inner peripheral surface 5 of drum jacket 3.

[0127] For installation, filter cloth 6 is placed on inner peripheral surface 5 of centrifuge drum 1, the hollow seam 61 is inserted with clamping ring 10 into channel 700 on drum lid 2 and the drum lid (not shown and clamping ring 10 is fixed, for example with a quick-action device, that is actually prior art and was already discussed above. Furthermore, the fixing sockets 14 are inserted into the appropriate discharge holes 31 and secured by clamping pin 162 in axial direction to socket axis 13, which additionally fixes filter cloth 6 to the inner peripheral surface 5 of drum jacket 3 by fixing collar 15 of fixing socket 14. Thus, FIG. 6 explicitly illustrates that the present invention allows the combination of two different fastening methods, such that a prior-art centrifuge drum can be retrofitted with a fixing arrangement 12 according to the invention.

[0128] FIG. 7 shows a perspective view of a fixing socket 14. Fixing socket 14 comprises a fixing shaft 17 and a fixing collar 15. Fixing shaft 17 extends along a socket axis 13 and has a round profile with an outer socket diameter 20. As FIG. 5 and FIG. 6 indicate, in the installed state, fixing socket 14 with fixing shaft 17 extends into one of the discharge holes 31 of drum jacket 3 such that fixing collar 15 clamps filter cloth 6 or fixes it to the inner peripheral surface 5 of drum jacket 3. Fixing socket 14 has a socket hole 19 along socket axis 13. Fixing socket 14 also has a socket groove 21 across socket hole 19. Socket groove 21 is arranged on fixing shaft 17 of fixing socket 14 and extends from a free end of fixing shaft 17 in the direction of fixing collar 15. Thanks to socket groove 21, fixing shaft 17 can be spread apart in the installed state, which improves the clamping effect of fixing socket 14 in discharge hole 31. In this embodiment, the fixing collar has a round form.

[0129] FIG. 8A to FIG. 8F show an enlargement of detail D shown in FIG. 5 and FIG. 6, where the above named figures illustrate different embodiments of fixing arrangement 12 according to the invention.

[0130] FIG. 8A shows a first embodiment of fixing arrangement 12 according to the invention. Fixing arrangement 12 comprises a fixing socket 14 and a fixing screw 161 in form of a countersunk screw. Fixing socket 14 extends along a socket axis 13 and includes a socket hole 19 with a socket thread. Via the socket thread, fixing screw 161 is screwed together with fixing socket 14. In the installed state of fixing socket 14, fixing screw 161 causes an outer socket diameter 20 of fixing socket 14 to spread apart which allows clamping between fixing socket 14 and an inner surface 18 of discharge hole 31. Thanks to this clamping, filter cloth 6 is fixed by fixing collar 15 of fixing socket 14 to the inner peripheral surface 5 of drum jacket 3.

[0131] As FIG. 8B indicates, the countersunk screw can also be replaced by a stud screw to produce the clamping effect between fixing socket 14 and inner surface 18 of discharge hole 31.

[0132] FIG. 8C shows another embodiment of the fixing arrangement 12 according to the invention. Here, the fixing arrangement 12, in comparison with the embodiments shown in FIG. 8A and FIG. 8B, in addition to fixing socket 14 and fixing screw 161 show a truncated expansion wedge 23 with an inner thread. Fixing socket 14 has a socket hole 19 without inner thread, whereby socket hole 19, at a free end of fixing socket 14, becomes a widening conical hole 24. The truncated expansion wedge 23 is designed to fit conical hole 24 and in the installed state forms a positive fit with conical hole 24. If fixing screw 161 is screwed into the inner thread of expansion wedge 23, fixing socket 14 spreads out, achieving a clamping between fixing socket 14 and inner surface 18 of discharge hole 31. Also in this embodiment, filter cloth 6 is fixed due to clamping by a fixing collar 15 of fixing sockets 14 to the inner peripheral surface 5 of drum jacket 3.

[0133] According to FIG. 8D, fixing arrangement 12 canin addition to fixing socket 14have a clamping bolt 16 in the form of a clamping pin 162. Fixing socket 14 corresponds to fixing socket 14 shown in FIG. 7, whereby clamping pin 162 is hammered or pressed into a socket hole 19 of fixing socket 14. In the installed state, clamping pin 162 causes fixing socket 14 to spread apart, achieving a clamping effect between fixing socket 14 and an inner surface 18 of discharge hole 31. As in the preceding embodiments, filter cloth 6 is clamped by a fixing collar 15 of fixing socket 14 to the inner peripheral surface 5 of drum jacket 3. But as an alternative it is also possible that clamping bolt 16, instead of being a clamping pin 162, is designed as a rivet that is riveted to fixing socket 14.

[0134] In the embodiments shown in FIG. 8E and FIG. 8F, fixing arrangement 12 is additionally includes a separate sleeve 25 inserted in discharge hole 31 of drum jacket 3. In this case, sleeve 25 is designed as a dowel.

[0135] In FIG. 8E, fixing socket 14 has the form of a screw. In the installed state, fixing socket 14 is screwed into sleeve 25 inserted in discharge hole 31, whereby filter cloth 6 is fixed by a fixing collar 15 to the inner peripheral surface 5 of drum jacket 3. To provide fixing socket 14 in discharge hole 31 with a firm clamping point, a fixing shaft 17 of fixing socket 14 has two different outer socket diameters, a first larger, outer socket diameter 201 and a second smaller outer socket diameter 202, whereby the first larger outer socket diameter 201 includes an outer thread. Due to the two different socket diameters, it is achieved that fixing socket 14 is wedged into discharge hole 31 in the position of the first larger socket diameter 201.

[0136] As FIG. 8F indicates, sleeve 25 in discharge hole 31 can also include partial section 26 that is flexibly deflectable in radial direction to socket axis 13, and fixing socket 14 can have a circumferential recess 27 at an outer peripheral surface, whereby in operating position, the flexibly deflectable partial section 26 extends into recess 27 of fixing socket 14, securing fixing socket 14 in the direction of socket axis 13. This means that fixing socket 14 is not fastened, as shown in FIG. 8E, via a screw connection, but via a plug-in connection in one of the discharge holes 31. Fixing socket 14 has a first outer socket diameter 201, with which fixing socket 14 abuts to sleeve 25, and in the area of recess 27, it has a second outer socket diameter 202.

[0137] In the embodiments of a fixing arrangement 12 according to the invention, shown in FIG. 8A to FIG. 8F, a first and/or a second outer socket diameter 201, 202 of fixing sockets 14 is smaller than the discharge diameter of discharge holes 31. Of course, an embodiment of fixing socket 14 is also possible where an outer socket diameter 20 of fixing socket 14 is larger than the discharge diameter of discharge holes 31, such that fixing socket 14 is hammered or pressed into discharge hole 31.

[0138] It is self-evident that the characteristics of the especially preferred embodiments of the centrifuge drum described above as examples can also be combined in advantageous ways, depending on requirements and can in principle be applied to all known types of centrifuges. In particular, a centrifuge drum according to the invention can be used advantageously in a vertically or horizontally oriented centrifuge, in a continuously or discontinuously operating centrifuge, especially in a peeler centrifuge, a sliding discharge centrifuge, a one-stage or multi-stage pusher centrifuge, a double pusher centrifuge or in an oscillating centrifuge.