Title of Invention

SEPARATOR WHEEL FOR AN AIR SEPARATOR

Abstract

Separator wheel (20) for an air separator which on its periphery has channels (12) through which separation air loaded with fine and coarse particles flows through the separator wheel (20) from the outside to the inside and in which the separation air loaded with fine particles is discharged in the axial direction from the separator wheel (20) , characterized in that the channels (12) in axially different radial planes have different angles (a) to the radial direction of the separator wheel

Full Text

The invention relates to a separator wheel for an air separator which on its periphery has channels, through which separation air loaded with fine material flows through the separator wheel from the outside to the inside and in which the separation air loaded with fine material is discharged in the axial direction from the separator wheel. Separators are designed to separate the separation material into fine material and coarse material; this can be done for example as described in EP-A1 552 837 by flow taking place through the separator wheel of an air separator roughly radially from the outside to the inside, after which the separation air loaded with fine material is discharged in the axial direction from the separator wheel. The rotation of the separator wheel and the resulting centrifugal forces in the channels or in the area of the outer ports of the channels accelerate the coarse material to the outside and it cannot be discharged to the inside with the separation air and the fine material. Thus the problem arises that due to the higher flow velocities or greater pressure difference in the area of the axial outflow end of the separator wheel, more coarser separation material is removed at the same time than in the 1A middle area of the separator wheel or its area away from the outflow end, so that separation or classification of the separation material into coarse material and fine material does not often take place as exactly as desired. Here it can be stated that on the axial ends of the separator wheel, due to the edge flow, much larger particles are entrained than is the case in the middle of the separator wheel. In interaction with the separator housing therefore backflows also occur which cause undefined separation as a result. If the practical results are compared to the theoretical calculations after Stokes, it can be easily recognized that in practice the largest particles in the fine material are larger by several fold than under ideal conditions, science itself however having proven that particle sedimentation after Stokes takes place. To solve this problem, in EP-A1 552 837 it was suggested that within the separator wheel a distributor tube be placed in which there is a plurality of openings, the size of the openings increasing more and more away from the axial outflow end of the separator wheel. Due to the smaller openings near the outflow end the flow resistance is higher than in the area away from the outflow end, so that in this way more constant behavior of the fiow velocity or the acting underpressure is achieved within the separator wheel over its axial length. However, the solution suggested in EP-A1 552 837 has the disadvantage that power consumption of the separator is 2 increased by the openings in the distributor tube which act as chokes ; this is especially disadvantageous at high flow velocities. On the other hand, the larger particles should be repelled upon entry into the channels on the periphery of the separator wheel; this is not done in this approach. Therefore the object of the invention is to make available a separator wheel of the initially mentioned type with which separation behavior as constant as possible can be achieved over the axial length of the separator wheel. The present invention provides a separator wheel for an air separator which on its periphery has channels through which separation air loaded with fine and coarse particles flows through the separator wheel from the outside to the inside and in which the separation air loaded with fine particles is discharged in the axial direction from the separator wheel, characterized in that the channels in axially different radial planes have different angles (a) to the radial direction of the separator wheel. The object of the invention is achieved in a separator wheel of the generic type by the channels in axially different radial planes having different angles to the radial direction of the separator wheel. The varied angular inclination of the channels in the axially different radial planes on the outside periphery influences the repulsion of the stream of particles from the separation air over the axial length of the separator wheel to varying degrees. Repulsion on the outside radius of the rotor very effectively influences not only the separation air, but also the particles. In order to appropriately take into account the flow behavior which is three-dimensionally very different or in those areas along the rotor where mainly overly large particles pass, to prevent this, it is advantageous to influence to varying degrees the repulsion in axially different radial planes by channels with different angles to the radial direction of the separator wheel. 3 Thus the invention uses the property that the incident flow of separation air which is loaded with fine material toward the outer port of the channels is influenced by the angular inclination of the channels to the radial direction of. the separator wheel If therefore the channels are aligned in axially different radial planes at different angles to the radial direction of the separator wheel, the aforementioned more uniform separation properties can be achieved by the separator wheel without the need for additional means, such as a distributor tube according to EP-A1 552 837, which cause choke losses or high pressure losses In particular, in one preferred embodiment of the invention which is characterized in that the channels are inclined from the inside to the outside against the direction of rotation, it is proposed according to the invention that the angle of inclination of the channels on the outflow end of the separator wheel is larger than the angle of inclination of the channels away from the outflow end With this embodiment very good separation behavior of the separator can be achieved, since the aforementioned repulsion property acts not only on the separation air, but also on the particles to be separated. The present invention also provides a separator wheel wherein said channels are formed by openings, preferably holes, in the jacket surface of the separator wheel. The channels may be bounded by wheel blades extending in the axial direction of the separator wheel. The separator wheel preferably consists at least of two separator wheel segments and the channels of one separator wheel segment have a different angle (a) to the radial direction than the channels of the other separator wheel segments. The angle of inclination (a) of the channels to the radial direction may change from the outside to the inside The angle of inclination (a) 4 to the radial direction of the wheel blades preferably changes from the outside to the inside of the wheel blades in a curved or bent manner The channels may be inclined from the inside to the outside in a direction opposite to the direction of rotation The angle of inclination of the channels is preferably roughly between 15° and 60°, preferably between 30° and 45°, to the radial direction The angle of inclination (a) of the channels near the outflow end of the separator wheel may be greater than the angle of inclination (a) of the channels away from the outflow end There are preferably two outflow channels which adjoin the separator wheel axially on opposite sides and through which the separation air loaded with fine particles is discharged The separator wheel segments may consist of an annular disk-shaped carrier to which separator wheel blades are molded projecting in the axial direction In the separator wheel there maybe radially extending support disks between which the wheel blades are held by positive locking. The wheel blades preferably do not penetrate the support disks In the area of the outer edges of the support disks on faces there maybe recesses which hold the wheel blades with their ends. The recesses are preferably annular grooves, and wheel blades are fixed in their position in the annular grooves by spacers The invention and preferred embodiments thereof would be clear from the description given hereinafter with reference to the accompanying drawings, wherein - Figure 1 schematically shows an air separator with three segments in a longitudinal section 4A Figure 2 shows a view of the air separator from Figure 1 from the left, Figure 3 shows a partial view of a separator wheel according to the invention with five segments in a section, Figure 4 shows an axial view of a first embodiment of a separator wheel segment, Figure 5 shows an axial view of a second embodiment of a separator wheel segment, Figure 6 shows a section through one part of the separator wheel segment from Figure 5 along line VI-VI. Figure 1 schematically shows an air separator with separation wheel 2 0 according to the invention, separator wheel 20 being accommodated in housing 21 with inlet 23 for separation air with the separation material and outlet 22 for coarse material. The separation air with the separation material is discharged through axial outlet 24 . It goes without saying that instead of housing 21 shown and described in Figures 1 and 2, other forms of housings can also be used, and that the separation air and separation material can also be supplied to housing 21 separately from one another. Figure 3 shows separator wheel 20 according to the invention partially in cross section; it is composed of five separator wheel segments 1, 2 and 3. Separation air with separation material is supplied to separation wheel 20 in the direction of arrows S and separation air which is loaded with 5 fine material is discharged from the separator wheel at outflow end 13 in the direction of arrow 4 through outlet 24. In the first embodiment shown in an axial view in Figure 4 separator wheel segments 1 and 2 consist of carrier 6 which is joined to hub 8 via five spokes 7. On carrier 6 is a plurality of wheel blades 9, 9' which extend in the axial direction of separator wheel segment 1,1'. Wheel blades 9, 9' can be bent in the radial direction of separator wheel segment 1,1', as is shown using wheel blades 9, or can be curved. The wheel blades can however also be made in their simplest form as flat rotor bars, as is shown using wheel blades 9' in Figure 4. In their external area wheel blades 9, 9' have an angle of inclination a to the radial. The angle of inclination a in the outer region influences the separation behavior more dramatically than the angle of inclination in the inner region of channels 12 on the wheel blades 9. Wheel blades 9, 9' are inclined at angle a to the radial such that they are inclined from the inside to the outside in a direction opposite to the direction of rotation 10 of separator wheel 20 This inclination makes it more difficult for coarser particles of the separated material to flow through separator wheel 20 in the direction of arrow 5 from the outside to the inside, so that good separation of the separated particles is possible. After the separation air with the fine particles passes through channels 12 formed between wheel blades 9, 9' from the outside to the inside, the separation air loaded with fine particles is deflected by 90 degrees and flows in the axial 6 direction of the separator, as illustrated by arrows 11 in Figure 3. The separator wheel segment 3 shown in Figure 3 differs from separator wheel segment 1, 2, shown in Figure 4, in that the carrier 6 (Figure 4) is not jointed to the hub 8 via spokes, but via a continuous disk 14 without openings, as can be seen in Figure 3. This is necessary since separator wheel segment 3 is located on the end which lies opposite to the outflow end 13 of the separator wheel and thus forms the termination of the separator wheel. Angle of inclination a of separator wheel segments 1, 2 and 3 is greater in separator wheel segments 2 and 3 than in separator wheel segment 1 The greater angle of inclination of wheel blades 9, 9' or channels 12 formed between them increases repulsion for the separation air particle flow so that here passage of larger particles is prevented and thus improved separation behavior of the entire rotor for more accurate separation is achieved. It is stated that the separator wheel segment shown in Figure 4 does not coincide exactly with the separator wheel segments shown in Figure 3 since the separator wheel segment shown in Figure 4 is an integral part in which blades 9, 9' are molded on carrier 6. Conversely the separator wheel segments shown in Figure 3 are those in which blades 9, 9' are held by positive locking between support disks 16, 16', 16" , as can be seen in detail in Figures 5 and 6 Middle support disks 16 for this reason on their two faces 25 have peripheral grooves 26 which hold blades 9, 9' with their ends 27. To fix blades 9, 9' 7 in their position on support disks 16, there are spacers 28 which overall have an annular shape and which are inserted into groove 26 on either side of support disk 16. To hold ends 27 of blades 9, 9' spacers 28 have slots which are radially (sloped by angle of inclination a to the radial) open to the outside and in which blades 9, 9' lie. Edge-side support disks 16', 16" have a design similar to middle support disks 16, here there being one groove 26 for holding blades 9, 9' on the face towards the interior of separator wheel 20. The above described structure of separator wheel 20 of support disks 16,16' 16", between which blades 9, 9' are held by positive locking without penetrating them, has the advantage that the structure of separator wheel 20 is very stable throughout, since support disks 16 have high carrying capacity due to their continuous annular cross section. It goes without saying that this structure of a separator wheel of support disks and blades held by positive locking in between can also be used in separator wheels in which the channels between the blades have an essentially identical alignment over the entire length of the separator wheel. As can be seen in Figures 1 and 3, separator wheel segments 1, 2 and 3 are seated torsionally strong on shaft 15 via which separator wheel segments 1, 2 and 3 are driven using a drive not shown. 8 The angle of inclination of channels 12 formed between wheel blades 9, 9' is preferably between 30 and 45 degrees, but depending on the respective conditions, such as the particle size or the specific weight of the particles of the separation material or on the desired fractional ratio between coarse and fine material, it can also be above or below, for example between 15 and 60 degrees In alternative embodiments not shown in the drawings it is also possible that instead of channels 12 formed between wheel blades 9, 9' there are openings, for example, holes. Alternatively, the separator wheel need not be composed of individual segments which contain the channels, but within an integral separator wheel which is not separated by segments, or within a single separator wheel segment, there can be channels with different angles of inclination in different radial planes In another embodiment not shown in the drawings either, the separation air loaded with fine material can also be discharged on the two axial ends of the separator wheel via outflow channels in order to increase the efficiency of the separator according to the invention. 9 WE CLAIM 1. Separator wheel (20) for an air separator which on its periphery has channels (12) through which separation air loaded with fine and coarse particles flows through the separator wheel from the outside to the inside and in which the separation air loaded with fine particles is discharged in the axial direction from the separator wheel, characterized in that the channels (12) in axially different radial planes have different angles (a) to the radial direction of the separator wheel. 2 Separator wheel as claimed tn claim 1, wherein said channels (12) are formed by openings, preferably holes, in the jacket surface of the separator wheel 3. Separator wheel as claimed in claim 1 or 2, wherein said channels (12) are bounded by wheel blades (9, 9') extending in the axial direction of the separator wheel 4. Separator wheel as claimed in any one of claims 1 to 3, wherein the separator wheel consists of at least two separator wheel segments (1, 2, 3), and the channels (12) of one separator wheel segment (1, 2, 3) have a different angle (a) to the radial direction than the channels (12) of the other separator wheel segments (1,2,3) 10 5 Separator wheel as claimed in any one of claims 1 to 3 wherein the angle of inclination (a) of the channels (12) to the radial direction changes from the outside to the inside 6. Separator wheel as claimed in claim 3 or 5, wherein the angle of inclination (a) to the radial direction of the wheel blades (9, 9') changes from the outside to the, inside of the wheel blades (9, 9') in a curved or bent manner 7. Separator wheel as claimed in any one of claims 1 to 6, wherein the channels (12) are inclined from the inside to the outside in a direction opposite to the direction of rotation (10) 8. Separator wheel as claimed in any one of claims 1 to 7, wherein the angle of inclination of the channels (12) is roughly between 15° and 60°, preferably between 30° and 45°, to the radial direction 9 Separator wheel as claimed in any one of claims 1 to 8, wherein the angle of inclination (a) of the channels (12) near the outflow end (13) of the separator wheel is greater than the angle of inclination (a) of the channels (12) away from the outflow end (13) 11 10. Separator wheel as claimed in any one of claims 1 to 9, wherein there are two outflow channels which adjoin the separator wheel axially on opposite sides and through which the separation air loaded with fine particles is discharged 11. Separator wheel as claimed in any one of claims 3 to 10, wherein the separator wheel segments (1, 2) consist of an annular disk-shaped carrier (6, 6') to which separator wheel blades (9,9) are molded projecting in the axial direction 12. Separator wheel as claimed in any one of claims 3 to 10, wherein there are radially extending support disks (16, 16' , 16" ) between which the wheel blades (9, 9') are held by positive locking. 13. Separator wheel as claimed in claim 12, wherein the wheel blades (9, 9') do not penetrate the support disks (16, 16', 16"). 14 Separator wheel as claimed in claim 12 or 13, wherein in the area of the outer edges of the support disks (16, 16', 16" ) on faces (25) there are recesses (26) which hold the wheel blades (9, 9') with their ends (27) 15. Separator wheel as claimed in claim 14, wherein said recesses (26) are annular grooves, and the wheel blades (9, 9' ) are fixed in their position in the annular grooves (26) by spacers (28) 12 16. A separator wheel for an air separator, substantially as herein described, particularly with reference to and as illustrated in the accompanying drawings. 17 An air separator incorporating a separator wheel as claimed in any of 13 claims 1 to 15 Separator wheel (20) for an air separator which on its periphery has channels (12) through which separation air loaded with fine and coarse particles flows through the separator wheel (20) from the outside to the inside and in which the separation air loaded with fine particles is discharged in the axial direction from the separator wheel (20) , characterized in that the channels (12) in axially different radial planes have different angles (a) to the radial direction of the separator wheel

Documents:

01259-cal-1997-abstract.pdf

01259-cal-1997-claims.pdf

01259-cal-1997-correspondence.pdf

01259-cal-1997-description(complete).pdf

01259-cal-1997-drawings.pdf

01259-cal-1997-form-1.pdf

01259-cal-1997-form-2.pdf

01259-cal-1997-form-3-1.1.pdf

01259-cal-1997-form-3.pdf

01259-cal-1997-form-5.pdf

01259-cal-1997-pa.pdf

01259-cal-1997-priority document(others).pdf

01259-cal-1997-priority document.pdf

1259-CAL-1997-CORRESPONDENCE 1.1.pdf

1259-CAL-1997-FORM 27.pdf

1259-CAL-1997-FORM-27.pdf

1259-cal-1997-granted-abstract.pdf

1259-cal-1997-granted-acceptance publication.pdf

1259-cal-1997-granted-claims.pdf

1259-cal-1997-granted-correspondence.pdf

1259-cal-1997-granted-description (complete).pdf

1259-cal-1997-granted-drawings.pdf

1259-cal-1997-granted-form 1.pdf

1259-cal-1997-granted-form 2.pdf

1259-cal-1997-granted-form 3.pdf

1259-cal-1997-granted-form 5.pdf

1259-cal-1997-granted-letter patent.pdf

1259-cal-1997-granted-pa.pdf

1259-cal-1997-granted-priority document.pdf

1259-cal-1997-granted-reply to examination report.pdf

1259-cal-1997-granted-specification.pdf

1259-cal-1997-granted-translated copy of priority document.pdf