DE20102807U1 - rotary - Google Patents

Description

Applicant:

Company Jaudt Dosiertechnik; Maschinenfabrik GmbH Raiffeisenstr. 3-5 86167 Augsburg

Representative

Patent attorneys

Dipl.-Ing. H.-D. Ernicke

Dipl.-Ing. Klaus Ernicke

Schwibbogenplatz 2b

86153 Augsburg / Germany

Date:

File:

15.02.2001 892-18 er/ge

- 1 DESCRIPTION

Rotary valve

The invention relates to a rotary valve with the features in the preamble of the main claim.

Such a rotary valve for bulk materials is known from DE-A-195 37 429. It consists of a housing with an internal rotary valve chamber in which a rotary valve with a shaft protruding on both sides and a shaft bearing is arranged. The shaft bearings are designed as roller bearings, one of which forms the axial guide and is designed as an axial bearing and the other as a radial bearing. In this rotary valve, there is a gap in the axial direction between the rotary valve blades and the adjacent cell chamber wall. The gap size and thus the axial running clearance can only be adjusted via the axial bearing of the rotary valve shaft. Despite the presence of seals, such a shaft bearing is not optimal for some areas of application of the rotary valve. This applies to

especially bulk goods from the pharmaceutical industry. 25

It is an object of the present invention to provide an improved rotary valve.

The invention solves this problem with the features in the main claim.

The axial guide, which is separate from the shaft bearings, has the advantage that the axial position of the cellular wheel in the cellular wheel chamber and the axial running clearance can be adjusted better and more precisely. In particular, equal-sized gaps can be set on both sides.

This also ensures that there is always an axial gap and running clearance on both sides

In some applications, particularly in rotary valves in the pharmaceutical industry, such contact between rotary valves and chamber walls is undesirable because such contact generates frictional heat, which can cause thermally sensitive bulk materials to crystallize in an undesirable manner. To avoid contamination, the axial guide is also located outside the rotary valve chamber and has no contact with the bulk material.

The axial guide also has the advantage that it can be combined with an adjusting device. This enables the cellular wheel to be positioned very sensitively and precisely in the cellular wheel chamber. Tolerances in particular can be compensated for in this way. Furthermore, the adjusting device, particularly in conjunction with a spacer or shim, enables the cellular wheel lock to be dismantled for cleaning or maintenance purposes and the parts to be assembled precisely afterwards. The axial position of the cellular wheel does not need to be readjusted. It is automatically reproduced by the axial guide and the adjusting device.

By separating the axial guide and shaft bearings, it is also possible to work with simple radial bearings and to design these in particular as plain bearings. This also allows the use of lubricant-free plain bearings, which are advantageous for highly sensitive bulk materials, e.g. from the pharmaceutical industry.

Furthermore, one or more housing pockets can be arranged on the front sides of the housing, which collect small particles or dust and allow them to escape again via a drain by gravity. This can prevent such particles from sticking to the gap between the rotary vanes and the chamber wall and becoming

• · ' ♦ · J *&idigr;

lead to undesirable effects, in particular to friction effects and an undesirable increase in temperature. It is also advantageous if the cellular wheel blades have recesses in the pocket area so that the 5' gap length is limited.

Further advantageous embodiments of the invention are specified in the subclaims.

-A-

The invention is illustrated by way of example and schematically in the drawings. In detail:

Figure 1: . a longitudinal section through a

Rotary valve,

Figure 2: a cross-section through the rotary valve according to section line II-II of Figure 1,

Figure 3: an enlarged longitudinal section detail of the axial guide with adjusting device for the shaft of the cellular wheel,

Figure 4: an enlarged longitudinal section

Detailed view of the cell wheel and chamber wall in the gap area and

Figure 5: an exploded view of the individual parts

the rotary valve.

Figure 5 shows a rotary valve (1) with its various individual parts in an exploded view or assembly position. Figure 1 shows a longitudinal section in the assembled state.

The rotary valve (1) is designed and suitable for bulk materials of any kind. A preferred area of application is bulk materials from the pharmaceutical industry.

The rotary valve (1) consists of a multi-part housing (2) with an internal rotary chamber (14) in which a rotary wheel (6) with its shaft (7)

is rotatably mounted via shaft bearings (9). The cellular wheel (6) is driven in rotation by a drive, for example an electric motor with a gear box. The cellular wheel (6) has a large number of cellular wheel blades (15) evenly distributed around the circumference, which protrude radially from the shaft (7) or the cellular wheel axis (8) and which form the cells or receiving pockets for the bulk material between them. The cellular wheel (6) preferably has cells that are open at the sides and has no end plates. In an alternative embodiment, however, such end plates can be present. The cells are then only open on one side.

The housing (2) consists of a body part (12) with the internal cellular wheel chamber (14). It also has a closing nozzle or connection flange (13) at the upper inlet (3) and at the lower outlet (4), to which pipes for the bulk material can be connected. The bulk material is transported in the conveying direction (35) from the inlet (3) via the cellular wheel (6) to the outlet (4).

The housing (2) further comprises two side covers (10, 11) which cover two preferably circular lateral through-openings of the body part (12). The housing (2) also comprises a housing attachment (25) and a housing cover (26) on one side and a bushing (38) on the other side of the cellular wheel (6). The housing parts (10, 11, 12, 25, 26, 28) are mounted one behind the other in the direction of the cellular wheel axis (8) and are centered and guided by suitable guides. The housing parts are connected to one another in a suitable manner, preferably by screws indicated in Figure 1 with dot-dash lines. Screws (30) are also provided for fastening the side covers (10, 11) to the body part (12), which can alternatively or additionally also be provided with rod guides.

I * · · • • • · • · • • • I · ··· • • &igr; « · • · &phgr;♦· • • • • • • « · • • • • ' · • • &igr; · · · ···· * · t · ■ * ·

along which the side covers (10,11) can be moved and guided during disassembly.

The cellular wheel (6) has an axial guide (18), which is preferably also equipped with an adjusting device (20). The axial guide (18) serves for the precise adjustment of the running clearance or gap (37) between the lateral vane edges (16) of the cellular wheel vanes (15) and the adjacent parallel chamber wall (17). Figure 4 shows this arrangement. Preferably, this axial gap

(37) on both sides of the cellular wheel (6) are set to the same size. In this case, contact between the cellular wheel blades (15) and the chamber (17) is preferably avoided. The gap (37) is preferably small and only one or a few tenths of a millimeter wide. The axial guide (18) is arranged outside the cellular wheel chamber (14) and is located on the shaft (7). The axial guide (18) is arranged separately from the shaft bearings (9). The shaft bearings (9) are designed as pure radial bearings which allow axial movement of the shaft (7).

In the preferred embodiment, the axial guide (18) consists of a guide disk (19) attached to the shaft (7). In the simplest embodiment, the guide disk (19) can be rigidly connected to the shaft (7). In the preferred embodiment, however, it can be moved via the adjusting device (20) and allows the axial position of the impeller (6) to be adjusted and changed.

In the embodiment shown, the parallel-walled guide disc (19) is provided with a screw hole and can be screwed onto a shaft journal (22) with a thread. The screw connection can be secured at the back using a lock nut (23). At the front, the guide disc (19) is secured against

a shaft collar (36) and tightened. A spacer disk (21) adapted to the desired axial position of the cellular wheel (6) can be inserted. This spacer disk (21) is preferably designed as a shim disk ground to a precise thickness.

The shaft (7) projects through the right-hand side cover (11) and the shaft bearing (9) arranged there, as well as through the housing attachment (25) adjoining the side cover (11). The guide disk (19) is supported on one side on this housing attachment (25), whereby a low-friction sliding disk (24) can be inserted. On the other side, the guide disk (19) also runs via an inserted sliding disk (24) on a corresponding support surface of the housing cover (26). The guide disk (19) is thus axially fixed between the housing parts (25, 26) and can rotate with the shaft (7). The housing cover (26) is essentially pot-shaped and tightly encloses the shaft journal (22) with the lock nut (23) and the guide disk (19).

To adjust the running clearance (37), the guide disk (19) is first adjusted against the support point on the housing attachment (25) by screwing the screw when the housing cover (26) is open. The desired axial position can be determined by measuring, taking into account the actual component tolerances. The widths of the side cover (11) and the housing attachment (25) can first be measured precisely, from which the required axial distance between the lateral vane edges (16) and the facing side of the guide disk (19) can be calculated and adjusted. The spacer disk (21) can also be manufactured precisely according to this measurement. On the other hand, depending on the housing design, the cell wheel (6) can also be centered visually or by measuring the

Column (37) in installation position possible. Here too, based on the measurement found, a spacer disk (21) with an appropriate thickness can be manufactured and then inserted.

The shaft bearings (9) are designed as plain bearings in the form of plug-in bushes which are inserted from the outside into the bearing opening of the side covers (10, 11) and are guided axially with an external collar. Ring-shaped shaft seals (34) are arranged on the other side facing the cellular wheel chamber (14). The shaft bearings (9) are preferably designed as lubricant-free bearings and consist, for example, of a low-friction plastic. Teflon bushes or the like can be used for this.

The side covers (10, 11) each have at least one housing pocket (31) in the area of the cellular wheel blades (15) and in particular in the area close to the shaft on the inside. This is preferably ring-shaped. The housing pocket (31) is open on one side towards the cellular wheel chamber (14) and on the other side towards the shaft (7). On the underside, the housing pockets (31) each have a downward and outward-facing drain (33) which opens into the outlet (4). Figures 1, 3 and 4 show this arrangement.

The cellular wheel blades (15) have a recessed recess (32) on both sides in the area of the housing pockets (31). This also shortens the length of the gap (37). The recess (32) can also at least partially cover the outlet (33) if the cellular wheel blades (15) are located at the bottom.

The shaft (7) with a drive pin (27) protrudes from the left side cover (10), which is connected to the drive pin (27) via a suitable rotationally locking and axially movable driver (28) with

a drive shaft (29) of the motor (5). This arrangement can be protectively surrounded by a bushing (38). This can have an access opening on the underside for inspection and maintenance purposes.

There is sufficient axial play between the drive pin (27) and the driver (28) for the axial positioning of the cellular wheel (6). The bushing (38) can be detachably connected to the drive (5) and the side cover (10) via screws or the like.

The rotary valve (1) can be completely dismantled for cleaning and maintenance purposes. Figure 5 shows this in the exploded view. After loosening the side covers (10,11) and the housing attachment,

(25) and the housing cover (26), the cell wheel (6) together with the guide disc (19) can be pulled out of the body part (2) through the side openings. The axial guide (18) and its adjusting device (20) can also be completely dismantled and cleaned.

Thanks to the shim (21), the parts can then be reassembled without having to re-calibrate the axial position of the cellular wheel (6) in the cellular wheel chamber (14).

In a variant of the embodiment of Figures 1 to 5 (not shown), the guide disk (19) can have a smooth through hole instead of the screw thread. It is then slidably placed on the shaft journal (22) and secured in its position on the shaft collar (36) or the spacer disk (21) with a nut and lock nut (23).

Furthermore, it is possible to provide an adapted collar on the guide disk (19) made to the exact size required instead of the separate spacer disk (21). Likewise, the guide disk (19) can also retain the shape shown and

- 10 -

their thickness can be adjusted exactly to the required size, which can be done by grinding or similar. In both cases, the disc adjustment means that the separate spacer disc (21) is not required. This simplifies handling and reduces the number of parts.

Further modifications to the embodiment shown are possible in various ways. Several cellular wheels (6) can be arranged in the housing (2) of the rotary valve (1). It is also possible to design the rotary wheel (6) itself differently. The recesses (32) can be omitted. The housing pockets (31) with the outlet (33) are also omitted. The shaft bearings can also be

(9) can be designed in any other suitable manner. Instead of the adjustable guide disk (19), the axial guide (18) can also have any other suitable guide element, e.g. a shaft collar fixedly arranged on the shaft (7). In the preferred embodiment, the guide disk (19) is arranged on only one side of the shaft (7) and is guided and clamped between the housing parts (25, 26) on both sides. Alternatively, two guide disks (19) or similar other guide elements can be present on both sides of the shaft (7), between which the axial positioning takes place.

The other design details of the rotary valve (1) with the housing and drive design are also variable.

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LIST OF REFERENCE SYMBOLS

1 Rotary valve 2 Housing 3 inlet 4 Outlet 5 Drive, engine &bgr; Cell wheel 7 Wave 8th Cell wheel axle 9 Shaft bearings 10 Housing part, side cover 11 Housing part, side cover 12 Fuselage part 13 Connection piece 14 Cell wheel chamber 15 Cell wheel blades 16 lateral wing edge 17 Chamber wall 18 Axial guidance 19 Guide disc 20 Adjusting device 21 Spacer, shim 22 Shaft journal, screw journal 23 Lock nut 24 Sliding disc 25 Housing part, housing attachment 26 Housing part, housing cover 27 Drive pin 28 Driving connection, driving 29 drive shaft 30 Screw, guide 31 Case bag 32 Recess 33 Sequence 34 poetry 35 Conveying direction _: .. ·:::.·: : : · : ·..·: : .· : : ·:
:..· · ·* . : : : : .· : : : : : : : :

·· -Si

-

3β wave collar

37 Running play, gap

38 Housing part, socket

Claims (13)

1. Cell wheel lock for bulk materials, in particular for pharmaceutical products, consisting of a housing with at least one rotatably mounted cell wheel with shaft and shaft bearings in a surrounding cell wheel chamber and with an axial guide, characterized in that the axial guide ( 18 ) is arranged on the shaft ( 7 ) of the cell wheel ( 6 ) separately from the shaft bearings ( 9 ), wherein the shaft bearings ( 9 ) are designed as radial bearings. 2. Cell wheel lock according to claim 1, characterized in that the axial guide ( 18 ) has an adjusting device ( 20 ) for the axial running clearance ( 37 ) of the cell wheel ( 6 ) in the cell wheel chamber ( 14 ). 3. Cell wheel lock according to claim 1 or 2, characterized in that the axial guide ( 18 ) has a guide disk ( 19 ) which is arranged on the shaft ( 7 ) of the cell wheel ( 6 ) and which is axially guided between two laterally arranged housing parts ( 25 , 26 ). 4. Cell wheel lock according to claim 1, 2 or 3, characterized in that the guide disc ( 19 ) is adjustably arranged on the shaft ( 7 ) and is preferably screwed onto a shaft journal ( 22 ) with a thread. 5. Cell wheel lock according to one of the preceding claims, characterized in that a spacer disk ( 21 ) adapted to the running clearance ( 37 ) is arranged between a contact collar ( 36 ) of the shaft journal ( 22 ) and the guide disk ( 19 ). 6. Rotary valve according to one of the preceding claims, characterized in that the guide disk ( 19 ) runs axially against two sliding disks ( 24 ) on the housing parts ( 25 , 26 ). 7. Rotary valve according to one of the preceding claims, characterized in that the housing parts ( 25 , 26 ) are designed as a housing attachment and housing cover which are detachably attached to the side of the housing ( 2 ) and which tightly encloses the shaft ( 7 ) and the axial guide ( 18 ) with the adjusting device ( 20 ). 8. Cell wheel lock according to one of the preceding claims, characterized in that the shaft ( 7 ) has at the other end a drive pin with an axially movable driving connection ( 28 ) to a drive ( 5 ). 9. Rotary valve according to one of the preceding claims, characterized in that the housing ( 2 ) has two side covers ( 10 , 11 ) with shaft bearings ( 9 ) and seals ( 34 ). 10. Rotary valve according to one of the preceding claims, characterized in that the housing attachment ( 25 ), the housing cover ( 26 ) and a side cover ( 11 ) are guided together and releasably connected to one another, preferably screwed ( 30 ). 11. Cell wheel lock according to one of the preceding claims, characterized in that the side covers ( 10 , 11 ) in the region of the cell wheel blades ( 15 ) have on the inside at least one housing pocket ( 31 ) which is open towards the cell wheel chamber ( 14 ) and the shaft ( 7 ) and which has a downward and outward-directed outlet ( 33 ). 12. Cell wheel lock according to one of the preceding claims, characterized in that the cell wheel blades ( 15 ) have a lateral recess ( 32 ) in the region of the housing pockets ( 31 ). 13. Cell wheel lock according to one of the preceding claims, characterized in that the shaft bearings ( 9 ) are designed as preferably lubricant-free plain bearings.