RU2813902C1 - Mixing tool for dry mixing and coating - Google Patents

Abstract

FIELD: mixing.

SUBSTANCE: present invention relates to a tool for dry mixing and coating of powder mixtures. Tool (1) for dry mixing and coating of powder mixtures comprises fastening rod (2) and disk-shaped element (4) with diameter d fixed on it with upper surface, lower surface and connecting upper and lower surfaces with circumferential surface, wherein disc-shaped element (4) has grooves extending parallel to the axis of the rod, wherein each groove has two grooves of wall (9, 10) extending from the circumferential surface to bottom (7), wherein tooth (5) is formed between two grooves, wherein disc-shaped element (4) has a main part and at least one wear-resistant element (6, 6') attached to the main part, wherein at least one section of each groove wall (9, 10) adjoining the circumferential surface is formed by said at least one wear-resistant element (6, 6'), note here that bottom surface has at least one swirler (8, 8') extending above bottom surface, note here that swirler (8, 8') is located closer to fastening rod (2) than groove bottom (7).

EFFECT: creation of a contamination-free tool suitable for dry mixing, dry dispersion and coating of powder mixtures.

14 cl, 4 dwg

Description

The present invention relates to an instrument for dry mixing and coating powder mixtures. Dry mixing involves mixing several dry and often powdery materials together. Coating can envelop larger powder particles during the dry mixing process by simultaneously depositing significantly smaller particles on the surface of larger particles. Alternatively, or in combination with smaller particles, liquids may be applied to the coarse powder in very small quantities to wet the surface of the particle as completely as possible.

From WO 2012/123441 A1 known are vortex tools for an intensive mixer for microgranulating wet mixtures of solids, in which there is a fastening rod and an approximately disk-shaped element with a diameter d fixed to this rod with an upper surface, a lower surface and a circumferential surface connecting the upper and lower surfaces, with In this case, the circumferential surface is equipped with a plurality of grooves running parallel to the axis of the rod, each groove having two groove walls extending from the circumferential surface to the bottom of the groove, so that a tooth is formed between each two adjacent grooves.

The term "circumferential surface" here means that the groove wall and the groove bottom are not part of the circumferential surface. Therefore, the circumferential surface is interrupted by introduced grooves. If the disk-shaped element is exactly circular, then the circumferential surface lies on the circumference of this disk-shaped element.

In the known vortex tool, a certain direction of rotation of the tool is set. Therefore, the groove wall leading in the direction of rotation is provided with a carbide element to reduce tool wear, in particular at the radially outer end.

Although tool abrasion is not desirable when microgranulating wet solid mixtures because it reduces yield, abrasion of the unprotected carbide element on the groove wall is inevitable. A small amount of abrasion product enters the mixture and inevitably mixes with the product, which, otherwise, does not cause problems in normal applications.

Consequently, the known tool is fundamentally not suitable for dry mixing and coating of powder mixtures, in particular when they must be as free from iron as possible, since due to its design it cannot be excluded that abrasion products from an iron tool can get into the mixture, which, however, Absolutely should be avoided in case of dry mixing that does not allow contamination. For example, when producing cathode material for an energy storage device, any contamination of the mixture, for example due to tool abrasion, must be avoided.

US Pat. No. 5,409,313 A1 also discloses a device for deagglomerating powder in a mixture of liquid and powder. This device contains a mixing tank, a mixing disk located in the mixing tank and a deflection plate. The disc has a plurality of composite teeth, which are mounted radially and can be removed along the periphery of the disc. Each compound tooth consists of a base on which is mounted a front plate, which preferably consists of a ceramic material such as tungsten carbide.

It is therefore an object of the present invention to provide a tool suitable for particularly contaminant-free dry mixing, dry dispersing and coating of powder mixtures.

According to the invention, this problem is achieved in that the disc-shaped element has a main part and at least one wear-resistant element attached to the main part, wherein at least one portion of each groove wall adjacent to the circumferential surface is formed by said at least one wear-resistant element, wherein the bottom surface has at least one swirler that protrudes above the bottom surface, the swirler being located closer to the fastening rod than the bottom of the groove.

According to the invention, not only the groove wall, which is oriented in the direction of rotation, but also the opposing groove wall and, preferably, also the circumferential surface at the radially outer end of the teeth are lined with the wear-resistant element. Experiments have shown that abrasion occurs mainly in areas of the groove wall that are adjacent to the circumferential surface.

Thanks to the use of wear-resistant elements on both groove walls, wear and abrasion can be significantly reduced and operation with minimal contamination can be ensured.

In principle, it is also possible for an entire tooth or even a group of teeth to be formed as a wear element. It is also possible for each tooth to be provided with a wear protection tip covering the tooth.

In all these cases, the portion of each groove wall adjacent to the circumferential surface is formed by at least one wear-resistant element. Therefore, several wear-resistant elements can be provided in one groove, which form at least sections of the opposite walls of the groove, or entire groups of teeth, or only individual teeth can be designed as wear-resistant elements. However, in each case it is ensured that at least one portion of each groove wall adjacent to the circumferential surface is formed from a wear-resistant material.

Wear-resistant material means any material that has increased wear resistance compared to the material of the main body.

The embodiment according to the invention has the advantage that the direction of rotation of the tool can be changed during operation in order to carry out the process with as little dust swirling as possible.

Preferably, the wear-resistant element consists of a hard alloy. However, other wear-resistant non-metallic materials, such as ceramics, can also be successfully used.

In another preferred embodiment of the invention, it is provided that both groove walls and preferably also the groove bottom are formed by said at least one wear-resistant element. In other words, not only the groove wall portion adjacent to the circumferential surface is provided with or formed by a wear-resistant element, but also the entire groove wall and preferably also the groove bottom. Moreover, the circumferential surface between the two grooves can be provided with or formed by a wear-resistant element. Thanks to this, abrasion can be further reduced.

In one preferred embodiment of the invention, the wear-resistant element consists of several parts (is composite).

It has been found that the groove bottom has a length extending from the first groove wall to the second groove wall that is at least 10%, preferably at least 25% of the groove wall length from the groove bottom to the circumferential surface.

In addition, at least 20%, preferably at least 50% of the length of the groove wall must be formed by said at least one wear-resistant element.

The V-shaped grooves shown in the above-cited document WO 2012/123441 in the dry mixing process have the disadvantage that under certain circumstances the components of the mixture, in particular in the case of cohesive starting materials, accumulate near the bottom of the groove and no longer participate in the process. mixing process. Thanks to the described design of the groove bottom, in particular in the region of the groove bottom, the groove is significantly larger, so that the risk of mixture components being retained at the groove bottom is significantly reduced.

To ensure effective mixing, the grooves should not be too small.

In one other preferred embodiment of the invention, the groove wall has a length extending from the circumferential surface to the bottom of the groove that is from 0.05 to 0.4 times, preferably from 0.1 to 0.3 times, and best of all from 0. 15 to 0.25 times the diameter d of the disc-shaped element.

According to the invention, it is provided that the lower surface has at least one swirler, which projects above the lower surface, wherein preferably several swirlers are provided, which are particularly preferably arranged with the same angular distance in the circumferential direction.

With the help of swirlers, the mixed material (mixture) that ends up under the disk is pushed outward and upward so that it can flow upward in the grooves. This prevents the components of the mixture from settling at the bottom of the container in which the instrument is installed and not participating in the further mixing process. Preferably, the swirler consists of a wear-resistant material, for example carbide or ceramic. The swirler may also consist of a hardened metal, such as hardened steel.

It has been found that at least four swirlers are needed to achieve effective mixing. It is best if there are even ten or more swirlers.

In another preferred embodiment of the invention, it is provided that the at least one swirler can be moved back and forth between two positions, wherein in the first position the swirler protrudes less from the bottom surface than in the second position.

In this case, the swirler at least in the second position can be fixed in such a way that during operation of the tool no accidental movement of the swirler between the first and second positions is possible. For example, the swirler may be length-adjustable such that movement between a first and second position is achieved by changing the length.

Alternatively, the length by which the swirler protrudes axially above the bottom surface of the disk-shaped element can be realized by having the swirler screwed onto the disk-shaped element and one or more washers positioned between the swirler and the disk-shaped element to vary said length.

Thanks to these measures, it is possible to position the swirler as close as possible to the surface of the container in which the tool is installed. Generally, it is desirable for at least one swirler, and preferably two swirlers, to be positioned close to the bottom of the container to clear the container of adhered material. Preferably, the distance between the lower edge of the swirler and the upper edge of the bottom of the container is from a few tenths of a millimeter to several millimeters, preferably from 0.2 mm to 5 mm. Then the remaining swirlers can be located at a significantly greater distance from the bottom surface of the container.

It may also be necessary to move the entire tool axially towards the bottom in order to separate the tool from the associated drive or centering flange. This is also possible thanks to the measures according to the invention, since in this case the swirlers can be moved from the second to the first position, so that a greater distance remains between the swirlers and the bottom of the container and the entire tool can be axially moved to disengage from the drive.

This can also be achieved due to the fact that the swirler has a threaded hole into which a screw passes through a through hole in the disk-shaped element to secure the swirler. If the tool is to be moved axially towards the bottom of the container, then the axially further protruding swirlers must be disconnected from the disc-shaped element and removed radially.

In one preferred embodiment of the invention, the swirler is also formed by a wear-resistant element. For example, the wear-resistant element may consist of a group of teeth and a integrally molded, for example soldered, swirl ring.

It has been found that the swirler is located closer to the fastening rod than the bottom of the groove, with preferably the distance between the fastening rod and the swirler being >50%, preferably >75%, and best of all 80 to 98% of the distance between the bottom of the groove and the fastening rod.

The present invention also relates to a device for dry mixing and coating powder mixtures, including a container and an instrument according to the invention located therein.

In this case, it is preferable that the container can rotate around an axis of the container, which is spaced from the axis of the fastening rod, and preferably the diameter d of the disk-shaped element is from 30 to 70% of the diameter of the container.

In another preferred embodiment of the invention, the tool is positioned within the container such that the shortest distance between the circumferential surface of the tool and the wall of the container is less than 10% of the diameter of the container.

Other advantages, features and applications of the invention will become apparent from the following description of the preferred embodiment and the accompanying drawings. Shown:

Fig. 1 is a perspective view of the first embodiment of the invention,

Fig. 2 - fragment of the first embodiment of the invention,

Fig. 3 is a fragmentary perspective view of a second embodiment of the invention,

Fig. 4 is a perspective view of a third embodiment of the invention.

In fig. 1 is a perspective view of a first embodiment of the invention.

The tool 1 according to the invention has a fastening rod 2 with a flange 3. Using the flange 3, the tool can be mounted on a drive (not shown) and rotated around the axis of the fastening rod 2.

At the end of the tool 1, facing away from the flange 3, there is a disk-shaped element 4, the axis of which coincides with the axis of the fastening rod 2.

The disc-shaped element has a top surface which is visible in FIG. 1, the lower surface, which is not visible in FIG. 1, and a circumferential surface connecting the upper and lower surfaces. It can be seen that the disc-shaped element has a plurality of teeth 5, which are formed by grooves running parallel to the axis of the rod. By introducing the grooves into the disc-shaped element, teeth 5 remain between the grooves. In the presented embodiment, both walls of the groove are lined with a wear-resistant element 6 made of hard alloy. In this embodiment, three parts of the wear-resistant element 6 are placed on each groove wall. Moreover, the radially outer parts of the wear-resistant element are located on the portion of the groove wall that is adjacent to the circumferential surface. All other wear-resistant elements on the groove wall are preferably adjacent directly to the bottom of the groove, to a part of the wear-resistant element positioned radially further outwards. The groove bottom 7 in this embodiment is not lined with a wear-resistant element.

However, it is also possible in this way to completely line the groove walls and the bottom, as well as the circumferential surface between two grooves, with a wear-resistant element or several wear-resistant elements in order to reduce abrasion. All other parts of the mixing tool that may come into contact with the material to be mixed, for example the fastening rod and the disc-shaped element, are in one preferred embodiment protected from wear by applying a wear-resistant layer. This layer can be obtained, for example, by surface hardening or coating. In this case, the coating may consist of a polymer material, for example, polyurethane, or be obtained by hardening the surface. Particularly preferred is a spray-on coating made of ceramic material or carbide. In this case, the thickness of the sprayed coating should, if possible, be at least 0.1 mm and especially preferably more than 0.4 mm. In addition, it is advantageous when the surface roughness of the coating is chosen such that a layer of product several layers thick adheres to it, thereby protecting the tool from abrasion and thus from wear.

On the lower surface of the disk-shaped element there are swirlers 8 and 8', which protrude above the lower surface. In the example shown, the swirler 8 is adjustable in height, that is, it is made in such a way that it can move back and forth between two positions, respectively, rearranged (adjusted) in its length, and the swirler 8 in the first position protrudes less above the bottom surface than in second position.

In fig. 2 shows an enlarged view of the disk-shaped element with swirlers according to FIG. 1. The swirler 8 is attached to the disk-shaped element 4 using a detachable screw connection 12. In order to achieve the smallest possible distance to the bottom of the container and compensate for manufacturing tolerances, one or more washers 11 are installed between the swirler 8 and the disk-shaped element 4. If manufacturing tolerances are very small, You can completely dispense with washers.

In fig. 3 and 4 show two other embodiments of the invention. In fig. 3 is a top perspective view of the tool, while FIG. Figure 4 shows a bottom view of the tool.

Where possible, the same reference numerals are used for like elements as in FIG. 1. Shown in FIG. 3 and fig. 4, the tool differs from the embodiment in FIG. 1, on the one hand, by the swirlers 8', which in this embodiment of the invention cannot be adjusted in height, and by the design of the parts 6' of the wear-resistant element.

In fig. 3 shows an embodiment of the invention in which the wear element 6' consists of individual teeth, for example entirely made of ceramic. The wear elements 6' are inserted in a form-fitting manner into corresponding recesses in the base plate by means of a tenon at the end of the wear element, so that they cannot move in the radial direction. Vertical movement of the wear member in the recess can be prevented, for example, by using a circular or annular cover plate on the top and bottom side of the base plate, partially or completely covering the recess. The end of the wear-resistant element opposite the tenon is a tooth 5 with groove walls 9 and 10 and groove bottom 7. The swirlers 8' can be attached to the wear elements 6'.

As can be seen in particular in FIG. 4, the wear-resistant wear element in this case consists of several wear-resistant element parts 6', each of which in turn forms seven tool teeth 5. In other words, in this embodiment, not only the groove bottom 7 and the groove walls 9, 10 are lined with a wear-resistant element, for example made of carbide, but also the entire tooth, that is, the entire part 6' of the wear-resistant element is made here, for example, of carbide . In fig. 4 shows the lower surface of said essentially disc-shaped element. It can also be seen that the swirlers 8' are attached to the wear element portions 6'.

List of reference items

1 Tool

2 Mounting rod

3 Flange

4 Disc-shaped element

5 Prongs

6, 6' Wear element

7 Groove bottom

8, 8' Swirlers

9 Groove wall

10 Groove wall

11 Washer

12 Screw connection

Claims (14)

1. A tool (1) for dry mixing and coating of powder mixtures, containing a fastening rod (2) and a disk-shaped element (4) with a diameter d fixed on it with an upper surface, a lower surface and a circumferential surface connecting the upper and lower surfaces, and the disk-shaped element ( 4) has grooves running parallel to the axis of the rod, and each groove has two grooves extending from the circumferential surface to the bottom (7) of the groove wall (9, 10), and between the two grooves a tooth (5) is formed, characterized in that the disk-shaped element (4 ) has a main part and at least one wear-resistant element (6, 6') attached to the main part, and at least one portion of each groove wall (9, 10) adjacent to the circumferential surface is formed by said at least one wear-resistant element (6 , 6'), and the lower surface has at least one swirler (8, 8'), which protrudes above the lower surface, and the swirler (8, 8') is located closer to the fastening rod (2) than the bottom (7) of the groove . 2. Tool (1) according to claim 1, characterized in that the wear-resistant element (6, 6') consists of a carbide or other wear-resistant non-metallic material. 3. Tool (1) according to claim 1 or 2, characterized in that both groove walls (9, 10) and preferably also the groove bottom (7) are formed by a wear-resistant element (6, 6'). 4. Tool (1) according to one of claims 1-3, characterized in that the wear-resistant element (6, 6') consists of several parts. 5. Tool (1) according to one of claims 1 to 4, characterized in that the bottom (7) of the groove has a length extending from the first wall (9) of the groove to the second wall (10) of the groove, which is at least 10%, preferably at least 25% of the groove wall length from the groove bottom (7) to the circumferential surface. 6. Tool (1) according to one of claims 1 to 5, characterized in that the wall (9, 10) of the groove has a length extending from the circumferential surface to the bottom (7) of the groove, which is from 0.05 to 0.4- multiple, preferably 0.1 to 0.3 times, preferably 0.15 to 0.25 times the diameter d. 7. Tool (1) according to one of claims 1 to 6, characterized in that several swirlers (8, 8') are provided, which are particularly preferably arranged with the same angular distance in the circumferential direction. 8. Tool (1) according to claim 1, characterized in that at least one swirler (8, 8') is configured to move back and forth between two positions or is designed to change in length, and in the first position the swirler ( 8, 8') protrudes less above the lower surface than in the second position. 9. Tool (1) according to one of claims 1 to 8, characterized in that the swirler (8, 8') is formed by a wear-resistant element (6, 6'). 10. Tool (1) according to one of claims 1 to 9, characterized in that the distance between the fastening rod (2) and the swirler (8, 8') is >50%, preferably >75%, best from 80 to 98 % of the distance between the bottom (7) of the groove and the fastening rod (2). 11. A device for dry mixing and coating of powder mixtures, containing a container and a tool (1) located in it according to one of claims 1 to 10. 12. The device according to claim 11, characterized in that the container is rotatable around the axis of the container, which is spaced from the axis of the fastening rod, and preferably the diameter d of the disk-shaped element (4) is from 30 to 70% of the diameter of the container. 13. Device according to claim 11 or 12, characterized in that the tool (1) is positioned inside the container in such a way that the shortest distance between the circumferential surface of the tool (1) and the wall of the container is less than 10% of the diameter of the container. 14. Device according to one of claims 11 to 13, characterized in that the distance between the lower edge of the swirler (8, 8') and the upper edge of the container bottom is from only a few tenths of a millimeter to several millimeters, preferably from 0.2 to 5 mm .

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