EP4306264A1 - Radial brush for grinding and polishing purposes - Google Patents

Abstract

The invention relates to a disc-like radial brush for grinding or polishing purposes, with a plate-shaped central body (1) having two side surfaces (5, 9), which has an essentially central opening (4), and with a plurality of bristles (2, 3). , which extend away from the central body (1) in the radial direction. In order to ensure that such radial brushes can also be assembled into brush rollers, it is proposed that the central body (1) has projections (7) on at least one of the side surfaces (5) and corresponding receptacles (8) on the other side surface (9). is provided. This means that corresponding radial brushes can be used in brush rollers without individual radial brushes slipping or being compressed too strongly and thus deformed to avoid slipping.

Description

The invention relates to a disc-like radial brush for grinding or polishing purposes, with a plate-shaped central body having two side surfaces, which has a substantially central opening, and with a plurality of bristles which extend away from the central body in the radial direction.

Radial brushes of this type are generally known. They are used in jewelry production or in the production of dentures. The radial brush with the central opening is placed on a spindle that can rotate at high speed and is secured on it to prevent it from slipping or slipping. Such spindles are also referred to as mandrels and, to secure the radial brushes, have a collar at their end that projects in the radial direction and is connected to them in a rotation-proof manner and is fixed in the axial direction. A flange washer is then attached to the spindle at the axial end, in particular by screwing with a thread present there, whereby the radial brush is usually fixed between the projecting collar and the flange washer by clamping.

The bristles of the radial brushes then essentially extend radially away from the centrally arranged spindle in a plane normal to the central axis of the spindle, whereby they can have both a straight and a curved course within this plane.

In order to create a wider brush roller, several of the disk-like radial brushes are placed next to each other on the spindle with their essentially central openings and are placed next to each other by means of the Flange washer clamped together and against the collar. This creates an essentially cylindrical brush roller.

When pressing this cylindrical brush roller in a radial direction onto a workpiece to be polished, the rotation of the spindle must be transmitted in the same way to all elements of the brush roller, i.e. to all radial brushes seated on the spindle, so that individual ones are not arranged, in particular in the middle of the brush roller Radial brushes are braked by the forces that occur during polishing and thus slowed down in their rotation. This would reduce the polishing rate of these individual, braked radial brushes.

A workpiece that is processed with a brush roller with radial brushes that slip through, i.e. do not rotate completely, does not have a flat shape, but rather a convex shape.

In order to prevent the rotation speed from slowing down or slipping of individual radial brushes and the associated reduced sectional reduction in polishing performance, the contact pressure forces acting in the axial direction between the individual radial brushes are increased, preferably by bringing the flange disk on the spindle a little closer to the collar , in particular screwed on, which is present on the spindle. This means that the radial brushes are pressed more strongly against each other in the axial direction of the spindle.

However, this has the disadvantage that with relatively narrow brush rollers, the bristles extending away from these central bodies in the radial direction on the end faces of the brush roller bend a little bit outwards in the axial direction due to the compression of the plate-shaped central bodies. This means that narrow brush rollers in particular do not have a cylindrical shape, but are slightly barrel-shaped.

A workpiece that is processed with such a brush roller is then no longer flat, but due to the no longer cylindrical, but rather slightly convex or cambered or barrel-shaped outer contour of the brush roller has a correspondingly concave shape.

It is therefore not easy to produce an optimal brush roller by assembling several disc-like radial brushes on a spindle and then axially clamping them. Corresponding brush rollers are often tested several times when they are put together to determine whether the axial contact force between the individual radial brushes is sufficient to prevent individual radial brushes arranged in the middle of a brush roller from slowing down when the brush roller is actually in use, but on the other hand is not too great, which would lead to the barrel-shaped deformation of the brush roller described above. This repeated testing can be very time-consuming and requires a lot of experience to achieve the desired result.

The object of the present invention is therefore to further develop a radial brush as stated above in such a way that a cylindrical brush roller, with which flat surfaces can be produced under a wide variety of conditions, can be easily produced from these radial brushes.

This object is achieved according to the invention by a radial brush with the features of the attached main claim.

Accordingly, a radial brush, as stated at the outset, has a plate-shaped central body having two side surfaces, which has a substantially central opening, and a plurality of bristles which extend away from the central body in the radial direction, the central body having projections and on at least one of the side surfaces on the other side surface is provided with corresponding receptacles in the form of recesses.

Further advantageous training can be found in the subclaims.

The invention has the advantage that when at least two radial brushes are arranged on a spindle and next to each other, the projections on the one side surface of the first radial brush engages in the receptacles of the other side surface of the second radial brush. This means that not only a force or frictional connection can be generated in the circumferential direction between the two radial brushes, as in the prior art, but also a positive connection is achieved between the radial brushes arranged next to one another.

This has the further advantage that it is also easier to use lubricants or coolants in the grinding process. The use of such means changes the friction that exists between the radial brushes arranged next to one another on a spindle and which is used in the previously known devices for transmitting the rotation of radial brushes lined up next to one another on the spindle. Due to the positive connection now created between adjacent radial brushes, the rotation transmission is independent of the aforementioned friction.

In a preferred embodiment of the invention, the projections on one side of the radial brush and the receptacles on the other side of the radial brush are arranged offset from one another in the circumferential direction.

This ensures that radial brushes arranged next to one another in the axial direction only sit next to one another in correspondingly offset relative positions, namely slightly rotated relative to one another in the circumferential direction. This allows the relative positions of the bristles of radial brushes arranged next to one another to be arranged with a predetermined offset from one another in the circumferential direction.

In a particularly preferred embodiment of the invention, the projections and the receptacles are designed in a substantially elongated shape.

This is advantageous because this elongated shape facilitates the production of the radial brushes according to the invention. Radial brushes according to the invention are manufactured using an injection molding process. This can be used for production The material used in the mold molds the elongated shape of projections and receptacles particularly well.

The projections and receptacles preferably also run in the radial direction. On the one hand, this is advantageous for production and, on the other hand, the transmission of forces in the circumferential direction is further improved, which is essential for the (co-)rotation of the individual radial brushes within a brush roller.

It should be mentioned that in the radial brushes according to the invention, the plate-shaped central body and the bristles extending in the radial direction are made in one piece with one another and in particular from a thermoplastic polyurethane ("TPU") material containing abrasive particles.

As mentioned, to form a brush roller, several radial brushes are placed side by side on a spindle. This runs through the central opening provided for this purpose on the central body of the radial brush. The projections and receptacles lie, in particular, outside an annular area surrounding this central opening.

In this ring area, a flange disk described at the beginning can come into contact with a radial brush at the end of the brush roll, as is conventional at one end of a brush roller, or a terminal radial brush at the other end of the brush roll comes into contact via this ring area with a brush which projects in the radial direction from the spindle Collar. The spindles previously used can therefore also be used with the radial brushes according to the invention.

Preferably, the projections on one side of the radial brush can also be combined into groups. This makes it possible to use these projections to generate a type of bar code that can be used to identify different radial brushes. For example, radial brushes have differences in their hardness, their Temperature resistance or the grain size of the abrasive particles used in them.

• Fig. 1 die Aufsicht einer erfindungsgemäßen Radialbürste;
• Fig. 2 die Unteransicht einer Radialbürste gemäß Fig. 1;
• Fig. 3 die Seitenansicht einer Spindel mit darauf sitzenden Radialbürsten;
• Fig. 4 die Aufsicht einer Spindel gemäß Fig. 3.

Further advantages and features of the invention result from the following description of an exemplary embodiment. This shows:

• Fig. 1 the top view of a radial brush according to the invention;
• Fig. 2 the bottom view of a radial brush according to Fig. 1 ;
• Fig. 3 the side view of a spindle with radial brushes sitting on it;
• Fig. 4 the supervision of a spindle Fig. 3 .

Fig. 1 shows the top view of a radial brush according to the invention. One can see a central body 1 and a plurality of bristles 2, 3 which extend away from the central body 1 in the radial direction. The bristles 2, 3 shown here have a curved shape and run with a curvature counter to the direction of rotation. The bristles 2, 3 lie in planes that are parallel to a central plane of the central body 1.

In its center, the central body 1 has a round, central opening 4 through which the radial brush is placed on a rotatable spindle, which will be explained further below.

The central opening 4 is on the in the Figure 1 visible first side surface 5, which is shown in plan view, surrounded by a circular ring area 6, which is essentially flat.

Outside of this ring area 6, the first side surface 5 is provided with elongated projections 7 which are essentially oriented in the radial direction. These protrude with a substantially triangular cross section in the axial direction from the plane of the first side surface 5.

This triangular cross section is essentially congruent with the cross section of corresponding elongated receptacles 8, which are introduced on the other side surfaces 9 of the central body 1 and thus also have a substantially triangular cross section. The other Side surface 9 is in the Fig. 2 in the bottom view of a radial brush Fig. 1 shown.

When two radial brushes are arranged side by side, in which one side surface of the first radial brush comes into contact with the other side surface of the second radial brush, the projections 7 of one radial brush engage in the congruent receptacles 8 of the other radial brush and these two radial brushes are thereby positively connected to each other in the circumferential direction.

In the Figure 1 It can also be seen that the central body 1 merges integrally into bristles 2 which are aligned with the surface of the first side surfaces 5 on its first side surfaces 5 lying above. On the other side surface 9, the central body 1 merges in one piece into bristles 3 which are aligned with the top of the other side surface 9. The bristles 2, which are assigned to the first side surface 5, and the bristles 3, which are assigned to the other side surface 9, each have a thickness that corresponds approximately to half the thickness of the radial brush and are therefore located on both sides of the central plane of the central body and thus the Radial brush.

There are gaps in the circumferential direction between the bristles 2, which, as explained, are assigned to the first side surfaces 5. The bristles 3, which are assigned to the other side surface 9, lie essentially in the middle of these gaps on the other side of the central plane. Seen from the side, a radial brush has a dense sequence of bristles 2, 3 in the circumferential direction.

In the Figure 3 shows how two radial brushes are assembled together to form a brush roller: You can see a spindle 10, which is also referred to as a mandrel, in the side view. This spindle carries a collar 11 which is integrally connected to it in this exemplary embodiment and which projects in the radial direction.

A first radial brush 12 with an annular region 16 comes into contact with this collar 11 when its central opening 4 opens the spindle 10 is attached. This annular area 16 surrounds the central opening 4 on the other side surfaces 9 of the radial brush 12. The annular area 16 is flat in order to be able to come into flat contact with the collar 11 and essentially extends to the radially inner edges of the outside Recordings 8.

A second radial brush 13 is then placed with its central opening 4 on the spindle 10, with the first side surface 5 of the first radial brush 12 coming into contact with the other side surface 9 of the second radial brush 13. The grip on the first side surface 5 of the The projections 7 provided for the first radial brush now fit positively into the receptacles 8 corresponding to them on the other side surface 9 of the second radial brush 13, as described.

Now it is the case that the radial extent of the projections 7 is precisely aligned with the gaps between the bristles 2 assigned to the first side surface 5.

Furthermore, the radial extent of the receptacles 8 is precisely aligned with the gaps between the bristles 3 assigned to the other side surface 9.

This also ensures that when the projections 7, which are arranged on the first side surface of the first radial brush 12, engage in the receptacles 8, which are arranged on the other side surface 9 of the second radial brush 13, the bristles 2, into which the central body the first radial brush 12 merges on its first side surface 5, lie exactly in the gaps that can be found between the bristles 3, into which the central body of the second radial brush 13 merges on its other side surface 9.

This is repeated if more than two radial brushes are assembled on a spindle to form a wider brush roller.

This means that even with several radial brushes assembled side by side to form a brush roller, a uniform distribution of the bristles is achieved both in the circumferential direction and in the axial direction.

In order to clamp the first radial brush 12 and the second radial brush 13 together, the first radial brush 12 is first threaded onto the spindle 10 with its central opening 4. It comes with its annular area 16 into contact with the surface facing it of the collar 11 arranged on the spindle 10. The second radial brush 13 is then threaded with its central opening 4 onto the spindle 10 and finally the in the Figure 3 A flange disk 14 is screwed onto the right end of the spindle 10, which comes into contact with the annular area 6 on the first side surface 5 of the second radial brush 13. The annular area 6 runs around the central opening 4.

This flange washer 14 is designed like a screw and therefore has one in the for screwing on Figure 4 visible screw slot 15.

By screwing on, the flange disk 14 is pressed against the second radial brush 13, this against the first radial brush 12 and this in turn against the collar 11 on the spindle 10.

Due to the projections 7 and receptacles 8 connecting to one another when the first radial brush 12 is compressed with the second radial brush 13, it is no longer necessary to tighten the flange disk 14 extremely tightly on the end of the spindle 10 in order to prevent friction between the radial brushes 12. 13 to achieve a rotationally fixed connection of several adjacent radial brushes. This is particularly relevant when more than two radial brushes are combined to form a longer brush roll.

This limited tightening also prevents the central bodies of radial brushes 12, 13 arranged next to one another from being unnecessarily compressed, which is the case at the ends in the axial direction arranged radial brushes would lead to the bristles bending outwards in the axial direction, so that the peripheral surface of a corresponding brush roller composed of several radial brushes would be barrel-shaped. It would therefore not be suitable for creating a flat surface.

At the same time, the interconnecting projections 7 and receptacles 8 ensure that all radial brushes within such a brush roller are connected to one another in a rotationally fixed manner and that individual radial brushes, in particular in the central area of the brush roller, cannot be braked and their rotation slowed down when in use the brush roller is pressed against a workpiece.

In the Fig. 1 It can also be seen that the individual projections 7 are grouped together, in the example shown here in three groups of four projections. On the one hand, tool construction can of course be simplified by omitting individual projections.

With such groups of projections it is also possible to code the radial brushes. In this way, a marking can be attached to the radial brush, which can be used, for example, to distinguish what hardness or temperature resistance a radial brush has or what grain size the abrasive particles used for the radial brush have. If necessary, the thickness, outer diameter or diameter of the central opening or comparable properties of the radial brush that are relevant to a user can also be coded.

Overall, the radial brush according to the invention provides a product that brings significant advantages in use.

Reference symbol list

1

Central body

2

bristles

3

bristles

4

central opening

5

first side surface

6

Ring area

7

Projections

8th

Recordings

9

other side surface

10

spindle

11

collar

12

first radial brush

13

second radial brush

14

flange washer

15

screw slot

16

annular area

Claims (6)

Disc-like radial brush for grinding or polishing purposes with a plate-shaped central body (1) having two side surfaces (5, 9), which has a substantially central opening (4), and with a plurality of bristles (2, 3), which are from extend away from the central body (1) in the radial direction,
characterized,
that the central body (1) is provided with projections (7) on at least one of the side surfaces (5) and with corresponding receptacles (8) on the other side surface (9). Radial brush according to claim 1,
characterized,
that the projections (7) on one side surface (5) and the receptacles (8) on the other side surface (9) are arranged offset from one another in the circumferential direction. Radial brush according to one of the preceding claims,
characterized,
that the projections (7) and the receptacles (8) are designed in a substantially elongated shape. Radial brush according to claim 3,
characterized,
that the projections (7) and the receptacles (8) run in a substantially radial direction. Radial brush according to one of the preceding claims,
characterized,
that the projections (7) and the receptacles (8) lie outside an annular area (6, 16) surrounding the central opening (4). Radial brush according to one of the preceding claims,
characterized,
that the projections (7) on one side surface (5) are combined in groups.

Images