WO2008034517A1

WO2008034517A1 - Lamellar grinding disk

Info

Publication number: WO2008034517A1
Application number: PCT/EP2007/007701
Authority: WO
Inventors: Gerd Eisenblätter
Original assignee: Gerd Eisenblätter Gmbh
Priority date: 2006-09-19
Filing date: 2007-09-04
Publication date: 2008-03-27
Also published as: DE102006043989A1

Abstract

Disclosed is a lamellar grinding disk (10), with a rotationally symmetric support disk (11) on which ring-shaped, laminar lamellae (12) made of abrasive material are distributed around the perimeter and are each affixed on one edge thereof in such a way that said lamellae extend from an inner area of the support disk to an outer area, and the outer ends thereof project beyond the perimeter of the support disk. The planes of the lamellae form a solid, acute angle with the plane of the support disk. In addition, the lamellae are arranged such that in the resting state said lamellae are separated at the outer ends (14) thereof from each other in such a manner that said lamellae yield elastically under minimal pressure on the peripheral edge (15), and/or on the side (16) which faces away from the support disk, until the outer ends of several neighboring lamellae come into position on top of each other and thereby together form a rigid overlap (17).

Description

FLAP DISC

The invention relates to a lamellar grinding wheel, comprising a rotationally symmetrical carrier plate, on soft annular distributed around the circumference of flat slats of Schleifmateriai at each of its edges are adhered so that they extend from an inner region of the carrier plate to an outer region and their outer ends over the circumference of the support plate, wherein the planes of the slats with the plane of the support plate each include a fixed, acute angle.

Flap discs are known from the prior art, wherein on a carrier plate grinding lamellae are arranged like a fan around the circumference of the carrier plate. In such conventional flap discs each overlap several fins. Each louver is supported on one side by a plurality of adjacent lamellae and is therefore spaced on this side of the carrier plate. On the opposite side edge, however, the slats lie on the carrier plate. As a result, the slats are tilted at a relatively shallow angle relative to the carrier plate. Such flap discs are preferably used in Wiśkelschleifgeräten for the removal of welds and Craten. The working range of a conventional flap disc is mainly in the outer peripheral region. However, the work surface is formed by the side facing away from the carrier plates sides of the slats and is substantially parallel to the carrier plate. In a grinding operation, therefore, a conventional flap disc must be placed on the Werbtückoberfläche at a relatively shallow angle. Surfaces in corners and edges are therefore often inaccessible. Welds and ridges in edges are therefore difficult to machine with a conventional flap disc. In particular, so that no soft sanding transitions can be achieved. Against this background, it is an object of the invention to improve the known grinding wheels in such a way that edges can be processed better.

A slotted grinding wheel according to the invention thus comprises a rotationally symmetrical carrier plate, on which are distributed annularly around the circumference flat slats of abrasive material on each of its edges are adhered to that of extend an inner region of the carrier plate to an outer region and project beyond its outer ends over the circumference of the carrier plate. As a result, the diameter of the lamellar grinding wheel is increased in comparison to the carrier plate and the outer lamella ends form an outer circumferential edge. The planes of the slats form with the plane of the carrier plate each a fixed acute angle which is greater than 0 ° and less than 90 °. If the plane of the carrier plate and the plane of the grinding lamella enclose an angle of less than 90 ° and the lamellae have a uniform thickness, it is naturally possible to measure an angle of more than 90 ° between the rear side of the lamella and the carrier plate. This rear side of the slats is referred to below as the carrier plate side facing away.

According to the invention, the slats are also arranged so that they are spatially separated at their outer ends on the outer peripheral edge at rest in such a way that they yield elastically at low pressure on the outer peripheral edge or on their side facing away from the carrier plate. In the case of stronger pressure, according to the invention, they only give way until the outer ends of a plurality of adjacent lamellae come to rest on one another, thereby supporting one another, and thus together form a rigid projection. Due to the increased pressure and the contact of the individual adjacent lamellae, the lamellae are compacted into a solid package and then resemble in their stiffness of a compressed conventional flap disc.

This construction allows in operation a dual function of the disk grinding wheel according to the invention. The pressure on the slats is regulated by the contact pressure with which a rotating grinding wheel is pressed onto a workpiece. At a low contact pressure of the disc on a workpiece surface, a low material removal can be achieved. The flap grinding wheel according to the invention is then suitable, for example, for finely deburring and for soft grinding transitions. With stronger grinding pressure, the lamellae stiffen each other and a hard contact with the workpiece surface occurs, so that a larger material removal results. can be enough. With the disk grinding wheel according to the invention, therefore, two different operations can be performed, which makes time consuming ige disk change unnecessary.

In addition, the working surface of the lamellar grinding wheel is displaced in the direction of the outer lateral surface with stronger contact pressure by the deformation of the lamellae relative to a conventional flapper disk. This outer circumferential surface is formed by the outer ends of the bent blades. This makes it possible for the grinding wheel according to the invention to be placed on a work surface even at a very steep angle. This makes it possible to grind with the peripheral edge or the cylinder jacket surface, which is formed by the outer fin ends, even in otherwise inaccessible corners.

To drive the vane grinding wheel with a drive machine, the carrier plate in the center on a passage opening for receiving a drive shaft. The passage opening may be simply cylindrical, for example 15/16 "or 22.2 mm in diameter Alternatively, the passage opening may also have an internal thread, for example an M10, M14 or 5/8". For grinding in edges, it is also advantageous if the carrier plate is made flat.

The slats may be arranged so that they touch each other at their ends facing the center of the carrier plate. However, according to the annular arrangement, the outer ends protruding beyond the carrier plate are spaced apart from each other. In this case, the lamellae should be arranged so tightly that at local pressure on individual lamellae, several lamellae come into contact with each other and support each other so that the supernatant of the lamellar ends on the support plate is rigid at this point. Although the outer fin ends must therefore be spaced apart from each other so that they can deform, but they must not be too far apart from each other, so that each can support a plurality of fins. If the gap is too large, so the blades can not compact enough to form a package even with strong contact pressure and would therefore only continue to act springy. The measured at the outer peripheral edge gap between two outer fin ends should therefore not be greater than 2 mm as possible.

In a preferred embodiment of the invention, therefore, corresponds to the distance between the outer ends of two adjacent slats averaged to two to three times the slat thickness. The distance here is the sum of the lamella thickness and the space between the lamellae. The averaging refers to the entire disc, whereby, of course, the variations in the distances should be as low as possible. In a particularly preferred variant, the distance between the outer ends of two adjacent slats corresponds in each case between 2.5 and 3.5 mm. Accordingly, and depending on the size of the disc, the number of slats and the intermediate angle, which include adjacent slats together, determined.

In principle, the lamellae can be arranged radially or tangentially, that is, the extensions of the middle straight line through each lamella can cut in the center of the disc or each tilted at an angle to the radial direction. According to a preferred embodiment, the edges of the lamellae, to which they are adhered to the carrier plate, extend along a radius of the carrier plate. This means that the corresponding edges of all slats run towards the center of the carrier plate.

In the following table, for example, favorable slat numbers for different disc diameters of 100 mm to 178 mm are given. The diameter refers to the total diameter of the disc equipped with lamellae. In comparison, the diameter of the carrier plate is smaller by twice the amount of the supernatant. For example, the following information is favorable for slats with a thickness of 1.5 mm.

With an overall diameter of the disc of 125 mm and a mean distance between the outer lamella ends of about 3 mm, for example, 130 fins can be mounted on the disc. Distributed over 360 °, two slats each enclose an intermediate angle of 2.8 ° with each other.

In a preferred embodiment, the overall diameter of the flap grinding wheel is between 120 and 130 mm. The number of lamellae is according to preferential between 120 and 140 slats. The slats have a preferred length of 30 to 35 mm.

In another preferred variant, the lamellar grinding wheel has a diameter between 170 mm and 185 mm and comprises 160 to 220 lamellae. The length of the lamellae in this larger variant of the lamellar grinding wheel is preferably between 35 and 45 mm.

According to the invention, the fin ends over the outer peripheral edge of the carrier plate and form a supernatant. Preferably, the radius of the disc is increased by this projection by at least 10 mm over the radius of the carrier plate. In the larger version of the flap grinding wheels mentioned above, even an even larger projection of at least 15 mm is favorable. The supernatant should, however, expediently not be more than 20 mm, since otherwise possibly the stability of the supernatant wears off.

The width of the slats is preferably between 13 and 20 mm. Compared to a conventional flap disc, the slats are placed steeper relative to the plane of the carrier plate and include a larger angle with this.

In a preferred embodiment of the invention the flap grinding wheel is the angle, which includes slats and support plates, between 40 ° and 70 °. Due to the tilting of the slats relative to the support plate, the height of the slat ring above the support plate is less than the slat width, for example, the height is 10 mm with a slat width of 13 mm and a tilt angle of 50 °.

The slats are strip-shaped and may consist of abrasive cloth or sandpaper. In a preferred embodiment, the lamellae consist of an abrasive cloth, which is formed by a tissue occupied by abrasive grain. Suitable is a blended fabric of cotton and polyester or a hemp / flax / sisal knitted fabric, which withstands the high mechanical loads occurring during operation. The lamellae are designed to be abrasive at least on their side facing away from the carrier plate. Preference is given to fins with zirconium corundum scattering. Depending on the grain size and strength of the base such as fabric or paper, the lamellae have a certain thickness and also a bending stiffness. The grain size of the abrasive flaps is preferably between 40 and 100, more preferably between 40 and 60.

Thus, the slats can yield to pressure while the splice does not break, the adhesive, with which the slats are adhered to the carrier plate, preferably one Residual elasticity. For example, polyurethane adhesive and cold or hot glue are suitable. A residual elasticity also allows an additional damping effect at the junction between the slats and carrier plate.

To produce a flap grinding wheel according to the invention, it is advantageous if the carrier plate has a stop ring in the form of an annular elevation on the surface, which defines the inner edge of the slats. The inner edges of the slats are then from the outside of this stop ring. Also, between the stop ring and the inner edges of the slats, an adhesive connection may be beneficial;

In a preferred embodiment, the stop ring for better anchoring of the adhesive also on its outer lateral surface on an annular undercut. When gluing the carrier plate with the lamellae so the adhesive can flow into this undercut and therefore provide better anchoring. Favorable for a good grip of the slats on the support plate, it is also when the support surface for the slats on the support plate has a structure that prevents slippage of the slats. Particularly suitable here is an O berfläche with pyramidal elevations, on the one hand provide a higher adhesive surface and on the other hand prevent caused by vibration slipping of the slats.

The carrier plate is preferably made of a spanbaren material that can be easily trimmed. Such a material is for example a plastic, such as ABS, or a plastic reinforced with natural fibers. Particularly suitable here is a hemp fiber-polypropylene mixture. Such a carrier plate can be produced for example by injection molding of granules, wherein the granules of hemp fibers and a binder.

In the following, the invention will be explained with reference to the embodiment shown in Figures 1 to 6 on. They show schematically:

Figure 1: a lamellar grinding disc in plan view of the top with lamellae;

FIG. 2: a lamellar grinding disk in side view;

FIG. 3: a partial view of a flap grinding wheel in plan view;

FIG. 4 shows a side view of a lamellar grinding wheel with elastically bent lamellae;

FIG. 5 shows a disk grinding disk in vertical section through the disk center; and

Figure 6: the use of a lamellar grinding wheel for deburring in an edge. A disk grinding wheel 10 comprises a carrier plate 11 and arranged around the circumference slats 12. The carrier plate 11 has in the center a passage opening 21 for mounting on a drive shaft 22 of a drive machine. The passage opening 21 may be equipped with various fastening devices for non-rotatable mounting on the drive shaft 22. The carrier plate 11 also has a stop ring 18, on which the fins 12 are present with their inner ends 19. The fins 12 are evenly distributed around the circumference of the carrier plate 11. They are attached with a side edge to the carrier plate and close at this adhesive edge an angle α with the carrier plate. This angle α is the same for all slats. The different angles shown in the figures indicate only the perspective view. The lamellae 12 are arranged on the carrier plate so that their central longitudinal axis is aligned along a radius of the carrier plate. The adhesive edge of each blade therefore does not coincide with a radius of the carrier plate. The slats abut with their inner end 19 ah a stop ring 18 and are thereby defined in its radial position. The outer end 14 of the slats projects beyond the circumference of the carrier plate and forms a projection 17.

When pressure on the blade ends in the circumferential direction, indicated by the arrow 15 in Figure 4, the lamella give elastically until they come into contact with the adjacent blade and these also deform elastically. The same effect is achieved by pressure on the side facing away from the carrier plate top of the lamella towards the carrier plate indicated by arrow 16 in Figure 4. The pressure causes several adjacent lamellae create each other, thereby supporting each other and in this way a form a rigid supernatant. This overlap and attachment of the outer ends 14 of the abrasive flaps 12 forms a hard abrasive surface. The grinding surface is displaced to the cylinder jacket surface formed by the lamella ends 14.

At their inner ends 19, the individual fins 12 are attached to the stop ring 18. The stop ring 18 has an annular undercut 20. In this undercut 20 adhesive for the connection of lamellae 12 and carrier plate 11 can flow in during production and in this way provide better anchoring.

To remove welds 23 in edges, the lamellar grinding wheel 10 can be set at a steep angle to the degree, since under strong pressure, the cylinder jacket surface of the vane grinding wheel 10 forms an abrasive surface.

Claims

1. lamellar grinding wheel (10), comprising a rotationally symmetrical carrier plate (11) on which annularly distributed around the circumference, flat lamellae (12) of abrasive material are each attached to one of its edges so that they from an inner region of the carrier tersers (11) extend to an outer portion and their outer ends over the circumference of the support plate (11) protrude, wherein the planes of the lamellae (12) with the plane of the support plate (11) each include a fixed acute angle (α), characterized characterized in that the lamellae (12) are arranged so that they are spatially separated at their outer ends (14) at rest in such a way that they at low pressure on the peripheral edge (15) and / or on the carrier plate deflected side (16) elastically yield and only give so much pressure under stronger pressure until the outer ends (14) of several adjacent lamellae (12) come to rest on each other, support each other and together form a rigid supernatant (17).

2. sipe grinding wheel (10) according to claim 1, characterized in that the average distance of the outer ends (14) in each case two adjacent lamellae (12) corresponds to two to three times the thickness of the lamellae (12).

3. sipe grinding wheel according to one of the preceding claims, characterized in that the outer ends (14) in each case two adjacent lamellae (12) have an average distance between 2.5 and 3.5 mm.

4. sipe grinding wheel (10) according to one of the preceding claims, characterized in that the edges (13) on which each of the individual slats (12) are adhered to the carrier plate (11) are radially aligned on the carrier plate (11).

5. lamellar grinding wheel (10) according to one of the preceding claims, characterized in that it has a diameter of 120 mm to 130 mm and the number of lamellae (12) is between 120 and 140.

6. lamellar grinding wheel (10) according to claim 5, characterized in that the lamellae (12) are between 30 mm and 35 mm long.

7. lamellar grinding wheel (10) according to one of claims 1 to 4, characterized in that it has an overall diameter of 170 mm to 185 mm and the number of lamellae (12) is between 160 and 220.

8. lamellar grinding wheel (10) according to claim 7, characterized in that the lamellae (12) are between 35 mm and 45 mm long.

9. lamellar grinding wheel (10) according to any one of the preceding claims, characterized in that the supernatant (17) formed by the Lame'len (12) beyond the circumference of the carrier plate (H) is at least 10 mm.

10. lamellar grinding wheel (10) according to any one of the preceding claims, characterized in that the lamellae (12) are between 13 mm and 20 mm wide.

11. vane grinding wheel according to one of the preceding claims, characterized in that the blades are tilted at an angle of 40 ° to 70 ° relative to the carrier plate.

12. The flap wheel (10) according to one of the preceding claims, characterized in that the abrasive material is an abrasive cloth consisting of an abrasive grain-filled fabric.

13. Lamellar grinding wheel (10) according to one of the preceding claims, characterized in that the grain size of the abrasive material is between 40 and 100, particularly preferably between 40 and 60.

14. lamellar grinding wheel (10) according to one of the preceding claims, characterized in that the adhesive with which the lamellae (12) are adhered to the carrier plate (11) has a residual elasticity.

15. lamellar grinding wheel (10) according to one of the preceding claims, characterized in that the carrier plate (11) has a stop ring (18) at the outer edge of the slats (12) with its inner edge (19) are present.

16 slat grinding wheel (10) according to claim 15, characterized in that the stop ring (18) has an annular undercut (20), in which the adhesive for fixing the slats (12) is anchored.

17. vane grinding wheel (10) according to one of the preceding claims, characterized in that the carrier plate (11) is made of plastic.

18. Lamellenschleifscheibed O) according to one of the preceding claims, characterized in that the carrier plate (11) is made of reinforced with natural fibers plastic.