DE1963872A1 - Cutting knife for hard materials - Google Patents

Description

Dr. Ing. E. BERKENFELD · Dipl.-Ing. H. BERKENFELD, patent attorneys

lawyers, Cologne

Attachment file number

to enter -j Q. December 69 Sch // Nam.d. Note: Shirley I. Weiss

Cutting knife for hard materials.

In cutting very hard materials annular cutting knives are used, the g is a progressively smaller core have thick, in order to reduce the cutting waste of the expensive hard material. However, a number of problems arise with thinner cutting blades. For example, there is an increased tendency to encounter damage to the hard material disks. This in turn requires later sole grinding processes and a corresponding reduction in the thickness of the slices, which must be accepted when the original slices are cut.

Likewise, the load on the cutting knives is considerable, resulting in deformation of the knife, destruction of the knife, damage to the material to be cut, and reduced performance of the cutting machine. {

One object of the invention therefore consists in the design of improved ring-shaped cutting knives which have thin metal skirts which carry ring-shaped sonic parts. These are made from abrasive particles, such as diamond dust, and a metal or metal alloy die of selected hardness. Such cutting blades produce cutting surfaces in hard material which are essentially free from damage. The cut material meets the requirement for which it is cut and the knife produces a sufficient number of slices to make the process economical.
W 71/1 -1-

009886/1298 6AD ORIGINAL

Another object of the invention is the formation of ring-shaped Cutting knives of the type described "in which the cutting width is kept to a minimum" around the thing to be cut to conserve costly material and eliminate the waste of material associated with subsequent grinding operations is.

Another object of the invention is to make it more annular Cutting knife of the type described, in which the volume ratio the abrasive particles to the metal die is increased significantly, thereby extending the normal life of the knives and to increase the cutting speed thereof, so that the production numbers of the cutting machine can be improved.

Yet another object of the invention is education annular cutting knives of the type described, which exhibit a considerably reduced deformation of the knife in use, to increase the effectiveness of the sons' oath and to produce cut hard material having cutting surfaces substantially free of damage.

Other features of the invention are in part understood and in part described below.

In the drawing shows:

Fig. 1 is a plan view of an annular cutting knife according to the invention,

Fig. 2 to a larger extent & from a cross-section along the line 2-2 of Fig. 1,

3 shows a cross section of another embodiment, Fig. 4 in plan a further embodiment and

5 on a larger scale from a cross section along the line 5-5 in FIG. 4.

W 71/1 -2-

009886/1298 bad ORIGINAL

In Fig. 1, 10 is an annular cutting knife according to the invention designated. The same consists of an annular disc 1 1 made of aluminum, steel, brass or the like. The disc may have a thickness of 0.025 to 0.10 mm or more.

The inner annular edge of the knife 10, generally indicated by, is provided with an annular cutting part 13, which can cut very hard materials. The cutting part 13 is made of abrasive particles such as diamond dust, Aluminum oxide or the like, which are distributed in a die made of metal or metal alloy.

While with the usual cutting knives the abrasive particles ^ are distributed in a die made of relatively hard metal or metal alloy, according to the invention, the die is relative soft. The die can therefore be made of nickel, BM-tin, tin-copper, bismuth-tin (with a diamond pyramid hardness of 75/100), made of soft copper (with a diamond pyramid hardness of 100/125) and other corresponding metals and metal alloys exist. However, the hardness of the selected metal or metal alloy should not exceed a diamond pyramid hardness of 275.

The cutting portion 13 can be made by electroplating the mixture of diamond particles and the selected metal or metal alloy in the manner described in the American | Canadian patent 3 356 599 is described in more detail. The volume ratio of the diamond particles to the metal matrix can be in the range of 40 to 5% , the precipitate having a radial thickness on the basis of 1 to 3 superimposed particles.

As Fig. 2 shows, the cutting part 13 consists of the edge parts 14, 15 and a connecting radial part 16. If the knife core has a thickness of 0.050 mm and the edge parts 14, 15 each have a thickness of 0.025 mm, the result is a cut edge with a thickness of 0.10 mm.

W 71/1 _ ₅ .

009886/1298 BAO ORIGINAL

. 1 Q β ο ο 7 ο

It has been found that when using the cutting blades according to the invention, the cutting surfaces of the cut hard materials essentially free from damage to the surface, pitting etc. are. The usual sole-grinding processes are therefore superfluous. This also causes a loss of material due to the grinding process eliminated and the hard material can be cut to a thickness equal to the required finished thickness is.

It has also been found that when using the knife according to the invention the deformation of the knife under load is significantly reduced and the actual cutting load decreases, so that the cutting speed of the knives is increased with a corresponding increase in production numbers.

As FIG. 3 shows, the invention can also be applied to knives 10A for thrusting or parting off. In this case, the metal core 11A of the knife only has one on its radial edge 17 Cutting part 1YES. This is similar to that shown in FIG Cutting part 13

Figures 4 and 5 show another embodiment of the invention, according to which the annular knife 20 has a metal core 21 which has a cutting part 22 on its outer edge 22 wearing.

The cutting portion 22 has an outer layer 24 composed of abrasive particles distributed in a metal die are, as well as an inner layer 25 of metal, which with the Layer 24 is firmly connected. The layer 24 is formed by a mixture of a relatively soft metal or a Metal alloy with a hardness equal to that of the diamond pyramid hardness of not exceeding 275, and of abrasive particles, such as diamond particles of selected size, electrodeposited on a mold is deposited, whereupon the electrodeposition of the metal forming the layer 25 takes place on the layer 24. The composite cutting portion 22 is then removed from the mold.

W 71/1 .4.

009 886/1298 8AD ORIGINAL

The metal of layer 25 is compared to the hardness of the metal die the layer 24 is quite hard and can be made of nickel, nickel-cobalt and the like exist. Such metals and alloys have a hardness that exceeds the diamond pyramid hardness of 500.

The preformed cutting part 22 rises on its inner periphery machined a precise diameter while the core 21 on its outer circumference is also machined to an exact diameter, which is slightly larger than the inner circumference of the Cutting part 22. The core 21 is then cooled to a low temperature so as to reduce its outer circumference, thus the same can be combined with the cutting part 22. When the room temperature is reached, the core 21 with the cutting " part 22 are in tight engagement. The core 21 and the cutting part 22 can, however, also by brazing, soft soldering or a adhesive made of epoxy resin.

It goes without saying that the size of the diamond particles or others becomes evident Abrasive particles selected according to the type of cutting, slotting or parting operation and the type of being cut material to be abutted or cut off.

True! The invention, in particular knife with a relatively thin metal core is applicable, the same can also be found on knife application with cores having relatively larger thicknesses i. The cutting parts, which consist of the abrasive particles and the soft metal matrix, can also have variable radial and edge dimensions, which are determined by the type of material to be cut, stabbed or stabbed, as well as the desired cutting width.

The diamond pyramid hardness is known in catfish with a micro hardness tester measured by TUKON.

Claims

W 7V1 -5-

009886/1298

Claims (9)

Dr. Ing. E. BERKENFELD ■ Dipl.-Ing. H. BERKENFELD, patent attorneys, Cologne 196387 Plant -, s ι ι AldanzMdiwi i8. December 1969 Sch //, w aw Shirley I. Weiss Claims 1J cutting knife for hard materials, marked by a ring-shaped metal core and ropes ring-shaped Cutting part on one of the annular edge parts of the core * wherein the cutting part consists of a metal die and in the Die distributed abrasive particles consists and wherein the metal die has a hardness that corresponds to the hardness of the diamond pyramid does not exceed 275. 2. Cutting knife according to claim 1, characterized in that that the cutting part is electrodeposited on the inner annular edge of the core. 3. Cutting knife according to claim 2, characterized in that that the die is selected from the group consisting of lead-tin, tin-copper, bismuth-tin, soft copper, Nickel, copper, iron and mixtures thereof. 4. Cutting knife according to claim 2, characterized in that the abrasive particles 40 to 85 volume ^ des Make out the cutting part. 5. Cutting knife according to claim 1, characterized in that that the cutting part is arranged on the outer annular edge of the core, that the son's part is made of a backing layer made of metal, which is firmly connected to a metal matrix, in which abrasives are distributed and that the metal base layer has a hardness of * which is greater than the hardness of the metal of the metal die. W 71/1 -6- 009886/1298 SAD original 6. Cutting knife according to claim 5> characterized in that that the cutting part and the core are attached to one another by shrink fitting. 7. Cutting knife according to claim 1, characterized in that the cutting part on the radial edge of the core and on the to the radial edge adjoining edge parts adheres. 8. Cutting knife according to claim 1, characterized in that the cutting part is relative to the radial edge of the core in extends radial direction. 9. Cutting knife according to claim 1, characterized in that that the metal die has a hardness which is a diamond pyramid hardness corresponds to from 75 to 275. W 71/1 -7- 009886/1298 _fiW > o «Q« * At. Blank page