WO1988003457A1

WO1988003457A1 - Process for the manufacture of milling cutters incorporating macrograins of abrasive material, such as silicon carbide

Info

Publication number: WO1988003457A1
Application number: PCT/DE1986/000384
Authority: WO
Inventors: Werner Foppe
Original assignee: Werner Foppe
Priority date: 1986-11-05
Filing date: 1986-11-05
Publication date: 1988-05-19

Abstract

In the process described, milling cutters incorporating macrograins of hard, sharp-edged, abrasive material exploit the abrasive quality of the grains, during rotation of the milling cutter at high speed and render the usual cutting blades unnecessary. Hand-held milling equipment fitted with blades is difficult to use and inaccurate for woodworking; it may prove highly dangerous, the device tending to break away with a change of grain direction. In contrast, milling cutters incorporating coarse, sharp-edged grains can be manufactured in many different shapes, thereby making work clean and safe and increasing the service life in wood containing sand or metal inclusions. Milling cutters incorporating macrograins are therefore ideally suited for use in tree surgery.

Description

'Process for the production of milling bodies by macro-grain loading from abrasive materials, such as silicon carbide'

The invention relates to a method for producing high-speed milling bodies, in the surface of which an abrasive macro-grain layer is firmly anchored, which can be used for milling wood or similar materials. These milling bodies according to the invention are particularly suitable for non-stationary high-speed milling devices.

Such milling devices are urgently needed, for example, in tree surgery and preferably have a working surface diameter of 25 mm to 125 mm.

So far, milling cutters with cutting tools made of metal have been used for this work area, which pose a high risk of accidents to the user and are to be managed imprecisely, since the devices break out easily in the case of fiber changes in the wood and are limited in use due to the design of the necessary protective devices. In addition, there are high acquisition costs and wear increases rapidly if sand or stone inclusions and ingrown iron parts in the trunk area are used in the base area of the trunk.

By the invention. The use of macro-grain made of silicon carbide or similar hard, sharp-edged materials on a form-fitting and burst-free carrier material hard, sharp-edged material due to the high rotational speed and the movement of the manipulator used as a cutting edge, which enables a comparable or higher work progress than is the case with metal milling cutters, while eliminating their disadvantages.

At high circulation speeds, • which are generated primarily with compressed air-operated devices, the cutting forces on the macro grain decrease and the power factor as well as the specific chip performance and the edge and profile retention increase disproportionately. With increasing speed of rotation, the risk of breakage or breakout of the cutting grain also decreases as long as the centrifugal forces that arise do not exceed the adhesive forces of the tool. This ensures that the device is guided smoothly as the work progresses and that the shape is worked out precisely.

The metal-cast milling bodies according to the invention as claimed in claim 1 a are to be etched again after wear and thus to be used repeatedly, the working surface, however, becoming smaller after each etching pass.

Milling bodies made of synthetic resin as a carrier substance according to claim 1 b are only to be renewed after surface treatment of the macro grain by surface coating, as described in claim 3 according to the invention.

These milling bodies and milling disks according to the invention can be used not only in the mentioned area of tree care but also in the area of the timber construction industry and in the home improvement area.

Claims

Patent claims

1. Process for the production of milling bodies with macro grain (grain size between 1 and 10, according to US standard test sieve) from silicon carbide, high-grade aluminum oxide and similar hard, sharp-edged, abrasive materials, by casting with metal or synthetic resin into a mold in which a) the macro grain poured into the metal is exposed to work after hardening by etching or b) the macro grain to be bound in synthetic resin is absorbed up to two thirds in an adhesive layer on the inside of the mold before casting and after hardening of the synthetic resin body carrying the grain of high tensile and shear strength of 40 N / mm ^2, the adhesive layer is removed, whereby the milling grain intended for work is released.

2. Process for the production of milling disks by casting a 1-3 mm thick metal disk, in the melt surface of which macro grain with a grain size of 1-10, according to the US standard test sieve, is sprinkled.

3. Process for the production of milling heads and milling disks by coating prefabricated metal blanks with synthetic resin and subsequent sprinkling of macro-grain in the grain size 1-10, in accordance with the US standard test sieve, and subsequent thermal curing of the load-bearing synthetic resin layer to high tensile and shear strength.

4. Process for the production of milling heads from technical ceramic materials by filling with macro grain in the grain size 1-10, according to the US standard test sieve.

5..Verfahren according to claim 1, characterized in that the shape of the milling part of the tool to be created with macro grain of silicon carbide, high-grade corundum and similar materials in the grain size 1-10, according to US standard test sieve, filled and poured with aluminum becomes.

6. The method according to claim 1, characterized in that the synthetic resin forming the milling body is mixed with carbon fibers before casting for reinforcement.