Abrading – Machine – Rotary tool
Patent
1997-10-20
2000-05-02
Eley, Timothy V.
Abrading
Machine
Rotary tool
451548, 451559, 451450, B24B 2700
Patent
active
060566280
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a grinding cup for grinding of cutting inserts of a rock drill bit, said grinding cup comprising a shank rotatably mounted in a grinding machine and a wear part being provided with a recess effectuating the grinding of the cutting inserts. The invention also relates to a wear part for the grinding cup.
PRIOR ART
During grinding of cemented carbide cutting inserts of a drill bit, a grinding cup of the above-captioned type is often used. The wear part of such a grinding cup usually has an abrasive grinding surface which often comprises diamond particles. A grinding cup for a handheld insert grinding machine is known through SE-B-469 970. The grinding cup is provided with a specially designed rubber bushing, which has been mounted to the shank of the grinding cup. The function of the bushing is to decrease the transfer of vibrations from the grinding cup to the handheld holder body of the grinding cup. The bushing is however, mechanically unprotected, such that the bushing may be subjected to mechanical and abrasive loads.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a grinding cup that reduces transfer of vibrations from the grinding cup to the grinding spindle in connection with grinding of drill bit cutting inserts by avoiding entrance of abrasive material to the active contact surfaces. Other objects of the present invention is to provide a grinding cup that has a good stability and a good length of life. The above-mentioned objects have been achieved by providing a grinding cup that is characterized by the features of the appended claims.
DESCRIPTION OF THE FIGURES
Below embodiments of a grinding cup according to the present invention will be described with reference to the appended drawings, wherein:
FIG. 1 shows a side view of a grinding cup according to the present invention;
FIG. 2 shows a side view of an alternative embodiment of a grinding cup according to the present invention;
FIG. 3 shows a side view of still another alternative embodiment of a grinding cup according to the present invention;
FIG. 4 shows still another alternative embodiment of a grinding cup according to the present invention, in a partly sectioned side view; and
FIG. 5 shows a cross-section of an exchangeable wear part according to the present invention, according to the line V--V in FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
The grinding cup 10 according to FIG. 1 comprises a shank 11, a wear part 12 and an intermediate portion 13 connecting the shank 11 with the wear part 12. Preferably the shank 11 and the intermediate portion 13 are made in one piece. The intermediate portion consists of a number of connected components, see below. The grinding cup 10 is rotationally symmetric relative to its longitudinal center axis 14.
The free end of the wear part 12 has a recess 15 in the shape of a spherical segment, when the cutting inserts 16 to be ground have semi-spherical free ends. The cutting insert is preferably made of cemented carbide. If the cutting insert however, has ballistic, conical or other shape on its free end, the recess will of course have a corresponding shape. The recess 15 is adapted to be in engagement and cooperate with the free end of a cutting insert to be ground. The wear part is made of sintered powder and at least the recess is being provided with an abrasive material, preferably diamond. The other parts of the grinding cup is preferably made from steel.
The intermediate portion 13 of the grinding cups 10 can be provided with a key grip at its upper portion provided to cooperate with a driving means of the grinding machine to rotate the grinding cup 10. A central flush channel 18 extending axially, extends between the free end of the shank 11 and a central and/or eccentric orifice in the recess 15. The shank 11 and the intermediate portion 13 may alternately be provided with other conventional geometries, suited for different kinds of grinding machines available on the market.
The radially outermost border line
REFERENCES:
patent: 2542154 (1951-02-01), Mesirow
patent: 2666307 (1954-01-01), Higert
Bergqvist Arne
Nava Peter
Eley Timothy V.
Sandvik AB
LandOfFree
Grinding cup and wear part with vibration dampening means does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Grinding cup and wear part with vibration dampening means, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Grinding cup and wear part with vibration dampening means will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1590135