Cutters – for shaping – Including tool having plural alternatively usable cutting edges
Patent
1997-09-08
1999-10-12
Pitts, Andrea L.
Cutters, for shaping
Including tool having plural alternatively usable cutting edges
407114, B23B 2716
Patent
active
059645520
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to a method and a cutting insert for threading. The method aims to produce a thread in a rotary work piece, wherein a threading insert, including at least one cutting tip, creates the shape of the thread through a number of passes along the work piece. The threading insert aims to create threads including two thread flanks in a work piece, by flank infeed and comprises at least one cutting tip provided with cutting edges.
PRIOR ART
In known indexable threading inserts the cutting tip is in top view identical with the profile of the finished the thread, which means that at flank infeed, wear develops on the passive flank of the cutting tip due to abrasion from the work piece. Thereby these cutting inserts can not attain optimal tool life or reduce the time for processing at threading. At flank infeed a chip is obtained with rectangular cross section, which is easy to shape and handle in comparison with a chip from radial infeed, when the chip assumes a rigid V-shaped cross section. This fact together with a more efficient heat deduction from the cutting tip makes it possible to work with bigger chip thickness and to complete the thread with the same number of passes as by radial infeed. When conventional threading inserts are fed inwardly, parallel with one flank of the thread, the cutting edge facing said flank will not perform any cutting work but will only drag along said flank; something which can have an abrasive effect on the cutting edge and which can give bad surface finish on the thread flank. One has tried to feed the cutting tip at an angle which is smaller than the flank angle to avoid these negative effects, but then chips obtained from the side of the minor cutting edge have been thin and entangled, which has influenced tool life and surface finish.
OBJECTS OF THE INVENTION
One object of the present invention is to provide a cutting insert for flank infeed, which has good tool life.
Another object of the present invention is to provide a cutting insert for flank infeed, which reduces the time for processing at threading.
Another object of the present invention is to provide a cutting insert for flank infeed, which requires less energy to cut.
Still another object of the present invention is to provide a method for flank infeed, which gives good production economy.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a threading insert according to the present invention in a top view.
FIG. 2 shows the threading insert, in a side view.
FIG. 3 shows the tip of the threading insert in engagement with a dashed work piece. FIG. 3 is similar to FIG. 3 but references additional characteristics of the insert tip.
FIG. 4 shows a threading period of five passes with the tip of the threading insert.
FIG. 5 shows the tip of the threading insert in engagement with a work piece.
FIGS. 6 and 7 show alternative embodiments of cutting corners on threading inserts according to the present invention.
FIGS. 8 and 9 show alternative embodiments of threading inserts for trapezoidal threads, according to the present invention.
FIGS. 10 and 11 show cross sections of the cutting inserts in FIGS. 8 and 9, respectively.
FIG. 12 shows the tip of the threading insert according to FIG. 9.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
With reference to FIGS. 1 and 2 a cutting insert according to the present invention is designated by 10. The cutting insert preferably is made by coated cemented carbide. The cutting insert has a substantially triangular basic shape and comprises an upper and a lower side 11 and 12 respectively. The basic shape can also be square for example, such as is shown in FIG. 9. The sides 11 and 12 connect substantially perpendicularly to side surfaces 13, 14 and 15. The side surfaces form an acute angle of about 60.degree. with each other. The cutting insert has a central hole 16 for receiving a fastening device for clamping of the cutting insert against a cutting insert pocket of a holder, not shown. The cutting insert is prov
REFERENCES:
patent: 3813746 (1974-06-01), Price
patent: 4278370 (1981-07-01), Spear
patent: 4281430 (1981-08-01), Hellnick
patent: 4505626 (1985-03-01), Benhase
patent: 4575888 (1986-03-01), Muren
patent: 4674924 (1987-06-01), Carlsson et al.
Pitts Andrea L.
Seco Tools AB
Williams Mark
LandOfFree
Method and cutting insert for cutting screw threads in metal wor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and cutting insert for cutting screw threads in metal wor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and cutting insert for cutting screw threads in metal wor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-646389