Cutting insert

Details Cutting insert Cutting insert

1998-06-01

1999-08-10

Pitts, Andrea L.

Cutters, for shaping

Including tool having plural alternatively usable cutting edges

With integral chip breaker, guide or deflector

407115, 407116, B23B 2722

Patent

active

059348445

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The present invention relates to cutting inserts of the type that are referred to as disposable cutting inserts or indexable cutting inserts and which are adapted to be detachably mounted on a tool holder for mounting in a machine tool for cutting operations, primarily turning operations. More particularly still, the present invention is concerned with the formation of the cutting edge land area and the chip controlling groove in a circular cutting insert. Such cutting inserts are usually made of coated or uncoated cemented carbide but different ceramic hard materials are also feasible.
A round cutting insert can often cope with a large variety of profiling operations ranging from finishing to roughing. Their round relief surface is usually of a frustoconical shape in order to allow for sufficient clearance. Because of this clearance, they are normally single-sided. They have a wide capability in chip control and are allrounders that generate a good surface texture even at high feed rates. However, they also entail some drawbacks, such as the fact that it is not possible to choose a particular entering angle at a particular cutting depth. Furthermore, it is not possible to select an appropriate entering angle as a function of the feed. This of course is due to the fact that round inserts have a basically uniform cutting geometry around the whole circular cutting edge. As examples of such cutting inserts, reference is made to U.S. Pat. No. 4,606,678.
In U.S. Pat. No. 3,383,748 a round cutting insert is disclosed with a circumferential chip-breaking groove along the circular cutting edge. This groove may have a varying width and depth and is stated to produce chip control at light chip loads as well as at heavy chip loads by orienting the groove in the appropriate position with respect to the active portion of the cutting edge. However, this cutting insert causes swarfing problems in general and does not work satisfactorily, particularly at small cutting depths, because the chips are not broken properly.
Further, DD-C-264 391 discloses a round cutting insert which comprises six planar chip surfaces around the circular cutting edge. However, in practice, this cutting insert does not work properly because the planar chip surfaces do not manage to break the chips, which rather pass over the step-like shoulder unbroken. Further, the center island extends at six points practically to the very cutting edge, which is impractical because these extending portions become fragile and easily broken.


SUMMARY

Thus, it is a primary object of the present invention to provide a round cutting insert which achieves a good chip control at low as well as high feeds.
It is a further object of the present invention to provide a round cutting insert which achieves a good chip control at small as well as large cutting depths.
Still another object of the present invention is to provide a round cutting insert which can be indexed according to different cutting depths and feeds.
These and further objects have been achieved by shaping the cutting insert according to the features as defined in claim 1. Preferred embodiments of the cutting insert are defined in the dependent claims.
A preferred embodiment of the invention will now be described with reference to the appended drawings. A brief description of the drawings follows below.


BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a cutting insert according to the invention, obliquely from above.
FIG. 2 shows a top view of the cutting insert according to FIG. 1.
FIG. 3 shows a perspective view of the cutting insert sectioned at III--III in FIG. 2, obliquely from above.


DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The illustrated cutting insert according to the present invention is generally designated by reference numeral 1. It comprises a top surface, a round clearance surface 2 and a planar bottom surface 3. The clearance surface 2 may be substantially perpendicular to the top surface and the bottom surface 3, thus with an i

REFERENCES:
patent: 3187406 (1965-06-01), Franko
patent: 3786541 (1974-01-01), Lundgren
patent: 3968550 (1976-07-01), Gehri
patent: 4247232 (1981-01-01), McCreery
patent: 4606678 (1986-08-01), Zweekly
patent: 4626140 (1986-12-01), Zweekly
patent: 5116167 (1992-05-01), Niebauer
patent: 5203649 (1993-04-01), Katbi et al.

Affiliated with

Also associated with

Rating

Cutting insert does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Cutting insert, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cutting insert will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1113114