MXPA96004095A - Positive cutting insert with compound clearance faces - Google Patents

Abstract

The present invention relates to a cutting inset with compound clearance faces for use in milling operations. The first clearance face proximal to the cutting edge is radiuses and the second clearance face is planar.

Description

CUTTING POSITIVE INSERTION PIECE WITH COMPOSITE SEPARATION FACES Field of the invention.

The present invention relates to a cutting insert with composite separating faces, for use in milling or grinding operations. The first separation face close to the edge or cutting edge is rounded and the second separation face is flat. The present invention is further related to cutting inserts (or inserts) which are pressed to the final shape. The present invention also relates to a cutting insert which obtains geometries of the cutting face and of the separation faces which were previously available only with the cutting tools of the rectification type. The present invention is further related to a metal cutting insert having improved cutting edge strength.

Description of the related art U.S. Patent No. 5,071,291 issued to Kaminski discloses a cutting or milling cutting blade with an improved cutting insert. The cutting insert has a general wedge shape with REF: 23036 an upper surface which is ground (or ground) or otherwise formed to be concave whereby a pair of coplanar cutting edges running back symmetrically from a corner or more forward cutting point. In particular, the top surface of the insert consists of a pair of flat triangular top faces sloping downwardly at a negligible angle to the center of the insert. The pair of cutting edges formed by this manner are generally V-shaped and coplanar. There is no presence of the separation faces present in this application. Therefore the present application differs from the '291 patent of Kaminski. U.S. Patent No. 5,078,550, issued to Satran et al., Discloses a cutting insert for use in rotating milling or grinding cutting elements. The insert has a lateral relief flank and a lateral base edge defined between the lateral relief flank and a base surface. The lateral relief flange comprises a first and a second side relief flank surface which are in an intersection line. The first lateral relief flank of the component extends along the lateral relief flank from a first portion adjacent a leading end of the insert and located at an intermediate position thereof to a second position intersecting the cutting edge and adjacent to a rear end of the insert.

The component flank surfaces are substantially planar and angularly disposed relative to each other, such that a lateral relief angle of the insert, defined with respect to the cylindrical carrier in the region of the leading end substantially equals a lateral relief angle. of the insert in the region of the rear end. Satran's '550 patent differs from the present application because the relief flank surfaces components of the Satran' 550 patent are flat, while the flank relief surfaces components of the present invention consist of a first surface of relief flank curves convexly, as seen in a side sectional view and a flat secondary relief flank surface. It has been determined that a first rounded spacing adjacent the cutting edge imparts improved strength to the cutting edge. Therefore, the present invention differs from the '550 Satran patent.

BRIEF DESCRIPTION OF THE INVENTION The present invention consists of a cutting insert having composite separation faces and which can be formed without the need for face grinding or grinding operations. The insert is a polygonal adjustable cutting insert having improved edge strength. The insert consists of a top surface, a flat bottom surface which is smaller than the top surface and a side wall that extends outwardly at an obtuse angle from the bottom surface and intersects the top surface to define the body of the insert. The intersection of the side wall and the top surface defines a cutting edge. The side wall consists of sidewall portions which are defined as that portion of the side wall which extends from one corner of the insert to the adjacent corner of the insert. Each lateral flank comprises a primary separation surface and a secondary separation surface. The primary separation surface is convexly rounded, as seen in the side sectional view and extends from the cutting edge at a distance on the intermediate flank to the upper and lower surface. The secondary separation surface is flat and extends along the flank from the lower surface to intersect the primary separation surface at the distance previously described, intermediate the upper and lower surfaces. The insertion of the secondary separation surface and the lower surface form the separation edge of the insert. The top surface of the insert may be flat or have a curved spacing face, or may be provided with a variety of different top shapes, which include different geometries and chip breakers as they are within the reach of those of ordinary experience in the technique.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a top perspective view of the polygonal insert. Figure 2 is a top plan view of the polygonal insert. Figure 3 is a plan view of the end of the insert showing the composite separation surfaces. Figure 4 is a detailed view of the insert in a tool holder.

Detailed description of the preferred modality Turning now to the drawings in which like reference numerals show similar structures, the insert 10 consists of an upper surface 12, a flat lower surface 14, which is smaller than the upper surface and a side wall 16 which is extends outward from the lower one at an obtuse angle and intersects with the upper surface to define a body 18 of the insert. The orientation of the side wall to the upper and lower surfaces provides the insert with a positive separation orientation.

The intersection of the side wall with the upper surface defines the cutting edge 20 which, as can be seen in figure 2, is straight. The intersection with the lower surface defines the separation edge 22 which, as can be seen in the drawings, is also straight line. The side wall comprises the sidewall portions 24. Each sidewall portion is composed of a primary separation surface 26, which is adjacent to the cutting edge and a secondary separation surface 28, which is adjacent to the separation edge. The primary separation surface, as seen in a side sectional view, is convexly curved. The curved primary separation surface imparts improved strength to the cutting edge and also provides extra clearance along the flank of the insert. The secondary separation surface is flat and intersects with the primary separation surface at some distance d, along a junction line 30, which is intermediate to the upper and lower surface. The top surface can be provided with a variety of top shapes and chipbreakers depending on the material to be cut and the use to which the insert will be placed. For example, the insert could be equipped with a convexly curved upper surface 32 or any other upper shape desired by the designer.

The insert is designed for use in a peripheral milling cutter or rotary cutting element having replaceable inserts. Those skilled in the art will recognize that many variations are possible without departing from the scope and spirit of the invention.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention is the conventional one for the manufacture of the objects referred to therein.

Having described the invention as above, the content of the following is claimed as property

Claims (3)

Claims

1. A polygonal adjustable cutting insert for peripheral rotating or rotating cutting elements, characterized in that it comprises: an upper surface, a flat lower surface smaller than the upper surface and a side wall that intersects the lower surface to define a separation edge and that extends outward from the lower surface at an obtuse angle and intersects the upper surface to define a body; the intersection of the side wall and the top surface define a cutting edge; the side wall comprises sidewall portions which extend from one corner of the insert to the adjacent corner of the insert; each sidewall portion comprises a primary separation surface and a secondary separation surface; the primary separation surface is convexly curved and extends from the cutting edge to a joining line at some distance along the intermediate flank to the upper and lower surface; the secondary separation surface is flat and extends along the flank from the separation edge to the joint line.

2. The insert according to claim 1, characterized in that the upper surface has a convexly curved separating face.

3. The insert according to claim 1, characterized in that The upper surface includes a superior shape design.