Cutters – for shaping – Including holder having seat for inserted tool – With separate means to fasten tool to holder
Reexamination Certificate
1999-08-31
2001-06-12
Tsai, Henry (Department: 3722)
Cutters, for shaping
Including holder having seat for inserted tool
With separate means to fasten tool to holder
C407S110000, C407S114000, C407S116000
Reexamination Certificate
active
06244789
ABSTRACT:
This application is based on an application No. 10-245675 filed in Japan, the content of which is incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an indexable insert for cutting processing and a cutting tool having the indexable insert. More specifically, it relates to an indexable insert and a cutting tool having the indexable insert suitable for inner diameter processing of a small hole or a very small hole in a small-sized component such as a component for OA equipment, an electronic component, or a small diameter bearing.
2. Description of the Proir Art
Conventionally used as an inner diameter processing tool have been a throwaway type in which a chip
22
is fastened to a front end of a holder
21
so as to be attachable or detachable as shown in
FIG. 6 and a
brazing type in which a chip
32
is fastened by brazing to a front end of a holder
31
as shown in FIG.
7
.
The brazing type requires a lot of time to replace the chip
32
when the chip's edge is damaged, which is not economical. Accordingly, the throwaway type is currently used in most cases.
The throwaway type is generally used for processing a large-diameter hole in a large-sized component such as an automobile component, however, this type is not used for processing a very small-diameter hole in a small-sized component such as a component for OA equipment or an electronic component. A solid cutting tool as shown in
FIG. 8
is generally used for processing the very small-diameter hole.
Referring to
FIG. 8
, the integral cutting tool is constituted by a chip
45
and a sleeve
46
for supporting the chip
45
by fastening. The chip
45
is generally formed by cutting a cylindrical member, so that a cutting edge
44
and a holder
43
are integrally composed of the same material.
The chip
45
of such a solid type has a structure in which the holder
43
is inserted into the sleeve
46
, and is fixed to the sleeve
46
by tightening a set bolt (not shown) from the outside of the sleeve
46
.
In such a structure, a force for the sleeve
46
to clamp the indexable insert
45
is weak, so that chatter vibration is liable to be generated in the chip
45
. The repetition accuracy of the cutting edge
44
is low. Further, the diameter at a front end of the sleeve
46
is larger than that of the cutting edge
44
of the chip
45
, so that a front end surface of the sleeve
46
expands in a collar shape toward the chip
45
. Therefore, the front end surface of the sleeve
46
is positioned so as to close a hole of a work piece at the time of inner diameter cutting processing, resulting in poor cutting chip discharge properties. Further, when the sleeve
46
is used, undercut processing cannot be performed.
SUMMARY OF THE INVENTION
The present invention has been made in order to solve the above-mentioned problems of the prior art.
A primary object of the present invention is to provide an indexable insert having good clamping properties. Another object of the present invention is to provide a cutting tool for reliably clamping the indexable insert not to generate chatter vibration. Still another object of the present invention is to provide a cutting tool with high index accuracy at the position of a cutting edge. A further object of the present invention is to provide a high-performance indexable insert being superior in cutting chip discharge properties and capable of performing undercut processing and an inner diameter cutting processing.
The above-mentioned objects of the present invention are achieved by an indexable insert as set forth in claim
1
and a cutting tool as set forth in claim
5
.
As described in claim
1
, an indexable insert according to the present invention has a base and a stick-shaped portion which are integrally formed. The base comprises a bottom surface placed on a seating surface of a holder and a first side surface and a second side surface. The indexable insert is attachable to the holder such that backlash is prevented by clamping the first side surface and the second side surface.
A cutting edge and a rake face are provided at a front end of the stick-shaped portion. Moreover, one side surface of the stick-shaped portion is a side relief face, and connects with the base with no step. Accordingly, cutting chips are satisfactorily removed.
The indexable insert is formed of the same material. Accordingly, it is preferable that the diameter of the stick-shaped portion and the thickness of the base are the same, as described in claim
2
.
As described in claim
3
, when a side curved surface and a recessed notch connecting with the side relief face are formed on the rake face, cutting chips are smoothly guided to the side relief face.
When the cutting edge has brought into a concavely curved shape, as described in claim
4
, cutting chips are curled, so that the cutting chips are easily removed.
A cutting tool according to the present invention constrains the indexable insert by a first clamp surface and a second clamp surface, as described in claim
5
. More specifically, a side surface of the base of the indexable insert is clamped at four points by a projection at a front end of the first clamp surface, two projections at a front end and a rear end of the second clamp surface, and a set bolt at a rear end of the first clamp surface. Accordingly, neither backlash nor chatter vibration is produced in the indexable insert attached to the holder during cutting.
The base of the indexable insert fitted in an insert pocket of the holder is not concealed as in a case where a sleeve is used but is exposed from the holder. That is, a top surface of the indexable insert fixed to the holder is exposed from the holder. Therefore, the indexable insert is easily attached to the holder. Moreover, the indexable insert can be firmly fixed to the holder using a bolt, a clamp, or the like. Accordingly, it is possible to prevent chatter vibration from being generated in the indexable insert.
The side relief face of the indexable insert connects with one side surface of the holder so as to be flush therewith, so that the holder does not prevent the cutting chips from being removed.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 3758927 (1973-09-01), Stein
patent: 4396315 (1983-08-01), Middleton
patent: 4607988 (1986-08-01), Salm et al.
patent: 5362183 (1994-11-01), Alario et al.
Hogan & Hartson LLP
Kyocera Corporation
Tsai Henry
LandOfFree
Indexable insert and cutting tool having indexable 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 Indexable insert and cutting tool having indexable insert, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Indexable insert and cutting tool having indexable insert will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2539177