Note: Descriptions are shown in the official language in which they were submitted.
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_AC~GROUND ~F TIIE INVENTION
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The present 1nvention broadly relates to tools for
machine tools and pertains, more specifically, to a new and
improved tool for machining workpieces, particularly a cutter
for the cutter head of a gear-cutting machine.
~i~ Generally ;speaking, the tool for machining
workpieces of the present development is of the type
comprising a cutter shank, a cutting tip or plate located in
a recess or cutout of~the cutter shank, screw-type means for
disp1ac1ng the~cutt1ng~tip w1thin the;recess or cutout of the
cu~ter shank, and means for fastenlng the cutting tip to the
cutter ahank.
In a known tool of the aforemel1ticned t~pe as
discLosed, for example~, in German Patent No. 3 r 211~ 727 ~
pub1ished ~ugust 11~, 1983, there is provided a s11ank, one end
of which is constructed in the for1n of a cutting-tip holder
with two tip seats. ~razed into each o the two tip seats is
a cutting tip. Each cutting tip comprises a support or base
of a thickness of ~hout ~ mm to 6 mm and a layer or coating
having a ~hickness of about 0.8 mm to 1.0 ~im and applied to
the suppGrt OL base by sinter1ng The support or base
con2ists of hard metal such as tungsten csrbide, while the
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la~-er appl~ied~:b~s~intèriny~to ~the sùppor~t or:~ase consists of :; ~ ,
cubic~:~orcn~nl~r~lde~ a~l:so~nown as CBN~
hen thê~ t ng~ i s~aFe~brazed;or welded to the
respectivé~t`ip~-s~ ts of:~the~cut~ting- ip~:holder, there is a
el~ b~ 1 e- ~r coat~Dg ~ ~,
In~: t~ ~ oL~j.o~~thls~t;yp~known~to~the~art and
d,~f ~ ~ ~ in~Pre h atent~No~ 1,254,498,
ar~1, ~ is used à~cuttlng tip~m e~
¢a ~ de r ~ b ~ àL~ hi;àh-spéè-d:~or~rapid machining
t ~ `:e~ f~ a~cutt r~ shank~or:~or~
~r ~ uL, in
o~t~ ~ pla~e~ . tt~ing edge~
of~-thq cut~1n~tip;~s a ~anged:~p~ara~1~1el to the~:bottom or ??ase
~'`~?~'~è~ceS9~t ~ the~- ~9
or~ a~tion::of~the~cutti
shiank ~` : o ~: ol ~s~ s;up ose ;~to:;p bvent~ S
ct lD~O~ ~ t ~ 'th2 :evàn:t~ u
ots~o~ cutting pr ss;or;~ln~ e
~ `Qr.:~abrupt~:~stop~o:f~t ~machl~ne~ at~ Jh1ch the:workp1ece 15
?'`~ moun;te~d.~
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~U~ARY OF TEIE INVENTION
herefore, wlth the foregoing in mind, it is a :.
primar~y object of the present invention to provide a new and
improved construction of a tool for machining t~orkpieces -.
~hich is not afflicted with the aforementioned drawbacks and
shortcomlngs of the prior art constructions.
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Another~and :more specific object of the present - :
:invention aims at providing a new and improved tool for
; : ~ machining workpieces by means of which tool, on the one hand,
the: cutting tip ls~moun~ea at the cutter shank to be
e:;chanaeable or replaceable as~readily as possible and, on ~ .
he other hand,~a~most rigid :possible mounting of the cutting
tip at the cu~ler:shank~is ensured.
ow }n order to implement ~hese and s~ill further
:ob~ects OL- the presen~ inventicn which ~ill become more
readily apparent as the description proceeds, the tool for
: :: :machlning workpieces ana: constructed according to the
inventlon is manlfestedr among other things, by the features . .
that the recess~or cu~out or the cutter shank lS structured
as a slot or groove Cormed oy two iateral surfaces or faces
and by a base or bottom, that ~ cutting edg2 of the cutting
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p is arranged approximately parallel to both the lateral
surfaces or faces cf the slot or groove, and that the cutting
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tip is clamped bett~leen both the lateral surfaces or faces of
the slot or groove by the aforenoted fastening means --
constltuting fastening screws, in that the two lateral
surfaces or faces are elastically or resiliently pressed
against the cutting tip.
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The advantage of this manner of mounting the
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cutting tip at the cutter shank is seen essentially in the
fact that rigid mounting of the cutting tip is ensured
notwithstandlng~easy or ~effortless exchangeability of the
cutting tip, and that regrinding of the cutting tip is
substantially facilitated. ;~
; In addltion to the~ cutting tip or plate, there is
advantageously clamped a~stop or butt plate in the slot or
groove of the cutter shank. The aforenoted screw-type means
constitute a screw or threaded bolt located in the stop or
butt plate and serving to positionally shift or adjust the ~ ;-
cutting tip. ;
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The cutter shank advantageously comprises at the
ronl end,thereof three surfaces which form two inbersection
lines, the slot being;arranged substalntially paralled to one
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-~ : RIEF DESCRIPTION OF TllE DRAWINGS .
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; The lnventlon will be better understood and objects
other than those set for~h above will become apparent when
cons~ideration is given to the following detailed description
thereof. Such description makes ref~rence to the annexed
: :drawlngs wherein throughout the Various figures of the
drawlngs, :there~have~been ge~nerally;used the same reference
characters~to~:denot~e~the~same or analogous components and
wher~ein~
:Figure~l:shows:a perspect~ive view of a cutter shank
os a~exemplary~embodlment of~ the lnventive tool for
~F ~ machining workpiece~s;~
Figure~2~shows;~a~perspectlve view of a cutting tip
and;or a siop~or~butt~:plate provided for the cutter shank
c-plcte~d~ in F-gure~
Flgure~3 shows ~a front view of the exemplary
: embodiment of the lnventive tool~for machining workpieces; :~ :
Figure 4 shows~ a~sicle~ view of the exemplary
embodiment of the:~inventive tool for machine workpieces;
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Flgure 5~shows ~ top plan view of the cutter shank
depicted in Figure l;
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Figure 6 shows, on an enlarged scale, a perspective
view of one of the two sides of the cutting tip depicted in ~-
Figure 2;
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Figure 7 shows, on an enlargjed scale, a view of the ; ;
rear end face of the cutting tip depicted in Figure 2; ~
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~ Figure 8 shows a pLan~view of the cutting tip ~
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depicted in Figure 2;; and ~ ~
Figure 9 shows, on an enlarged scale, a perspective
vlew of the other~ one~of the two sides of the cutting tip
depicted in Figure 2.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, it is to be understood
tha~ to simplify the showlng thereof, only enough of the
construction of the tool for machining workpieces has been
llustrated therein~as is needed to enable one skilled in the
art to readily understand the underlying principles and
concepts of this invention.
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~ Turning attention~now specifically to Figures 1 and
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2 of the drawings~, sn e.Yemplary embodiment of the inventive
tool for machining workpieces, e.g. a cutter for a cutter
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head of a gear-cuttlng machine, particularly a bevel gear
cutting machine, will be seen to comprise a cutter shank 10
also known as a cutting-tip holder, and a cutting tip or
plate 11 which can be inserted in a slot or groove 14 of the
cutter shank 10.
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This cutting tip 11 comprises the following
; components: (i) a base plate;28; (ii) a hard-metal support 12
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Figure 4) brazed~on~to bhe base plate 28 of the cutting tip
11; and (iii) a layer or coating 13 of cubic boron nitride --
applied to the hard-metal support 12 by means of sintering.
The hard-metal support 12 wi~h the sintered-on
layer or coating 13~ is a ~readlly~available and marketable ~ ;
commercial product which is particularly suitable for cutting -~:
hardened gear wheels.
The cutting~tip 11 inserted ln the slot or groove
14 of the cu~ter shank 10 is appropriately clamped or
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~ positionally rixed by suitable screws or threaded bolts 15 or
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~ the like. According to Figure 5, the cutter shank 10
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comprises at its front or top end three surfaces 16, 17 and
18 whereby, on the Gne hand, the~ surfaces 16 and 18 can be
considered to form an edge 31 and, on the other hand, the
surfaces 17 and 13 form an edye 31'.
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According to FLgure 1, the aforenoted slot or
groove 14 for accommodating the cutting tip 11 is located
between the surfaces 16 and 1~. This slot or groove 14
extends along the entire length of the cutter shank 10. In a .
lower part or portion 14a of this slot or groove 14 there is
1ocated a stop or butt plate 19 whlch, in~like manner as the ~- -
cutting tip 11, is clamped in the slot or groove 14 by means
of a further screw or threaded bolt 15 or the like. In this
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stop or butt plate 19 there is provided a screw or threaded
bolt 20 or equivalent structure, of which only the rear or
bottom end and the front or :top end are visible in Figure 1,
whereby the cutting tip 11 bears upon the front or top end of
the screw or threaded bolt 20. This screw or threaded bolt
; 20 located in the stop or butt~plate 19 serves to shift or
displace the cutting tip~11 within the slot or groove 14 in
the longitudinal direction of the cutter shank 10.
: According to Figures 2, 7 and 9, the cutting tip 11 ~-
: : comprlses a flank 21 and a true rake or chip surface 26 as
well as a head top face or clearance surface 27. A cutting ~ :
j edge 22 is formed by the true rake 26 and the flank 21.
~: The cutting tip lI comprises only this one cutting .
edge 22. The tool or cutter comprising the cutter shank 10 - :
and the cutting tip 11 can thus only be used as an inside
cutter or an outside cutter. The slot or groove 14 comprises
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two lateral surfaces or faces 29 and a base or bottom 30, as
is particularly apparent~ from Figure 5. The cutting edge 22
lS arranged substantlally~ paralled to the two lateral
surfaces or faces 29 of the ~slot or groove 14. In other
words, the two sldes~ of the~ cutting tip ll bear upon
respectLve lateral surfaces or faces '29 of the slot or groove
The cutting~tip 11 is~providéd with two oblong or
elongated ~holes~2~3~and~24.~ The lower~;~or~rear oblong or
elongated hole 24 can extend~to the~lower or rear énd of the '
cutting;~tip~ and~`thus~form~a slot.~ Respective screws or '~
thre~aded~bolts~lS~or~equivalent~structure e~tend or project ' ~
through~these~oblong~or~elongated holes~23~and~24. The stop ''
or`butt~plate l9 is~ also~provided;with a hole or bore 25
through which~ likewise~ ih~ aforenoted further screw or
threaded~olt~15~extends.
The cutting;tip ll is~only ground at the flank 21
and~;at the~true rake~;26. ~The~inventlve tool or cutter
he~relnbefore descrlbed~and~compris~ing the cuiter shank 10 and
the~ cutting ~tip ll;render~s~possLble -~as is customary - a
positive`or nega'Live rake angle of, for instance, +7 to -7,
as~well as a`flank clea~ance~angls of likewise approximately ''
7o
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~he hereinbefore described mounting and fixation of
tne c~ltting tip l1 at the cutter shank lO has the following
~;~ advartace-: The regrlnding process is substantially
~acilitated and the service life or durability of the tool
for m~c~.ir.1ng workpieces 1S considerably improved.
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T,~1hile~ there ara shown and described present
preferred embodiments of the invention, it is to be
distinc~ understood that the invention is not limited
~-~ there~o, ~ut may~be otherwise variously embodied and ;-
practiced within ~the scope of the following claims.
~CCOR5I~GTY,
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