DIAMOND/BORON NITRIDE COATED EXCAVATING TOOL CUTTING INSERT

ELEMENT DE COUPE DETACHABLE RECOUVERT DE DIAMANT/NITRURE DE BORE CUBIQUE, DESTINE A UN OUTIL D'EXCAVATION

English Abstract

ABSTRACT OF THE DISCLOSURE
A diamond/cubic boron nitride coated low energy cutting insert for an
excavating tool. The insert includes a generally conical tip portion, an
elongated intermediate portion, a shoulder and a contact surface which attaches
to a supporting surface of the tool body. The intermediate portion of the insert
includes a concave surface portion and the coating is provided on the tip portion
and optionally on the intermediate portion and the shoulder.

Claims

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WHAT IS CLAIMED IS:
1. A rotatable excavating tool for breaking hard material,
comprising:
an elongated tool body having an end with a diameter and a supporting
surface;
a cutting insert of hard metal having a tip portion, an elongated
intermediate portion and a shoulder, the tip portion being generally conical in
shape, the should having a diameter substantially larger than the maximum
diameter of the tip portion, the intermediate portion being integral with and
extending between the tip portion and the shoulder so as to define an abrupt
transition from the tip portion, the intermediate portion having a maximum
diameter which is substantially less than the diameter of the tool body end, the
intermediate portion including a concave surface portion extending radially
outwardly between the tip portion and the shoulder, the shoulder being
integrally joined to the concave surface portion, and the cutting insert having a
rearwardly facing contact surface attached to the supporting surface of the tool
body; and
a wear resistant coating of material harder than the cutting insert, the
coating being on at least an exposed working surface of the tip portion.
2. A tool according to claim 1, wherein the coating comprises at
least one layer of diamond and/or cubic boron altride with or without one or
more non-diamond intermediate layers.
3. A tool according to claim 2, wherein the coating comprises a
single layer of diamond.
4. A tool according to claim 1, wherein the concave surface portion
has a constant radius of curvature.

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5. A tool according to claim 1, wherein a distance (a) from the
abrupt transition between the tip portion and the intermediate portion to the
radially outermost portion of the rearwardly facing contact surface of the
shoulder is larger than a distance (b) from the abrupt transition to the axiallyforwardmost portion of the tip portion.
6. A tool according to claim 5, wherein a smallest diameter (d) of
the concave surface portion is smaller than the distance (a+b) from the axially
forwardmost portion of the tip portion to the radially outermost portion of the
rearwardly facing contact surface of the shoulder.
7. A tool according to claim 1, wherein the coating only covers the
tip portion.
8. A tool according to claim 1, wherein the coating completely covers
the tip portion and the intermediate portion.
9. A tool according to claim 1, wherein the coating completely covers
the tip portion, the intermediate portion and the shoulder.
10. A rotatable excavating tool for breaking hard material,
comprising:
an elongated tool body having an end with a diameter and a supporting
surface;
a cutting insert of hard metal having a generally conical tip portion, a
shoulder with a diameter substantially larger than the maximum diameter of the
tip portion, an elongated intermediate portion integral with and extending
axially and radially between the conical tip portion and the shoulder so as to
define an abrupt transition from the tip portion, the intermediate portion having
a maximum diameter which is substantially less than the diameter of the tool

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body end and the intermediate portion including a concave surface portion, the
shoulder integrally joining the concave surface portion, and
the insert including a rearwardly facing contact surface attached to the
supporting surface of the tool body; and
a wear resistant coating of material harder than the cutting insert, the
coating being on at least an exposed working surface of the tip portion.
11. A tool according a claim 10, wherein the coating comprises at
least one layer of diamond and/or cubic boron nitride with or without one or
more non-diamond intermediate layers.
12. A tool according to claim 11, wherein the coating comprises a
single layer of diamond.
13. A tool according to claim 10, wherein the concave surface
portion has a constant radius of curvature.
14. A tool according to claim 10, wherein a distance (a) from the
abrupt transition between the tip portion and the intermediate portion to the
radially outermost portion of the rearwardly facing contact surface of the
shoulder is larger than a distance (b) from the abrupt transition to the axiallyforwardmost portion of the generally conical tip portion.
15. A tool according to claim 14, wherein a smallest diameter (d) of
the concave surface portion is smaller than the distance (a+b) from the axially
forwardmost portion of the tip portion to the radially outermost portion of the
rearwardly facing contact surface of the shoulder.
16. A tool according to claim 10, wherein the coating only covers the
tip portion.

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17. A tool according to claim 10, wherein the coating completely
covers the tip portion and the intermediate portion.
18. A tool according to claim 10, wherein the coating completely
covers the tip portion, the intermediate portion and the shoulder.

Description

'~4 10/20 10:50 1Z~48 20 2O108~ SANDVIK PATENT ~ GO~LING IZl003/Oll
` ` 213~396
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DL~MONDJBO~lON NX~R~E COA~
EXCA~ ~)OL Ctm~G I~
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pEdic~on i~ rdated to y pl~atlon S~rlal No. 07/708,058, fLbd
Mlly 301 1991 lnow U.S. Pa~ No. 5,161,8S9), A oon~nu~on of app~ on
Ser. No. 07!517,~23, a~ y 1, 1990, now abando~ed, which it a
oon~nuati~n of ap~Jlca~on Ser. No. 06/586,818, fi.W M~i~6, 1984 (now l~.S.
Pat. No. 4,938,538).
Iho prosult In~ren~on relato~ to a ~l hr b~ or au a~ of ~d
ma~, SUch ~s ~t, compd~g a ~401 hiy a~ ~
~to, for ~n~ancc by bs~g. Tho c-lt~ h fonned wi~ a gcnerally
OOMCal tlp pO~ d p~ with a ~lild wl~ Dbl~det to ~t
4~n~t a suppo~ surhc¢ ~ tho tod body.
Tbe pu~e of ~ to p~ovid~ a wear~ ~ant t4~1 of the
tb~t tho ~lc ~ low that ~he a~n~ L~e~t ~11 ~ot low~ ovan dudn~ worldng in :- .
~o aooom~an~ dtawings, h wh~ o~e em~ i~ sbQwn by way of
15 oo bo unt~Qood tbat ~ em~od~t i~ orly il~ vo of tbc
n~tlon and th~ va~iow m~ ~eo may bo n~do wl~n ~o sc.ope
: ~ ~ of ~o ~
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~ . . .
~ ~tiO~ ~cav~a~ tool for
bre~ ~d ma~, oo~g ~ don~od tool body h~.a~ ond wlth a
di~ r and a ou~ u ~ a ~uttl~g ~t ha~ine a war rosis~ant lay~r
on an a~poset wo~ ~u~ ~eof, tho i~ t bdng of b~rd mep~ g
~p pordan, ~ do0ga1ed in~m~hb po~ ~d a ~ould, ~# tip pordon
be~ ~e~y ooDic~ he ~houlder h~vin~ a dhmoter subst~lly
~: larger tb~n ~he m~dmum dialDebr of tho ~p po~oa, tbe ~nlenned~ por~on
.
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'1~4 10~20 10:51 ~H 2H 2~1U8~ S~NDVIK PATENT ~l~ C'OWLING la~Où4/014
` 213~3~6
.
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bdn~ inbgIal wi~ and ¢xtendsng bctwoen tho ~p por~on an~ ~ should~r so as
to de~o an ab qpt transitlon fro~ o ~p po~on, tho interm~o portton
having ~ ma%imum diametor which is ~ubsta~ally 1~ tban ~o diameter o~ the
tool body end, the ~nte~med~ato ~oa induting a concave s~aco p~on
e~cto~ldine r~laUy outwa~y bohve~ Iho tq~ por~n ~nd ~e s40uldor, ~4e
shouldo~ be~ î~eua11y joino~ to the wDca~o ~ ~r~oo, ~nd ~o iAsolt
including a ~anv~y ~acing oonta~ ~ a~achod t~ por~ne ~ce
of ~e tool body. ..
~ ~v~n~ ~Iso p~ida a ~vo~r ~nt ro~lc e~ng lool for
dbme~ and a supporang surhco, a cuttin~ ~sett hn~ng a w~ ~wistant
coa~n~ on rn o.~pwet wod~ surS~ roof, tbo ~t bdne of h~rd metal
g A gea~y c~ p pOa~OII, t ~houlder ~ a dianNtor subs~ally
l~r ~in the ma~{mum dumet~ of tho dp por~n, ~ elongokd intenned ate .
por~ int~ wl~h ~nd ~ua~ a~y aad ~dially botw~ tlio oodca1 ~p
and tho sho~dder, ddlnin~ au ab~ c g~norall~
conk~ dp p~, ~d h~iins a m~aum d~ wh~cb is subslan~a11y l~ss
tba~ dle diam~ ~ U~c tool body ond, thc ~t~ p~on oompnsing a
coaca~ ~c po~, ~c thou~ _y~ ~ CwuaYe ~e ~ ~
pofflou, ~d a r~w~ly *~ w~ urfaco a~od to lho ~g
of ~e tool body.
~: ~ to ~ious fo~s ~f t~o Jn~do~"ho we~r rcsist~nt coa~ing
caQ bo of d~d ind/a~ cubic bor~n ~ltrite wi~ out ~o or more
}nt~tc ~amond lay~a ~uch as ~, I~C or ~. Tho concavo surfaco
po~don c~q h~re a ~t ~dlw of cuN~re. Ih ~, ~e dis~nce ta)
to tho ~lly outumost pordon of ~o r~y f~ng cont~ hcc of ~o
sho~der can be la~er Ihan ~e dis~ om ~o ~upt ~laon to tho
a~dally ~o w~ostp~ of tlie tippo~on, Thc sm~ dl~ r (t) of the
~o ~ pordoa can bo ~1~ tha~ the di~o ~a tb) f~ e a~lly
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'~4 10~20 10:51 ~40 2~ 2010811 9AND~'IN P~Tf~ ~ ~0WLING IZlOn5/014
. ' '`'.~;
for~ardmo~ po~ of tho dp po~on to ~o ~adislly ou~mo~ por~n of t~lo
~y faci~K oonhct surhco of the should*.
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~IG. 1 show~ a slde vlcw, p~iy h rec~ , of pdar ~ 1401 fo~
brealdng hard ~tedal;
PIG~ 2 ~ side view, p~ly iA ~ a~r pdar ~ tool;
p
FIU. 4 show~ on ~ eDIargtd ~oab tl~ cun~ h~ ~ th~ ~ ~n ir~ . .
P~G. 3. t
. ~
be v~ fignDos hav~ gl~n ~e samo
Tool~ o q pc ;n q~os~n ~e u~y mountod ~ota~blj ~n a tool
older, wh~ch ~ ~m ~s ~dbd to a~ tw~adng n~, wch as a road
pl~llU _ar a ~in~ m~ Duo ~ ~ ro~o~ d4 tool Is sdf~
~OD~. l~o ma~no ~t be of tbo type tis~od in
~:~: U.S.Pal~tNo.4~12,~5S,tho of wblc~ eby
~a~g ~f ~ ~t m~ for l~ce for
g h ~o~d ~It (m~ ob ~o u~od o ~ q,pe Jbow~ 1n Fla. 1.
: . This ~*a ~ a ~aol boty 10~ of ~teol snd a cu~lng i~ort llA of h~
wbl~ ~ tost ~t a ~ co l4A on
~i body l~ IDe rar ~ J~u*co 20A o1he ~r l3~ i~ b~zot:to
lho supp~ ~ce 14A. ~ho cut~ l~ert llA iJ po~dod ~th ~ coniall
lSA which 1~ loated b~woen Iho ~p ~d~ 12~ and the
shoulder 13A. Tl~ p~n lSA _ tbc portloA of ~c tool body lOA
tl~e cut~ne ins~ tlA *om ~ w~r ~ would ~awo t~e cutting
. ~ IDsert :llA to ~a ~090. Whal we~ re~t m~ 4 e7~0t, ~r ins~qco
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'~4 ln~20 10:~2 2S4~ 2~ 2~108~1 _9~.NDYIK PATENT ~ GOWLING lzloo~5~ol4
.,
duri~g mi~line Ul pourod asp)~alt, the ~p po~tio~ 12A become- blunt~ended upon
some wear of tho cut~ng insert llA. This wear Increase~ ukod cutting
*r~C, When millhg in poured asphalt, the inc~aso of thc ~oqul~d cu~
force snieht evon havc the ~e~ult th~t tbo mad pl~n~ns machlne doos n~t manage
Ono way of docre~ tl# cu~ urc r~ for worn ~ols wo~d
be to use a t~l of th~ ~ype shown ~n ~G. 2 ~ce tbo al~ insort 1 lB has a
smalIer di~lm~ ~an the cuttinl~ in~t llA. Howw~, ~his shou1d mam that
tho po~on 16B of ~ tool body 10B su~rou~ ~e cu~ insut llB ~pidly
would be ~bradod, th~y c~n~ t~e cutthe ~nsert llB to ge~ looso. Thus,
cut~ serts of ~ tJ~pe sho~n in FIG. 2 are s~t4~b f;: r us s ~olely where ~o
hard m~ de~nes tho ~ o~ ~e lool, for Inst~noe m~lling in conc~to.
Accotdin~ to thc inven~oa, a low ~er~y anac~ tool is Qrovidod wbich
includes a w~ar resis~nt co~tin~ on a culting ~t ~ the form of a ca~
whereln the c~ i~ of a ma~l ~ than t~o i~ For ulstance, the
iasort ~ bo a cemalt~ d d~ co~ ca~ bo dhmond and/or cubic
boro~ n~ide. 'Iho coa~ am bo nppli~d on the c.~posed surbce of dle insort
with or wl~out ane or moro Intermdi~ non di~mood layes~ . TiC,
te np~ ~ro~ ure~/ElP) or olher oonYen~ al te~bnique. The
wear ~ coatin~ ~d int~c Layen c~ each ~vo ~ ~nes~ of
iabout ~.O to about~mi ~d the tot~l t~ of the c~ can reac~l
S~m or more d~d~ng on ~ho ~i of each layer ~nt numbcr of layers.
For ~n~:c, the oo~ c~n i~cludc so~ ~ays of d1arnond ~ ated by
non dismond b!~ers. ltT.S. Patent Nos. S,154,245 ~ ,707,384, ~e
di~closures ~ which a~ he~oby ~d by refce ce, tis~oso seve~
diamond a~n~ tecbn~ques whi~h a~ bo usod hr yply}ng tho ~oaing.
l'ho w~ar rosis~nt coati~ ~ows the gcome~y of the ~ to be
main~incd for a lo~ier ~mo th~ dciq~ ~e amount of dust cr~od by the
tool, reduciag ~o cuttin~ forces, reduclnlJ fotces a~ng, on ~he o~ol, reduc~
heat cre~ed by ~o cutting ~ of ~e tool ~t reducinl~ ~e p~ iq~ of
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'1~4 10~20 10:52 'ZS4ti 2~ 2~1118h SANDVIK PAI'ENT ~ 1 GnWLI~ b~10()7/014
.
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spa~l~g w~cb could oth~sc ocalr tuo to ~o conlact b~nveon ~o comon~
carbide ~ol and ~c ma~ acaYated.
A~ ~hown ln ~GS. 3 ~d 4, ~c cutllng inse~t 11 in a too~ accordlng to
tho Lnven~on is provided wi~ t~odhto portlon 17 behveen Ihe ~
po~on 12 and tho sboulder 13. Tbo into~ le pO~Q compd~ a con~a ~e
por~o~ 17~. Due to ~ intennodi~to S~co por~on 17, tho requ~ot ¢ut~ne
forco is m~n~ot low cven whon ~ o~ 12 becomes worn, sincc
~ s~zo ra~i~ ~ea~l~ the ~m~ as ~e ~p w~ daw~
steea ~n tllo tool bod~ 10 ~ t
p~n~e abras~on. ~is pso~ion ~s ps~d by ~e coAcave p~on 17' and
thc ~houlder 13.
The we~r resis~ coating 60 can bo appDed on ~ outer ~ of ~ ~ -
tip 12, ~o intonnediate portion 17 andlor dlc ~ 13 ln a~y ~le
pa~ whic~ completely cove~s or pa~ly co~ ~c worldD~ surface.
don ~rl bcated sd~acent tD thc d~ p~OQ 12. ~ tl~ nbodimcnt, ~e
d~ce ~ om Iho t~nsi~on 18 ~otweo~ p ~n l2 and d~e .
int~te po~ 17 to ~e ~di~lb ~most portion 19 of ~ho sear coQlaCt
surfi~c 20.Qf ~ d q~ 13 ~s l~ger ~ tho ~ ~b" firom ~N t~nsi~on
18 to th~ a~dally fon~rdntost por~n of ~e ~p pordon 12. Tho ~ar con~
surf~ce 201s ~tendod tO ~ost a~Dst tlu ~ surfw 14 of ~e k~ol body
0.
F~, In ~c illu~Sod o~bodi~ent~ ~o s~t.diasnder ~d~ of the
~Ye po~aA 17I is smsllo~ 1~ thc Aq~ of ~ ~bove-defined di~ta~ces ~a"
and "b~. ~ con~v~ p~ 171 i~ p~dod ud~ A codnt ~S of
Clm~ WhiC~ Qr ti~l 1,$ d bUt bi~r th~ O,S d.
~ tall~dalb tO ~e u~ot pa~ 171. .
..
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~ `;`'~" ~"' " ' ~' ~ '` ' '

'N~ 10~20 lO:SJ S4~ Yi~ YOlO~la 9~ . (;IJWL~ IG ClloOq~014
~ . ~ . ~
~ ~e illus~d embodime~t the cuUlng ~nsort is peovidcd ~vith ~ rearpordon pr~e~ns lea~y *om ~o sho~d 13. ~e cnd~ co of ~
yor~ ~ ~anar. n n~ght, howev~r, b~ ~ccesscd, fo~ t cquld bc h~-
sphodcal ar o~ ~ Senal W~ lus~ed 1~ Swcd-~ Pat~t ~p~io~on
No. 8400Q69 0. Thc botto~ of d tecess ~t rost ~ai~st ~ y
shapd ptotruslon on tho tool body. ot, a~t~vely" ~e rooo~s m~ebt pr~lvlde a
ca~r. *, .......
a fb~or m~ on, tbe cu~ ~n~ misht bc m~te wi~out a
~r pr4ioodo~. The ~ear ~d su~ of dle cutd~ iose~t, ~c tho uld surfilcc
of Ihe shoulder, ant tbo ~ f~t surhce oOE Ihe tool ~ody mi~t be
desi~ed ~cor~ng to any o~ the abovo iltema~.
th~ pre~ t ~v~t~ h~ beo~ do~ot 1~ ~ wl~
p~f~od cmbod~ theroof, it v~l be ~pp~ by ~! ~ ~ ~ art
~lut addi~o~, modlfl~os, sub~tuti~s, a~d dde~o~ not ~ifia lly
da~d may bo m~de ~out depa~ md ~ of ~e
i~v~all u dofi~ed in th~ ~pendod cl~i~s;
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Representative Drawing