Note: Descriptions are shown in the official language in which they were submitted.
SOd ~8Z ON X~/XI, vv . vu ~,o~o93~ v 04 09
De~cription
- Broaching tool
The invention relates to a broaching tool, in particular for broaching or cuttin~ of
slots, comprising several disks ~t a distance from one another, rot~ting about acommon axis and having se~rnent-like cutting projection~ on their circumference
side.
Cutting tools ~re known frorn the prior art that have several rnilling discs made of
carbide, spaced from one another and having segment-like projections, with the
projections being disposed around the circumference of each milling disc and
separated from one another by a radial slot.
The high density of cutting segments on the disk circumference ne~essitates a
hi~h contact pressure to force the cutting tool into the material to be broached or
cut, such as brickwork. There are also drawb~cks to the extent that a slot ready to
use is not cut, but instead only parallel grooves, with the m3terial remaining be-
tween the grooves having to be removed subsequently to obtain the required slot.
The problern underlying the present invention is to provide a hroaching tool of the
type mentioned at the outset such that slots can be cut or bro~ched with the least
possi~le effort ~nd in one opèration.
The problem is solved in accordanGe with the invention substantially in that theconsecutive segment-like cutting projections of each disk ~re spa~ed at a distance
that is at least approxirnately equal t~ or ~reater than the re~pective circum-
ferential extent of the prolection.
The segment-like projections of each ~isk are~ in accordance with the invention,arranged relative to one another with a spaoing or intermediate area, said inter-
mediate area enclosirl~ an angle ~ relative to the axis in the circumferential direc-
tion that is at least approximately equal to or greater than an angle ~ that is sub-
stantiaily enclosed in each case by a segrnent-like projection relath/e to the axis in
the cir~urnferential direGtion
s o o q~ OLS - ~a O ~ S Z ~ ~ 181~ ~ ~ + ~ 1 L ~ . ~ o J ~ o
90~ ~8Z ON X~/X~ CA 02202260 1997-04-09
The fact that the segments are arranged relative to one another with interrnedi~te
~reas provides a sumciently large sp~ce between the segment~ in v~hieh dis-
lodged material can collect and can then be removed from the slot by the rotation
of the disks.
The invention is characterized in particular in that consecutive segment-like pro-
jections of each disk are spaced at ~ dist~nce that is at least approximately equal
to or ~reater than the respective circumferential extent of the segment-like proje
tions and in that projections of adj~cent ~isks are off~et relative to one another or
are at least in some areas affset to one another in the circ~mferential dileGlion.
It is therefore provide~ that the se~ment-like projections of each disk ~re ~rranged
relative to one another with a sp~ce or intermediate ~rea, said intermediate area
enclosing an angle ~ relative to the axis in the circumferential direction that is at
le~st approxim~tely equal to or greater than an ~ngle a that Is substantially en-
Glosed in each case by a seyment-like pr~jeCtiOn relative to the ~xis in the circum-
ferential direction, and that the adj~cent disks are arranged oFfset to one another
rel~tive to their projections in the circumferential direction. A better
~utting/broaching effect of the broaching tool is achieved by the tea~hings in ac-
cord~nce with the invention. At the same time, the contact presS~lre ean be re-
duced. In this ~vay, for example, the force required for a broa~hing tool with seven
a~jacent disks each having four segments is equal to the force required for a
cutting tool with two par~llel disks in which the segments are arranged evenly and
closely one behind the other along the ~ircumference.
A further advantage is that the offset arrangement of the disks relative to the pro-
jections in the cirGun~ferenti~l direction me~n~ that the spa~ing of the se~ments in
the ~xial direction ~an be greater than the spa~ing of directly adj~cent n~illing
discs As a result, the groove walls created when the broaching tool penetrates
into the material are broken by the vibration of the ac~jacent disks and can then be
rernoved frorn the slot. This permits cutting or broa~hing of ~ slot in a singleoperation.
The broaching tool prefer~bly has n disks of prefer~bly identical ~esign with n ~ 3,
where each disk cornprises a number x of segment-like projections with x ~ 3 and~here the angle a is at least um,n = 360t(n - x)~ and the angle ,B at most ~Bm;~X = (n -
m. An arrangement of this type provides a broaching to~l that gives optimum~esults as regards both smooth runnin~ properties and cutting effect.
N~ o~S ~da ll~SZ~6 181~ ~+~ L~ 0 ~rSr
LOd ~8Z ON X~/X~ CA r022v0~226~0u~lv997v 04 - 09
A particular embodiment is characterized in that the disks are arranged off~et to
one another relative to their projections in the circ~mferential direction such that at
least two segment-like projections overlap or even completely cover one another
when viewed in the axial direction of the broachin~ tooi. This arranyement ensures
that the broaching tool is to a considerable extent engaged in the material for
cutting or broaching with at least two segments simultaneously.
The projections of the disks can be arr~n~ed offset to one another in the circum-
ferential ~irection such that the se~ment-like projections form a Vee such as ~
wedge shape in a developed view with the disks in one plane. Here the segments
of adjacent disks in the circumferenti~l direction are arranged without or largely
without overlapping in relation to one another. As a result, both the smooth
running properties ancl the broaching capacitles o~ the broaching tool are im-
proved.
In particular, the projections of several disks adjacent to one another and extend-
ing from a common axis form, when the broachin~ tool is viewed from the side, a
closed or largely closed ring. Largely closed can mean here that the ring has
interruptions, preferably at regular intervals.
If the disks are preferably of identi~al design~ they can however be varied in their
length and/or the nu~nber of projections, naturally with an otherwise identical
working radius. In this way a bro~ching tool with, for example, 5 or 7 disks c~ncomprise two groups of different ~isks, with differently desi~ned disks succeeding
one ~nother.
~ccording to a further advantageous embodiment of the milling tool it is provided
that the segments form planes that intersect a plane fonned by the disk at an
angle that is preferably in the r~nge ~e~Neen o 5c ~nd 5.
It must be furtherrnore emphasized that each cutting projection or each segment
has in its direction of operation a r~mp-shaped course, with the respective cutting
surf~ce being able to intersect a circle extending around the rot~tion axi~ of the
broaching tool ~t an ~n~le y with 0.5 ~ y c 2~
It is also provided that the disks have a hole for receiving at least one centering
pin. This allou/s fixing of the required setting of the disks relative to one another.
Alignment of the disks to one another and their fixing can also be achieving by
L O O q~ OLS - ~Ia O ~ S Z C ~ +52~ L ~: ~ l L ~ . 1? 0 ~ ~ 0
80d ~ 5~8Z ON X~/X~ cA r 2 2 0v2 2 6~ v ~lv9v9~7~-g 4 ~ 9
gluing ~ndlor clamping.
To sinlplify handling, the bro~ching tool is designed pre~erably as a g~ng tool.Compli~ted alignment of the individual millin~ disks by the user is therefore not
n~cessary.
Further details, advant~ges and features of the invention are given not only In the
claims ~nd the features they contain - sinyly or in oombination - but also in the
following description of a preferred design example shown in the drawin~
In the dravl~ings,
Fig. 1 shows a plan view of a milling disk,
Fig. 2 Chows a broaching tool composed of milling disks as per Fiy. 1 in a
side view, and
Fig. 3 shows ~ developed view of the broaching tool over 360 in one
plane.
Fis~. 1 shows purely in prlnclple a disk (10) acting as ~n element for a bro~ching
tool (12) desi~ned as a yang tool, the design of which tool is explained in moredetail in Fig. ~.
The disk ~10) has a rnet~llic, preferably lacquered disk-~haped basic element (14)~
frorn whose circumference (1~) extend segment-like projections (18), (20), (22),(24). The circumferential projections (18), (20), (22), (24) are equally sp~oed frorn
one another over the circumference (1~) by interrnediate areas (~ 8), (30),
(32). This is ho~vever not a mandatory feature, and in the circun~ferential direction
the length of the segment like projections andJor their spacing can v~ry.
In the design example ~s per ~ig 1, the disk (10) has ~our projections coverin~ an
an~le 11 = 30~ in the circumferential direction relative to a central and rot~tion axis
(33). The intermecll~te ~reas (26), (28), (30), (32) cover in the Gircumferential
~irection an angle ~ 0, likewise rel~tive to the rotation axis (33).
~he protruding segments (18), (20)~ (22~, (24) are designed as s-lpports for seg-
ment elements (34), (3~), (38), (40). The segment elements (34~, (36~, (38), (40)
8~01~ N;~ OLS-~(I OCSZC~ 181~ ~+~. 8~:CT L8, ~0,'~0
60cl bl~8~ ON XWX,L CA 02202260 1997-04-09
e~entially comprise sintered metal with diamon~ g~ains and are ~onnected to the
segments or projections (18), (20), ~), (24), for example by laser weldiny The
segment elements have a width that is preferably greater than th~t of the ~asic
element (14). Furtherrnore, it is rnade clear using the segment elernent (40) that
the cutting sur~ace (41) rises in the circ~mferential direction, i e the ~egnlent
element (40) has a ratT p-like geometry. The cuttin~ height (41) of the segment
element should however be identical along the entire cutting surface (41), i.e the
length of the segment (40).
The cutting surFace (41) preferably intersects a circle extending from the rotation
axis (33) at an angle r with 0 5 ~ ~ c 5, in particular 1 c y c 2~.
In the tr~nsition area between the segments (18), (20), (22), (~4) ~nd the disk
basic elerrent (14~, indentations (42) can be provided to reduce any notching
eflect in this ~rea
In the ~enter of the disk (10), a penetration such as a hole (44) i5 provided for
mounting the disks (10) on a tool holder (46)
Furthermore, the disk (10) has ~ penetr~tion (48) for receiving a fixing pin (50)
such that during operation of the gang tool (1~) the relative positions of the milling
disks (10) to one another remain secured The disks can also be fixed rel~tive toone another by clamping, gluing or other n~easures.
Fig ~ ~hows a side vie~v of the broaching tool ~12). The ~ro~hing tool (12) sub-st~ntially compri~es the gang tool holder (46) with e hollow shaft end (47) on
which the disks (10) are arranged with a ~pacing d between them To a~j~JSt the
spaGing d, ring-like intermediate elements (~2~ are inserted between the dlsks
(10). The spacing d between the disks (10) ~an be in a range from 2 mm to 6 mm,
pre~erably 4 mm. The disks (10) themselves have a width b in a range from
preferably 1.4 to 1.8 mm, in particular 1.6 mm
An end (54) o~ the hollour cylin~rical shaft (47) has a plate-like closure ~5~) forming
~ ~-shape to~ether with the sh~ft end ~47) ~nd ~ctin~ as the stop for at least one
disk (10) The plate-like dlsk (56) preferably has in its center a penetration for
receiviny a tool such as ~n Allen key for connecting the gang tool (12) to a drive
unit, not sho~vn Fo~ connection with the drive unit or rnachine tool, the hollowshaft end (47) has on its inside a thread (5~), using which the g~ng tool holder(4~) can be ~ttached to a rotatable cirive shaft, not shown in detail, of the machine
~ooi~ ols ~a ocszc~ 181~ ~t+~ 8P:CI ~. tO~O
01~ 8Z ON XWX~. CA 02202260 1997-04-09
tool.
Fi~. 3 shows ~ cleveloped view (~0~ of the broaching tool (12) over 3~0 in one
plane. As the developed view ~60) -~hows, the broaching tool (12) comprises a
total of seven disks whose design is identical in the design example wlth that of
the disk (10) described on the basis of Fig. 1. The disks ~re arranged offset to one
another relative to the projections in the circumferential direction such tha~
segment elements (34), (62), (64), (66), (68), (70), (72) of ~ cent disks forn~ 3
wedge shape. The disks are here arranged such that in the axial direction at least
two segment elements coinci~e or at least overlap. In the design example shown,
the disks are arranged offset to one another such that an end edge (74) of a seg-
ment (34) in the running direction (7~) is followed by at least orle ~ront edge (78),
(80) o~ an ~djacent segment (~2), (64~. It is possible here to have ~ sp~cing be-
tYveen front and end/rear edges that follow one another in the side view o~ the
gang tool
The broaching tool (12~ therefore has on the GirGumferential side fourwedge-likearr~ngements (82), (84), (86), (~8), with each wedge shape extending over 120
The segments (24), (36), (38), (40) forrning one tip of the wedge shapes are
arranged one behind the other in tl1e circumferential direction, in each case ~t an
angle of 90~. The wed~e shapes (82)l (~4), (~6), (88) are arran~ed nested, with
those segments forrning the tip of the wedge sh~pe~ having the s~me ~ngular
position in the developed view (~0) as the end se~ments (70), ~7~) of a preceding
wedge sh~pe (82).
The embodiment shown in Fig. 3 is only ~ preferred embodiment, without thereby
resulting in ~ restriction o~the invention. The bro~ching tool c~n also run against
the direction of the arrow (76).
Arr~ngements with 3 or 5 or g disks are of co(~r~e also conceivable. The number
andlor length of the projections ~an ~Iso v~ry from disk to disk. In this way. outer
disks can have more cutting projections than inner clisks and vice ~ersa. Also,
~or-secutive disks can vary in respect of the number and/or length of the c~in~
projections.
However, the projections should be distri~uted evenly over the circumference of
each disk The arrangement with seven disks shown in Figs 1 to 3 has proved
particularly ad~ant~eous.
.
010[~ N~ IN:I:IOl.S'~ l OCSZS`ff 18113 ffl+8 ff'v:f:l L ff . IO~ffO
