Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~ ~'' 2 ~09~72~
TITLE
CENTRAL DISC MADE OF FIB~E-REIMFORC~D P~ASTIC FOR ~ -
CIRCULAR-SAW B~ADES AND/OR ABRASIVE CUTTERS
The present invention relates to a stock
biade for circular saw blades and/or abrasive
cutting discs, comprising a circular disc body '
~nlch consists at least partially of a ibre-
reinforced plastics material.
'',:-
The invention further relates to a methodand apparat'us for producing the stock blade.
Stock ~lades of this type are'used in
particular for circular saw blades and/or abrasive
_utting discs provided for ~orking stone,~ ' '-,~ `,
peripneral, in mo3t cases, diamond-tipped cutting
e,omponents (cuttiny segments) being secured on the ~;~ , ,;
outer periphery of the stock bl~de. For given
applications very large stock blades having~a
blade diameter of up to 5.00 m are required. In
ordsr that the weight of the stock blade is Dot
too great with large blade diameters of this type,
attempts have already been made to manufacture the .,
disc bodies from plastics material, in particular '~'~",'''
a glass-fibre reinforced plastics material, or
some other composite. However, considerable
problems were encount,~red in this respect to the
o
effect that plastics ma~erial stock blades o this
type are unstabie or labile and become distorted
in operation when acted upon by forces resulting -,
rom ro~ation and as a result oi heating-up owing
to material stress~s. This leads to poor operating
prop~rtie~ and even to poor quality machining when
' ths saw blades are in use. In extreme cases ths
distortions occurring might even result in the,
blade~being destroyed and/or the respective
workpiece being damaged. Hitherto these proble~s
could not be resolved satisfactorily such that
plastics material saw blad,eslcould not yet ~e`used
for all applications.
The present invention is therefore bas0d ;~
on the oDject o~ eliminating the'problems
described above and providing a stock blade of the ,~
lr~ ally mentioned ~type which ensures optimum ;
,operating properties and machining results in
practically aIl operating conditions, and which ',~
also has a long useful life.
:::
Furthermore, a method and apparatus for
producing the stock blade according to the
~ invention are also to be provided.
; In a'ccordance with the invention this
ob ject lS achie~ied by the features of claims 1, 28
.. ~:.. ,. ,, ,,.. , , :. ~
~.`, 2~725
and 39. Advantageous urther developments o the -,
invention are contained in the respective
subclaims dapendent on the latter. ,-
- "
The stock blade according to the
inveDtion is tnus characterized in that the fibres ~ ~ ;
are embedded in the plastic,s material so as to be
oriented at least approximately rad,ially ~
relative to the circular shape of the disc body -
and uniormly distributed over the periphery of
the disc body. As a result of this advantageous
.~ .
arrangement, the stoc~ blade~according to the ,~
invention has the same mechanical properties in
every radlal directionj so that it can practically
be said to be "radially isotropic". The stock
,. ...
blade is cnaracterized by optimum operating
pro erties in almost all operating conditiono, low
weight and a long service lie (durability). Thus, i~
: ~ ,.,, : ~ ~. .
in addition to the substantially radial fibres,
~urther i'ores could also be disposed in principle -, -
~such that they run in the perlpheral direction or ,~
along chords, however it is has emerged that for
; the majorlty o~ applications optimum properties
can be achieved with ibres which are at least
approximately radial alone.
: ~ .
- In principla, any fibrous material could ~ ~ ' -
be used, as could glass fibres. However; it has
~.; 2~72~ ~
proved to be particularly advantageous to use a
carbon fibre material, the so-called "highly
rigid" (HM) carbon fibres being most suitable aq
COmpd~ed Wlt~ "hlgh tsnsile'' (HT) carbon fibres,
since - a~ ~e~ts have shown - with a fibre content
of approximately 65 volume % the corresponding ~;;
plastics material (abbreviated to ~M-CFK) can
attain a modulus of elasticity of approximately ,~
260,000 Njmm (in the fibre direction). In ~
comparison thereto, steel has a modulus of ~ ,
elasticity of only 710,000 N/mm2 which means that
the elastic properties of the stock blade
according to the invention are even better than
those of a stock blade made from steel.
s a result of the orientation of the
fibres which is at least predominantly radial -
owing to ~he geometry - the pla`stics material of
the disc body has a flbre content which decreases
in the radial direction from the interior to the
exterior, which has an unexpected yet advantageous
~effect on the mechanical properties. The average
fibre content is thus 30 to 80 volume ~, in
::
~ particular approximately 60 to 65 volume ~
: : , , : .
It is further advantageous if the fibres
are embedded tightly in the plastics material,
i.e. under a given. at least slight, tensile ~ -~
`` ~` 2~7~
stress whicn lS identical for all the fibres. As a
result thereo~, the fibres can exert a supporting
force on the plastics material in an optimum
mdllnar. ,n ~nls connection it is essential for a
good, matarial-locking bond to be ensured between
~ne fibI-es and the plastics material. This is
achieved in particular with a plastics material
based on a low-viscosity synthetic resin, since,
when a resin of this typ~ is mixed with the
ap~ropriate hardener, the trapping of air can be
almost completely avoided, such that as a result
thereof, and also owing to the low viscosity,
optimum wetting of the fibres with the plastics
material can be ensured. ~;
t is furthermore advantageous for the
machallical properties of the stock blade according
to the inven~lon if the latter comprises two
axternal fibre layers containing the fibres and a -
central layer which lies centrally between the
above two layers and is connected to the plastics ;~
material in an at least material-locking manner.
~s-efara~ly in this connection a plurality of fibre
layers are disposed one above the other in each
fibre layer in a direction perpendicular to the ~--
plane o~ the stock blade disc. As a result
,
thereof, the aforementioned fibre content is
attain~d, the fibres lying closely adjacent one
2 ~ 2 5
another. The central layer preferably comprise~ a
~bre-free p1astics material but can also be made
of metal or some other suitable material.
~ , .
In order ~o be able to secure the
pariphelal cutting segments, which are to be
j soldared for some applications, to the plastics
material stock blade according to the invention in
-':
a particularly simple manner, the disc body
comprises a segment carrier~ring of which a - ~ -
connection section is connected in a material
and/or interlocking manner to the plastics
mater~àl and is in particular embedded, and of
whioh a ratalning section extends radially beyond
tha outar periphery of the diso body. Cutting
segment retaining devices, connected to the
cutting segments, can then be secured on this
retaining 3eqtion. As a result thereof, the
.
c~tirlg segmants can still be soldered, namely
:~:
onto the cutting segment retaining devices which
in turn can ~e connected to the 5egment carrier
~ ring in any manner eg. by adhesion or by means of
;~ 3craw or ri~et connectionsO A plurality of
alternative embodlments for this means of
connecti~on will be described in further detail
~below in the subsequent description of the
:: . - , ,- ~ . . ~
Figures. ~
:~ ` :, ~ :':
-` 2090 1~
The method of producing the ~tock blade
according to the invsntion is charactarized in
that firstly fibres are disposed in at least
approximately radiai alignment - relative to the
circular shape OI the stock blade - and are ~
distributed in a layer-like arrangement uniformly ;
over the periphery; and in that the fibres are ~ :
embedded in a plastics material whilst being . . ; ~:~
h -d
s ape . ~.
An apparatus for producing a stock blade ~ :
~ ~ ,. .<.
according to the inventlon comprises a plastics
~aterial pressing or injection moulding tool
having a~shape corresponding to the stock blade
. . , ,.,~ , :
and is thus characterized by a plurality of.
securing pins distributed over the outer periphery
of the tool. These securing pins are used to
,,; ;
arrange the ~ibres in the manner in accordance
with the invention in that the fibres are wound ;~
.: j .
about the securing pins in such a way that they `~
are oriented at least approximately radially. Thus
~ ,
peripheral securing pins can be provided
exclusively, between which the fibres are in each
case secured so that they extend at least
approximately diagonally, or at least one
:. . .
additional securing pin can be provided, disposed .
in the inner are~, the fibres then being wound in
,
each case such that they-extend between the outer
:: .
:
.. ....... .. . .. . . .
, ~ 2 ~ 7 ~ 5
securing pins and the inner securing pin (or pins)
at least approximately rQdially. The subsequent
description of the Figures contains some concrete
exampl~s o~ givsn winding technique~ and securing
pin arrangements.
~) In the following the invention wiil be
described in ~urther detail by way of example with
reference to the drawings in which:
Figure 1 shows a plan view of a stock blade
according to the invention; , -
Figure ? shows a cross-section of the stock blade,
on a slightly larger scale than Figura 1, along ;
the line II-II in Figure 1;
,/ , ,':' :~
Figure 3 shows a section along the line III-III in
Figure 2 extending through two different planes on
a scale corresponding approximately to the scale
in Figure 1; ;~
~ ~ .
Figures 4 to 7 show enlarged sectional
illustrations of the outer peripheral area of the
,
stock blade, i.e. area A in Figure 2, in
alternative arrangements with respect to the
segment carrier ring and fùrther illustrating
cutting seament holding devices;
2~.9~7~3
Figure 8 snow5 a plan vlew of part of a segment
_al ~ ~ 'r i lng ln an advantageous arrangement;
,; ,':
~igure ~ shows a plan view of a further embodiment
or a stock blade according to the invention;
Figure 10 shows a cross-section of the stoc~ blade :,:
aiong the line X - X in Flgure 9; ;~
Figures 11 to 1~ show cross-sections through the ' :
nner area or the stock blade in different
arrangernents OL the mounting(flange togecher with ; -
_iamplng dev i ces and a coolant supply; .~ '
~igures l5 ~o l9 in each case show greatly
~impii~ied, ~chematic plan views of an apparatus
according to the invention for producing the stock . ~ ;
blade, illustrating the production method
according to the invention, i.e. in particular :
varlous fibre winding techni~ues; and ,~
Figure 20 shows an enlarged semi-radial section of
~ne ~tock blade il:lustrating the production method .
.
according to the inveniion.~
In the dlfferent Figures of the drawings ~:
;dentlcal ~rts and components and those having
: ident~cal e~fects are always designated~with the
~-i; 2~725
same r2f~rellce numbers and are therefore generally
only ~_scribed once.
AS emerges rirstly from Figures 1 to 3, a
c~rcuiar saw stock blade 1 according to th_
invention comprises a circular disc body 2, which
in principle is produced from a plastics material
6 (Fig. 2) reinforced with fibres 4 (Fig. 3). In
its lnner surface area the disc body 2 has a .
central mountlng opening 8 and preferably a ;;~
thickened mounting flange 10 wnich surrounds the
latter and in this embodiment is formed thereon
Lntegrally, i.e. lt likewise consists of the
" :.
piaetics materlal 6. ~utting segments (not
ilu~ra~ed) can be secured on the outer periphery
12 or the disc body 2, for which purpose the disc
~dy 2 is advantageously connected to a segment
carrier ring 14 which will be described in further
detail below with reference to Figures 3 and 8.
As is shown~in partlcular in the
schematic lllustration in Figure 3, it is provided
in accordance wlth the invention that the fibres 4
~ are emD-ddad in the plastics material 6 such that
; they are oriented at least approximately
adial iy - relative to the circular shape of the
disc body 2 - and;uniformly distributed-over the
~-rlph--ry o the disc body 2. The term "~at least
- ! 2 ~ ~ ~ 7 ~ ~
",:
12 -
approxlmaleiy radialiy" in this connection is to
; ~a in~etprbted in such a way that the fibre~ 4 can
also be disposed on eccentrically extending
-noràs, these chords, however, having to run as
close as possible past the centre point of the -
stock blade 1, at least through the area of the
flange 10 ("quasi-radial" path; c~. in this
respect Figures 15 to 20 also). In this connection
additional fibres could also be provided in
addition to these "quasi-radial" fibres 4 in the
peripheral directlon or along chords (not
illustl-ated) sxtending further away from the~
centre polnt (externaily of the ~lange area). In
~ddition, reserence should be made to the fact
~that the fibres 4 are actually disposed in a far -~
~ore compact manner than could be illustrated in
Figure 3, far which reason Figure 3 is only to be
regarded as a schematic illustration of the
orientation of the fibres. Ho~ever, this Figure -
shows clearly that the "compactness" of the fibres `~
4, i.e. the fibre content in the plastics material
,
6, ~ecreases in the radial direction from the
interior towards the exterior. The average fibre ~; -
cotlterl~ lrl accordance with the invention is thus
30 to 80 voiume ~ and in particular approximately
uC to u5 voiume ~. The fibres are stiff, i.e.
::: . . ~ ,
un~er at iea~t iight tensile stress, embedded in
rhe pia3tl-s material 6 and~preferably consist of '~
7~
a highiy rlgid carDon fibre material (so-called H~
carbon ibres) resultlng in a HM-CF~. A self-
hardening multicomponent material based on a low-
visco3ity synthetic resin is preferably used as
the plastics material 6.
~ , ' "'
As emerges in particular from Figures 2,
4 to 7 and 20 respectively, in accordance with the
invention the fibres 4 are disposed in two layers
1O and -l8 on either side of a central layer 20 ~ :
d~sposed centrally between the latter. For the .
saka of simplicity, the fibres 4 are not
illustrated in Figures 2 and 4 to 7. The central
layer 20 is connected in an at least material~
locking manner, optionally also in an inter- ~;
locking manner, to the plastics material 6. In
order to interlock the central layer 20 can have
passage openings (not illustrated) which ar~ then ~-
penetrated ~y the plastics material (so-called
"through-connections"). Preferably there is
disposed within each fibre layer 16, 18 a ;
plurality of fibre layers-such that they are
superimposed in the direction perpendicular to the ~ -
plalLe of tne disc. This is shown schematically in
.
~igure ~0 in particular.
As a result of the arrangement described
hi cherto in accoraance with the invention, in ~ `~
7 ~ ~ :
14 ~:
~cidi~iGn co extr~mely light weight and good
durability the stock blade 1 has very good
n,ecnanical properties which advantageously are
identical in all radial directions ("radially ~ .
sotropic"). Thus the stock blade according to the
invention has a remarkable modulus of elasticity :
of appro~imately 260 000 N/mm2 in the direction of
the ~ibres.
In the following the abovementioned ~ :
sagment carrier ring 14 will be explained in
:~
furtnar detali wlth reference to Figures 2 to 8
anci r lyul - 20 . ~his sagment carrier ring 14 :
comprisas an inner connection section 22 which is -:
col~n~_tad ln a material and/or lnterlocking manner
to the plastics material 6 of the disc body 2. In ~ ~:
particular the connection section 22 is thinner
than the disc body 2 and is embedded in a
material-locking manner in the plastics material ~.
6. The segment carrier ring 14 in addition
comprlses a retaining section 24 extending . :~
radially beyond the outer periphery 12 of the disc ;~
DOdy ''. Lhe segment carrier ring 14 can
adyantagaousiy be in the form of a circular disc
rlng GL which the inner peripheral area rorms the ;~
connection section 22 which is embedded in the ~:
~la-L~o~ m~Le~lal o of the disc body 2 such that :~:
L surrouncls tr.e periphery of tne centr l layer ~;~
7 ~ 3
20. Thus the connection section 22 preferably has
passage openings 26 which are penetrated by the
plastics material 6 (cf. in particular Figures 3
to 7), such that advantageously there is a
material and interlocking connection betwaen the
segment carrier ring 14 and the disc body 2. As
Figure 3 further shows, the segment carrier ring
14, in the orm of a circular disc ring, .
advantageously comprises radial expansion slots 28
: , ,
which are distributed over the periphery with open ~ :
edges open in the ràdial direction in each case, .
preferably one expansion slot 28 open at the inner
edge and one open at the external edge being :~
~disposed adjacent one another in eaGh case. These
expansion slots 28 in each case lie between the
passage openings ("through-connections") 26
penetrated by the plastics material 6.
As an alternative to the segment carrier -
: ring being arranged as a circular disc ring, it is
: also possible to use a circular disc-shaped
filling member which has a diameter of a size such
: that the outer periphery thereof projects ~ s
~ ~ outwardly over the outer periphery 12 of the disc
- . ~
body 2. This means that the segment carrier ring
14 is formed by the outer peripheral area of this. :~
filling member forming the central layer 20. This . .
embodiment is shown in Flgure 20.
7f~,S
",
16
'
The segment carri~r ring 14 pre~erably
consists of metal, the entire central layer 20,
i.e. the filling ~ember forming the latter,
evidently consisting of metal in the arrangeme~t
which is integral with the central layer 20.
!
According to Figures 4 to 7 cutting
segment retaining de~ices 30 are secured or can be
secured to the segment carrier ring 14, i.e. on
the retaining section 24 thereof, distrihuted over
the periphery, for which the,following different ~ ;
pO5S i bilities are provided. ~
`:~
According to Figures 4 and 6 the outer ;~
retaining section 24 of the segment carrier ring ~-~
14 is slightly thinner than the disc body 2. The
cutting segment retaining devices 30 in this `
connection have a substantially U-shaped cross~
section with a transverse bar 32 and two parallel
legs 34 which engage over the retaining section 24 ;~
of the segment carrier ring 14 on both sides.
These cutting segment retaining devices 30 can be
oonded to the segment carrier ring 14 and/or held ~-
by means oi screw or rivet connections (not - ~
illustrated) dispoeed iIl the vicinity of the legs ;
34 engaging over the retaining section 24. In
accordance with Figure 4, the retaining section 24
,: -.,''
.
2 ~ 7 2 ~
17
Lmmediately ~ollows the ~mbedded connaction
section 22, whereas in the embodiment according to
Figure 6, a ring section 36 is disposed between
the connection section 22 and the retaining
section 24, which ring section is substantially
the same thickness as the disc body 2 and directly
surrounds the outer periphery 12 of the disc body
2.
In tne embodiments according to Figures 5
and 7 the retaining section 24 of the segment
carrier ring 14 immediately following the embedded
connection section 22 is substantially the same
thickness as the disc ~ody 2. Thus the segment
carrier ring 14 in this case is approximately T-
shaped in cross-section. The surface of the
retaining section 24 facing radially outwards
forms a securing surface 38 curved in a convex and
arcuate manner, the cutting segment retaining
devices 30 being retained, in particular stuc~, on
this securing surface 38 of the segment carrier
ring 14 by means of securing surfaces 40 curved in ~-
a correspondingly concave manner. Ih the
embodiment according to Figure 7, the cutting
.
segment holding devices 30 in addition comprise in ~ ~ ;
sach case a dove-tailed recess 42 for holding the
cutting segments (not illustrated) In an inter-
locking manner. As an alternative to the latter,
1 8
the cutting segments are conventionally soldered
onto the cutting segment retaining devices 30
before the latter are connected to the segment
carrier ring 14.
In accordance with Figure 8 the segment ~?~
carrier ring 14 is divided into a plurality of
individual arcuate ring sections 43 which are, or
can be, connected to one another in particular by
means of interlocking connections 45. Preferably
, . ,
the;interlocking connections 45 are in each case
in the rorm of a dove-tail connection. This
embodiment of the se~ment carrier ring 14 is
particularly suitable or stock blades having a
very large diameter. In order that the segment
carrier ring 14 and the 1ndividual ring sections
43 thereof can be correctly aligned and positioned
during manufacture o the stock blade according to
~ ,
the invention, the segment carrier ring 14 i~s
connected, or can be connected, via a plurality of
spoke-like connector slements 46 which are
distributed over the periphery and are-to be
d1sposed in the plane of the central layer, to a
cen~ral sscuring body 47, interlocking connectlons
45 ~lso being provided for these connections
between ths conneotor elements 4~ and the ring ~ -~
sections 43 on the one hand and the securing body ~ `
47 on the other hand. Figure 8 illustrates by ;~
- ` 2 ~ 7 2 ~
1 9
means of arrows 48 the process for assembling the
said individual parts of the segment carrier ring
14 which should thus be readily comprehensible. As
can further be seen in Figure 8, each ring section
43 comprises a plurality of ring members 49 which
are connected to one another in an integral mann~r
in the outer peripheral area of the segment
carrier ring 14 by means of narrow connection bars
~1 This means that the ring members 49 are
separated as far as the connection bars 51 by
means of radial slots or intermediate spaces 53,
this segment carrier ring 14ibeing connected to
the disc body 2 in such a way that the connection
~ars ~l are disposed completely externally of thé
disc body 2, i.e. at a radial spacing from the
outer periphery 12 (shown in broken lines in
Figure 8), so that openings 54 are formed between
the outer periphery 12 and the connection bars 51.
The~purpose of this arrangement will be explained
in further detail below.
In a further development of the invention
llustrated in Figures 9 to 14 and also in Figure
20 the disc body 2 comprises ducts 44 (only
;,
illustrated by broken lines in Figures 9, 10 and
20) passing thr~ough the area of the central plane
thereo~. These ducts 44 extend substantially
radially from the inner area to the outer ~ -
2 ~ 5
periphery 12, namely in particular through the
central layer 20 and optianally also through the
segment carrier ring 14. The ducts 44 can serve
two different purposes. On the one hand, there cAn
he supplied via a clamping device a coolant which
then flows via the ducts 44 to the outer
:,
peripheral area and emerges between the cutting
-
segments in order to cool the latter during
machining. On the other hand, the ducts 44 can
also be closed at each end and thus be filled with
,
a sound-dampiny medium. This posqibility serves to ~-
aamp noise and vibrations ef~fectively. `;
At this point, reference is-again made to
Figure 8 which illustra~es by means of one of the
ducts 44 (shown in broken lines) that the latter -;~
passes through the area of a slot or intermediate
space 52 formed between the ring members 49 of the
segment carrier ring 14 and opens out outw rdly on `~
the outer periphery 12 of the disc body 2 in the -
area of the opening 54 formed between the outer -`
periphery 12 and the respective connection bar 51.
As a result thereof, a coolant, delivered from the
central area, can be discharged via the opening
,
~; 54.
In accordance with Figures 9 and 10, -
radial s~gment slots 55 can be formed on the outer
~ i 2~9~72~
periphery of the di~c body 2, the ducts 44 then
opening out outwardly in the base area of these
segmerlt slots 55. Figure 10 shows that the disc
Dody 2 is formed integrally with the flange 10,
the ducts 44 extending through the 1ange 10 at
least as far as a supply opening 56 into which a
coolànt can be supplied via a suitable alamping
device 57, as explained below.
. ,":,,
Figures 11 to 14 illustrate some examples
o~ the clamping devlce 57. In Figures 11 and 12
- cne stock blade 2 is formed lntegrally with the
flange lO in each case. The ducts 44 open out `
radially outwards in the vicinity of the flange 10 ~ ~
via the supply opening or openings 56 so that a ,~ A,.`"',,,
coolant can be supplied in the radial direction
"
l ~arrow 59) via a stationary, i.e. non-rotating,
part 58 of the clamping device 57. Thus a seal is
,:
provided in a manner known per se between the
rotating and non-rotating parts. The two ~ ;
embodiments in Figures 11 and 12 only differ with ~ -
respect to the type of a holding part 60 provided
or clamping the stock blade, the holding part 60
accord~lng to Figure 11 being disc-shaped and ~~
engaging in an accommodating recess in the stock
` Dlade. In contrast,~the holding part 60 in'the
embodiment according to Figure 12 lies outwardly ~- -
on the stock blade surface. In both cases the
;~ ' ' , ,~, , ':' .'.
!; 2~.9~72~
nolding part 60 is connected to a drive shaft 62
~y means of a screw connection. In the embodiment
according to Figure 13 the flange 10 is in the
form of a separate part connected to the disc body
2 via screw connection~. In other respects this
arrangement corresponds to the one in Figure 12.
In the arrangemant according to Figure 14, the
! :
disc body 2 doe~ not h~ve a flange. The ducts 44
terminate in the radial direction internally in ~ -
the vicinity of the assembly opening 8 and here
form radially inwardly directed supply openings :., .
: 56. This disc body 2 is mounted on a shaft ~:
,
attachment of the drive shaft 62 ant is clamped ~ ,~
wlth the holding part 60. The shaft attachment
: , .
thus has a peripheral annular recess into which
both the supply openings 56 and an axial duct 64
o the drive shaft 62 open. '~
In an advantageous further development of ~ .
the invention not illustrated in the drawings the . : -
disc body 2 comprises on both the surfaces thereof
in each cas~ one wear-protecting coating, which
advantageously protects the fibres in the vicinity
of the surIaces from mechanical influences ~ :
fricti.on). The stock blade according to the ..
lnVentiOn thus has a particularly long useful
life.
11 20~7~
Wlth relerence to Figures 15 to 20 the
methoG and apparatus used to produce the stock
blade l according to the invention will now be
~r~L iy sxplained.
,
igures l5 to l9 in each case show the
c bo~y ln b~oken lines. This shape lS
produced from t~e piaslics material 6 by means of
:
ng or ~r,je~cion moulding tool, the fibres `
havlng ~eell iepO91~ ed previously. For this
pus~o~e Ll~e manuiacturlng apparatus according to -
the inv~ntlon has a plurality of outer securing
plllS 50 or similar securing elements distributed
over the outer periphery of the tool and
op~ionally also in the central area at least one~
inner securing pin 52 (Figure 18) or a plurality - ;~
,
of lnner securing plns 52 (Figure 19) distributed
over the periphery. In order for the fibres 4 to ;
~e ~ ts~uted over the periphery as uniformly and ;~
compactly as pO3Si ble, i.e. covering the surface,
a5 many ~tel ~ee ur~ng pins 50 as possi L~l e should
0~ provlded WillC;l - as illustraled - can iie on a ;~`
, iU~ al. ~f ~Ji t ;:~' example twoi concentr~c circles
~ ~ ,
dnd dre~thus il3possd offset reiative to one
c.~her ln tne peripheral direction in each case.
Ln the emDodiments illustrated, the outer securing
pln~ J0 ~I e disposed externally of the subsequent
three-dlmerlilonal snape of the disc body 2.
2 ~ 7 2 ~
24
Alternatively, however, it is also possible for
e outer securing pins 50 to be disposed
precisely within, i.e. adjacent, thé outer
per~phery 12 so that the securLng pins 50 are then
emhedded with the fibres 4 in the plastics
ma~e~ial 6. ~he indivldual inner securing pin 52
according to cigure 18 is advantageously precisely
centre of the disc body 2, i.e. ln the
iCillity o~ the assembly opening 8 such that this
~ecurllly ~ lS not also embedded. The
plural i ty of inner securing pins 52 according to
:, .
yure i3 are in the vicinity of the flange 10
such that they are also embedded in the plastics
ma~erial 6. For this purpose it would
alternatively also be possible for the securing
~ins 52 to be disposed in the vicinity of the ~-
.) assembly opening 8 such that they are then not
embedded.
, ` ' .~ '
In accordance with the invention the
Libres ~ aLe Iirstly deposited such that they are
o~iented a~ 1east approximately radi ally and ;~
L.~ i Lr~ a layer-like manner and uniformly ;~
over ~ per~p~ery~ias a result o} being wound
~ . ,
b~,u~ ~h =ecuring pins 50 and optionally 52.
There are number of possibillties for the above,
of which only some are indicated in Figures 15 to
~;~ 19 by way of example, although the invention is
, .: .
.''`'".' ' ,"'',', '.`',' ''`'".,. '.'" ' "'~," '~' ;,~,
`~ 2~7~
not restllcted to these examples. With all the
possibillties it is advantageous to use csntinuous
fibr2s which are available wound in the form of
_~L'~, in oraer to àeposit the fibres 4.
,
In dccordance with Figure 15, starting ~ ;
roln ~ny outar securing pin 50, the continuous
) fibr_3 ar_ guldad to the diametrically opposite
~_r ~_curing pin 50. The fibres are wrapped
around ~hlg pin and are then guided to the pin
Jd'_L~ e diametrically opposite pin and so on.
Tne winding process can be performed very easily,
d3 sllown by che arrows in ~igure 15, from which it
can be 3een tha~ the fibres are always wrapped
arourld ;he outer securing pins 50 in the same
directlon.
) ' ' ~ .,
In contrast the winding technique `
il'ldlCataQ in Figure i6 only difIers from that
accorQing to Figure 15 in that the fibres are in `
ed_h Cd-i wIapped around the respactive securing `~
pin~ ~0 QlallletrlCa1 iy opposite one another in
_~LL~ lL~ec~ions which mean~ that here the -~;
Llb~eg dLC wrdpped around the pins in a figure-
`~L-il9nt drrangem-nt in each case. The wrapp~ng of
the ~ibreq can also be achieved very easily in
tllis cd~e according to the arrows shown. ~
209V725
26
;n rlguLe ,~ the fibres 4 are likewise
~ul -~ Erom any outer securing pin 50 to the
diameirically opposite securing pin, but from the
i~tt~l ~o ~:~e securlng pin immediately adjacent
ther~to and from here to the diametrically
~p~e3~3 ~n ~hereof and so on. Thus, as in Figure
15, the fibres can always wrap around the pins in
thc sam, ~irection or, as in Figure 16, in a ~ ~;
figure-of-eight in each case, with the fibres ;~ ;
, - . .,:
~jin.~ wra~ped around the pins in difEerent -;
irectlon~
'n the casr3 of the winding technique
- L~ LCL~-~ in r~gurt 18 the ~ibres are always ~;
;, ' , :' ~ ' !, . .
~oun~ ~"hwa~ ds ~LSIa orwards between the outer
~_CUl Ln~ plnS 50 and the individual inner securing
i
pin 52, on the exterior the fibres passing in
step~ Lrom one securing pin 50 to the other. The
fi~res can be wrapped in the same direction, as i~ -
qnown ln rigure 18, or in dif~erent directicns in
a figure-oL-eight in each case. . ;~
cigu~e ;9 illustrates a winding technique
31n~ tnr3 ou~er securing pins 50 and a plurality
vL Lil~lC~ ~eour lng ~ins 52. In this case the number
o~ lnllr3r secullng ~lnS 52 of necessity is smaller
~;.qn !'.l- n~n~.3r oE outer securlng pins 50. For
I eason a plurality of outer securing pins
r~
27
disposed in a circular sector are associated with
each inner securing pin 52 in each case. The path
of the fibres 4 can be readily seen in Figure 19,
In all the winding techniques a plurality
of layers ar~ pre~erably wound one above the
other. In this connection it is essential for the
fibres to be deposited with constant tensile ' ,
stress in order to impart to the stock blade the '~
"radially isotropic" properties thereof. As can be
seen from Figure 20~in particular the first fibre
layer 16 (comprising a plurality of wound layers)
is deposited first of all. Subsequently the ' ~ "'~ ~
central' layer 20 i5 applied to this first fibre '~- ,.
layer 16 in particular in the form of a ;~ ,;,
~refabricated filling member, namely if necessary ' ,~'
,) ,-
together with the segment carrier ring 14. The
second fibre layer 18 is then laid on the central , '~
layer 20 in a manner similar to the first layer
16. This second layer is not illustrated in Figure
20, i.e. it cannot yet have been deposited in the
:~
stage of the method illustrated. Finally all the
layers are jointly surrounded with the plastics
~a~erial by means of the shaping tool, i.e. the'y
are embedded in the plastics material such that a '`~`"r
. .;~ , ~ :
-! materially-uniform composite as regards material ~,~
is produced. The cross-sectional contours of the
` ~inished disc body 2 are shown in broken lines in
209~72S
28
F~gure 20. It is essential in this connection for
rne s~curlng oi- the fibres 4 by means of the
SeCUrlng pins 50 and optionally 52 to be
maintalnad even when the plasti~s material is
hardiening in order to ensure that the fibres 4 are
still su~ject to the tensile stress imparted
thereto during the winding process after the
piastics materiai has hardened. When the plastics
material has hardened, the blank is removed from !:
.
~he mOlG anà subsequently machining is performed
in that the projecting fibres 4 in the outer -~
perlphcrai area are cut off.~The assembly opening
3 is pr~duced in ti~i~e central area. In the event of
~.i_ ecurlny pinc ~0 also belng embedded in the
oute~- perlpheral area, it is advantageous for the
dlSC body 2 firstly to be produced such that it is
oversized - relative to the diameter - and then
~, for tne area containing the pins 50 to be machined
away. The individual, central securing pin
according to Figure 11 is likewise removed when
the assembly opening 8 is produced. The plurality
of internal securing pins 50 according to Figure
12 could relnain in the vicinity of the integral
: , ,,; ~:~,
L~ JC ~ n .
As an alternative to the method described
eL~0, 1~ lS also possible to form the central ;~
layer 20 slrnultanFously with the moulding process,
2 ~ 7,~ ~
i.e. at the same tlme as the plastics material is
in~ction moulded or cast therefrom. For this
purpose, when the first ibre layer 16 has been
~eposlted, suitable spacers and then the second
fibre layer 18 are disposed thereon. During the
moulding process, the plastics material then also
penetrates between the fibre layers 16, 18 to ~orm
the oentral layer 20. The spacers can remain in
tha central layer 20 or be removed by melting, for
-~ample. ~n this connection, before the moulding
process, filling mem~ers corresponding to the ~ -
~i~dpe CL the abo~Jsmentioned ducts 44 could also be ,;
~sert~d in order to form the said ducts, these
r iillng m~ bers then being removed from the
-entral layer after the moulding process in ordèr
to ~orm the ducts. For this purpose it is possible
to ùse for the filling members a material which
melts under the effect of heat, the filling
members being melted for removal. ~lternatively,
the filling members can consist of-a wire material
or e~ample, and be surrounded with a separating
dgent beEore insertion, as a result of which a
material conne~tlon with the plastics material is
dVOldbd. ~he Eilling members can then be removed
~rom tne p;astics material in a simple manner, as
bX~it 01 whlch tne ducts 44 are formed. ;~
.'
a
2 ~3 9 ~ 7 2 3
'; , ' ~
,',~,
It is i,urthermore particùlarly ,
advancageous Lf subsequently a surface wear-
rotectillg coa~ing i9 applied in a suitable manner
0 t_rle SCO_f. ~laae, alter moulding. This coating
~an be sprayed on, for example. ,
~ ' ,
In an advantageous ~urther development of
the inv0ntion (not illustrated), i.e. of the , ~,
pro,duction apparatus according to the invention, ,,~
tAe ~latt2r has-a depositing device which is
p'articular program-control,led for automatically
winding the continuous-fibre~,material about the
securlng plns. This depositing device has a
movable depositing head of which the movements can
De programmed according to the winding plan in
-acn case.
The invention is'not restricted to the
embocilmen~s de~cribed and illustrated but also
sncompasses all similar arrangements within th9 ~ -
spirit oi, the invention. ~ ~ ~
: ~: ,. -
