Note: Descriptions are shown in the official language in which they were submitted.
~3243~;
This application is a division of Canadian Patent
Application No. 430,871, filed June 21, 1983.
This invention relates to manufacture of hollow, fife-
Monterey composite tubes that can be used, for sample to
transmit torque in the drive train of motor vehicles. Fife-
Monterey composite tubes have been proposed for reduced wright
shafts in thy drive train of motor vehicles. See, for exam-
pie, US. Patents 4,171,626; 4,236,3~6; 4,238,539; 4,23&,540
and 4,289,557. See, also, "Development of an Advanced Come
posit Tail Rotor Drive shaft" by in berg it at presented at
thy Thea Annual National Forum of the American Helicopter
lo Society, Washington, DO June 1970.
Fabrication of composite tubes by applying fiber to a
cylindrical mandrel is known. Sue, for example, US. Patents
4,248,062; 4,532,579 and 3,407,101. This invention differs
from these prior art techniques in that it provides for sue-
cessive production of suitably reinforced composite tubes using a continuous tubular mandrel of joined mandrel segments.
US. Patents: 2,714,414 (Gunwale et at.); 3,723,705
(Collins); 4,125,423 (Golds worthy); 4,309,8~5 (Brunch et
at.) disclose tub making processes in which a segmented man-
duel body is in relative motion with respect to composite tube forming devices operatively engaging such segmented man-
duel body. The present invention is characterized by in pro-
cuss aspect as passing a tube-shaped, segmented mandrel come
prosing endues joined segments lengthwise through a series
of tube fabricatirlg devices for (i) forming a resin and fiber
tube comprising continuous filamentary reinforcements about
said segmented mandrel passing there through (ii) hardening
said resin and fiber tub around said segmented mandrel after
said forming; and (iii) severing adjacent the juncture be-
tweet adi~c~ntly joined s~gmerlts of said segmented mandrPlthe tubular product of said rosin and fiber tube that has
hardened sufficiently for said severing; as this passage
~23~435
--2--
through said series continues, disconnecting from segmented
mandrel the leading segment thereof that carries a composite
tube that has been severed from said tubular product in
conjunction with connecting a fresh mandrel segment to the
other end of said segmented mandrel as a replacement for such
disconnected leading segment; separating the composite tubes
from said mandrel segments that are disconnected from said
segmented mandrel to provide said hollow composite tube
members.
The above cited patents also disclose machines for
implementing each of the disclosed methods. The machine of the
present invention is characterized by: support for passing a
segmented mandrel lengthwise through a plurality of
longitudinally spaced tube fabricating devices; longitudinally
spaced filament applicators for applying diversely angled
continuous filamentary plies to said segmented mandrel atop
each other; a reciprocating wrench for periodically joining
segments to an end of said segmented mandrel that is upstream
from said tube fabricating devices; a reciprocating wrench for
periodically disconnecting joined segments from an end of said
segmented mandrel that is downstream from said tube fabricating
stations; a saw for severing a composite tube
circumferential, said saw located between the other tube
fabricating devices and said downstream wrench.
In one broad aspect, the present invention relates, in
a machine for producing filament wound composite tubular members
using a segmented mandrel body, to the improvement which
~L2~2435
comprises a segmented mandrel having mandrel segments joined
together along a common central, longitudinal axis, each of
said mandrel segments comprising: a hollow tube dimensioned
suitably for each of said composite tubular members; first and
second mounts secured within said tube and respectively
carrying a threaded socket and a threaded plug that, in turn,
thread respectively with any of the other threaded plugs and
sockets carried by the other mandrel segments of said segmented
mandrel, said threaded plug and threaded socket each being of
lesser diameter than said tube and having center longitudinal
socket and plug axes coincident with that of said segmented
mandrel; said threaded socket having an unthreaded socket
portion of somewhat less diameter than the threaded socket
portion thereof, said unthreaded socket portion extending along
said socket axis from such threaded socket portion inward
towards a center position of said mandrel segment between said
threaded socket and threaded plug, said threaded plug having an
unthreaded plug portion extending along said plug axis away
from the threaded portion thereof and from said center
position, said unthreaded plug portion comprising a diameter
somewhat less than that of each of the unthreaded socket
portions of said other mandrel segments for sliding engagement
therewith during threading and unthreading engagements thereof.
Also disclosed are: a method of manufacturing a hollow
composite tube, the subject matter of parent Canadian Patent
Application No. 430,871 which matured to patent on October 14,
1986, as Canadian Patent No. 1,212,529; a hollow composite tube
suited for transmitting torque as part of the drive train
I ~232435
thereof, the subject matter of Canadian Patent Application No.
514,910 a division of Canadian Patent Application No. 430,871,
filed contemporaneously with the present application and a
machine that manufactures composite tubes, the subject matter
of Canadian Patent Application No. 514,909, a division of
Canadian Patent Application No. 430,871, filed
contemporaneously with the present application.
In the following description of this invention:
"Process mandrel" means a continuous tubular mandrel formed of
discrete mandrel segments joined to each other along their
central longitudinal axes and around which a tubular composite
can be formed. "Mandrel segment" means a tubular segment that
can be connected to and disconnected from the process mandrel.
"Composite tubular member for a light truck" means a fiber and
resin tubular body having continuous filaments in thermoses
resin, the structural properties of which tubular body are
exemplified by critical frequency not to exceed 98.23 Ho, shear
torque 56,000 in-lb, buckling torque 56,000 in-lb. "Process
mandrel portion" means a longitudinal portion of the process
mandrel which includes any number or portion of its joined
segments. "Layer" means a pair of filamentary plies, a first of
which is disposed at a plus or minus first angle relative to a
line parallel to an axis and the second of ~lhich is disposed at
a second angle of about the same magnitude as the first angle
but the negative ---
1;~3Z43~;
thereof relative to such line. ply moans a group of fife-
mints disposed at the substantially same angle in a geometric
plane concentric with a mandrel portion which plane is nor-
molly cylindrical or substantially cylindrical in this
invention.
Figure 1 outlines diagrammatically a process sequence
that utilizes this invention in producing composite tubes
thereof.
Figure 2 schematically depicts a cross section of end
lo portions of two joined mandrel segments used in practicing
this invention. The end portions are depicted with the come
posit tubes they carry after the cutting operation in the
sequence of Figure 1.
Figure 3 schematically depicts in perspective an apply-
actor for applying helically disposed fibers to a process mandrel portion passing through the applicator.
Figure PA is a detail of the annular deposition ring as-
symbol of a wheel depicted in Figure 3.
Figure 4 schematically depicts in perspective an apply-
actor for applying longitudinally disposed fibers to a pro-
cuss mandrel portion passing through the applicator down-
stream from the portion of Figure 3.
Figure PA is a detail of fiber application ring of an
applicator in Figure 4.
Figure 5 schematically depicts in perspective an apply-
actor for applying circumferential disposed fibers to a
process mandrel portion passing through the applicator down-
stream from the portion of Figure 4 or Figure 3.
Figure 6 schematically depicts a cross section of a
rosin applicator chamber for impregnating fiber carried by a
process mandrel portion passing through the chamber down-
stream from thy portion of Figure 5.
Figure 7 schematically depicts in perspective a bank of
induction coils used to cure a resin and fiber tube carried
by a process mandrel portion passing through the coils down-
sternly from the portion of Figure 6.
Figure 8 schematically depicts in perspective a two
blade rotating cutting wheel for cutting a moving tube of
123Z435
-- 6 --
hardened rosin and fiber produced in accordance with this in-
mention and carried by a process mandrel portion downstream
from the portion of Figure 7.
Figure 9 schematically depicts in perspective an into-
grated device that disconnects mandrel segments and subset
quaintly draws a composite tube from each of the disconnected
mandrel segments. Thy mandrel segment being disconnected is
. downstream of the process mandrel portion of Figure 8.
- figure lo is a view of a drive shaft member of this in-
mention in elevation, including end fittings
Figure lo is a diagrammatic depiction of a wall portion
of the composite of Figure 10.
Figure 1 shows thy fabrication steps which result in
composite drive shaft tubes for light trucks in accordance
with this invention. The fabrication sequence is illustrated
in Figure 1 as a series of steps set forth in the order in
which the tubes are made.
In general, endues joined segments of a process mandrel
sequentially proceed lengthwise through the tube fabricating
stations identified in the fabrication sequence of Figure 1.
In the final tube forming operatiorl, however, individual man-
duel segment of the process mandrel are disconnected and a
completed composite tube is extracted from each disconnected
segment, the latter occurring off line from steps that pro-
cede it. Also, in the beginning of this process sequence afresh mandrel segmerlt is periodically joined to the rear man-
duel segment of the process mandrel. The fresh mandrel sex-
merit being joined to the process mandrel may have a cylinder-
eel metal sleeve around either or both of its ends whereby
the metal sleeve becomes integrated into the composite tube
produced my the sequence of Figure 1.
At the beginning of the tube fabricating process so-
quince depicted in Figure 1, a mandrel segment, as mentioned,
is joined to the rear of a previously assembled process man-
duel at joining station A. The process mandrel comprises number of connected segments which together have a common
central longitudinal axis. (Sue Figure 2 for a cross-section
of two joined mandrel segments). Hand over hand clamps at
AYE
station R continually pull thy process mandrel away from
joining station A and through the other tube fabricating
stations that aye downstream thereof.
A moving grip jaw at station A prevents rotation of the
moving process mandrel. Thy grip law holds the process man-
duel while the unconnected, fresh mandrel segment is spun
into locking engagement with, and becomes the rear segment
of, the process mandrel proceeding as a train of seglllents
through downstream tube fabricating operations. An upstream
ball rail mounted wrench rotates in spinning this unconnected
mandrel segment into the locking relation at station A. The
rotating wrench translates in a downstreani direction long-
tudinally along the upstream extension of the process mandrel
central longitudinal axis in joining the new mandrel segment
to the process mandrel. A bed of rollers carry the end of
the process mandrel and the mandrel segment being joined
thereto during the joining operation. The rollers are rotate
able in the direction that the process mandrel proceeds.
At station B dry fiber is deposited around the portion
of the process mandrel that proceeds there through. Station B
comprises a helical applicator. The helical applicator de-
posits a ply or plies of continuous filaments either at an
angle between about +35 and +55 or between about -35 and
-55 relative to a line parallel to the central longitudinal
axis of the process mandrel. There are four helical applique-
ions in the fabrication sequence of Figure 1, labeled B, D, F
and I each of which applicators deposits a ply or pair of
plies at an angle within the above ranges.
Helical applicators of station B, D, F and H each come
prose a wheel having a plurality of fiber carrying spools spaced about its periphery. The wheels of adjacent stations
rotate at similar rates (but opposite each other) in spinning
the continuous filaments about the process mandrel from these
spools (see Figure 3 for a view of the two counter rotating
wheels). As a result of passage of the process mandrel
through fiber deposition at these wheels, segments of the
process mandrel are keyword with a layer or layers of con-
tenuous filaments, as desired. For example, two layers of
1;23Z43S
-- 8
continuous filament can be deposited by stations B, D, F and
H. Unmaking light truck drive shaft tubes, each pair of the
stations deposits a layer of filament Top layer has a +45
ply and a -45~ ply where these angles are each relative to a
line parallel to the central longitudinal of the process
mandrel.
In making these truck drive shaft tubes, each of stay
lions B, D, F and H deposits between about .024 and .334 lobs
of fiber per linear foot of the process mandrel. Each of
these station B, D, F and H can utilize up to 80 rovings with
yields of 113 and 1800 yards. per lb. where the rovings each
comprise E-glass filaments.
Stations C, E, G, I, K, M and O in the sequence of Fig-
use 1 provide for impregnation of the fiber deposited on the
process mandrel. Station C like the other of these stations
(except station O) includes a resin impregnation chamber lo
cross-section of a typical resin impregnation chamber appears
in Figure 6.)
Station O utilizes a tubular conduit communicating with,
and suspended from, a resin supply tank for direct applique-
lion of resin. the resin passes through the conduit and onto
the sassing fiber and resin tube proceeding from station N.
The resin is worked into the passing fiber at station O by a
downstream roller such as a paint roller that continuously
circles the segmented mandrel. A rotating elastomers wiper
blade downstream of this roller wipes resin from the fiber.
Impregnation alternatively, however, can occur by means
of impregnation chamber or such direct application at any or
all of stations C, E, G, I, K, M and O. For example, station
M could be omitted.
The process mandrel proceeds through the impregnation
chamber of stations C, E, G, I, K, M and O (and the other
stations) at any desired rate preferably between 1.5 and 6
feet per minute in the sequence being described. At these
rates, the fiber absorbs about an equal volume of thermoses-
table resin. Fiber wetting reaches an equilibrium at about
50 percent of the total composite volume Additional impreg-
nation stations do not significantly affect the fiber to
resin ratio.
9 12~2435
Station J in the sequence of Figure 1 deposits dry fiber
around the process mandrel over the impregnated fibers there-
of as it proceeds from the impregljation at station I. Stay
lion J comprises a rotating hoop applicator wheel that no-
tales to wind a band of continuous fiber as it spins around the moving process mandrel. (See Figure 5 for a view of this
wheel). The hoop applicator applies a ply of continuous lit-
amens to the moving process mandrel at an angle between
about either +80 or -80 and 90 relative to a line parallel
lo to the central longitudinal axis of the process mandrel.
For a truck drive shaft tube made using a process man-
duel having a four inch diameter and proceeding at a rate
described, the hoop applicator spins around the process man-
duel at between about lo and 72 rum in depositing a 1 inch
wide band of E-glass filaments that contains of between ll3
and 1800 yards. per lb.
Station L deposits continuous graphite filaments about
the fiber wound and resin impregnated process mandrel pro-
ceding from stations J and K respectively. Station L depose
its continuous filaments about the process mandrel at annoyingly of about 0 relative to a line parallel to the long-
tudinal axis of the process mandrel. Station L preferably
utilizes two or lore longitudinally spaced distribution
rings. rovings pass through these rings and then lay upon
the previously fiber covered and resin impregnated process
mandrel as it travels through the rings. (See Figure 4 for a
view of the longitudinally spaced applicators of station L).
The rings each comprise an orifice which encircles the
process mandrel; the rings each have holes spaced around
their peripheries. The holes guide the rovings as thy lay
upon the fixer covered and resin impregnated process mandrel
proceeding through the rings from station K or from an up-
stream ring of station L. Holes of the adjacent distribution
rings are offset from each other so that the yarns or rovings
are lazed all around the fiber covered and resin impregnated,
process nlandr~
~3~35
-- 10 --
The yarns or rovings at station L have between about
1200U and 36000 filaments per roving in making the truck
drive shaft composite tubes. the yarn or roving in making
these drive shaft tubes comprise graphite filaments that are
S A-graphite. Together these filaments weigh between about
Oily and 0.328 lobs per linear foot of the process mandrel
after exit from station, L. The rovings issue from the disk
tribution rings at up to about six feet per minute in making
such tubes.
Station (of the sequence of Figure 1) wraps the long-
tudinally disposed filaments carried on the process mandrel
front statiOrl L with a hoop ply of dry filamellts. The hoop
ply is deposited by rotating hoop wheel applicator such as
discussed in reference to station J Stations J and N each
deposit the hoop ply of dry fiber at plus and minus angles of
either between about +80 and 90 or between about -~0 and
90 relative to a line parallel to the center longitudinal
axis of the process mandrel in making the truck drive shaft
composite tubes.
Station O applies liquid thermosetting resin to the it-
bier and resin covered process mandrel proceeding from station
to, as described above.
The fiber and resin covered process mandrel, impregnated
at station o thin prods therefrom to station P which in-
shuts cur of the thermosettabie resin, station P being
shown in the sequence of Figure 1.
A plurality of induction coils initiate this cure at
station P. (The device carrying these induction coils is de-
plated schematically in Figure 7). The induction coils pro-
vise a sufficient temperature increase in the rosin to result ultimately in a cure thereof. Generally, in making the truck
drive shaft tubes, the temperature of a mandrel segment
leaving station P desirably will be between about 250F and
325F, when using vinyl ester thermosetta~le resin such as
Darken from Dow Chemical Corp.
Station I Of the sequence depicted in Figure I comprises
infrared hotels. The heaters increase the outside skin
temperature to 200F. A bank of five infrared heaters are
I`
~X3;~:435
-- 11
mounted around a 6 foot long cylinder. Station Q ~llminat~s
surface tack which may exist when curing thermosettable resin
containing a Sterno monomer in air.
Some distance exists between station Q and station R.
Station R of top sequence depicted in Figure 1 grips the
hardened resin tube proceedirlg from station Q. Station R
grips the composite tube sufficiently to pull it through the
proceeding stations. Station R has two hand over hand grip-
ping clamps. The hand over hand gripping mechanism may be
purchased from Golds worthy Engr. of Torrance, Cal.
Station S of the process swoons depicted in Figure 1
Severs the hardened tube proceeding from station R. Station
S comprises a pair of rotating saw blades. The saw blades
cut the curing or cured tube around either side of the junk
lure between two joined mandrel segments of the process man-
duel. The blades rotate about top process mandrel to sever a
composite tube completely from the upstream portion thereof.
(See Figure 8 for a view of the cutter. The short cylinder-
eel section of composite tube formed between the blades by
top cutting action thereof is removed at station U during the
pulling of the mandrel segments from their respective compost
tie tubes.) The blades translate along a line parallel to
the central longitudinal axis of the process mandrel in so-
vexing the cured tub as it proceeds through station S.
After the tub is severed the blades together translate
upstream to their starting position.
Station T of the process sequence identified in Figure 1
disconnects top mandrel segment carrying a severed tube from
the rest of the process mandrel. A clamping jaw at station T
prevents rotation of the process mandrel by gripping an up-
stream portion thereof around the cured composite tube that
it carries. The downstream joined mandrel segment is then
disconnected from the rest of thy process mandrel by a rotate
in hex wrench at station T. The rotating hex wrench engages
the leading mandrel segment (carrying the composite tube so-
veered at station I) and spins it free of the moving upstream
train of joined mandrel s~gmPnts. (See Figure 9 for schema-
tic view of the mandrel segment disconnecting and tube
extracting device combination.)
1~32435
The disconnected mandrel segment carrying the cured come
posit tune proceeds to station U of the process sequence de-
plated in Figure 1. Station U is at the side of the main
machine axis. The composite tube is extracted from the disk
connected mandrel segment in an extraction die. The disco-
netted mandrel segment is pulled through the extraction die
stropping the cured composite tube. The disconnected mandrel
segnlent proceeding from the extraction die, now free of the
cured composite tube, then proceeds to station V which con-
lo twins a mold release bath. The freed mandrel segment instill at elevated temperature (e.g. 130F.) as it enters this
mold release bath. The elevated temperature helps bake the
mold release of thy extracted mandrel segment.
The cured composite tubular member, when freed of the
disconnected mandrel segment, can be rolled to a storage
cart. The mandrel segment, when freed of the cured composite
tubular member can be returned to station A for further use.
he composite tubular member when used in a truck drive
shaft can incorporate a metal sleeve at each end. The metal
sleeve can be adhesively bonded within, or on the outside of,
the tube. Alternately each mandrel segment can carry metal
sleeves at its ends through the fabrication sequence of Fig-
use 1. These sleeves act as parts of the mandrel segment in
that the composite tube is formed about them. A riveting opt
oration can rivet the sleeves in this latter case to the come
posit tubular member after completion of tube manufacture
(i.e. after station V).
The method of this invention has been described in a
tube fabrication sequence suited for making truck drive shaft
composite tubes. AS, however, may be apparent, such sequence
is but illustrative of the many sequences that can be used in
making these or other composite tubular members using prince-
pies of this invention. Another sequence is A, B, C, D, E,
J, K, L, M, I, P, Q, R, S, T, and V; different combinations
of fiber yield and numbers of rovings can also be employed in
any of these sequences.
Figures 2 through 9 lust rate equipment identified in
previous description of the process sequence of Figure 1.
13 _ ~3Z435
Figure 2 s a cross-section of the joined ends of two
cylindrical mandrel segments 10, 12 that are used in making
composite drive shaft tubes for certain light trucks in con-
section with thy process sequence of Figure 1. Joined man-
duel segments 10, lo have cylindrical steel sleeves 14, wish slip over their respective ends. Plastic sleeve 13
fits cylindrically about and between adjoining end portions
of steel sleeps 14, 16 and between segments 10, 12.
The opposite Ponds (not shown) of each mandrel segments
10, 12 are configured to permit their respective joining with
other mandrel segments
Mandrel segment male member 20 is bolted to mandrel sex-
mint 12 and has integral map amp threads 22 for connecting
mandrel segril~nt 12 to mandrel sPgmPnt lo Mandrel segment 10
lo has socket 24 with threads 26 for receipt of threads 22 in
locking relation. mandrel segment 10 joins to mandrel sex-
mint 12 with relative rotation between them of betwPPn about
I and 2 revolutions. The unthreaded portion of male member
20 guides the approach and retreat of mandrel segment 12 to
and from mandrel segment 12.
Mandrel segments lo 12 depicted in Figure 2 have pro-
cPPded through tube cutting station S in the sequence of Fig-
use 1. circumferential spaces 28, 30 depict where station S
has severed the composite tube carried by the mandrel sex-
mints 10, 12. Mandrel segment lo leads mandrel segment lo in this sequence in the direction shown in Figure 2. Accord-
tingly, mandrel segments 10, 12 carry downstream cured compost
tie tube 32, upstream composite tube 34 and intermediate come
posit tube 36. Downstream composite tub 32 becomes, with
sleeve 16 and a sleeve (not shown) at top other Pond of man-
duel segment 12, a drive shaft member of this invention after
it is separated from mandrel segment 12~ Upstream composite
tube 34 becomes another drive shaft member with sleeve 14
(and other sleeve) once tube 34 is severed and the severed
tub separated from mandrel segment lo Intermediate compost
tie tube 36 remains with mandrel segment 10 after disco-
section of mandrel segment lo therefrom until stripping of
tube 34 from mandrel segment 10 at station I.
1232435
- lo -
Intermediate composite tub 36 has been cut out at tub
cutting station S. Plastic sleeve lo serves to provide
tolerance in the depth of this cut.
Figure 3 depicts an apparatus which is depositing fiber
about process mandrel portion 38 as it passes through wheels
40, 42 carried by respective fixed mounts 44 and 46. Each of
wheels 40, 42 has a plurality of spools (a few pairs of which
are depicted as respectively, 48, 50 and 52, 54) of continue
out filament fixed around their respective faces 56, 58 and
60, 62. The wheels counter rotate, such as in the directions
shown in figure 3, in depositing continuous filaments about
process mandrel portion 38 as discussed above in connection
with stations B and D and F and H of Figure 1. Resin
impregnation chamber 64 is between wheels 40, 42.
Continuous filaments from spools 48, 50 and 52, 54 pass
to respective annular deposition ring assemblies 66, 68 which
rotate with their respective wheels 40, 42. This fiber past
sues through holes in the annular ring assemblies 66, 68 for
orientation onto process mandrel portion 38. The speed at
which wheels 40, 42 and consecluently rings assemblies 66, 68
rotate relative to the axial translation of process mandrel
portion 38 through these ring asser,lblies determines the angle
at witch top fibers deposit on process mandrel portion 38.
Figure PA is a detail of ring assembly 66 of Figure 3.
Continuous filament 70 feeds from plastic tubes such as 72
and through holes such as 74, 76 respectively in orienting
plates 78, 80. Tubes 72 serve to protect filaments 70 and
unable ready threading thereof from the spools (e.g. 48, 50)
of filaments.
Figures 4 and PA schematically illustrate longitudinal
fiber applicator 82 which is depositing continuous filaments
longitudinally (relative the center longitudinal axis of pro-
cuss mandrel portion 84) along the process mandrel. Spaced
fiber disposition rings 86, 88, 90, 92 permit issuance of
continuous fiber passing from remote spools or creels (not
shown) through their respective offset holes 94, 96, 98 and
100. Holes 94, 96, 98 and lo aye respectively spaced about
segmented mandrel portion 84 in these rings 86, 88, 90, 92.
I I
There are about 51 holes in Mach of the spaced disposition
rings 86, 88, 90, 92. Each individual hole in holes 94, 96,
98 and loo receives up to about 36000 or more filaments.
Conduits 102/ lo, 106, 108 lead from the creels to respect
live holes 94, 96, 9B and 100 to maintain alignment of thriving or yarn passing to each of these holes. The roving or
yarn issue from these holes to process mandrel portion 84
without any surrounding conduit.
In making the light truck composite tubes, there are
lo four rings longitudinally spaced between about 12 and 18 in-
ekes from each other. These rings deposit continuous fife-
mints at a zero degree angle relative to a line parallel to
the central longitudinal axis of the process mandrel.
Figure 5 schematically illustrates device 110 that is
depositing fiber circumferential about process mandrel port
lion 112. Device 110 serves the function of providing hoop
windings in the fabrication sequence of Figure 1 and
rotatable mounts to fixed mount 128.
Device 110 has wheels 114, 116 which rotate in tandem.
20 joyless 114, 116 carry spools 118, 120 about their respective
outer face peripheries 122, 124. Continuous filament feeds
from these spools to a rotating eyelet (not shown) between
wheels 114, 116 for depositing the filaments onto mandrel
portion ll2.
The eyelet rotates about process mandrel portion ll2
with wheels 114, 116 at a rate, relative axial translation of
process mandrel portion 112, which permits a desired angle of
fiber disposition.
Figure 6 is a diagrammatic cross-section of resin apt
placatory device 130 which is serving to impregnate fiber as
discussed in connection with the fabrication sequence of Fig-
use 1. Applicator device 130 comprises resin chamber 132.
Fibrous tube 134 carried by process mandrel portion 136 past
sues through resin chamber 132 which is circumferential
sealed at its mandrel entry and exit orifices by rubber ring
seals 138, 140, respectively. Resin chamber 132 is filled
continuously with resin 1~2 at inlet 144 with liquid resin at
a prosily of between about 4 ft. and 8 ft. resin head. out-
lot 146 can be used as overflow, if desired. The resin can
~23243.~
- lo
be any hard enable liquid resin and preferably is vinyl ester
thernlosettable resin (eye. Derakane*,from Dow Chemical Co.,
midland Michigan formulated with suitable peroxide catalyst
and maintained at between about 60~ and 90F. in chamber
132. The use of vinyl ester resin with peroxide catalyst
gives thermosettablP resins with appropriate pot lives (e.g.
between about 8 an lo hours) for shift operations.
Figure 7 is a schematic illustration of induction heater
device 148 which is serving the function of curing thermoses-
table resin as described in reference the tube fabricationsequencP in Figure 1. Curing device 148 is mounted on fixed
mounts 154 arid has a plurality of induction coils 150 spaced
about resin and fiber covered process mandrel portion 152
passing there through. The heating by induction coils 150 is
calibrated at various mandrel speeds to permit automatic
operation of the tube fabrication.
Figure 8 is a schematic illustration of tube cutting de-
vice 156 which is serving to sever hardened tube 158 adjacent
the juncture between joined mandrel segments of the process
mandrel as discussed in conjunction with the process
steps in Figure 1.
Cutting device 156 has rotating saw blades 164, 166
mounted to rotating disc l68. Rotating disc 168 rotates no-
toting saw blades 164, 166 about axis 170 while at the same
time translating longitudinally along this axis 170 (in the
direction shown) at the same rate as the joined mandrel sex-
mints. Saw blades 164, 166 rotate around their own axes and
this axis 170 in severing a cylindrical section (e.g. tub
36, Figure 2) from composite tube 158 on either side of the
juncture between the adjacently joined mandrel segments. The
plastic sleeve (see Figure 2) underneath the composite tube
158 provides tolerance for the cutting of blades l64, 166.
hydraulically activated clamp 160 grips composite tube
158 and prevents rotation thereof while translating with the
moving process mandrel. clamp 160 moves in tandem with
blades 164, 166 along axis 170 while they cut tube 158 and
then indexes with them back to the starting position.
* denotes trade mark
~3243~J
- 17 -
Figure 9 illustrates mandrel release and extraction de-
vice 172 which has functions as discussed in connection with
the fabrication sequence in Figure 1.
In disconnecting mandrel segments, threader, hex wrench
174 receives a hex head portion of a forward mandrel segment,
such as shown by socket end 25 of mandrel segment 10 in Fig-
use 2. inch 174 rotates while clamps in housing 176 pro-
vent rotation of the adjacent upstream mandrel segment of
process mandrel portion 178 my gripping an intermediate tube
section such as section 36 in Figure 2. Pistons carrying the
hex wrench, 174 within housing 180 translate axially in the
direction process mandrel travel during engagement of hex
wrench 174 with the end of the mandrel segment being disco-
netted. Also the clamps are piston loaded in housing 176 so
as to allow axial translation with the process mandrel port
lion 178 during this disconnecting. Hex wrench 174 and the
clamps in housing 176 index after each disconnection
operation to their starting positions.
Once rotating hex wrench 174 disconnects the terminal
segment of the process mandrel, the disconnected segment is
moved online (mechanically, by pistons) to tube extraction
ate 182 having extractor 184. Extractor 184 pulls mandrel
segment 186 out of tube 188. Disconnected mandrel segments,
when being drawn from composite tubes, are simultaneously
25 drawn throLIgll mold release bath 190. The composite tube 188
once freed can then be sent to storage, or alternatively,
sent to a riveting operation which rivets the metal sleeves
to the composite tubular members thereby completing
manufacture of the drive shaft member.
Figure 10 depicts composite tube drive shaft member 200
which is for use in the drive train of a vehicle classified
as a light truck. The drive shaft tube member 200 has been
made using the techniques discussed in connection with the
fabrication sequence of Figure 1. composite tube 202 carries
35 hollow metal sleeves 204, 206 inside its flared ends 208,
210. Hollow rightly sleeves 204, 206 are generally cylindrical
in configuration; Mach of sleeves 2U4, 206, however, has a
wall that thins toward the center of composite tube 202 with
an inner dianlet~r that is constant. because of this thinning
- 18 _ ~232435
of thy wall of the slaves 204, 206, there is about a 1 tax
per to each sleeve. Rivets 212, 214 respectively pass
through and around flared ends 208, 210 of composite tube 202
and through sleeves 204, 206 in fixing these sleeves 204, 206
in composite tube 202. Rivets 212, 2l4 are added after the
tube fabrication sequence of Figure 1 as a separate opera-
lion. Alternatively, sleeves such as sleeves 208, 210 can be
adhesively bonded to a composite tube such as tube 202 after
fabrication thereof.
Rivets 212, 214 each are disposed circumferential
about composite tube 202 in a pair of circles. Each circle
of rivets has seven rivets, making 28 rivets per drive shaft.
Figure lo diagrammatically depicts a wall portion of
tube member 200 of Figure 10 that includes a portion of
sleeve 206. The wall depicted in Figure lo typifies a wall
of a composite tube that can be made in accordance with this
invention; the filament in this wall is positioned for trays-
milting torque in the drive train of a motor vehicle that
would by classified as a light truck.
Thy wall depicted in Figure lo has distinct, but iota-
grated zones of continuous filament and resin. Zone A is
composed of four sub zones Al, A, A and A. Each of sub-
zones Al, A, A and A is a ply of E-glass filament in then-
most resin matrix. The angle at which the continuous glass
filaments are disposed in these sub zones is +45 or -45
(+30) relative to a line parallel to central longitudinal
axis 216 of the composite tube 202 of Figure 10. The fife-
mints in zone A were deposited at stations B, D, F and H in
the sequence of Figure 1.
Zone B comprises sub zones By and By spaced on either
side of zonk C in Figure loan Each of sub zones By and By
has a ply of substantially circumferential disposed contain-
use glass filaments. Those filaments in zone B are E-glass
and disposed desirably at an angle with an absolute value of
35 between about 82 and 88, normally between about 84 and
86~, relative to a lint parallel to central longitudinal axis
216 of tune Go The filaments in zone B were deposited at
stations J and N in the sequence of Figure 1.
~3243~
-- 19 --
zone C of Figure lo comprises carbon or graphite fiber
at an angle of zero greet (-i3) relative to a line parallel
to central Lyon urinal axis 2l6 of tube 202. These carbon
or graphite fibers are 36,000 filament. The filaments in
zone C wore deposited at station L in the sequence of Figure
l.
The filaments in composite tub 202 comprise between
about 50% and 60~ by volume of tube 202, the remainder being
a cross linked vinyl ester resin.
In an alternative embodinlent, zone B has but a single
sly of filament and this single ply is around the outside of
zone C. In a variation of this embodiment, zone A-has but a
single layer of filament, i.e. zones Al and A. In still
other applications of this invention, the filaments can be
positioned during manufacture to suit requirements of such
other applications.
