Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
I
This application is a division of Canadian Patent
Application No. ~30,871, filed June 21, 1983.
Lucy invention relates to manufacture of hollow, file-
Monterey composite tubes that can be used, for example, to
transmit torque in the drive train of motor vehicles. Fife-
Monterey composite tubes have been proposed for reduced weight
S shafts in the drive train of motor vehicles. See, for exam-
pie, US. Patents 4,17l,626; 4,236,3~6; 4,238,539; 4,238,540
and 4,289,557. See, also, "Development of an Advanced Come
posit Tail Rotor Drive shaft" by Zinberg et Al presented at
the Thea annual National Forum of the American Helicopter
lo Society, Washington, DO June l970.
Fabrication of composite tubes by applying fiber to a
cylindrical mandrel is known. See, 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 suck
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); 4,309,865 (Brunch et
at.) disclose tube making yrocPsses 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 fabricating devices for (it forming a resin and fiber
tube comprising continuous filamentary reinforcements about
said segmented mandrel passing there through (ii) hardening
said rosin and fiber tube around said segmented mandrel after
said forming; and (iii) s~vertng adjacent the juncture be-
tweet adj~c4ntly joined segments of said segmented mandrel the tubular product of said resin and fiber tube that has
hardened sufficiently for said severing; as this passage
. . . . _ . .
~32~
-- 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
Eros 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 to
a hollow, mass produced, filament wound composite tube suited
for transmitting -torque in a motor vehicle as par-t of the drive
train thereof, said tube in absence of end fittings joining
I
said tube to said drive train consisting essentially of
continuous filaments in a thermoses resin matrix said
continuous filaments disposed in resin and fiber zones
integrated together in the wall of said tube by said thermoses
resin matrix substantially along lines parallel to -the central
longitudinal axis of said tube wherein said resin and fiber
zones, proceeding radially from closest to farthest from said
center longitudinal axis consist essentially of said thermoses
resin matrix and: (a) inner glass filaments disposed (i) in one
or more inner glass layers and (ii) at angles, with respect to
a line drawn parallel to said longitudinal axis, between about
~30 and +55 and -30 and -55 in respective plies of said one
or more inner glass layers; (b) intermediate glass filaments
disposed (i) in a single intermediate glass ply, (ii) radially
between, and adjacent to, said inner glass layers and a single
graphite or carbon ply and (iii) substantially
circumferential in the wall around said tube; (c) graphite or
carbon filaments disposed (i) in said single graphite or carbon
ply, (ii) radially between, and adjacent to, said single
intermediate glass ply and a single outer glass ply and (iii)
at an angle, with respect to a line parallel to said
longitudinal axis, of zero degrees; (d) outer glass filaments
disposed (i) in said single outer glass ply and (ii)
substantially circumferential in the wall around said tube.
Also disclosed are: a method of manufacturing a hollow
composite tube, the subject matter or parent Canadian Patent
application No. 430,871, which matured to patent on October 14,
1986 as Canadian Patent Jo. 1,212,529; a machine that
manufactures composite tubes, the subject matter of Canadian
~32~
Patent application Jo. 514,909, a division of Canadian patent
application Jo. 430,871 filed contemporaneously with the
present application; and a segmented mandrel, -the subject
matter of Canadian Patent No. 51~,911, 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 9~.23Hz, 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 it disposed a-t a plus or minus first angle relative to
a line parallel to an axis and the second of which is disposed
a-t a second ankle of about the same magnitude as the first
angle but the negative
/
~=~
~23~
thereof relative to such line. ply" means a group of fife-
mints disposed at the substantially same angle in a geometric
plane concentric with a mandrel portion which plural 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
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 assay 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
resin applicator chamber for impregnating fiber carried by a
process mandrel portion passing through the chamber down-
stream from the 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
I
hardened resin and fiber produced in accordance with this in-
mention arid carried by a process mandrel portion downstream
from the portion of Figure 7.
Figure g 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. The mandrel segment being disconnected is
downstrearll of the process mandrel portion of Figure 8.
Figure 10 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 coïnposite of Figure 10.
Figure 1 shows the fabrication steps which result in
composite drive shaft tubes for light trucks in accordance
with this invention. The fabrication sequence is illustrated
in Figure l as a series of steps set forth in the order in
which the tubes asp 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 ox 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 segment 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 by the sequence of Figure 1.
t 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 longitudir,~l axis. (See Figure 2 for a cross-section
of two joined mandrel segments). Hand over hand clamps at
I
-- 7
station R continually pull the process mandrel away from
joining station A and through the other tube fabricating
stations that art downstream thereof.
A moving grip jaw at station prevents rotation of the
moving process mandrel. The grip jaw holds the process man-
duel while thy unconnected, fresh mandrel segment is spun
into locking engagement with, and becomes the rear segment
of, the process mandrel proceedinc3 as a train of seglnents
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 downstream 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 rota
able in the directiorl 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 thy process mandrel. There are four helical applique-
ions in the fabrication sequence of Figure 1, labeled B, D, F
and Al, 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 covered with a layer or layers of con-
tenuous foments, as desired. For example, two layers of
-- 8
continuous filamerlt can be deposited by stations B, Do F and
H. Unmaking light truck drive shaft tubes, each pair of the
stations deposits a layer of filament. The layer has a +45
ply and a -~5 ply where these ankles 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 .02~ and .334 lobs
of fiber per linear foot of the process mandrel. Each of
these station B, DO and H can utilize up to 80 rovings with
yields of 113 and 1~00 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 l 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 coralberry. (A
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 passing 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
blaze 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, I and o (and the other
stations) at any desired rate preferably between 1.5 and 6
feet per minute in the sequence being described. it 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.
Station J in the sequence of Figure 1 deposits dry fiber
around the process mandrel over the impregnated fixers there-
of as it proceeds from the impregnation at station I. Stay
lion J comprises a rotating hoop applicator wheel that no-
tats 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
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
dPscrib~d the hoop applicator spins around the process man-
duel at between about 18 and 72 rum in depositing a 1 inch
wide band of 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 more 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 they 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
rinks are offset from each other so that the yarns or rovings
are lazed all around the fiber covered and resin impregnated
process mandrel.
I
- 10 -
The yarns or rovings at station h 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 Graphite Together these filaments weigh between about
0.l~7 and U.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.
lo Station N (of the sequence of Figure l) wraps the long-
tudinally disposed filaments carried on the process mandrel
from station L with a hoop ply of dry filaments 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 ~80D and 90~ or between about -80 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
N, as described above.
The fiber and resin covered process mandrel, impregnated
at station o then proceeds therefrom to station P which in-
shuts cure of the thermosettable resin, station P being
shown in the sequence of Figure l.
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 resin 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 thermosettable resin such as
Darken from Dow Chemical Corp.
station Q of the sequence depicted in FicJure l comprises
infrared heaters. The heaters increase the outside skin
temperature to 200F. bank of five infrared heaters are
Jo I
monotype around a 6 foot long cylinder. Station Q eliminates
surface tack which may exist when curing thermosettable rosin
cor.tainin~ a styrenes monomer in air.
Some distance exists between station Q and station R.
S Station R of the sequence depicted in Figure 1 grips the
hardened resin tub proceeding from station Q. Station P
grips the composite tube sufficiently to pull it through the
proceedirlg stations. Station R has two land over hand grip-
ping clamps. The hand over hand gripping mechanism may be
lo purchased from Golds worthy Engr. of Torrance, Cal.
Station S of the process sequence depicted in Figure 1
severs the hardened tune 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 the 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
the 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 tube as it proceeds through station S.
After the tube is severed, the blades together translate
upstream to their starting position.
Station T of the process sequence identified in Figure 1
disconnects the 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 tune that
it carries. The downstream joined mandrel segment is then
disconnected from the rest of the 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-
vexed at station I) and spins it free of the moving upstream
train of joined mandrel segments. (See Figure 9 for schema-
tic Yo-yo of the mandrel segment disconnecting and tube
extracting device combination.)
23~
The disconnected mandrel segment carrying the cured come
posit tube proceeds to station 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
connect mandrel segment in an extraction die. The disco-
netted mandrel segment is pulled through the extraction die
stripping the cured composite tube. The disconnected mandrel
sec3inent 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. Thy 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 the 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.
The 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
conlposit~ 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, N, P, Q, R, S, T, U and V; different combinations
of fiber yield and numbers of rovings can also be employed in
any of these sequences.
Figures 2 through 9 illustrate equipment identified in
prevails description of the process sequence of Figure 1.
Figure 2 is a cross-section of the joined ends of two
cylindrical mandrel SegTnentS 10, 12 that are used in making
composite drive shaft tubes for certain light trucks in con-
section with the process sequence of Figure 1. Joined man-
duel segments 10, 12 have cylindrical steel sleeves lo, wish slip over their respective ends. Plastic sleeve 18
fits cylindrically about and between adjoining en portions
of steel sleeves 14, 16 and between segments 10, 12.
The opposite ends (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 male acme threads 22 for connecting
mandrel segment 12 to mandrel segment lo Mandrel segment 10
lo has socket 24 with threads 26 for receipt of threads 22 in
locking relation. mandrel segment it joins to mandrel sex-
mint 12 with relative rotation between them of between about
1 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-
ceded 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 seglilent lo leads mandrel segment 10 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 tube 32 becomes, with
sleeve 16 and a sleeve (not shown) at the other end 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
tube separated from mandrel segment lo Intermediate compost
tie tube 36 remains with mandrel segment 10 after disco-
section of mandrel segment 12 therefrom until stripping of
tube 34 from mandrel segnl~nt 10 at station U.
. . . .
Jo $
_ 14 -
Int~r~diate composite tube 36 has been cut out at tube
cutting station S. Plastic sleeve 18 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 I 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 380 The speed at
which wheels 40, 42 and consecluently rings assemblies 66, 68
rotate relative to the axial translation of process mandrel
portion 3B through these ring assemblies determines the angle
at which the fixers 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 9. 48, 50)
of filaments.
Figures 4 and PA schematically illustrate longitudinal
fixer 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 fixer passing from remote spools or creels (not
shown) through their respective offset holes 94, 96, 98 and
100. Holes 94, 96, 98 and 100 are respectively spaced about
segmented mandrel portion 84 in these rings 86, 88, 90, 92.
, . . , _ .. _ , .. . . ...
I
There are about 51 holes in each of the spaced disposition
rings 86, 88, 90, 92. Each individual hole in holes 94, 96,
I and loo receives up to about 36000 or more filaments.
Conduits 102, 104, 106, 108 lead from the creels to respect
live holes I 96, 98 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 ankle 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 wheels 114, 116 carry spools ll8, l20 about their respective
outer face peripheries 122, 124. Continuous filament feeds
from these spools to a rotating Eyelet (not shown) between
wheels 114, ll6 for depositing the filaments onto mandrel
portion 11~. i
The eyelet rotates about process mandrel portion 112
with wheels ll4, 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 circumfexentially
sealed at its mandrel entry and Pit orifices by rubber ring
seals l38t l40, respectively. Resin coroner 132 is filled
continuously with resin ~42 at inlet l44 with liquid resin at
a pressure of between about 4 ft. and 8 ft. resin head. Out-
let 146 can be used as overflow, if desired. The resin can
be any hard enable liquid resin and preferably is vinyl ester
thermosettable resin (e.g. Derakane*,from Dow Chemical Co.,
Midland, Michigan formulated with suitable peroxide catalyst
and maintainer at between about 60 and 90F. in chamber
l32. The use of vinyl ester resin with peroxide catalyst
gives thermosettable resins with appropriate pot lives (e.g.
between about 8 and 12 hours) for shift operations.
Figure 7 is a schetilatic illustration of induction heater
device 148 which is serving the function of curing thermoses-
table resin as described in reference the tube fabrication sequence 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
thy 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
I 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. tube
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 164, 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 yositionO
* denotes trade mark
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, threaded, hex wrench
l74 receives a flex heat portion of a forward mandrel segment,
such as Shari my socket end 25 of mandrel segment 10 in Fig-
use 2. Wr~llch 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
lo 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-
noted 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 off line (mechanically, by pistons) to tune extraction
vie 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 through 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 lo 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 ~iletal sleeves 204, 206 are generally cylindrical
in configuration; each of sleeves 204, 206, however, has a
wall that thins toward the center of composite tube 202 with
an inner diameter that is constant. Because of this thinning
I
- 18 -
of the wall of the sleeves 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 be classified as a light truck.
The wall depicted in Figure lo has distinct, but inked
grated zonks of continuous filament and resin. Zone A is
composed of four sub zones Al, A, A and A. Each of sub-
zones Al, I A and A is a ply of E glass filament in then-
most resin matrix. The angle at which the continuous glass
filaments art 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 Andy in
the sequence of Figure 1.
zone B comprises sub zones By and By spaced on either
side of zone C in Figure loan Each of sub zones By and By
has a ply of substantially circumferential disposed contain-
use glass filaments. These 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 little parallel to central longitudinal axis
216 of Taipei 202. Tll4 filaments in zone B were deposited at
stations J and N in the sequence of Figure 1.
I
-- 19 --
zone C of Figure lo comprises carbon or graphite fiber
at an angle of zero degrees (+3) relative to a line parallel
to central longitudinal axis 216 of tube 202. These carbon
or graphite fibers are 36,000 filament. The filaments in
zone C were deposited at station L in the sequence of Figure
l.
The filaments in composite tube 202 comprise between
about 50% and 60% by volume of tube 202, the remainder being
a cross linked vinyl ester resin.
In an alternative embodiment, 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 ye
positioned during manufacture to suit requirements of such
other applications.
