A heated shoe and cooled pressure roller assembly for composite prepreg application is provided. The shoe assembly includes a heated forward contact surface having a curved pressure surface. The following cooled roller provides a continuous pressure to the thermoplastic while reducing the temperature to approximately 5.degree. C. below glass transition temperature. Electric heating coils inside the forward portion of the shoe heat a thermoplastic workpiece to approximately 100.degree. C. above the glass transition. Immediately following the heated contact surface, a cooled roller cools the work. The end sharpened shape of the heated shoe trailing edge tends to prevent slag buildup and maintain a uniform, relaxed stress fabrication

Marchello, Joseph M.

Sandusky, Donald A.

A heated shoe and cooled pressure roller assembly for composite prepreg application is provided. The shoe assembly includes a heated forward contact surface having a curved pressure surface. The following cooled roller provides a continuous pressure to the thermoplastic while reducing the temperature to approximately 5 C below glass transition temperature. Electric heating coils inside the forward portion of the shoe heat a thermoplastic workpiece to approximately 100 C above the glass transition. Immediately following the heated contact surface, a cooled roller cools the work. The end sharpened shape of the heated shoe trailing edge tends to prevent slag buildup and maintain a uniform, relaxed stress fabrication

NASA Technical Reports Server

NASA CASE NO.
PRINT FIG.
NOElCE
The invention disclosed in this document resulted from research in aeronautical
and space activities performed under programs of the National Aeronautics and Space
Administration. The invention is owned by NASA and is, therefore, available for
licensing in accordance with the patent licensing regulations applicable to U.S.
Government-owned inventions (37 CFR 404.1 el seq.).
To encourage commercial utilization of NASA-owned inventions, it is NASA
policy to grant licenses to commercial concerns. Although NASA encourages
nonexclusive licensing to promote competition and achieve the widest possible
utilization, NASA will provide the necessary incentive to the licensee to achieve early
practical application of the invention.
Address informational requests for this invention to the Technology
Applications Team, NASA Langley Research Center, Code 200, Hampton, Virginia
23681-0001.
Address applications for license to the Patent Counsel Office, Mail Stop 212,
3 Langley Boulevard, Hampton, Virginia 23681-0001.
Serial No.: 08/411,231
Filed: 03/21/95
(NASA-Case-LAR-15259-1) CQNPOSITE
PREPREG APPLICATION DEVICE Patent
Application (NASA. Langley
Research Center) 14 p
laRC
N95-Z_|92
Unclas
Y
G3/24 0069679
https://ntrs.nasa.gov/search.jsp?R=19950020772 2020-06-17T23:51:40+00:00Z
LAR 15259-1-CU AWARDS ABSTRACT 
COMPOSITE PREPREG APPLICATION DEVICE 
A heated shoe and cooled pressure roller assembly for composite prepreg 
application is provided. The shoe assembly includes a heated forward contact 
surface having a curved pressure surface. The following cooled roller provides a 
continuous pressure to  the thermoplastic while reducing the temperature to 
approximately 5°C below glass transition temperature. Electric heating coils 
inside the forward portion of the shoe heat a thermoplastic workpiece to 
approximately 100°C above the glass transition. Immediately following the heated 
contact surface, a cooled roller cools the work. The end shape of the heated shoe 
tends to prevent slag buildup and maintain a uniform, relaxed stress fabrication. 
Inventor: Donald A. Sandusky 
Home address: f ?5-#8-Memmac-fraiI 1213 C h r i s t i n a  M i l l  Dr ive  
Employer: WM & Mary 
Inventor: Joseph M. Marchello 
Home address: 6 Rhoda Court 
Hampton, Virginia 23664 
SS#: 
Employer: 
0 
ODURF 
Initial Evaluator: 
Newark, DE 19711 
Serial No.: 081411,231 
Filed: March 21, 1995 
LAR 15259-1-CU -1 - PATENT APPLICATION
COMPOSITE PREPREG APPLICATION DEVICE
Origin_ of_the Invention
5 The invention described herein was made by contractor employees in
the performance of work under a NASA contract. In accordance with
35 USC 202, the contractor elected not to retain title.
10
Background of_the Invention
The invention is related to the field of composite fabrication and in
particular to devices providing product release, void compression and
residual stress management in thermoplastic composites.
15 Description of RelatedArt
20
25
The state of the art application devices were developed for thermoset
technology. They are not functional for thermoplastic in situ fabrication
because they cannot cause the appropriate heat transfer and squeeze flow
mechanisms to occur. Thermoplastics have become a material of
preference in certain fabrications, particularly lay-up of aerospace
structures. Thermoplastics exhibit beneficial characteristics including more
resilient and resistance to impact fractures, the ability to shape or mold,
resistance to heat and fire, and retention of these characteristics at high
temperatures. Recent thermoplastic matrix composites have withstood
frictional temperature approaching that required for Mach 2 flight.
To achieve this level of performance with thermoplastic components,
it is necessary to provide a material with uniform thickness, free of internal
flaws, uniformly compacted, and with a low and uniform level of residual
LAR 15259-1-CU
stress.
-2- PATENT APPLICATION
Summa[y_o[the Invention
5 It is an object of the present invention to provide a composite prepreg
application device which expels or compresses voids from thermoplastic
composites.
It is another object of the invention to provide a composite prepreg
application device which controls residual stress.
10 It is yet another object of the invention to provide a composite
prepreg application device with improved product release during composite
lay-up.
It is a further object of the invention to provide a composite prepreg
application device which facilitates melt flow of the incoming prepreg during
15 composite lay-up.
It is still another object of the invention to provide a composite
prepreg application device which applies both high temperature and high
pressure simultaneously during composite lay-up.
LAR 15259-1-CU -3- PATENT APPLICATION
It is another object of the invention to provide a composite prepreg
application device which applies both high pressure and a high cooling
gradient immediately following the high temperature and pressure lay-up.
Accordingly, the invention is a device for composite prepreg
5 application comprising a moving electrically heated shoe assembly having
an attached cooled roller. The electrically heated shoe assembly is operated
by a conventional robotic control mechanism known in the art. The special
shape of the shoe provides a substantial transverse pressure load as a
continuous pressure gradient to the prepreg material, that is, a continuously
10 increasing load. The heated shoe is maintained at a temperature above
(approximately 100°C above) the glass transition temperature for the
material being fabricated. Immediately following the tip of the heated shoe,
a cooled roller both applies pressure and reduces the temperature slightly
below (approximately 5°C below) the glass transition temperature. The
15 invention applies heat to a composite prepreg material with smoothly
increasing pressure so as to reach a temperature above glass transition for
purposes of causing wet outflow and consolidation and thereafter,
immediately applies cooling to below glass transition temperature while
maintaining a steady pressure on the material.
2O
Brief Description of theDrawings
25
For a more complete understanding of the present invention and for
further objects and advantages thereof, reference is now made to the
following description taken in conjunction with the accompanying drawings
in which:
FIG. 1 is a side view of the composite prepreg application device;
FIG. 2 is a side view of an alternative configuration of the application
device;
LAR 15259-1-CU -4- PATENT APPLICATION
FIG. 3 is a side view of the application device as installed on a
conventional robotic control mechanism; and
FIG. 4 is a cutaway side view of the application device.
5 Dstailed Description of the ln_ention
Referring now to Fig. 1, the composite prepreg application device,
designated generally by the reference numeral 10, is shown with its major
components. The device comprises an attachment base 11 which is
10 adapted for attachment to a conventional robotic lay-up machine. The
attachment base 11 has support arms 13 on either end for attaching a
pressure roller 15. A heated shoe assembly 16 is located on the fore
section of the attachment assembly 11. The heated shoe assembly uses an
electrical heater in the preferred embodiment, but any suitable heat source
15 may be substituted. The pressure roller 15 is cooled by a cooling fluid
delivered through support arms 13. During operation of the device, the
heated shoe assembly 16 raises the temperature of the paver-coated
prepreg tow 17 above the glass transition temperature, thereby providing
a molten plastic to the composite 19 immediately behind the tip 18 of the
20 heated shoe assembly. The heated shoe assembly has an elongated curving
tow guide having a sharpened tip or trailing edge. This shape provides the
steadily increasing pressure while the sharpened tip disperses slag
preventing any build-up. Immediately thereafter, the composite reaches the
pressure roller 15 where it is simultaneously compacted and cooled below
25 glass transition temperature. The process allows the production of high
quality, uniform lay-ups free of voids and free of variations in thickness or
surface smoothness.
Referring now to Fig. 2, an alternate embodiment 20 of the invention
is shown using a second cooling arrangement. The attachment base 21
LAR 15259-1 -CU -5- PATENT APPLICATION
contains the heated shoe assembly as in the first embodiment, however, the
pressure roller 25 has no internal cooling. Cooling is provided, instead, by
a cooling shoe 26 which receives a cooling fluid directly from the
attachment base 21. The temperature control of the incoming prepreg tow
5 17 is accomplished as in the preferred embodiment. The temperature of the
prepreg tow is raised above glass transition temperature, depicted by point
27, and then is immediately cooled, under pressure to a temperature below
glass transition temperature, depicted by point 28. During lay-up, the entire
lay-up structure may be moved, or the robotic machine may move the
10 application device. In the case of application device movement, the
direction of movement is to the left in each figure, depicted by arrow 29 in
Fig. 2.
The attachment of composite prepreg application device 10 when
installed on a typical robotic lay-up machine may be seen by reference to
15 Fig. 3. For attachment to a typical conventional robotic lay-up machine, the
attachment base is a block shaped to be held by the conventionally known
chucks commonly used on these machines. The block or bit forming the
attachment base is fitted with electrical ports and cooling ports for providing
heating energy and cooling energy to the applicator shoe and roller,
20 respectively. The robotic machine 30 is used to apply powder-coated
prepreg ribbon to a typical aerospace structure 31. As depicted here, the
device 10 in this embodiment applies multiple ribbons of prepreg tow 17.
By adapting the guide surface of the heated shoe, multiple side-by-side
strips of prepreg tow may be applied simultaneously.
25 A side section of the application device 10 in Fig. 4 shows the
internal components of the device. For reference, prepreg tow 17 is
referenced along with the attachment base 11 and the cooled roller 15
supported by arm 13 forming composite 19. Internally, a heating element
41 is located at the tip of the heated shoe. The upper portion 42 of the
LAR 15259-1-CU -6- PATENT APPLICATION
heated shoe assembly acts as a guide for the incoming prepreg tow 17. An
electrical connecting wire 43 provides a means of attaching the heating
element 41 to a power supply. The cooling liquid is supplied to the cooled
roller through an insulated area by coolant tube 45.
5 The advantage and features of the application device are numerous.
The device allows the immediate transition of a powder-coated prepreg tow
line to above glass transition temperature and immediately thereafter,
provides an under pressure temperature decrease to below glass transition
temperature. The result is a uniform application of the ribbon with a
10 uniformly filled material. Internal voids are minimized or eliminated. The
surface is uniformly even and the material thickness is likewise maintained
at a uniform value. The heated shoe assembly, having a curvilinear contact
surface, provides for a smoothly and steadily increasing pressure (a
continuous pressure gradient) on the work piece. This continuous pressure
15 gradient is applied while the heating of the work piece to approximately
100°C above the glass transition temperature for the particular work piece.
The prepreg lay-up is thereby maintained at a precise pre-selected pressure
during the glass transition. The cooling roller of the device is positioned
immediately behind the heated shoe contact surface. This positioning
20 allows pressure to be continuously applied to the work piece during both
heating through glass transition and then cooling down below glass
transition. There is no point during the heat up/cool down cycle where the
material is not under pressure with the exception of the very small physical
space separating the shoe contact surface and the roller. Additionally, the
25 trailing edge of the shoe tip tends to disperse any slag prior to any
significant buildup. As a result, a very high quality material is produced,
free of void area, and free of residual stresses.
Although the invention has been described relative to a specific
embodiment thereof, there are numerous variations and modifications that
5LAR 15259-1 -CU -7- PATENT APPLICATION
will be readily apparent to those skilled in the art in the light of the above
teachings. It is therefore to be understood that, within the scope of the
appended claims, the invention may be practiced other than as specifically
described.
What is claimed as new and desired to be secured by Letters Patent
of the United States is:
LAR 15259-1-CU PATENT APPLICATION
COMPOSITE PREPREG APPLICATION DEVICE
Abstractof the Invention
5 A heated shoe and cooled pressure roller assembly for composite
prepreg application is provided. The shoe assembly includes a heated
forward contact surface having a curved pressure surface. The following
cooled roller provides a continuous pressure to the thermoplastic while
reducing the temperature to approximately 5°C below glass transition
10 temperature. Electric heating coils inside the forward portion of the shoe
heat a thermoplastic workpiece to approximately 100°C above the glass
transition. Immediately following the heated contact surface, a cooled roller
cools the work. The end sharpened shape of the heated shoe trailing edge
tends to prevent slag buildup and maintain a uniform, relaxed stress
15 fabrication.
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English

Composite prepreg application device

I11111 11111111 111 11111 11111 11111 11111 111 11111 11111 11111 111111 11 11111 1111 
US005587041A 
United States Patent [191 [ I I ]  Patent Number: 5,587,041 
Sandusky et al. [45j Date of Patent: Dec. 24, 1996 
1541 COMPOSITE PREPREG APPLICATION 
DEVICE 
1751 Inventors: Donald A. Sandusky, Williamsburg; 
Joseph M. Marchello, Hampton, both 
of Va. 
[73] Assignee: The United States of America as 
represented by the Administrator of 
the National Aeronautics and Space 
Administration, Washington, D.C. 
[21] Appl. No.: 457,608 
[22] Filcd: Jun. 1, 1995 
Related U.S. Application Data 
1621 Division of Scr. No. 411,231, Mar. 21, 1995, abandoned. 
[Sl] Int. C1.6 ..................................................... B65H 81/00 
[52] US. C1. .......................... 156/441; 156/166; 156/169; 
[58]  Field of Search ..................................... 156/425, 433, 
1561175; 156/425; 156/433; 156/498; 156/574 
156/441, 523, 499, 498, 574, 166, 169, 
173, 175 
~561 References Cited 
U.S. PATENT DOCUMENTS 
4,804,509 2/1989 Angell, Jr. et al. ..................... 264/136 
4,915,771 4/1990 O’Brien et al. ......................... 156/574 
4,990,213 2/1991 Brown et al. ....................... 156/499 X 
4,992,133 2/1991 Border ................................ 156/499 X 
5,045,147 9/1991 Benson ct al. ...................... 156/498 X 
FOREIGN PATENT DOCUMENTS 
0463611 111992 European Pat. OK . 
OTHER PUBLICATIONS 
Ermert, W, et al, “Ru Reinforcing Plastics with robots?” 
Plastics Engineering, May 1981, pp. 37-46. 
Klein, Allen, “Automated tape laying”, Advanced Compos- 
ites, Jan./Feb. 1989, pp. 44-52. 
Primary Examiner-Jeff H. Aftergut 
Attorney, Agent, or Firm-George F. Helfrich 
[571 ABSTRACT 
A heated shoe and cooled pressure roller assembly for 
composite prepreg application is provided. The shoe assem- 
bly includes a heated forward contact surface having a 
curved pressure surface. The following cooled roller pro- 
vides a continuous pressure to the thermoplastic while 
reducing the temperature to approximately 5” C. below glass 
transition temperature. Electric heating coils inside the for- 
ward portion of the shoe heat a thermoplastic workpiece to 
approximately 100” C. above the glass transition. Immedi- 
ately following the heated contact surface, a cooled roller 
cools the work. The end sharpened shape of the heated shoe 
trailing edge tends to prevent slag buildup and maintain a 
uniform, relaxed stress fabrication. 
2 Claims, 4 Drawing Sheets 
28 27 
https://ntrs.nasa.gov/search.jsp?R=20080004848 2019-08-30T02:39:48+00:00Z
U.S. Patent Dec. 24, 1996 Sheet 1 of 4 5,587,041 
U.S. Patent Dec. 24, 1996 Sheet 2 of 4 5,587,041 
a3 cv 
U.S. Patent Dec. 24,1996 Sheet 3 of 4 5,587,041 
U.S. Patent Dec. 24, 1996 Sheet 4 of 4 5,587,041 
5,587,041 
1 
COMPOSITE PREPREG APPLICATION 
DEVICE 
ORIGIN OF THE INVENTION 
Thc invcntion dcscribcd herein was made by contractor 
cmployces in the performance of work under a NASA 
contract. In accordancc with 35 USC 202, the contractor 
clcctcd not to retain title. 
This is a divisional of application Scr. No. 08/411,231 
filcd on Mar. 21, 1995, now abandoncd. 
BACKGROUND OF THE INVENTION 
Thc invention is related to the field of composite fabri- 
cation and in particular to devices providing product release, 
void compression and residual stress management in ther- 
moplastic composites. 
DESCRIPTION OF RELATED ART 
Thc statc or the art application devices were dcveloped for 
thermosct technology. They arc not functional for thcrmo- 
plastic in situ rabrication because thcy cannot cause the 
appropriatc heat transfcr and squeeze flow mechanisms to 
occur. Thermoplastics have become a material of preference 
in ccrtain fabrications, particularly lay-up of aerospace 
structurcs. Thermoplastics exhibit beneficial characteristics 
including morc rcsilient and resistance to impact fractures, 
the ability to shapc or mold, resistance to heat and fire, and 
retention of these characteristics at high temperatures. 
Rccent thermoplastic matrix composites have withstood 
frictional temperature approaching that required for Mach 2 
flight. 
To achieve this level of performance with thermoplastic 
cornponcnts, it is necessary to provide a material with 
uniform thickness, free of internal flaws, uniformly com- 
pactcd, and with a low and uniform level of residual stress. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a 
composite prepreg application device which expels or com- 
presses voids from thermoplastic composites. 
It is another object of the invention to provide a composite 
prepreg application device which controls residual stress. 
It is yet another object of the invention to provide a 
composite prepreg application device with improved prod- 
uct release during composite lay-up. 
It is a further object of the invention to provide a com- 
posite prepreg application device which facilitates melt flow 
of the incoming prepreg during composite lay-up. 
It is still another object of the invention to provide a 
composite prepreg application device which applies both 
high temperature and high pressure simultaneously during 
composite lay-up. 
It is another object of the invention to provide a composite 
prepreg application device which applies both high pressure 
and a high cooling gradient immediately following the high 
temperature and pressure lay-up. 
Accordingly, the invention is a device for composite 
prepreg application comprising a moving electrically heated 
shoe assembly having an attached cooled roller. The elec- 
trically heated shoe assembly is operated by a conventional 
robotic control mechanism known in the art. The special 
shape of the shoe provides a substantial transverse pressure 
load as a continuous pressure gradient to the prepreg mate- 
2 
rial, that is, a continuously increasing load. The heated shoe 
is maintained at a temperature above (approximately 100" C. 
above) the glass transition temperature for the material being 
fabricated. Immediately following the tip of the heated shoe, 
a cooled roller both applies pressure and reduces the tem- 
perature slightly below (approximately 5" C. below) the 
glass transition temperature. The invention applies heat to a 
composite prepreg material with smoothly increasing pres- 
sure so as to reach a temperature above glass transition for 
I O  purposes of causing wet outflow and consolidation and 
thereafter, immediately applies cooling to below glass tran- 
sition temperature while maintaining a steady pressure on 
thc material. 
5 
15 BRIEF DESCRIPTION OF THE DRAWINGS 
For a more complete understanding of the present inven- 
tion and for further objects and advantages thereof, reference 
is now made to the following description taken in conjunc- 
tion with the accompanying drawings in which: 
FIG. 1 is a side view of the composite prepreg application 
device; 
FIG. 2 is a side view of an alternative configuration of the 
application device; 
FIG. 3 is a side view of the application device as installed 
on a conventional robotic control mechanism; and 
FIG. 4 is a cutaway side view of the application device. 
20 
25 
DETAILED DESCRIPTION OF THE 
30 INVENTION 
Referring now to FIG. 1, the composite prepreg applica- 
tion device, designated generally by the reference numeral 
10, is shown with its major components. The device com- 
35 prises an attachment base 11 which is adapted for attachment 
to a conventional robotic lay-up machine. The attachment 
base 11 has support arms 13 on either end for attaching a 
pressure roller 15. A heated shoe assembly 16 is located on 
the fore section of the attachment assembly 11. The heated 
40 shoe assembly uses an electrical heater in the preferred 
embodiment, but any suitable heat source may be substi- 
tuted. The pressure roller 15 is cooled by a cooling fluid 
delivered through support arms 13. During operation of the 
device, the heated shoe assembly 16 raises the temperature 
45 of the paver-coated prepreg tow 17 above the glass transition 
temperature, thereby providing a molten plastic to the com- 
posite 19 immediately behind the tip 18 of the heated shoe 
assembly. The heated shoe assembly has an elongated curv- 
ing tow guide having a sharpened tip or trailing edge. This 
50 shape provides the steadily increasing pressure while the 
sharpened tip disperses slag preventing any build-up. Imme- 
diately thereafter, the composite reaches the pressure roller 
15 where it is simultaneously compacted and cooled below 
glass transition temperature. The process allows the produc- 
55 tion of high quality, uniform lay-ups free of voids and free 
of variations in thickness or surface smoothness. 
Referring now to FIG. 2, an alternate embodiment 20 of 
the invention is shown using a second cooling arrangement. 
The attachment base 21 contains the heated shoe assembly 
60 as in the first embodiment, however, the pressure roller 25 
has no internal cooling. Cooling is provided, instead, by a 
cooling shoe 26 which receives a cooling fluid directly from 
the attachment base 21. The temperature control of the 
incoming prepreg tow 17 is accomplished as in the preferred 
65 embodiment. The temperature of the prepreg tow is raised 
above glass transition temperature, depicted by point 27, and 
then is immediately cooled, under pressure to a temperature 
5 3 87,04 1 
3 4 
below glass transition temperature, depicted by point 28. pressure (a continuous pressure gradient) on the work piece. 
During lay-up, the entire lay-up structure may be moved, or This continuous pressure gradient is applied while the 
the robotic machine may move the application device. In thc heating of the work piece to approximately 100" C. above 
case of application device movcrncnt, thc direction of move- the glass transition ternperaturc for the particular work piece. 
mcnt is to the left in each figurc, depicted by arrow 29 in 5 The prepreg lay-up is thereby maintained at a precise 
FIG. 2. prc-selected pressure during the glass transition. The cooling 
The attachrncnt of cornpositc prcpreg application device roller of the device is positioned immediately behind the 
10 when installed on a typical robotic lay-up machine may heated shoe contact surfacc. This positioning allows pres- 
be Seen by reference to FIG. 3. For attachment to a typical sure to be continuously applied to thc work piece during 
conventional robotic lay-up machinc, the attachment base is 10 both heating through glass transition and then cooling down 
a block shaped to be held by the ConVentionallY known below glass transition. There is no point during the heat 
forming the attachment basc is fitted with electrical ports with the exception of the very physical space sepa- 
the trailing edge of the shoe tip tends to disperse any slag energy to the applicator shoe and rollcr, respcctively. The 15 robotic machine 30 is used to apply powder-coated prepreg prior to any significant buildup. As a result, a very high ribbon to a typical aerospace structure 31. As depicted here, 
the device in this embodiment applies multiple ribbons of 
prepreg tow 17. By adapting the guide surface or the heated 
shoe, multiple side-by-side 
applied simultaneously. 
A side section of the application device 10 in FIG. 4 
shows the internal cornponcnts of the device. For rcfcrencc, 
prcpreg tow 17 is referenced along with the attachment basc 
11 and the cooled roller 
composite 19. Internally, a heating element 41 is located at 
the tip of the heated shoe. Thc upper portion 42 of the heated 
shoe assembly acts as a guide for the incoming prepreg tow 
attaching the heating element 41 to a power supply. The 30 
cooling liquid is supplied to the cooled roller through an 
insulated area by coolant tube 45. 
The advantage and features of the application device are 
numerous. The device allows thc immediate transition of a 35 
powder-coated prepreg tow line to above glass transition 
tcmpcraturc and immediately thereafter, provides an under 
pressure temperature decreasc to below glass transition 
temperature. The result is a uniform application of the 
ribbon with a uniformly fillcd material. Internal voids are 4o 
minimized or eliminated. The surface is uniformly even and 
the material thickness is likewise maintained at a uniform 
value. The heated shoe assembly, having a curvilinear con- 
chucks commonly used on these machines. The Or bit up/coo] down cycle where the material is not under pressure 
and ''ling Ports for providing heating and rating the shoe surface and the roller. Additionally, 
quality material is produced, free of void area, and free of 
stresses. 
of prepreg tow may be 20 Although the invention has been described relative to a 
specific embodiment thereof, there are numerous variations 
and modifications that will be readily apparent to those 
skilled in the art in the light of the above teachings. It is 
therefore to be understood that, within the scope of the 
supported by arm 13 forming 25 appended claims, the invention may be practiced other than 
as specifically described. 
as new and desired to be secured by 
Letters Patent of the United States is: 
What is 
17. An electrical connecting wire 43 provides a means of 1. A device for prepreg comprising: 
an attachment base having means for attaching to a 
conventional robotic lay-up machine and having an 
electrical supply and cooling fluid supply; 
a heated shoe assembly attached to said attachment base 
and enclosing a means for heating said shoe assembly; 
and 
a pressure roller rotatably attached to said attachment 
base, said roller having a means for cooling which 
comprises an external cooling shoe. 
2. A device for applying composite prepreg as in claim 1 
wherein said external cooling shoe comprises a cooling shoe 
having an internal chamber for receiving a cooling fluid. 
tact surface, provides for a smoothly and steadily increasing * * * * *  


Composite prepreg application device

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