U.S. patent application number 09/250672 was filed with the patent office on 2001-08-23 for flexiable and reinforced tubing.
Invention is credited to KELLEY, GREGORY.
Application Number | 20010016728 09/250672 |
Document ID | / |
Family ID | 24952678 |
Filed Date | 2001-08-23 |
United States Patent
Application |
20010016728 |
Kind Code |
A1 |
KELLEY, GREGORY |
August 23, 2001 |
FLEXIABLE AND REINFORCED TUBING
Abstract
Disclosed here within is the method of manufacture of a
reinforced and flexible tube or catheter that can be used in a
variety of applications. The reinforced and flexible tube comprises
a thermoplastic tubular member that is surrounded by a helical coil
or braided member which is partially or completely embedded within
the outer surface of the tubular member. Alternatively, the
reinforced and flexible tube can comprise a thermoplastic tubular
member that which has a helical coil or braided member that is
partially or completely embedded within the inner surface of the
tubular member. The first method of embedding the metallic coil or
braided wire comprises the steps of engaging the metallic structure
over the outer surface of the tubular member, applying heat through
an appropriately sized mold to the outer surface of the tubular
member while creating a pressure differential between the inner
lumen and the outside surface of the tubular member for a specified
period of time. The second method of embedding the metallic coil or
braided wire comprises the steps of engaging the metallic structure
onto the outer surface of a mandrel, positioning the
mandrel/metallic structure within the lumen of the tubular member,
placing the tubular member within an appropriately sized mold,
applying heat through the mold to the tubular member while creating
a pressure differential between the inner lumen and the outside
surface of the tubular member for a specified period of time. The
flexible and reinforced tubular member resulting from these
processes contains a sequence of ridges on the inner surface of the
tubular member.
Inventors: |
KELLEY, GREGORY; (SAN DIEGO,
CA) |
Correspondence
Address: |
INTERVENTIONAL TECHNOLOGIES INC
3574 RUFFIN ROAD
SAN DIEGO
CA
92123
|
Family ID: |
24952678 |
Appl. No.: |
09/250672 |
Filed: |
February 16, 1999 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09250672 |
Feb 16, 1999 |
|
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08734682 |
Oct 21, 1996 |
|
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5879342 |
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Current U.S.
Class: |
604/525 ;
138/133 |
Current CPC
Class: |
B29L 2031/7542 20130101;
A61M 25/0012 20130101; A61M 25/005 20130101; A61M 25/0053 20130101;
B29L 2023/005 20130101; B29K 2105/06 20130101; B29D 23/001
20130101 |
Class at
Publication: |
604/525 ;
138/133 |
International
Class: |
A61M 025/00; F16L
011/00 |
Claims
I claim:
1. A reinforced tubular structure comprising: an elongated tubular
member having an outer surface and an inner surface and having a
lumen extending throughout; said tubular member being a composite
comprised of a polymeric material and at least one helical member,
said helical member either partially or completely embedded within
said polymeric material.
2. A reinforced tubular structure as defined in claim 1, further
comprising a multitude of protruding elements which in response to
bending or flexing stress, modify their configuration rather than
elongating and compressing said polymeric material.
3. A reinforced tubular structure as defined in claim 1, wherein
said protrusion being a ridge.
4. A reinforced tubular structure as defined in claim 1, wherein
said protrusion being a protrusion configured as a parallelogram,
helix, circle, trapezoid or triangle.
5. A reinforced tubular structure As defined in claim 1, wherein
said tubular member comprises multiple lumens. Regardless of the
particular application or design of the tubing, a coating may be
placed over the outer or inner surface of the tubular member.
Furthermore, the tubular member can be a single lumen or multiple
lumen design.
Description
PRIOR APPLICATIONS
[0001] This application is a divisional of application Ser. No.
08/734,682 filed on Oct. 21, 1996.
FIELD OF THE INVENTION
[0002] The present invention relates to a composite tubing for use
in a variety of applications and a method for manufacturing the
invention. The present invention pertains to a flexible and
reinforced tubing which can transmit rotational (i.e. torque) and
translational (i.e. push-pull) motion. In additional, the present
invention pertains to a method for manufacturing the reinforced and
flexible invention. The present invention is particularly, through
not exclusively, useful as a reinforced and flexible tube for use
in medical applications such as a guiding catheter or a catheter
with preferred torque, flexibility and pushable
characteristics.
BACKGROUND OF THE INVENTION
[0003] A large number of reinforced tubing devices have been
introduced for use in a wide variety of applications. For example,
flexible reinforced tubing is commonly used to transmit
translational motion (i.e., push-pull) or rotational motion (i.e.,
torque) from a control apparatus to an object located distally
which is to be manipulated or moved. An example of one such device
is the reinforced tubing disclosed in U.S. Pat. No. 5,101,682,
which can be used in medical applications and includes a
surrounding layer of electroplated material covering and bonded to
the tube. Another example of a reinforced tubing device is
disclosed in U.S. Pat. No. 3,769,813 for a resilient torque tube
that is reinforced with alternate layers of wire net and rubber and
is useful in vehicle transmissions.
[0004] Another important consideration in the design of reinforced
tubing devices is the need for adequate tubing resilience (i.e.,
resistance to permanent deformation, kinking, and buckling under
stress). Also, it may be desirable that the reinforced tubing be
highly flexible for certain applications, such as for providing a
conduit for fluid flow. It may also be desirable that the tubing
retain sufficient strength to function effectively as a torque
transmitter.
[0005] In one application, such as intravascular catheters used to
advance medical devices to the arterial system surrounding the
heart, there is a need for the catheter to be flexible but
nevertheless, also exhibit a certain amount of stiffness so that
the catheter may be advanced through various twists and turns
presented by the arterial system. Also, while the body of the
catheter must exhibit the desired characteristics of flexibility
and stiffness, the catheter lumen must have a low friction surface
so that an inner catheter or guidewire can be easily advanced
through the lumen. An example of one such device which can be used
in medical applications and discloses an invention which exhibits
the characteristics of flexibility and stiffness is U.S. Pat. No.
5,538,510 which employs coextruded tubular members to achieve the
desired results. The disadvantage of this coextrusion invention is
that the manufacturing process of this device is complex and has
the potential for relatively thick walls and large profiles.
[0006] While each of the reinforced tubing devices discussed above
can fulfill at least one of the above requirements, there is still
a need for a single reinforced tubing device which can be used
interchangeably in a variety of applications and which will
simultaneously provide all or several of the characteristics
mentioned above. To satisfy this need, the present invention
recognizes that a reinforced tubing device can be provided which is
relatively strong, flexible and thin walled, and which does not
easily kink, permanently deform, or buckle under stress.
[0007] Accordingly, it is an object of the present invention to
provide a thin walled reinforced tubing device which is both
relatively flexible and strong.
[0008] It is a further object of the present invention to provide a
reinforced tubing device that efficiently transmits translational
and rotational motion without easily buckling, kinking, or
permanently deforming.
[0009] Yet another object of the present invention is to provide a
reinforced tubing device that yields a specific inner lumen
configuration which reduces the overall internal contact area and
thereby reduces the frictional drag imparted to objects passing
through it.
[0010] Another object of the present invention is to provide a
method of reinforcing a tubular member which can vary certain
properties, such as flexibility, along the length of the
tubing.
[0011] Another object of the present invention is to provide a
method of fabricating flexible tubing from materials not known to
have flexible characteristics or from materials with a relatively
high modulus.
[0012] Another object of the present invention is to provide a
tubular structure containing a multitude of protruding elements
which, in response to bending or flexing stresses, modify their
configuration rather than and thereby minimize significant
elongation and compression of the base material.
[0013] Yet another object of the present invention is to provide a
reinforced tubing with relatively a thin wall and maintaining the
characteristics described in the above six paragraphs.
[0014] Another object of the present invention is to provide a
reinforced tubing device which can be used in a wide variety of
applications.
[0015] Yet another object of the present invention is to provide a
reinforced tubing device that is easy to use and relatively cost
effective to manufacture.
SUMMARY
[0016] For the foregoing reasons, there is a need for a flexible,
reinforced and relatively thin walled tubular member that
incorporates the features described herewith and that can be
inexpensively manufactured.
[0017] The present invention is directed to a tubular member that
has a continuous annular wall that defines an inner lumen and at
least one helical structural member that is embedded within the
outer or inner surface of the tube wall. The helical coil or
braided structure can be embedded to various depths; within the
outer surface or inner surface of the tubular member. It is also an
object of the present invention to vary the embedding depth or
pitch characteristics of the helical member along any portion of a
tubular member to modify the flexibility and torque characteristics
over the longitudinal length of the tube. Therefore, the present
invention yields a number of ridges or other shaped protrusions
projecting into the lumen. These protrusions function to reduce the
internal contact area and therefore reduce frictional drag when
another structure is being passed through the internal lumen.
[0018] One method of manufacturing the present invention includes
the steps of engaging a helical member, e.g., a braid or coil, onto
the outer surface of the tubular member to form a processing
composite tubular member having a first end, a second end, and at
least one inner lumen. The tubular member can be either a single or
multi-luminal configuration. The processing tubular member is
positioned in an appropriately sized heating mold, a system to
create a pressure differential is applied between the outer surface
of the processing tubular member and the inner lumen by engaging a
pressure source to the inner lumen of said tubular member, said
processing composite tubular member is then heated to a temperature
within a range for a first period of time, while either
simultaneously or after a second period of time, a first pressure
is applied to said lumen of said composite tubular member for a
third period of time, after which said first pressure is reduced to
a second pressure, and the composite tubular member is allowed to
cool, resulting in a reinforced tubular structure.
[0019] Another method of manufacturing the present invention
includes the steps of engaging a helical member, e.g., a braid or
coil, onto the outer surface of a mandrel and positioning this
helical member/mandrel assembly within the inner lumen of the
tubular member forming a processing composite assembly, said
processing composite assembly is then placed within an
appropriately sized heating mold, a system to create a pressure
differential is applied between the outer surface and the inner
lumen of the tubular member by engaging a vacuum source to the
inner lumen of the tubular member and supplying a pressure source
to the outer surface of the tubular member or, said processing
composite assembly is then heated to a temperature within a range
for a first period of time while either simultaneously or after a
second period of time, the pressure differential is created by
applying a first pressure to the outer surface of the tubular
member and a first vacuum to the inner lumen of the tubular member,
said pressure differential is applied for a third period of time,
after which the pressure differential is reduced to a null, and
said composite tubular member allowed to cool, resulting in a
processed composite tubular member.
[0020] During the fabrication process, the mold can be shaped such
that the processed reinforced tubular member is final configured
with one or more radii. in addition, the mold can be configured
such that the processed reinforced tubular member yields a
substantially circular, oval, triangular# or other geometric shape
in cross section.
[0021] After the reinforced tube is processed, either the outer
surface, the inner surface, or both surfaces, can be coated with a
suitable material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a perspective view of the novel reinforced tubing
in one intended environment, showing the tubing positioned in an
artery and in operative association with a balloon catheter
device.
[0023] FIG. 2 is a perspective/sectional view showing the tubular
member with the helical member, e.g., a coil or braid, in contact
with the outer surface of the tubular member and positioned within
a thermal source, and the lumen of the tubular member engaged with
a pressure source.
[0024] FIG. 3 is a sectional view showing the tubular member with
the helical member in contact with the outer surface of the tubular
member forming a pre-processed composite tubular member, the lumen
of the tubular member engaged with a pressure source and the
pre-processed composite tubular member positioned within a thermal
source;
[0025] FIG. 4 is a sectional view showing the processed reinforced
tubing with the helical member embedded in various depths within
the tubular member.
[0026] FIG. 5 is a sectional view showing the reinforced tubing
with the helical member embedded in a fixed depth into the tubular
member and demonstrating the multiple convex ridges protruding into
the lumen.
[0027] FIG. 6 is an magnified sectional view showing the
relationship of the tubular member with the embedded helical
member, e.g., a braid or coil;
[0028] FIG. 7 is a side elevational view showing the method of
calculating the pitch angle of the helical member.
[0029] FIGS. 8a, Bb, and 8c are side elevational views showing the
reinforced tubing in a triangular (8a), oval (8b) and square (8c)
configuration.
[0030] FIG. 9 is a side elevation view of the multiple lumen design
of the reinforced tubing.
[0031] FIG. 10 is a sectional view showing the tubular member with
a helical member, e.g., a coil or braid, engaged to a mandrel and
positioned within the lumen of the tubular member forming a
processing structure which is positioned within a thermal source
and connected to pressure differential sources.
[0032] FIG. 11 is a sectional view showing the reinforced tubing
with the coil or braid embedded in a fixed depth into the tubular
member and demonstrating the multiple convex ridges protruding into
the lumen and projecting out from the outer surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Initially referring to FIG. 1, it can be seen that a
reinforced tubing, generally designated 10, may be operatively
associated with various ancillary devices in various diverse
applications. For example, FIG. 1 shows tubing 10 operatively
associated with an angioplasty inflation/deflation apparatus 7 and
an expandable angioplasty balloon 14. In the application of tubing
10 shown in FIG. 1, tubing 10 is a guiding catheter for providing
access from the femoral artery to the coronary vasculature to
balloon catheter 14. In this application, the tubing 10 must be
flexible to minimize damage to the aorta and possess transmitting
torque capability to position the tip of the guiding catheter to
the orifice of a coronary artery. Tubing 10 is also a conduit for
communicating fluid to the coronary artery once properly
positioned. While FIG. 1 illustrates one potential application of
tubing 10, it is to be understood that the application shown in
FIG. 1 is merely exemplary. As a further example of a potential
application for this invention, tubing 10 could be used as a
connector between a fluid source and a fluid receiver for fluid
communication applications requiring a strong, relatively thin
walled yet flexible hose connector, or as a control cable and fluid
conduit in a surgical atherectomy apparatus.
[0034] Turning now to FIGS. 2 and 3, the details of preprocessed
reinforced tubing 10 can be seen. There, tubing 10 is shown to
include a hollow tubular member 30 in juxtaposition with the
helical member (braid or coil) 36 to form a pre-processed tubular
composite. FIGS. 2 and 3 also shows a processing mold 17 which is
in contact with thermal source (heater) 15 and which is in
juxtaposition with the preprocess tubular composite. Also shown is
a representation of a temperature control system 20 and a variable
pressure source 11.
[0035] As best shown in FIG. 2 and 3, the pre-processed tubular
member has a continuous, substantially cylindrical annular wall 31
which defines an inner surface 32 and an outer surface 29. Wall 31
of tubular member 30 also defines a central hollow lumen or
passageway 28, through which liquid or gas can flow in connection
with, for example, angioplasty surgery applications of tubing 10.
Importantly, the dimensions of tube 30 (and tubing 10) may be
established as appropriate for the particular application of tubing
10. It is to be understood, however, that the outer diameter, the
inside diameter and the thickness of the wall 31 of tube 30 may be
adjusted to meet the criteria of an appropriate application.
Furthermore, the length of tubing 10 may be established as
appropriate for the particular application of tubing 10. For
example, tubing 10 may have a length which can vary between a few
inches and several yards.
[0036] Additionally, tube 30 is preferably made of strong yet
flexible polymeric materials, such as polyamide, polybutylone
terephthalate, polyetherimide, polyethylene, polyethylene
terephthalate, polyethylene napthalate, or any combinations
thereof. It is not essential that the, base polymeric material have
flexible characteristics or have a low modulus. The process
disclosed herein will tender a high modulus, inflexible base
material to have characteristics which in the present invention,
greatly exceeds the flexibility of a tubular member that is merely
extruded using such a base material. As the skilled artisan will
appreciate, the material of tube 30 may also be selected to be
compatible with the particular application of tubing 10. For
example, certain applications of tubing 10 may dictate that the
material of tube 30 be chemically compatible with certain fluids
which may be communicated through passageway 28 of tube 30, and
further that the material of tube 30 be nontoxic and
nonoxidizin4.
[0037] Furthermore, tubular member can comprise a multiple lumen
configuration (FIG. 9). The multiple lumen configuration will have
the thin wall, flexible and reinforced characteristics similar to
the single lumen design yet have an assortment of lumens where each
lumen can have a different and independent function.
[0038] Referring to FIGS. 2 and 3 demonstrating the preprocessed
composite member and FIG. 4 demonstrating the post-processing
configuration, the helical member 36 is shown in juxtaposition to
outer surface 29 of tubular member 30. More particularly, as shown
in FIG. 4, helical member 36 is positioned on tubular member 30 to
form a succession of spaced apart coils 43 whose respective edges
do not contact each other. Also, although the present invention
uses a wire for helical member 36, it is to be understood that the
geometry of helical member 36 may be any geometry suitable for
providing structural support for tube wall 31, such as a flat
ribbon or triangular configuration. Importantly, helical member 36,
should be made of a material which, when helically is juxtaposition
to the outside surface of tubular member 30, provides sufficient
hoop strength to structurally strengthen tube wall 31. In the
present invention* helical member 36 is composed of tungsten or
stainless steel, but it is to be understood that other materials
may be used which fulfill the strength and bonding requirements
discussed above, such as molybdenum, cobalt, nickel, or
combinations thereof It is also within the scope of this invention
that non-metallic materials may be employed as the helical member
36, such as nylon, carbon or boron fibers, or aromatic polyamide
fibers (e.g. Kevlar.RTM.).
[0039] In addition to the material requirements of helical member
36 disclosed above, it will be recognized by the skilled artisan
that the dimensions and configuration of member 36 will have a
significant effect on the operational capabilities of tubing 10. On
the one hand, these variables must be selected to provide
sufficient structural support for tube wall 31. on the other hand,
(for certain applications of tubing 10) the variables must be
selected to minimize the wall thickness of tubing 10. For example,
when tubing 10 is to be used in the angioplasty surgery application
shown in FIG. 1, thickness of helical member 36 may range from one
half thousandth (0.0005")of an inch to twelve thousandth (0.012")
of an inch, preferably ranging from one to four thousandths
(0.001"-0.004") of an inch in diameter. The is preferred range is
desirable in human clinical applications to minimize the profile or
overall outside diameter while maximizing the lumen diameter of the
device to match dimensional limitations of the human vasculature.
For other applications which require even greater strength of
tubing 10, helical member 36 may be relatively thicker.
[0040] As the skilled artisan will also readily appreciate, an
angular pitch 41 between the successive coils 43 of helical member
36, can be selected to provide for flexibility as well as for
sufficient torque transmission characteristics in tubing 10. In
fact, the present invention envisions a pitch angle 41 (defined as
the angle between a line perpendicular to the longitudinal axis and
the slope of one of the coil or braid stands) along the length of
tubing 10 which can be varied between one (1) degree and ninety
(90) degrees, preferably between five (5) and forty five (45)
degrees, 40 flexibility and torque transmission requirements
dictate. For example, pitch angle 41 may be relatively high (about
forty five (45) degrees) at one end of tubing 10 for maximum tor a
transmission. Pitch 41 may then be gradually or suddenly decreased
to about five (5) degrees at the second end of tubing 10 to provide
for more flexibility of tubing 10 near either end or varied along
its length.
[0041] In one method of manufacturing the embodiment shown in FIGS.
4, 5 and 6, helical member 36 becomes embedded, from the outer
surface 29, into tube wall 31. Initially, helical member 36, being
a braid or coil, is engaged onto the outer surface 29 of the
tubular member 30 to form a preprocessed composite tubular member
having a first end, a second end, and an inner lumen. Then, the
pre-process composite is positioned in an appropriately sized
heating mold 17, whereby a pressure source is engaged to the inner
lumen 28 of tubular member 30. Heat is applied to the composite
tubular member using a temperature range for a specified period of
time. Typically the temperature range is dependent on the polymeric
material employed, and may range anywhere from 100 degrees
Fahrenheit to 880 degrees Fahrenheit depending on the polymeric
material. When tubing 10 is being used as a guiding catheter and
the polybutylene terephthalate material is employed, the preferable
range is from 350 degrees Fahrenheit to 420 degrees Fahrenheit. In
an another embodiment, for example, when tubing 10 is being used as
a torque tube in medical applications and the polyamide material is
employed, the preferable range is from 275 degrees Fahrenheit to
350 degrees Fahrenheit. Since various polymeric materials could be
utilized in this process, the temperature range is dependent on,
and therefore adjusted for, the polymeric material employed.
[0042] Either simultaneously or after a predetermined time period
has passed, a first pressure is applied to the lumen 28 of the
composite tubular member 30 to cause the pressure differential
across the tube wall. Typically the pressure range is dependent on
the diameter and wall thickness of the tubular member employed, and
therefore may range anywhere from 20 psi to 5000 psi depending on
specific parameters of the tube. When tubing 10 is being used as a
guiding catheter and the polybutylene terephthalate material is
employed, the preferable range is from 300 psi to 550 psi. in an
another embodiment, for example, when tubing 10 is being used as a
torque tube in medical applications and the polyamide material is
employed, the preferable range is from 450 psi to 650 psi. Since a
wide range of tubular diameter and wall thickness could be utilized
in this process, the pressure range is dependent on these
parameters.
[0043] After the processing time has expired, the first pressure is
reduced to a second pressure. Finally the composite is tubular
member 30 allowed to cool resulting in a processed reinforced
tubing 34.
[0044] It is to be appreciated that the processed structure
disclosed above results in the braid or coil member 36 becoming
embedded into the wall 31 of processed tubular member 34. As the
skilled artisan will also readily appreciate and as demonstrated on
FIG. 4, the temperature, pressure or time can be adjusted during
the process to result in varying the depth of which the coil or
braid 36 becomes embedded in wall 31 of processed tubular member
34. These process parameters may then be gradually or suddenly
reduced or increased along the length of the tubular member to
result in various depths that the coil or braid becomes embedded.
Furthermore, as the braid or coil member 36 becomes embedded into
the wall 31, one or more projecting elements protrude from the
inner surface 32 of tubular structure 30. such elements 38, as
shows in FIGS. 4 and 5, result in a ridge which conforms to and
surrounds the embedded helical member. It is also possible that
these elements can be formed in a specific configuration, such as a
parallelogram, trapezoid or triangle.
[0045] Importantly, the dimensions of tubular member 30 (and tubing
10) may be established as appropriate for a number of applications
which result in the formation of particular tubular member. For
example, when tubing 10 is being used As a guiding catheter for
angioplasty applications, inner diameter of tube 30 may range from
approximately thirty nine thousandth (0.039") of an inch to four
hundred and forty five thousandth (0.445") of an inch, preferably
from sixty thousandth (0.060") of an inch to one hundred and twenty
five thousandth (0.125") of an inch, and the outside diameter of
tube 30 may range from fifty three thousandth (0.053") of an inch
to four hundred and fifty eight (0.458") of an inch, preferably
from seventy nine thousandth (0.079") of an inch to one hundred and
forty four thousandth (0.144") of an inch. The preferred inside and
outside diameters are appropriate for currently marketed
angioplasty and interventional devices that would be used with the
guiding catheter application.
[0046] In another embodiment, for example, when tubing 10 is being
used as a torque tube in medical applications, inner diameter of
tube 30 may range from approximately twelve thousandth (0.012") of
an inch to four hundred and forty five thousandth (0.445") of an
inch, preferably from forty thousandth (0.040") of an inch to
seventy thousandth (0.070") of an inch, and the outside diameter of
tube 30 may range from sixteen thousandth (0.016") of an inch to
four hundred and fifty eight (0.458") of an inch, preferably from
fifty two thousandth (0.052") of an inch to ninety thousandth
(0.090") of an inch. The preferred diameters are appropriate for 30
currently marketed angioplasty and interventional devices.
[0047] It is to be understood that the processed structure
disclosed above results in several advantages. First, tubing 10 is
a flexible yet strong hollow and relatively thin walled tube which
can effectively transmit both translational motion and rotational
motion (i.e., torque). Thus, tubing 10 can be used as A control
cable or torque conveyor in a variety of applications. Second, the
structure disclosed above results in a tubing 10 which will not
readily kink or permanently deform when bent. Third, tubing 10 will
not readily buckle under tensile or compressive stress, such as
what may be generated when tubing 10 is being used to transmit
translational and/or rotational motion. Fourth, the present
invention does not require materials known to have flexible
characteristics or materials with a low modulus. Fifth, the present
invention provides a tubular structure containing a multitude of
protruding elements which, in response to bending or flexing
stresses, modify their configuration and thereby minimize
significant elongation and compression of the base material. Sixth,
the present invention provides a reinforce tubing device that
yields a specific inner lumen configuration which reduces the
overall internal contact area and thereby reduces the frictional
drag imparted to objects passing through the lumen.
[0048] Certain applications of tubing 10 may require that a coating
(not shown) be applied to the outer surface 33 of the processed
composite tubing 34. Suitable materials for such a coating can be
polyetherimid, polyethylene, polyurethane, silicone products,
parylene, or lubricous hydrophilic coatings.
[0049] In a second method of manufacturing the embodiment shown in
FIGS. 10 and 11, helical member 46 becomes embedded into tube wall
51 of tubular member 50 through the inner surface 52. Tubular
member 50 is defined by having a first end, a second end, and an
inner lumen 48. Initially, a helical member 46 e.g., braid is
engaged onto the exterior surface of mandrel 42 which is positioned
and centered within lumen 48 of tubular member 50. The pre-process
composite is then positioned in an appropriately sized heating mold
18. A system for creating a pressure differential is applied
between the outer surface 49 and the inner lumen 48, by engaging a
vacuum source 62 to the inner lumen 48 of tubular member 50 and
applying a pressure source to the outer surface 49 of tubular
member 50. As shown in FIG. 10, heating mold 18 is connected to a
variable pressure source 61 to create a pressure which engages the
outer surface 49 of tubular member 50. A spacer 44 functions to
seal the second end of heating mold 18. As a skilled artisan can
appreciate, several methods of obtaining a pressure differential
between the inner lumen 48 and outer surface 49 (across the wall)
of the tubular member 50 are available. Heat is applied from mold
18 to the composite tubular member into a temperature range for a
first period of time. Either simultaneously or after a second time
period, the pressure differential is created by applying a first
pressure to the outer surface of the composite tubular member 50
and a first vacuum to the inner lumen of the composite tubular
member 50. After the processing times have expired, the pressure
differential is reduced to a null and the composite tubular member
50 is allowed to cool. The mandrel is removed, resulting in a
processed reinforced tubing 53.
[0050] It is to be understood that the processed structure
disclosed above results in the braid or coil member 46 embedded
through the inner surface 52 and into the wall 51 of tubular member
50. As the skilled artisan will also readily appreciate, the
temperature, vacuum, pressure or time can be adjusted during the
process to result in varying the depth of which coil or braid 46
becomes embedded in wall 51 of tubular member 50. These process
parameters may then be gradually or suddenly reduced or increased
along the length of the tubular member to result in various depths
that the coil or braid becomes embedded.
[0051] The details of the operation of tubing 10 will vary
according to the particular application of tubing 10. When tubing
10 is to be used as a torque transmitter/control cable, tubing 10
is operatively associated with the particular control apparatus
being used, such as the apparatus 7 shown in FIG. 1, or a motor
throttle (not shown) or even a person's hand (not shown). Distal
end of tubing 10, in contrast, can be attached to the, mechanism
being manipulated, such as the angioplasty balloon 14 shown in FIG.
1. Translational motion and torque may then be transmitted through
tubing 10 from the particular Control apparatus being used to the
mechanism being manipulated. At the same time, because tube 30 is
hollow, fluid or gas may be communicated between the proximal end
and the distal of tubing 10.
[0052] While the particular reinforced tubing as herein shown and
disclosed in detail is fully capable of obtaining the objects and
providing the advantages herein before stated, it is to be
understood that it is merely illustrative of the presently
preferred embodiments of the invention and that to limitations are
intended to the details of construction or design herein shown
other than as described in the appended claims.
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