U.S. patent application number 09/888920 was filed with the patent office on 2001-12-06 for integral hub and strain relief.
Invention is credited to Arnold, John E. JR., Berg, Todd A., Holman, Thomas J., Olson, Gregory K..
Application Number | 20010049519 09/888920 |
Document ID | / |
Family ID | 23834253 |
Filed Date | 2001-12-06 |
United States Patent
Application |
20010049519 |
Kind Code |
A1 |
Holman, Thomas J. ; et
al. |
December 6, 2001 |
Integral hub and strain relief
Abstract
A hub assembly for a catheter tube having a lumen therethrough.
The hub assembly includes a hub portion having a proximal end and a
distal end, and an integral connector disposed at the proximal end.
A lumen is defined through the hub portion extending from the
proximal end to the distal end. The strain relief includes a
proximal end and a distal end is disposed at the distal end of the
hub portion. The proximal end of the strain relief can be
integrally connected to the distal end of the hub portion. The
strain relief is preferably more flexible than the hub portion. The
strain relief defines a passage configured to receive the catheter
such that a lumen through the hub portion is in fluid communication
with the catheter tube lumen.
Inventors: |
Holman, Thomas J.;
(Minneapolis, MN) ; Arnold, John E. JR.;
(Minneapolis, MN) ; Olson, Gregory K.; (St. Louis
Park, MN) ; Berg, Todd A.; (Lino Lakes, MN) |
Correspondence
Address: |
Glenn M. Seager
CROMPTON, SEAGER & TUFTE, LLC
Suite 895
331 Second Avenue South
Minneapolis
MN
55401
US
|
Family ID: |
23834253 |
Appl. No.: |
09/888920 |
Filed: |
June 25, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09888920 |
Jun 25, 2001 |
|
|
|
08971456 |
Nov 17, 1997 |
|
|
|
6273404 |
|
|
|
|
08971456 |
Nov 17, 1997 |
|
|
|
08461867 |
Jun 5, 1995 |
|
|
|
Current U.S.
Class: |
604/534 ;
128/912; 604/525; 604/905 |
Current CPC
Class: |
B29C 45/14598 20130101;
B29L 2031/7542 20130101; B29C 70/72 20130101; A61M 25/0009
20130101; A61M 25/0097 20130101; A61M 2025/0098 20130101 |
Class at
Publication: |
604/534 ;
604/525; 604/905; 128/912 |
International
Class: |
A61M 025/00 |
Claims
What is claimed is:
1. A hub assembly for a catheter tube having a lumen therethrough,
the hub assembly comprising: a hub portion having a proximal end
and a distal end, and including an integral connection disposed at
the proximal end, and a lumen defined therethrough extending from
the proximal end to the distal end; and a strain relief having a
proximal end and a distal end, the strain relief being disposed at
the distal end of the hub portion and the proximal end of the
strain relief being integrally connected to the distal end of the
hub portion, the strain relief defining a passage configured to
receive the catheter tube such that the lumen through the hub
portion is in fluid communication with the catheter lumen.
2. A hub assembly in accordance with claim 1, wherein the lumen
extending through the hub portion has a wall having an average wall
thickness and the strain relief passage has a wall having an
average wall thickness, and the average wall thickness of the hub
portion is greater than the average wall thickness of the strain
relief passage.
3. A hub assembly in accordance with claim 2, wherein the wall
thickness of the passage generally decreases from the strain relief
proximal end to the strain relief distal end.
4. A hub assembly in accordance with claim 3, wherein a plurality
of grooves extend into the passage wall generally transversely
toward the passage.
5. A hub assembly in accordance with claim 4, wherein the grooves
extend through the wall into the passage.
6. A hub assembly in accordance with claim 4, wherein the grooves
are disposed in a plurality of sets, each set including two
grooves, the two grooves within each set being disposed generally
within the same plane to define a transverse hinge in the strain
relief.
7. A hub assembly in accordance with claim 3, wherein the strain
relief includes a generally helical portion extending from
proximate the proximal of the strain relief to proximate the distal
end of the strain relief.
8. A hub assembly in accordance with claim 1, wherein the connector
is a threaded connector.
9. A hub assembly in accordance with claim 1, wherein the hub
portion includes transversely extending wings.
10. A hub assembly in accordance with claim 1, wherein the hub
portion and the strain relief portion comprise the same
material.
11. A hub assembly in accordance with claim 10, wherein the
material comprises nylon.
12. A hub assembly in accordance with claim 10, wherein the
material comprises PEBA.
13. A hub assembly in accordance with claim 10, wherein the
material comprises polycarbonate.
14. A hub assembly in accordance with claim 1, further comprising:
an angled port integrally connected to, and extending from, the hub
portion.
15. A hub assembly for a catheter tube having a lumen therethrough,
the hub assembly comprising: a hub portion having a proximal end
and a distal end, and including an integral connection disposed at
the proximal end, and a lumen defined therethrough extending from
the proximal end to the distal end; and a strain relief having a
proximal end and a distal end, the strain relief being disposed at
the distal end of the hub portion and the proximal end of the
strain relief being integrally connected to the distal end of the
hub portion, the strain relief being more flexible than the hub
portion, the strain relief defining a passage including a wall, the
passage configured to receive the catheter tube such that the lumen
through the hub portion is in fluid communication with the catheter
lumen.
16. A hub assembly in accordance with claim 15, wherein a plurality
of grooves extend into the passage wall generally transversely
toward the passage.
17. A hub assembly in accordance with claim 16, wherein the grooves
extend through the wall into the passage.
18. A hub assembly in accordance with claim 16, wherein the grooves
are disposed in a plurality of sets, each set including two
grooves, the two grooves within each set being disposed generally
within the same plane to define a transverse hinge in the strain
relief.
19. A hub assembly in accordance with claim 15, wherein the strain
relief includes a generally helical portion extending from
proximate the proximal end of the strain relief to proximate the
distal end of the strain relief.
20. A hub assembly in accordance with claim 15, wherein the
connector is a threaded connector.
21. A hub assembly in accordance with claim 15, wherein the hub
portion includes transversely extending wings.
22. A hub assembly in accordance with claim 15, wherein the hub
portion and the strain relief portion comprise the same
material.
23. A hub assembly in accordance with claim 22, wherein the
material comprises nylon.
24. A hub assembly in accordance with claim 22, wherein the
material comprises PEBA.
25. A hub assembly in accordance with claim 22, wherein the
material comprises polycarbonate.
26. A hub assembly in accordance with claim 15, further comprising:
an angled port integrally connected to, and extending from, the hub
portion.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention pertains generally to the field of
catheters and, more particularly, to hub or manifold assemblies
connected to the proximal end thereof.
[0002] Catheters, such as guide catheters, diagnostic catheters and
therapeutic catheters, for example, angioplasty and atherectomy
catheters generally comprise a flexible tube having a permanently
connected hub assembly at one end of the tube. The hub assembly
often includes a hub and a strain relief. The hub generally
includes a connector for connecting the catheter to a Y-adaptor,
inflation device or the like. The strain relief generally extends
from the hub along a portion of the catheter tube to provide a
transition in flexibility between the hub and the tube.
[0003] Prior hub assemblies utilized a two piece construction, for
example, the hub was attached to an end of the catheter tube and
then the strain relief was attached in a secondary process. The
primary reason for the two piece design was the different functions
of the hub and strain relief required different materials or
material properties. The hub is required to be harder material to
withstand forces applied to the connector. The strain relief,
however, must provide a stiffness transition from the hub to the
catheter shaft. The strain relief material is typically soft and
flexible to provide kink-resistance and added support to the
catheter shaft proximate the hub.
[0004] One such hub assembly is disclosed by Wijkamp et al. in U.S.
Pat. No. 5,167,647. In one embodiment, a tubular strain relief is
injection molded around one end of the catheter. After the strain
relief has hardened, a hub is secured to the strain relief.
Alternately, an end of the catheter may be inserted into a hub. The
hub and catheter can then be placed into a mold to form the strain
relief around the end of the catheter and between the catheter and
the hub. Wijkamp et al. also discloses simultaneously molding both
the hub and the strain relief from two different materials.
[0005] Prichard et al., in U.S. Pat. No. 5,380,301, also disclose a
prior hub assembly. Prichard et al. disclose a hub formed of a
material having a relatively high durometer hardness in comparison
to the catheter. The strain relief is preferably formed of a
material having a flexibility and durometer hardness which is
greater than that of the catheter, but less than that of the hub.
The hub is first separately molded, then an end of the catheter is
inserted into the hub. Then both the hub and the portion of the
catheter proximal the hub are placed in a mold. As disclosed by
Wijkamp et al., the strain relief is then molded around the
catheter and between a portion of the hub and the catheter. The hub
also includes openings into which molten strain relief material
flows to form a mechanical bond between the strain relief and the
hub.
SUMMARY OF THE INVENTION
[0006] The present invention pertains to a hub assembly including
an integrally formed hub and strain relief. The hub assembly can be
insert molded in a single mold using one injection process and a
single material. The material can be sufficiently hard for use in
forming the hub. The desired relatively greater flexibility of the
strain relief is achieved by modifying the geometry of the strain
relief.
[0007] In a preferred embodiment, the hub assembly in accordance
with the present invention is for a catheter having a lumen
therethrough. The hub assembly includes a hub portion having a
proximal end and a distal end. An integral connection is disposed
at the proximal end. A lumen defined through the hub portion
extends from the proximal end to the distal end.
[0008] A strain relief having a proximal end and a distal end is
disposed at the distal end of the hub portion. The proximal end of
the strain relief is integrally connected to the distal end of the
hub portion. The strain relief defines a passage configured to
receive the catheter such that the lumen through the hub portion is
in fluid communication with the catheter lumen.
[0009] The lumen extending through the hub includes a wall having
an average wall thickness. The strain relief passage also has a
wall having an average wall thickness. In a preferred embodiment,
the average wall thickness of the hub portion is greater than the
average wall thickness of the strain relief passage. In one
embodiment, the wall thickness of the passage generally decreases
from the strain relief proximal end toward the strain relief distal
end.
[0010] In a preferred embodiment, a plurality of grooves extend
into the passage wall generally transversely toward the passage.
The grooves can extend through the wall into the passage. The
grooves can be disposed in a plurality of sets, each set including
two grooves. The two grooves within each set can be disposed
generally within the same plane to define a point of flexibility or
transverse hinge in the strain relief. In an alternate embodiment,
the strain relief can include a generally helical portion. The
helical portion preferably extends from proximate the proximal end
of the strain relief to proximate the distal end of the strain
relief.
[0011] In an alternate embodiment, the hub portion may include an
angled port. The angled port, hub portion and strain relief portion
can be integrally formed or connected by insert molding to form a
manifold for an angioplasty catheter. The angled port defines a
lumen in fluid communication with the lumen defined through the hub
portion, and consequently the port is also in fluid communication
with the lumen of the catheter tube held within the strain relief
portion. If the angioplasty catheter is an over-the-wire catheter,
a separate guide wire tube defining a guide wire lumen can extend
through the catheter tube defining an inflation lumen between the
catheter tube and the guide wire tube therein. The tube defining
the guide wire lumen can include a separate hub portion connectable
to the proximal end of the hub portion of the manifold.
[0012] The connector can be a threaded connector. The hub portion
can include transversely extending wings. The hub portion, the
strain relief portion and angled port can be made from the same
material, such as nylon, PEBA (polyether block amide polymer,
commercially available under the trade name PEBAX), polycarbonate
or another material having similar properties.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 discloses a perspective view of a hub assembly in
accordance with the present invention;
[0014] FIG. 2 discloses a cross-section of the hub assembly of FIG.
1;
[0015] FIG. 3 discloses a perspective view of an alternate
embodiment of a hub assembly in accordance with the present
invention;
[0016] FIG. 4 discloses a perspective view of an alternative
embodiment of the hub assembly in accordance with the present
invention including an angled port forming a manifold;
[0017] FIG. 5 discloses a perspective view of a hub for a guide
wire tube insertable into the manifold of FIG. 4; and
[0018] FIG. 6 discloses a perspective view of the manifold of FIG.
4 and the hub and guide wire tube of FIG. 5 inserted therein.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Referring now to the drawings wherein like reference
numerals refer to the same elements throughout the several views, a
hub assembly in accordance with the present invention is referred
to generally by reference numeral 10 in FIG. 1. Hub assembly 10 is
preferably connectable to an end of a catheter tube 12 which has a
lumen 14 extending therethrough. Catheter hub assembly 10 has an
axial length defined along the section line 2-2 shown in FIG. 1.
The proximal end of hub portion 16 includes an integral connector
18. A strain relief 20 having a proximal end 22 and distal end 24
is integrally connected at proximal end 22 to the distal end of hub
portion 16. Strain relief 20 preferably has a flexibility between
that of hub portion 16 and catheter tube 12. Strain relief 20
includes a passage 26 which has a lumen wall 27. Passage 26 extends
from distal end 24 to proximal end 22. Passage 26 is configured to
receive an end of catheter tube 12.
[0020] Integral connector 18 of hub portion 16 preferably includes
threads 28 for threadable connection to a Y-adaptor, inflation
device or other devices as well known in the medical arts. Rather
than threads 28, connector 18 could include a transversely
extending flange, bayonets, or other connector means.
[0021] Hub portion 16 preferably includes transversely extending
wings 30. Hub portion 16 can also include additional texturing
provided by a raised portion such as rectangular print pad 32. An
operator can push against the sides of wing 30 to rotate hub
assembly 10 to, for example, thread integral connector 18 into a
Y-adaptor or other device or rotate catheter tube 12 for some
therapeutic or diagnostic purpose. Similarly, the texturing or hub
portion 16 provides a rough surface to assist an operator to grip
hub assembly 10.
[0022] Referring now to FIGS. 1 and 2, strain relief 20 can include
grooves 36 extending transversely into strain relief 20 toward
passage 26. The width and spacing of grooves 36 may be varied to
effect the flexibility of strain relief 20. Grooves 36 may be
arranged in transversely oppositely disposed sets of two, for
example, grooves A and B. Each groove within a set can extend
through strain relief 20 to passage 26 leaving a thin portion 38 of
strain relief 20 disposed between the oppositely disposed grooves
36. Grooves 36 need not extend through to passage 26, but not
extending grooves 36 through to passage 26 will reduce the
flexibility of strain relief 20. Strain relief 20 is preferably
more flexible at distal end 24 than at proximal end 22.
[0023] Thin portion 38 provides a point of flexibility or
transverse hinge in strain relief 20. For example, as a generally
transverse bending force is applied to strain relief 20, grooves on
the opposite side of strain relief 20 from the bending force will
tend to close as grooves on the same side of the strain relief as
the force tend to open. Because a bending force may be applied to
any side of strain relief 20, it is preferable to vary the
orientation of grooves 36 and thin portions 38 around strain relief
20. For example, as shown in FIGS. 1 and 2, each successive set of
grooves 36 is rotated 90.degree. from the preceding set.
[0024] Referring now to FIG. 2, a lumen 40 having a luminal wall 41
is shown extending from the proximal end to the distal end of hub
portion 16. Lumen 40 is in fluid communication with catheter lumen
14. The extreme end of catheter tube 12 includes a transversely
flared portion 42 embedded in wall 41 of lumen 40. In a preferred
embodiment of hub assembly 10, to provide greater flexibility of
strain relief 20 relative to hub portion 16, the average thickness
of wall 41 is greater than the average thickness of strain relief
wall 27. The thickness of wall 27 may also taper between proximal
end 22 and distal end 24 of strain relief 20.
[0025] FIG. 3 is a perspective view of an alternative embodiment of
a hub assembly 100 in accordance with the present invention. Hub
assembly 100 includes a hub portion 102 having an integral
connector 104. Hub assembly 100 includes a strain relief 106 which
has a proximal end 108 and a distal end 110 and a wall 111. Strain
relief 106 is formed in a helical shape defining a passage 112
which is configured to receive an end of a catheter tube. The helix
of strain relief 106 includes a series of bends 114. Each bend 114
is preferably spaced from the adjacent bend 114. The space between
the bends provides a point of flexibility or hinge in strain relief
106. Other than the strain relief 106, hub assembly 100 can in all
respects be similar to hub assembly 10. The average thickness of
strain relief wall 111 can be less than the average wall thickness
of the lumen through hub portion 102.
[0026] The hub assembly of the present invention may be modified by
including an angled port 200 to form a manifold 202. Manifold 202
includes a hub portion 204 having a proximal end and a distal end
and an integral connector 206 at the proximal end. Connector 206
can include two oppositely disposed tabs 208, each including an
opening 210 therethrough. Integrally connected to the distal end of
hub portion 204 is a strain relief 212. The strain relief 212
includes an arrangement of grooves 214 substantially similar to the
arrangement of grooves 36 of strain relief 20.
[0027] Angled port 200 defines a lumen 216 extending therethrough
to a lumen 218 extending through hub 204. An end of a catheter tube
220 extends through a passage 222 defined by strain relief 212 into
lumen 218 of hub portion 204. The extreme end of tube 220 can be
anchored in hub portion 204 in the same manner as transversely
flared portion 42 of hub assembly 10 described above. The end of
tube 220 is anchored within hub 204 distally of the opening of
lumen 216 of angle port 200 such that the lumen defined by tube 220
is in fluid communication with port lumen 216 and lumen 218 of hub
portion 204.
[0028] FIG. 5 shows a hub 224 affixed to an end of a guide wire
tube 226. Hub 224 includes a longitudinally extending lumen 228 in
fluid communication with a guide wire lumen through guide wire tube
226. The end of tube 226 within hub 224 may be anchored like flared
end 42 of hub assembly 10 described above. Hub 224 includes an
insertable portion 230 and two oppositely disposed bayonets 232
(one of which is hidden from view in FIG. 5).
[0029] As shown in FIG. 6, guide wire tube 226 has been inserted
into catheter tube 220 through hub portion 204 of manifold 202.
Insertable portion 230 is inserted into lumen 218 of hub portion
204 such that bayonets 232 are inserted through holes 210 of tabs
208 to connect hub 224 to manifold 202. As known to those skilled
in the art, in such a configuration, a guide wire can extend
through the guide wire lumen, hub portion lumen 218 and hub lumen
228 for normal use. An inflation lumen in fluid communication with
port lumen 216 is defined within catheter tube 220 between guide
wire tube 226 and tube 220.
[0030] The hub and manifold assemblies of the present invention are
preferably integrally molded in one piece. The hub assembly is
preferably formed by insert molding. In this process, a mandrel is
inserted into the end of a catheter tube. A portion of the mandrel
preferably extends from the end of the catheter tube. The catheter
tube and mandrel are placed within the mold. Molten material is
injected into the mold around the end of the catheter and the
mandrel to form the integral hub assembly on the end of the
catheter tube. Other standard molding techniques as well known in
the art may be used to integrally mold the hub assembly of the
present invention.
[0031] Material such as PEBA (polyether block amide polymer,
commercially available under the trade name PEBAX), Isoplast or
other polyurethanes, nylon, polycarbonate, ULTEM, polyester
polycaprolactone, and high density polyethylene or similar material
may be used to form the hub and manifold assemblies of the present
invention. Depending upon the specific use of the hub assembly, the
flexural modulus of the material to be used is preferably between
60,000 and 500,000 psi. However, materials having a higher or lower
flexural modulus can be used depending upon the particular
application for the hub assembly. For example, materials having a
higher flexural modulus can be used with a relatively stiff
catheter tube whereas materials having a lower flexural modulus can
be used with relatively more flexible catheter tubes.
[0032] Numerous characteristics and advantages of the invention
covered by this document have been set forth in the foregoing
description. It will be understood, however, that this disclosure
is, in many respects, only illustrative. Changes may be made in
details, particularly in matters of shape, size, and arrangement of
parts without exceeding the scope of the invention. The invention's
scope is, of course, defined in the language in which the appended
claims are expressed.
* * * * *