U.S. patent application number 10/658748 was filed with the patent office on 2004-05-20 for stent delivery system with spacer member.
This patent application is currently assigned to ev3 Peripheral, Inc. Invention is credited to Thompson, Paul J..
Application Number | 20040097959 10/658748 |
Document ID | / |
Family ID | 25074303 |
Filed Date | 2004-05-20 |
United States Patent
Application |
20040097959 |
Kind Code |
A1 |
Thompson, Paul J. |
May 20, 2004 |
Stent delivery system with spacer member
Abstract
A stent delivery system includes outer and inner elongated,
flexible tubular members each having a distal and proximal ends.
The outer tubular member is sized to be passed through the body
lumen with the distal end advanced to the deployment site and with
the proximal end remaining external of the patient's body for
manipulation by an operator. The inner tubular member is sized to
be received within the outer tubular member. The outer tubular and
inner tubular members are axially slideable relative to one another
between a transport position and the deploy position. The inner
tubular member has a stent attachment location at its distal end.
The stent attachment location is covered by the outer tubular
member when the inner and outer tubular members are in the
transport position. The stent attachment location is exposed when
the inner and outer tubular members are in the deploy position. A
spacer member is disposed between the inner and outer tubular
members. The spacer member maintains spacing between the inner and
outer tubular members. Opposing surfaces of the inner and outer
tubular members define a first lumen extending from the proximal
end towards the distal end of the outer tubular member. An
admission port is provided in communication with the first lumen at
the proximal end of the outer tubular member. A discharge port is
formed through the outer tubular member in communication with the
first lumen at the distal end of the outer tubular member.
Inventors: |
Thompson, Paul J.; (New
Hope, MN) |
Correspondence
Address: |
Attention of David G. Schmaltz
MERCHANT & GOULD P.C.
P.O. Box 2903
Minneapolis
MN
55402-0903
US
|
Assignee: |
ev3 Peripheral, Inc
Plymouth
MN
|
Family ID: |
25074303 |
Appl. No.: |
10/658748 |
Filed: |
September 9, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10658748 |
Sep 9, 2003 |
|
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09765719 |
Jan 18, 2001 |
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6623491 |
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Current U.S.
Class: |
606/108 ;
604/104; 623/1.11 |
Current CPC
Class: |
A61F 2/95 20130101; A61M
25/0021 20130101; A61F 2/9517 20200501; A61F 2/966 20130101; A61M
25/0043 20130101; A61F 2/958 20130101 |
Class at
Publication: |
606/108 ;
623/001.11; 604/104 |
International
Class: |
A61F 011/00; A61F
002/06 |
Claims
What is claimed is:
1. A stent delivery system for delivering a stent to a deployment
site in a body lumen of a patient's body, said stent delivery
system comprising: an elongated, flexible, hollow outer tubular
member having a distal end and a proximal end; an elongated,
flexible, inner tubular member having a distal end and a proximal
end; said outer tubular member sized to be passed through said body
lumen with said distal end advanced to said deployment site and
with said proximal end external to said body for manipulation by an
operator; said inner tubular member sized to be received within
said outer tubular member with said inner tubular member and said
outer tubular member axially slideable relative to one another
between a transport position and a deploy position; said inner
tubular member having a stent attachment location at said distal
end of said inner tubular member, said stent attachment location
covered by said outer tubular member when said inner and outer
tubular members are in said transport position, said stent
attachment location exposed when said inner and outer tubular
members are in said deploy position; a spacer member disposed
between said inner tubular member and said outer tubular member
with said spacer member spacing said inner tubular member from said
outer tubular member; opposing surfaces of said inner and outer
tubular members defining a first lumen extending from said proximal
end towards said distal end of said outer tubular member; an
admission port in communication with said first lumen at proximal
end of said outer tubular member; and a discharge port through said
outer tubular member in communication with first said lumen at said
distal end of said outer tubular member.
2. A stent delivery system according to claim 1 wherein said spacer
member is a longitudinal spacer member extending substantially an
entire length from said proximal end of said outer tubular member
to said stent attachment location.
3. A stent delivery system according to claim 1 wherein said spacer
member is disposed to maintain said inner tubular member centrally
positioned within said outer tubular member.
4. A stent delivery system according to claim 1 wherein said spacer
member is a plurality of splines carried on said inner tubular
member and extending radially outwardly towards said outer tubular
member and extending linearly along a length of said inner tubular
member.
5. A stent delivery system according to claim 1 wherein said inner
tubular member is hollow to track over a guide wire.
6. A stent delivery system according to claim 1 further comprising
a stent carried at said stent attachment location.
7. A stent delivery system according to claim 1 further comprising
a first handle rotatably connected to said proximal end of said
outer tubular member.
8. A stent delivery system according to claim 1 further comprising
a second handle rotatably connected to said proximal end of said
inner tubular member.
9. A stent delivery system according to claim 1 comprising a
locking member for fixing a relative axial position between said
inner tubular member and said outer tubular member.
Description
I. BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] This invention pertains to a system for delivering a stent
to a site in a body lumen. More particularly, this invention
pertains to a stent delivery system with improved structure between
sliding tubular members.
[0003] 2. Description of the Prior Art
[0004] Stents are widely used for supporting a lumen structure in a
patient's body. For example, stents may be used to maintain patency
of a coronary artery, other blood vessel or other body lumen.
[0005] Commonly, stents are commonly metal, tubular structures.
Stents are passed through the body lumen in a collapsed state. At
the point of an obstruction or other deployment site in the body
lumen, the stent is expanded to an expanded diameter to support the
lumen at the deployment site.
[0006] In certain designs, stents are open-celled tubes which are
expanded by inflatable balloons at the deployment site. Other
stents are so-called "self-expanding" stents. Self-expanding stents
do not use balloons or other application of force to a collapsed
stent to cause the expansion of the stent. An example of a
self-expanding stent is a coil structure which is secured to a
stent delivery device under tension in a collapsed state. At the
deployment site, the coil is released so that the coil can expand
to its enlarged diameter. Other self-expanding stents are made of
so-called shape-memory metals such as nitinol. Such shape-memory
stents experience a phase change at the elevated temperature of the
human body. The phase change results in expansion from a collapsed
state to an enlarged state.
[0007] A delivery technique for shape-memory alloy stents is to
mount the collapsed stent on a distal end of a stent delivery
system. Such a system would include an outer tubular member and an
inner tubular member. The inner and outer tubular members are
axially slideable relative to one another. The stent (in the
collapsed state) is mounted surrounding the inner tubular member at
its distal end. The outer tubular member (also called the outer
sheath) surrounds the stent at the distal end.
[0008] Prior to advancing the stent delivery system through the
body lumen, a guide wire is first passed through the body lumen to
the deployment site. The inner tube of the delivery system is
hollow throughout its length such that it can be advanced over the
guide wire to the deployment site.
[0009] The combined structure (i.e., stent mounted on stent
delivery system) is passed through the patient's lumen until the
distal end of the delivery system arrives at the deployment site
within the body lumen. The deployment system may include
radio-opaque markers to permit a physician to visualize positioning
of the stent prior under fluoroscopy to deployment.
[0010] At the deployment site, the outer sheath is retracted to
expose the stent. The exposed stent is now free to expand within
the body lumen. Following expansion of the stent, the inner tube is
free to pass through the stent such that the delivery system can be
removed through the body lumen leaving the stent in place at the
deployment site.
[0011] Throughout the procedure, it may be desirable to inject a
contrast media (a liquid which can be visualized under
fluoroscopy). The contrast media is injected into the space defined
between opposing surfaces of the inner and outer tubes. The outer
tube has side ports extending through the sidewall of the outer
tube near its distal end. The contrast media is injected into the
body lumen through the side ports.
[0012] Prior art stent delivery systems use inner and outer tubes
of generally uniform diameters and circular cross-section
throughout their length. This design relies upon the dynamics of
fluid flow to retain spacing between the tubes.
[0013] In the event the outer diameter of the inner prior art tube
is substantially less than the inner diameter of the outer prior
art tube, the inner tube could bend relative to the outer tube such
that surfaces of the inner tube abut surfaces of the outer tube. As
a result, axial forces applied to advance the stent delivery system
could be stored in the bent inner tube. Such energy could be
suddenly released with sudden and undesired rapid advance or
retraction of the distal tip of the tubes when the inner tube
straighten. Also, contact between the surfaces of the inner and
outer tubes members can result in friction between the members
resisting relative moment between the tubes.
[0014] The likelihood of the sudden jumping phenomena could be
reduced by having the inner and outer tube diameters be as close as
possible. However, such close tolerances result in a very small
annular gap between the inner and outer tubes which results in
increased resistance to flow of contrast media between the inner
and outer tube.
[0015] Another flaw with prior devices is the absence of
comfortable grips to permit the user (such as an interventional
cardiologist or a radiologist) to comfortably manipulate the inner
tube relative to the outer tube and to readily visualize the
relative positioning between the inner tube and outer tubes in
their axial alignment.
[0016] It is an object of the present invention to provide improved
structures for a stent delivery system.
II. SUMMARY OF THE INVENTION
[0017] According to a preferred embodiment of the present
invention, a stent delivery system is disclosed for delivering a
stent to a deployment site in a body lumen of a patient. The stent
delivery system includes outer and inner elongated, flexible
tubular members each having a distal and proximal ends. The outer
tubular member is sized to be passed through the body lumen with
the distal end advanced to the deployment site and with the
proximal end remaining external of the patient's body for
manipulation by an operator. The inner tubular member is sized to
be received within the outer tubular member. The outer tubular and
inner tubular members are axially slideable relative to one another
between a transport position and the deploy position. The inner
tubular member has a stent attachment location at its distal end.
The stent attachment location is covered by the outer tubular
member when the inner and outer tubular members are in the
transport position. The stent attachment location is exposed when
the inner and outer tubular members are in the deploy position. A
spacer member is disposed between the inner and outer tubular
members. The spacer member maintains spacing between the inner and
outer tubular members. Opposing surfaces of the inner and outer
tubular members define a first lumen extending from the proximal
end towards the distal end of the outer tubular member. An
admission port is provided in communication with the first lumen at
the proximal end of the outer tubular member. A discharge port is
formed through the outer tubular member in communication with the
first lumen at the distal end of the outer tubular member.
III. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a side elevation view of a stent delivery system
according to the present invention;
[0019] FIG. 2 is a side sectional view of a distal end of the stent
delivery system of FIG. 1, shown in FIG. 1 as Detail A;
[0020] FIG. 3 is a side sectional view of a proximal end of the
stent delivery system of FIG. 1, shown in FIG. 1 as Detail B;
[0021] FIG. 4 is a sectional view of a second handle of the stent
delivery system of FIG. 1 and showing, in section, a guide wire
port, shown in FIG. 1 as Detail C;
[0022] FIG. 5 is a cross-sectional view of the inner and outer
tubular members of the stent delivery system of FIG. 1 taken along
lines 5-5 of FIG. 3;
[0023] FIG. 6 is a perspective view of one-half of a handle of the
stent delivery system of FIG. 1 with the opposite half being of
identical construction;
[0024] FIG. 7A is a perspective view of one of the handles of the
stent delivery system of FIG. 1;
[0025] FIG. 7B is a front end view of the handle of FIG. 7A;
[0026] FIG. 7C is a back end view of the handle of FIG. 7A;
[0027] FIG. 7D is a front side view of the handle of FIG. 7A;
[0028] FIG. 7E is a back side view of the handle of FIG. 7A;
[0029] FIG. 7F is a top view of the handle of FIG. 7A; and
[0030] FIG. 7G is a bottom view of the handle of FIG. 7A.
IV. DETAILED DESCRIPTION
[0031] With reference now to the various drawing figures in which
identical elements are numbered identically throughout, a
description of a preferred embodiment of the present invention will
now be provided.
[0032] With initial references to FIGS. 1-4, a stent delivery
system 10 is shown. The stent delivery system 10 is for delivery of
a stent 12 (schematically shown only in FIG. 2) to a deployment
site in a body lumen of a patient's body. By way of non-limiting,
representative example, the stent 12 may be a self-expanding,
open-celled, tubular stent having a construction such as that shown
in U.S. Pat. No. 6,132,461 and formed of a self-expanding,
shape-memory or superelastic metal such as nitinol, or the like.
The stent 12 may also be a coil stent or any other self-expanding
stent.
[0033] The stent 12 is carried on the stent delivery system 10 in a
collapsed (or reduced diameter) state. Upon release of the stent 12
from the stent delivery system 10 (as will be described), the stent
12 expands to an enlarged diameter to abut against the walls of the
patient's lumen in order to support patency of the lumen.
[0034] The stent delivery system 10 includes an inner tubular
member 14 and an outer tubular member 16. Both of the inner and
outer tubular members 14 and 16 extend from proximal ends 14a, 16a
to distal ends 14b, 16b.
[0035] The outer tubular member 16 is sized to be axially advanced
through the patient's body lumen for the distal end 16b to be
placed near the deployment site in the body lumen and with the
proximal end 16a remaining external to the patient's body for
manipulation by an operator. By way of example, the outer tubular
member 16 (also referred to as a sheath) may be a braid-reinforced
polyester of tubular construction to resist kinking and to transmit
axial forces along the length of the sheath 16. The outer tubular
member 16 may be of widely varying construction to permit varying
degrees of flexibility of the outer tubular member 16 along its
length.
[0036] The proximal end 16a of the outer tubular member 16 is
bonded to a manifold housing 20. The manifold housing 20 is
threadedly connected to a lock housing 22. A strain relief jacket
24 is connected to the manifold housing 20 and surrounds the outer
tubular member 16 to provide strain relief for the outer tubular
member 16.
[0037] The inner tubular member 14 is preferably formed of nylon
but may be constructed of any suitable material. Along a portion of
its length from the proximal end 16a of the, outer tubular member
16 to a stent attachment location 26 (shown in FIG. 2), the inner
tubular member 14 is a cylinder with a spacer member 18 which, in a
preferred embodiment, comprises radially projecting and axially
extending splines 18 (best shown with reference to FIGS. 3 and 5).
The function and purpose of the splines 18 will be described
later.
[0038] At the distal end 14b of the inner tubular member 14, the
inner tubular member 14 has no splines. The splineless length of
the distal end of the inner tubular member 14 is of sufficient
length to be greater than an axial length of the stent 12. This
distal splineless length of the inner tubular member defines the
stent attachment location 26 between spaced apart radio-opaque
markers 21, 28 which are attached to the inner tubular member 14.
The radio-opaque markers 27, 28 permit a physician to accurately
determine the position of the stent attachment location 26 within
the patient's lumen under fluoroscopy visualization. A tapered and
flexible distal tip member 30 is secured to the reduced and
splineless portion of the inner tubular member 14. The highly
flexible distal tip member 30 permits advancement of the stent
deployment system 10 through the patient's lumen and minimizes
trauma to the walls of the patient's lumen.
[0039] As best shown in FIGS. 3 and 4, from the proximal end 16a of
the outer tube 16 to the inner tube proximal end 14a, the inner
tube 14 is cylindrical and splineless. The inner tube 14 passes
through both the manifold housing 20 and lock housing 22. A
stainless steel jacket 32 surrounds and is bonded to the inner
tubular member 14 from the proximal end 14a up to and abutting the
splines 18.
[0040] At the inner tube proximal end 14a, a port housing 34 is
bonded to the stainless steel jacket 32. The port housing 34 has a
tapered bore 36 aligned with an inner lumen 38 of the tubular
member 14. The inner lumen 38 extends completely through the inner
tubular member 14 so that the entire delivery system 10 can be
passed over a guide wire (not shown) initially positioned within
the patient's lumen. Opposing surfaces of the inner and outer
tubular members 14 and 16, define a first lumen 40 (best seen in
FIG. 5).
[0041] The manifold housing 20 carries an admission port 42 for
injecting a contrast media into the interior of the manifold
housing 20. The interior of the manifold housing 20 is in fluid
flow communication with the first lumen 40. Discharge ports 41 are
formed through the outer tubular member 16 to permit contrast media
to flow from the first lumen 40 into the patient's body lumen.
[0042] An O-ring 44 surrounds the stainless steel jacket 32 between
the manifold housing 20 and lock housing 22. Upon threaded
connection of the manifold housing 20 to the lock housing 22, the
O-ring 44 compresses against the stainless steel jacket 32 in
sealing engagement to prevent contrast media from flowing in any
path other than through the first lumen 40.
[0043] The lock housing 22 carries a threaded locking member (or
lock nut) 46 which can be turned to abut the stainless steel jacket
32. The lock nut 46 can be released to free the stainless steel
jacket to move axially. According, when the lock nut 46 engages the
jacket 32, the jacket 32 (and attached inner tubular member 14)
cannot move relative to the lock housing 22, manifold housing 20 or
the outer tubular member 18. Upon release of the lock nut 46, the
inner tubular member 14 and outer tubular member 18 are free to
slide axially relative to one another between a transport position
and a deploy position.
[0044] First and second handles 48, 50 are secured to the lock
housing 22 and jacket 32, respectively. In the transport position,
the handles 48, 50 are spaced apart and the outer tubular member 18
covers the stent attachment location 26 to prevent premature
deployment of the stent 12. When the handle 48 is pulled rearwardly
toward the handle 50, the outer tubular member 16 slides rearwardly
or proximally relative to the inner tubular member 14. Preferably,
the outer tubular member 16 slides rearwardly a distance sufficient
to fully expose the stent attachment location 26 and permit the
stent 12 to freely expand toward its fully expanded diameter. After
such expansion, the stent delivery system can be proximally
withdrawn through the expanded stent and removed.
[0045] The first handle 48 is rotatably mounted on a flange 22a of
the lock housing 22. The first handle 48 surrounds the stainless
steel jacket 32 and is freely rotatable about the longitudinal axis
of the jacket 32 and freely rotatable about the flange 22a. The
first handle 48 is axially affixed to the lock housing 22 such that
axially forces applied to the first handle 48 are transmitted
through the lock housing 22 and manifold housing 20 to the outer
tubular member 16 to axially move the outer tubular 16. However,
rotary action of the first handle 48 about the axis of the
stainless steel jacket 32 is not transmitted to the housings 20, 22
or to the outer tubular member 16 by reason of the free rotation of
the first handle 48 on flange 22a.
[0046] The second handle 50 is mounted on an anchor 52 which is
bonded to the stainless steel jacket 32 through any suitable means
(such as by use of adhesives). The anchor 52 includes a flange 52a
which is radial to the axis of the stainless steel jacket 32. The
second handle 50 is mounted on the flange 52a and is free to rotate
on the anchor 52 about the axis of the stainless steel jacket 32.
However, axial forces applied to the handle 50 are transmitted to
the stainless steel jacket 32 which, being bonded to the inner
tubular member 14, results in axial movement of the inner tubular
member 14.
[0047] With the handle construction described above, relative axial
movement between the handles 48, 50 results in relative axial
movement between the inner and outer tubular members 14, 16.
Rotational movement of either of the handles 48, 50 does not affect
rotational positioning of the inner or outer tubular members 14, 16
and does not affect axial positioning of the inner and outer tubes
14, 16.
[0048] The free rotation of the handles 48, 50 results in ease of
use for a physician who may position his or her hands as desired
without fear of interfering with any axial positioning of the inner
and outer tubular members 14, 16. The spacing between the handles
48, 50 is equal to the stroke between the transport position and
the deploy position of the tubular members 14, 16. As a result, the
spacing permits the operator to have ready visual indication of the
relative axial positioning between the inner and outer tubular
members 14, 16. This relative axial positioning can be fixed by
engaging the lock nut 46. In any such positioning, contrast media
can be injected through the admission port 42 into the chamber 40
with the contrast media flowing out of the side ports 41 into the
body lumen to permit visualization under fluoroscopy.
[0049] With reference to FIG. 6, each of the handles 48, 50 is
formed of identical halves 49 (FIG. 6) of injected molded plastic
to permit ease of manufacture. When the handle halves 49 are joined
together, pins 64 are received in aligned openings 66 of an
opposing half 49 for attachment and permanent connection of two
halves 49. The halves 49 include first openings 60 proximate to the
outer diameter of the stainless steel jacket 32. At opposite ends,
the halves 49 include annular recesses 62 to receive either of
flanges 22a or 52a for rotatable attachment upon joinder of two
halves 49.
[0050] In the preferred embodiment shown, the splines 18 are
radially projecting and extend substantially the entire axial
length of the inner tubular member 14 between the proximal end 16b
of the outer tubular member 16 and the proximal radio-opaque marker
27. The radial dimension and axial length of each of the splines 18
is identical and, in a preferred embodiment, all splines 18 have a
continuous uninterrupted length. However, it will be appreciated
that the radial dimensions need not be identical and the splines 18
need not have an uninterrupted length. Instead, the splines 18 are
an example of an embodiment of a spacer member used to maintain a
spacing between the outer tubular member 16 and inner tubular
member 14.
[0051] The spacer member 18 keeps the inner tubular member 14 in
concentric alignment with the outer tubular member 16. This permits
the use of a very small diameter inner tubular member 14 relative
to the diameter of the outer tubular member 16 to increase the
volume of the first lumen 40. This reduces any impediment to flow
of contrast media through the first lumen 40 and increases the
volume of contrast media within the first lumen 40.
[0052] By reason of the splines 18, the inner tubular member 14
cannot bend relative to the outer tubular member 16 thereby
avoiding the problems associated with the prior art designs as
previously discussed. Also, since the splines 18 contact the outer
tubular member 16 only at small surface areas along the length,
very small friction results from sliding motion between the inner
and outer tubular members 14, 16.
[0053] With stent deployment systems having premounted stents of
various axial lengths, the positioning of the second handle 50 on
the stainless steel jacket 32 can be selected at time of assembly
so that a spacing S (see FIG. 1) between the handles 48, 50
corresponds to the length of the stent 12 carried on the stent
deployment system. For example, in a preferred embodiment, the
spacing S is about 10 millimeters longer than the deployed length
of the stent. Accordingly, the user will know that the outer
tubular member 16 has been fully retracted when the handles 48, 50
have been pushed completely together to completely release the
stent 12. Also, the freely rotatable handles 48, 50 are easy to
hold from any angle without slippage. The lock nut 46 ensures that
the stent 12 will not deploy prematurely.
[0054] FIGS. 7A-7G show one of the handles 48, 50 in isolation from
the delivery system 10. The depicted handle 48, 50 is elongated
along a central axis A-A and includes a first end 102 positioned
opposite from a second end 104. The first end 102 preferably has a
smaller perimeter (i.e., circumference) than the second end 104.
For example, as shown in FIG. 7D, the first end preferably has a
radial dimension d1 (i.e., the diameter of the first end 102) that
is smaller than a radial dimension d2 of the second end 104 (i.e.,
the diameter of the second end 104). Preferably, the ends 102 and
104 have a generally round perimeter.
[0055] Referring to FIGS. 7F and 7G, the handle 48, 50 also
includes first and second sides 106 and 108 that extend
longitudinally between the first and second ends 102 and 104. The
first and second sides 106 and 108 preferably face in opposite
directions. Concave gripping regions 110 and 112 are located at the
first and second sides 106 and 108. The concave gripping regions
110 and 112 each define a concave curvature as the gripping regions
110, 112 extend in a longitudinal direction (i.e., along axis A-A)
between the first and second ends 102 and 104.
[0056] Referring to FIGS. 7D and 7E, the handle 48, 50 also
includes third and fourth sides 114 and 116 that extend
longitudinally between the first and second ends 102 and 104. The
third and fourth sides 114 and 116 face in opposite directions, and
extend circumferentially (about the axis A-A) between the first and
second sides 106 and 106.
[0057] Preferably, the third and fourth sides 114 and 116 include
convex regions 118 that extend in a longitudinal direction along an
intermediate region of the handle 48, 50, and concave regions 121
and 123 that extend from the convex regions to the ends 102 and 104
of the handle 48, 50. The third and fourth sides 114 and 116 also
define a convex curvature that extends in a circumferential
direction (i.e., about the axis A-A as best shown in FIGS. 7B and
7C).
[0058] Referring again to FIGS. 7D and 7E, a length L of the
concave gripping regions 110, 1 12 is preferably shorter than a
total length of the handle 48, 50. Also, the gripping regions 110,
112 are preferably generally centered along the total length of the
handle 48, 50. Additionally, the regions 110, 112 preferably
include top and bottom edges 122 and 124 having convex curvatures
126 that transition into concave curvatures 128 adjacent the first
end 102. The regions 110, 112 preferably have a maximum transverse
width W at an intermediate position along their lengths L. The
width W is preferably measured in a direction transverse relative
to the axis A-A. The regions 110, 112 also preferably include
elongated gripping projections 130. The gripping projections 130
are preferably parallel to one another, and preferably extend in a
transverse direction relative to the axis A-A. The projections 130
are preferably longer at the intermediate positions of the gripping
regions 110, 112 than adjacent the ends of the gripping regions
110, 112. In one non-limiting embodiment, the main body of the
handle 48, 50 is made of a relatively hard material (e.g.,
polybutylene terephthalate) and the gripping regions 110, 112 are
made of a softer, more resilient material (e.g., an overmolded
polyester elastomer).
[0059] It has been shown how the objects of the invention have been
attained in a preferred manner. Modifications and equivalents of
the disclosed concepts are intended to be included within the scope
of the claims.
* * * * *