U.S. patent application number 14/454756 was filed with the patent office on 2014-11-27 for inverted stent cutting process.
The applicant listed for this patent is BOSTON SCIENTIFIC SCIMED INC.. Invention is credited to Kenneth M. Merdan, Matthew S. Shedlov.
Application Number | 20140346153 14/454756 |
Document ID | / |
Family ID | 34963153 |
Filed Date | 2014-11-27 |
United States Patent
Application |
20140346153 |
Kind Code |
A1 |
Merdan; Kenneth M. ; et
al. |
November 27, 2014 |
INVERTED STENT CUTTING PROCESS
Abstract
A stent manufacturing device and methods for making
intravascular stents and other medical devices. The stent
manufacturing device may include a base, a laser or other cutting
device coupled to the base, a horizontal motor coupled to the base,
and a rotary motor coupled to the horizontal motor. A workpiece can
be attached to the cutting device, for example adjacent the rotary
motor, and the workpiece can be cut with the cutting device.
Inventors: |
Merdan; Kenneth M.;
(Loretto, MN) ; Shedlov; Matthew S.; (St. Paul,
MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BOSTON SCIENTIFIC SCIMED INC. |
Maple Grove |
MN |
US |
|
|
Family ID: |
34963153 |
Appl. No.: |
14/454756 |
Filed: |
August 8, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10822883 |
Apr 13, 2004 |
8816244 |
|
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14454756 |
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Current U.S.
Class: |
219/121.67 |
Current CPC
Class: |
B23K 37/0461 20130101;
B23K 26/142 20151001; B23K 26/146 20151001; B23K 26/0823 20130101;
B23K 37/04 20130101; B23K 26/083 20130101; B23K 26/38 20130101 |
Class at
Publication: |
219/121.67 |
International
Class: |
B23K 26/38 20060101
B23K026/38; B23K 26/14 20060101 B23K026/14; B23K 26/08 20060101
B23K026/08 |
Claims
1. A device for manufacturing an intravascular stent, comprising: a
base having a first surface and a second surface; a laser cutting
system attached to the first surface; a linear motor attached to
the second surface; and a rotary motor coupled to the linear motor.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 10/822,883, filed Apr. 13, 2004.
FIELD OF THE INVENTION
[0002] The present invention pertains to intravascular stents and
other tubular medical devices. More particularly, the present
invention pertains to methods and device for manufacturing stents
and other tubular medical devices.
BACKGROUND OF THE INVENTION
[0003] A wide variety of stents have been developed. In addition, a
wide variety of devices and methods for manufacturing stents and
other medical devices have been developed. Among these known
devices and methods, each has certain advantages and disadvantages.
There is an ongoing need to provide alternative devices and methods
for making stents and other medical devices.
SUMMARY OF THE INVENTION
[0004] The invention provides design, material, and manufacturing
method alternatives for stents and medical device manufacturing
devices. In at least some embodiments, a stent manufacturing device
may include a base, a laser or other cutting device coupled to the
base, a horizontal motor coupled to the base, and a rotary motor
coupled to the horizontal motor. A workpiece can be attached to the
cutting device, for example adjacent the rotary motor, and the
workpiece can be cut with the cutting device. These and some of the
other features and characteristics of example embodiments are
described in more detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a side view of an example stent cutting
device;
[0006] FIG. 2 is a side view of another example stent cutting
device; and
[0007] FIG. 3 is a front view of the stent cutting device shown in
FIG. 2.
DETAILED DESCRIPTION
[0008] The following description should be read with reference to
the drawings wherein like reference numerals indicate like elements
throughout the several views. The detailed description and drawings
illustrate example embodiments of the claimed invention.
[0009] FIG. 1 is a side view of an example stent cutting device 10
that is similar to those typically used and known in the art.
Cutting device 10 includes a laser 12 attached to a first base 14.
A tubular workpiece 16 is positioned below laser 12 and is attached
to a linear motor 18 and a rotary motor 20. Linear motor 18 and/or
rotary motor 20 are attached to a second base 22 that is separate
from first base 14. In some embodiments, linear motor 18 and/or
rotary motor 20 are direct-drive motors that directly manipulate
workpiece 16. In other embodiments, linear motor 18 and/or rotary
motor 20 may indirectly move workpiece 16, for example, through the
use of a drive belt or other device. Second base 22 is positioned
below laser 12 and generally below first base 14. To cut a stent,
laser energy LE is transmitted from laser 12 onto workpiece 16
(e.g., directly onto workpiece 16 or reflected onto workpiece 16 by
a tuning mirror 42 or series of tuning mirrors 42) so that a number
of cuts can be made in workpiece 16. The shape and pattern of the
cuts can be manipulated by longitudinally moving workpiece 16 with
linear motor 18 (as indicated by the left/right arrow adjacent
linear motor 18) and/or rotating workpiece 16 with rotary motor 20
(as indicated by the rotary arrow adjacent rotary motor 20). A
fluid media 36 may be passed through or onto workpiece 20 during
the cutting procedure for the purposes of washing away debris
generated by cutting, cooling, and to prevent laser 12 from cutting
through both walls of the tubular workpiece 16.
[0010] Because of the minute size of stents and the cut patterns
within the stents, it can be appreciated that great precision is
required when using cutting device 10. For example, the orientation
of laser 12 (and one or more tuning mirrors 42) relative to
workpiece 16 must be precisely aligned. Moreover, movement of
workpiece 16 with linear motor 18, rotary motor 20, or other motion
devices requires precise and accurate movement. Because of this,
linear motor 18 and rotary motor 20 are highly tuned and highly
aligned so as to provide the level of precision and accuracy called
for. This level of precision generally causes devices like device
10 to be expensive due to the cost of purchasing (or building) and
maintaining these machines.
[0011] As it can be seen in FIG. 1, linear motor 18 and rotary
motor 20 are generally positioned below workpiece 16 and/or laser
12. Accordingly, it may be possible (or even probable) that fluid
media 36 that is passed onto or through workpiece 16, debris
generated by cutting workpiece 16, or both may have a tendency to
come into contact with linear motor 18 and/or rotary motor 20.
Because of the level of precision required by motors 18/20 and
because of the probably that fluid 36 and/or cutting debris may
become disposed on these motors 18/20, regular maintenance and
cleaning of motors 18/20 may be required in order to achieve
optimal performance. This is because fluid media 36 and debris may
be corrosive or otherwise damaging to the sensitive motors 18/20
(which may include electrical mechanisms, bearings, and the like).
It can be appreciated that this maintenance can be costly and time
consuming. In addition, the maintenance procedures themselves may
damage these precise motors 18/20 or otherwise decrease the
expected life of these motors 18/20.
[0012] In order to overcome some of these maintenance and other
issues, a number of alternative stent cutting devices and
procedures have been developed. One such alternative device was
disclosed in U.S. patent application Ser. No. 10/190,975, the
entire disclosure of which is hereby incorporated by reference.
This stent cutting device utilizes a vertical orientation where the
laser, motors, and workpiece are arranged vertically.
[0013] Another alternative stent cutting device 110 is shown in
FIG. 2. It should be noted that although cutting device 110 is
described as being used for cutting stents, this is not intended to
be limiting. For example, cutting device 110 can be used to cut or
otherwise manufacture other devices such as snares, strain reliefs,
guidewire and catheter components, intravascular filtering devices
(including embolic protection and vena cava filters), and the like,
or any other suitable device.
[0014] Cutting device 110 utilizes a configuration where linear
motor 118 and/or rotary motor 120 (which are typically similar to
motors 18/20) are attached to a common base 124 along with a laser
or other cutting means 112. Workpiece 16 is coupled to rotary motor
120 and generally positioned below laser 112, linear motor 118, and
rotary motor 120. Accordingly, gravity will tend to pull fluid and
debris spray 136 downward and away from motors 118/120. This will
tend to reduce the maintenance required to sustain the precision
required by motors 118/120. Moreover, a number of wires or other
connections (not shown) between the various components may also be
positioned near motors 118/120 and away from fluid and debris spray
136. Thus, other components of cutting device 110 may be protected
by this configuration.
[0015] It can also be seen in FIG. 2 that linear motor 118 is
mounted onto or otherwise coupled to common base 124 in a manner
that can be described as being "up-side down". This is because the
surface of linear motor 118 that is generally considered to be its
top surface 126 is pointed downward or generally oriented in the
downward direction. The bottom surface 128 of linear motor 118 is
pointed up or otherwise oriented in the upward direction. Moreover,
bottom surface 128 of linear motor 118 is coupled to a downward
facing surface 130 of common base 124. Collectively, the
arrangement or spatial relationship of linear motor 118 and common
base 124 define the up-side down configuration of linear motor 118.
The up-side down configuration is different from the typical
"right-side up" arrangement utilized in typical stent cutting
devices, for example, like cutting device 10. Additionally, because
rotary motor 120 is attached or otherwise coupled to linear motor
118, rotary motor 120 can also be seen to be in an up-side down
configuration. It should be noted that switching the position of
linear motor 118 and rotary motor 120 (i.e., so that rotary motor
120 is attached to common base 124 and linear motor is coupled to
rotary motor 120) is also contemplated so that some embodiments
utilize this alternative configuration. For example, linear motor
118 and/or rotary motor 120 may be attached to any region of base
124 including along the legs 148a/b (best seen in FIG. 3) of base
124.
[0016] In addition to having gravity aid in keeping fluid and other
debris 136 away from the various components of cutting device 110,
being in the up-side down configuration and having motors 118/120
and laser 112 coupled to a singular common base 124 may provide
cutting device 110 with a number of other desirable
characteristics. For example, having the motion components (e.g.,
motors 118/120) and the optical or cutting components (e.g., laser
112) connected through common base 124 rather than a set of bases
or frames can reduce the relative motion that can be caused by
vibration, inertial forces, and thermal expansion (i.e., differing
amounts of thermal expansion attributed to differing materials).
Thus, the relative displacement of the various components relative
to one another can be reduced. This can aid in the ability to
maintain the precision utilized in a stent cutting procedure.
[0017] In addition, the up-side down configuration and the use of
common base 124 may also improve the layout of the various
components of cutting device 110 so that it may be easier to
access, service, clean, and maintain device 110. Moreover, common
base 124 may be spread out or "open". Because of the "openness" of
common base 124 and/or the up-side down configuration, which can be
seen in FIG. 3, device 110 may be generally more functionally
oriented so that automated part handling can be incorporated easier
into cutting device 110. For example, the configuration of cutting
device 110 improves fluid collection and debris reclamation. This
feature may be important when workpiece 16 includes platinum or
another material that would be desirable to recollect. In addition,
cutting device 110 is set up for the incorporation of additional
components and automated versions of the currently utilized
components.
[0018] Some of the additional components that may be used with
cutting device 110 may include a interface plate 134 and/or a
manually adjustable alignment stage 132 that may be disposed
adjacent linear motor 118. Stage 132 may be of the dovetail slide
type (available from Gilman Manufacturing) or may be or include a
controlled motor. In some embodiments, interface plate 134 and/or
stage 132 are integral components of linear motor 118 and may serve
as the bottom surface 128 of linear motor 118 itself.
Alternatively, interface plate 134 and/or stage 132 may be
positioned laterally or in any other suitable location relative to
linear motor 118 so that bottom surface 128 of linear motor 118 can
be attached to common base 124. The exact form of interface plate
134 and stage 132 may vary. For example, stage 132 could
alternatively be a linear motor. Linear motor 118 may also include
a base portion 118a and a carriage portion 118b. Base portion 118a,
generally, remains stationary. Carriage portion 118b may be
slidable along base portion 118a. Other components may include a
fluid and debris recapture device (not shown) that may be
positioned below workpiece 16 and that can be used to collect fluid
and debris spray that may be generated during the cutting
procedure. This recapture device may be used for selective material
removal.
[0019] As described above, it may be desirable to spray a fluid
(indicated in part by reference number 136) onto and/or through
workpiece 16 during the cutting procedure. The source of the fluid
spray may include a nozzle (not shown) positioned adjacent
workpiece 16 that is configured to spray the fluid 136 onto or
through workpiece 16. According to this embodiment, the nozzle may
be attached to rotary motor 120, common base 124, another
peripheral base member, or at any other suitable location.
Alternatively, the fluid source may piped in through the tubular
workpiece 16 by connecting a fluid conduit to workpiece 16 or
simply passing fluid 136 into workpiece 16 by directly connecting
workpiece to a fluid source. It can be appreciated that a number of
differing fluid sources may be utilized without departing from the
spirit of the invention.
[0020] Fluid 136 may serve a number of purposes during the cutting
procedure. For example, fluid 136 may be useful for washing away
debris that is generated during the cutting procedure. In addition,
fluid 136 may also be used for cooling any heat that might be
generated during the cutting procedure. In some embodiments, fluid
136 may also act as a lubricant, oxidizer, cleaner, polishing
agent, pretreatment, and the like, or any other suitable purpose.
Accordingly, fluid 136 may comprise a number of different
materials. For example, fluid 136 may be water. Alternatively,
fluid 136 may be PRIMECUT.TM., CITRISURF.TM. (available from
Stellar Sollutions), other fluids, a gas, combinations thereof, or
any other suitable material.
[0021] One or more guides or bushings 138a/b may be connected to or
otherwise coupled to base 124. Guides 138a/b may be another base or
any other component of cutting device 110. Generally, guides 138a/b
can be used to assist in the holding and maintaining the position
of workpiece 16 relative to laser 112 and the other components of
cutting device 110. In some embodiments, workpiece 16 may be
longitudinally movable (via linear motor 118) between pre-cut guide
138a and post-cut guide 138b. By utilizing both a pre-cut guide
138a and a post-cut guide 138b, the precise position of workpiece
16 can be improved, which can improve the overall precision of the
cutting procedure. Guides 138a/b may also be attached to a number
of other portions of cutting device 110 such as base portion 118a
of linear motor 118, interface plate 134, or other (generally
stationary) components of device 110.
[0022] Common base 124 may be generally made from a relatively
massive or otherwise solid material. One example material that may
be utilized for common base 124 may be granite or another igneous
rock. Alternatively, common base 124 may be made from or otherwise
include a metal or metal alloy, a cast polymer, a structural metal,
a filled structural metal, and the like, or any other suitable
material. Common base 124 may be a singular piece of any other
these materials or it may be made from multiple pieces that are
attached together. Common base 124 may be arranged in an up-side
down "U" shape or otherwise have a horizontal component 146 and two
vertical legs 148a/b as shown in FIG. 3. This arrangement may
provide cutting device 110 with the "openness" that may be
desirable for some of the reasons stated above. Common base 124,
however, is not intended to be limited to this particular shape as
any suitable shape may be used. For example, common base 124 may
include only one vertical leg 148a so as to have an up-side down
"L" shape.
[0023] The motors 118/120 used in cutting device 110 may generally
include motors capable of repetitively producing the required level
of precision, accuracy, and repeatability for stent cutting
procedures. Linear motor 118 may generally include a longitudinally
moveable shaft and mechanical means for moving the shaft.
Longitudinal movement is indicated in FIG. 2 by the left/right
arrow. Examples of suitable linear motors 118 are the ALS Series
motors, which are commercially available from Aerotech. Rotary
motor 120 may generally include a rotary shaft and mechanical means
for moving the shaft. Rotary movement is indicated in FIG. 2 by the
rotary arrow. Examples of suitable rotary motors 120 are the ASR or
ADRT Series motors, which are commercially available from
Aerotech.
[0024] As suggested above, the cutting means 112 may generally
include a laser. Laser 112 is mounted or otherwise attached to
common base 124. The position of laser 112 on base 124 may vary.
For example, laser 112 may be mounted onto a top or upward facing
surface 140 of common base 124. However, this need not be the case
for all embodiments as laser 112 can be attached at essentially any
suitable location along base 112. In some embodiments, laser 112 is
configured to transmit laser energy LE downward onto workpiece 16.
This may be accomplished by disposing laser 112 directly over
workpiece 16 so that laser energy LE can be directly transmitted
onto workpiece 16. Alternatively, laser 112 may transmit laser
energy LE in a different direction (e.g., laterally) and then the
laser energy LE can be reflected or otherwise directed onto
workpiece 16 by one or more tuning mirrors 142 and through a beam
delivery or manipulating structure 144. The direction of the laser
energy LE is indicated by arrows. It can be appreciated that a
number of different configurations may be utilized without
departing from the spirit of the invention.
[0025] Laser 112 may generally comprise any one of a number of
known lasers such as YAG, diode, IR, UV, CO.sub.2, and the like, or
any other suitable laser or laser-like device. Alternatively, laser
112 may comprise a hybrid laser/water jet. An example of such a
laser/water jet hybrid is commercially available from SYNOVA Inc.,
of Lausanne, Switzerland and is described in PCT Publication No. WO
9532834 entitled Device For Machining Material With A Laser and the
corresponding U.S. Pat. No. 5,902,499, the entire disclosures of
which are herein incorporated by reference.
[0026] Workpiece 16 may generally be a tubular structure that, when
cut by cutting device 110, can form a stent or other medical
device. It should be noted that although the focus of this
description has been centered on forming intravascular stents, this
is not intended to be limiting as other devices may be formed using
the described devices and procedures. For example, cutting device
110 may be used to form grafts, stent-grafts, filters, cut or
notched tubes for catheters and other similar devices, other
devices for use within the body, and the like, or any other
suitable device. Moreover, workpiece 16 need not be tubular. For
example, workpiece 16 could be planar or form any suitable
three-dimensional structure.
[0027] Workpiece 16 may vary in size (i.e., length, outer diameter,
thickness, etc.), shape, and material composition. For example,
workpiece 16 may be made from any suitable materials such as
metals, metal alloys, polymers, metal-polymer composites, and the
like. Some examples of metals and metal alloys that may be used
include stainless steel, such as 304 V, 304 L, and 316 LV stainless
steel; mild steel; nickel-titanium alloy such as linear-elastic or
super-elastic nitinol, nickel-chromium alloy, nickel-chromium-iron
alloy, cobalt alloy, tungsten or tungsten alloys, MP35-N (having a
composition of about 35% Ni, 35% Co, 20% Cr, 9.75% Mo, a maximum 1%
Fe, a maximum 1% Ti, a maximum 0.25% C, a maximum 0.15% Mn, and a
maximum 0.15% Si), hastelloy, monel 400, inconel 825, or the like;
other Co--Cr alloys; platinum enriched stainless steel; or other
suitable material. In embodiments where the resultant medical
device is a stent, it may be desirable for workpiece 16 to be made
from or otherwise include a radiopaque material. Radiopaque
materials are understood to be materials capable of producing a
relatively bright image on a fluoroscopy screen or another imaging
technique during a medical procedure. This relatively bright image
aids the user of the medical device in determining its location.
Some examples of radiopaque materials can include, but are not
limited to, gold, platinum, palladium, tantalum, tungsten alloy,
plastic material loaded with a radiopaque filler, and the like.
[0028] Some examples of suitable polymers may include
polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene
(ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene
(POM), polybutylene terephthalate (PBT), polyether block ester,
polyurethane, polypropylene (PP), polyvinylchloride (PVC),
polyether-ester (for example a polyether-ester elastomer such as
ARNITEL.RTM. available from DSM Engineering Plastics), polyester
(for example a polyester elastomer such as HYTREL.RTM. available
from DuPont), polyamide (for example, DURETHAN.RTM. available from
Bayer or CRISTAMID.RTM. available from Elf Atochem), elastomeric
polyamides, block polyamide/ethers, polyether block amide (PEBA,
for example available under the trade name PEBAX.RTM.), silicones,
polyethylene (PE), Marlex high-density polyethylene, Marlex
low-density polyethylene, linear low density polyethylene (for
example REXELL.RTM.), polyethylene terephthalate (PET),
polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI),
polyphenylene sulfide (PPS), polyphenylene oxide (PPO),
polysulfone, nylon, perfluoro(propyl vinyl ether) (PFA), other
suitable materials, or mixtures, combinations, copolymers thereof,
polymer/metal composites, and the like. In some embodiments
workpiece 16 can be blended with a liquid crystal polymer (LCP).
For example, the mixture can contain up to about 5% LCP. In some
embodiments, a coating, for example a lubricious, a hydrophilic, a
protective, pharmacological, or other type of coating may be
applied over portions or all of workpiece 16, or other portions of
workpiece 16.
[0029] The cutting procedure may include connecting workpiece 16 to
cutting device 110 (i.e., connecting workpiece 16 to rotary motor
120, guides 138, or any other component of cutting device 110),
orienting workpiece 16 under laser 112, and directing laser energy
LE onto workpiece 16. Linear and rotary motors 118/120 can be used
to longitudinally move and rotate workpiece 16 during the cutting
process so that laser 112 can cut and impart the desired cutting
pattern onto workpiece 16. Additionally, fluid 136 may be sprayed
onto and/or through workpiece 16 to wash away debris or serve the
other purposes described above. Once the desired cutting pattern
has been imparted, the newly formed device can be separated from
workpiece 16 (that is, if the newly formed device is to be smaller
or shorter than workpiece 16) by simply cutting off the newly
formed device with laser 112 or any other suitable cutting
means.
[0030] It should be understood that this disclosure is, in many
respects, only illustrative. Changes may be made in details,
particularly in matters of shape, size, and arrangement of steps
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.
* * * * *