Apparatus for producing hollow ground needles

An apparatus for applying a cutting edge on surgical needles having at least one abrading device and a needle holding mechanism. The abrading device includes an abrasive member such as a rotatable abrasive belt or grinding wheel. The needle holding mechanism is positionable for selectively engaging an end of at least one needle with the abrading device to provide a cutting edge on the needle. A grinding wheel may be provided for hollow grinding the surgical needles, the grinding wheel including a cylindrical member having a plurality of ridges. The cylindrical member preferably has a super-abrasive coating of diamond or boron nitride particles electroplated thereon.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to devices for grinding surgical needles, and 
more particularly to devices, including grinding wheels, for abrading the 
needle to provide a surgical cutting edge on the needle through the use of 
an abrasive surface for grinding and/or polishing a needle, or a 
multiplicity of needles, simultaneously. The present invention 
additionally relates to an apparatus and a grinding wheel for producing 
hollow ground surgical needles. 
2. Description of the Related Art 
Surgical needle manufacture is a precise and time consuming procedure, 
particularly where individual needles are formed one at a time. 
Conventional surgical needle manufacturing typically begins with the step 
of cutting round wire stock to a predetermined length to form a needle 
blank. One end of the blank is then tapered to provide a point thereon. In 
some instances, such as for example in plastic surgery needles or taper 
cutting edge needles, a cutting edge must be formed at or near the point 
of the needle. To provide a cutting edge, the tapered end of the needle is 
stamped or pressed and then subjected to grinding and/or polishing to 
sharpen its longitudinal edges. Normally, at least a portion of the needle 
blank is pressed to provide flat surfaces on a portion of the needle to 
facilitate grinding. After the cutting edge is formed on the needle, the 
needle blank is cut to its final desired length and then prepared for 
suture attachment. The needle may be further subjected to additional steps 
such as polishing or hardening. 
Conventional needle processing is in large part a manual operation. 
Providing a cutting edge, for example, typically includes the steps of: 
grasping and holding a needle using a hand held device; manually moving 
the needle into contact with a rotating abrasive belt or grinding wheel; 
visually evaluating and/or confirming the progress of needle cutting edge 
formation; and repeating the steps of manually contacting the needle with 
the abrasive surface and visually checking the progress of the cutting 
edge formation for each edge to be applied to the needle. Since visual 
confirmation of a specified cutting edge in the view of the person 
performing the operation is required, the reproducibility, accuracy and 
hence quality of the cutting edge is largely a function of the skill and 
experience of the operator. 
More specifically, in the prior art the needle may be held by a pliers-like 
device or a chuck which grips an end of the needle opposite from the end 
of the needle where the cutting edge is to be applied. Usually, no more 
than two needles can be held in the device at one time, and the 
pliers-like device or chuck is used to manually engage the needle end with 
a rotating abrasive belt or wheel. The end of the needle is maintained in 
contact with the abrasive belt or wheel until the desired cutting edge is 
fashioned. 
Grinding wheels used in previously known methods are typically of the 
bonded type and generally require frequent redressing. During use, the 
abrasive grains on bonded grinding wheels become slightly dulled. Normal 
stresses in the grinding operation tear the worn grain from the wheel to 
expose a new cutting grain. A soft wheel wears too fast, losing grains 
before they are dulled, whereas too hard a wheel develops a smooth glazed 
surface which does not cut properly. As the abrasive wears, the 
configuration of the wheel surface changes enough to affect the grind on 
the finished product. When this occurs the wheel must then be re-dressed 
to open new abrasive grain surfaces or to recondition the grinding 
surface. The re-dressing is performed manually and may vary from operator 
to operator. Even slight variances may cause needle geometries to depart 
from the strict specifications, thereby resulting in a higher percentage 
of rejected parts and concomitant higher costs. 
Needle sharpness, both of its point and cutting edges, is an important 
factor during many surgical procedures. The surgeon's ability to perform 
delicate suturing operations is severely limited by needles with points 
and edges which are not sharp or which do not remain sharp. While flat 
pressing facilitates the formation of a needle edge, there is yet need of 
a way to increase and maintain the sharpness to which the cutting edge of 
a needle can be ground. 
One disadvantage to conventional needle abrading devices is that manually 
positioning needles for abrading can be irregular and inefficient. 
Additionally, the engagement and extent of the needle processing is 
visually monitored which can result in an inconsistent needle cutting 
edge. Another disadvantage of the conventional methods is the reliance on 
visual affirmation of the needle cutting edge which can be ineffective for 
meeting precise surgical needle specifications. Finally, the prior art 
devices provide for substantially little or no automation so that the 
process is time consuming. 
The novel device for applying a cutting edge to a surgical needle obviates 
the disadvantages encountered in the prior art and provides a device for 
automatically processing a plurality of needles at the same time. The 
device provides consistent and reproducible results, particularly with 
respect to needle geometry and surface finish, which ensures precision and 
accuracy in the application of cutting edges to needles during large scale 
manufacture. The device provides for both grinding the cutting edges onto 
the needle, as well as polishing and deburring to produce the finished 
product. The device also permits the application of cutting edges on 
several sides of the surgical needle without necessitating the removal and 
repositioning of the needles in the device to result in a precision 
multi-sided cutting edge surgical needle. 
SUMMARY OF THE INVENTION 
An apparatus for applying a cutting edge to surgical needles is provided 
which includes a frame for mounting at least one device for abrading the 
needles and a needle holding mechanism for securing the needles and moving 
the needles into engagement with the abrading device. The abrading device 
and the needle holding mechanism are positioned on the frame such that 
needles can be processed in an automated and efficient manner. The needle 
holding mechanism may hold a plurality of needle blanks to simultaneously 
engage the blanks with the abrading devices to provide a substantially 
identical cutting edge on each of the blanks. It is further contemplated 
that the needle holding mechanism is capable of rotating the needles to 
consecutively engage various sides of the needle to provide a multi-sided 
cutting edge. 
The abrading device preferably comprises a motor driven rotatable abrasive 
member, which rotates the abrasive member at a predetermined speed. The 
needle holding mechanism is movably mounted to the frame and is 
selectively positionable in relation to the abrading device. Preferably, 
the apparatus may provide a plurality of needle abrading devices 
positioned on the frame, each including at least one rotatable abrasive 
belt or wheel. 
The needle holding mechanism selectively engages the needles with the 
abrasive belts at each of the needle abrading devices. The holding 
mechanism moves the needles into and out of engagement with the abrasive 
belts or wheels of the abrading devices. The needle holding mechanism 
transports the needles to a position substantially perpendicular to each 
abrading device. 
The needles are engagable with the abrasive belt or wheel of each of the 
abrading devices at predeterminable selectable time intervals. The motion 
of the needle holding mechanism is hydraulically activated in conjunction 
with a programmable logic controller which automates the entire process. 
Hydraulic cylinders move the needles in the needle holding mechanism 
toward and away from the belt or wheel at each abrading device to engage 
an end of each needle with the belt or wheel. Hydraulic cylinders also 
move the needle holding mechanism to move the needles along an axis 
parallel to the abrading devices so that the needles can be positioned 
adjacent to each abrasive belt or wheel to be engaged with that belt. 
In a second embodiment an angled plate and track are provided in the needle 
holding mechanism to enable the mechanism to provide a compound motion to 
the needles as they engage the abrading devices. Preferably, the plate is 
oriented at an angle relative to the longitudinal axis of the needles. 
Hydraulic cylinders also move the needle holding mechanism along the 
angled plate to provide an up and down movement which can be synchronized 
with the inward and outward movement to provide a multi-axis compound 
movement of the needle holding mechanism relative to the abrading devices. 
Additionally, a method and apparatus are provided herein for "hollow 
grinding" needle blanks. The apparatus includes a generally cylindrical 
grinding wheel having a plurality of precisely spaced apart 
circumferential grinding ridges. The abrasive surface of the grinding 
wheels preferably comprises an electroplated superabrasive material such 
as diamond or boron nitride. In a method for hollowing grinding, elongated 
needle blanks, preferably having a triangular cross section and three flat 
sides, are placed in a holder and contacted against the rotating grinding 
wheel to produce a concave depression oriented along the length of the 
needle blank. A needle blank can thus be formed with three hollowed sides. 
The needle blanks may be tapered by grinding to a sharp point and may 
subsequently be polished and bent into a curved configuration.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring to the drawings, in which like reference numerals identify 
identical or similar elements, there is illustrated a preferred embodiment 
of an apparatus 10 for applying a cutting edge to surgical needles. 
Apparatus 10 processes stock needle blanks, such as blank 12, 12' shown in 
FIGS. 7A and 7B, respectively, or a pre-tapered blank 14 as shown in FIG. 
8. A portion of the needle blank may be coined or flat pressed to impart a 
desired cross-sectional shape to the needle blank prior to processing by 
apparatus 10. Apparatus 10 applies at least one cutting edge 16 on blank 
12, and in a preferred embodiment, three edges 16 are applied as seen in 
FIGS. 9 and 10. 
Referring to Figs. I and 2, the apparatus 10 includes a frame or table 18 
having a working surface 20. The apparatus 10 comprises a series of 
abrading stations 22 positioned on the work surface 20 for abrading a 
multiplicity of needles to apply cutting edges thereon. The abrading 
stations 22 refine the needle blank 12 in sequential stages using rotating 
abrasive devices such as grinding belts or grinding stones and wheels. 
Each abrading device of the station 22 preferably represents a 
predetermined stage of needle refinement. 
The present invention processes a needle blank 12 to result in three 
cutting edges 16 utilizing three separate abrading devices 24, 26 and 28. 
Alternative embodiments, however, may have more or less than three 
abrading devices, and further may provide cutting edges on more or less 
than three sides. 
As best seen in FIGS. 1 and 3-5, the first abrading device 24 includes a 
first rotatable abrasive belt 30 rotated at a desirable speed by a motor 
32. The first abrasive belt 30 fashions a cutting edge on a needle by 
grinding an end of the needle blank 12. The first belt 30 has an 
abrasiveness for grinding an initial cutting edge on the end of a needle 
blank 12. 
A second abrading device 26 is positioned laterally adjacent and along a 
common axis with the first abrading device 24. The second abrading device 
26 includes a second rotatable abrasive belt 34 for further abrading blank 
12 to apply the cutting edge on the needle blank 12. 
The second belt 34 can also be rotated by motor 28. Preferably, however, 
another motor is used to rotate second belt 34 to allow a different 
grinding speed in connection with second belt 34. Different grinding 
speeds may be desirable for belts containing different abrasives, 
depending on factors such as abrasive composition or grit size. The second 
abrasive belt 34, preferably, is less abrasive than the first belt 30 to 
further refine the cutting edge after engagement with the first abrasive 
belt 30. In another embodiment, it is also contemplated that the second 
abrasive belt 34 could be equally or more abrasive than the first belt. 
A third abrading device 28 is positioned laterally adjacent to and along a 
common axis with the first two abrading devices 24 and 26. The third 
abrading device 28 includes a third rotatable abrasive belt 36 rotated by 
motor 38 at a predetermined speed. Preferably, the abrasiveness of the 
third belt 36 is less than the abrasiveness of the second abrasive belt 
34, and is particularly adapted for polishing the needle cutting edge 16 
to deburr the edge applied by the first two abrading devices 24 and 26. 
The third belt 36 may comprise a velvet flock belt to provide for 
deburring and polishing. However, deburring may also be accomplished by 
reversing the direction of third belt 36. Also, the speed of the motor 38 
may be adjusted for optimum polishing of the cutting edge. 
As seen in FIG. 1, the angle of the belts in relation to the needle blanks 
may be varied by adjusting the height of the abrading devices 24, 26 and 
28 utilizing adjusting rods 40. In addition, as best seen in FIGS. 3-5, 
the distance between the belts and the rest position of the needle clamp 
46 may be regulated by adjusting knobs 42 to advance or retract the belts. 
In an alternative embodiment the tension on the belts may be adjusted 
using mechanism 103 shown in FIG. 11. 
The abrasive belt at each of the abrading devices 24, 26 and 28 each 
preferably have an abrasiveness having micron values of between about 0.3 
microns to about 100 microns. While abrasive belts are preferred, it is 
also contemplated that abrasive wheels and grinding wheels may also be 
employed. 
While the preferred embodiment utilizes three abrading devices, it is also 
contemplated that an alternative apparatus may include any number of 
abrading devices for fashioning a cutting edge on a needle blank instead 
of a series of processing stations. The envisioned alternative apparatus 
may include a variable speed motor for rotating an abrasive belt at 
different speeds. Further, a series of belts can be interchangeably fitted 
on a rotating structure to provide various abrasive surfaces. 
Referring now to FIG. 2, a needle holding mechanism 44 is shown which 
includes a needle clamp 46 dimensioned and configured to hold at least one 
needle blank 12, or a multiplicity of needles 12 as shown. The needles 12 
are releasably held in the clamp 46, which may be disengaged as seen in 
FIG. 6 to remove the needles 12 from the clamp 46. This is accomplished by 
moving lever 48 upwardly to open the jaws 50 of the needle clamp 46. 
The needle holding mechanism 44 comprises an upper rod carriage 52 having a 
mounting block 54 for positioning the needle clamp 46 thereon. The 
mounting block 54 is slidably positioned on upper rods 56 connected to the 
upper rod carriage 52. The mounting block 54 slides along upper rods 56 in 
a substantially perpendicular direction from the abrading stations 22. 
Thus, the mounting block can be moved towards and away from the abrading 
devices 24, 26 and 28 in a smooth manner. The upper rod carriage 52 may 
also be moved parallel to the abrading stations 22 through the provision 
of a lower rod carriage 58. The lower rod carriage 58 and the upper rod 
carriage 52 are mounted to each other in overlapping relation. As the 
lower rod carriage 58 moves along an axis parallel to the abrading 
stations 22, it carries the upper rod carriage 52, as well as mounting 
block 54 and clamp 46. 
The lower rod carriage 58 is slidably connected to a series of lower rods 
60. The lower rods 60 are secured to plates 62 (see FIGS. 1 and 5) on the 
frame 18 and extend along an axis parallel to the abrading stations 22. 
Thus, as the lower rod carriage 58 moves along the lower rods 60, the 
lower rod carriage 58 moves parallel to the abrading devices 24, 26 and 
28. The upper rod carriage 52, attached to the lower rod carriage 58, 
moves in concert with the lower rod carriage 58. The upper rod carriage 52 
can thus be positioned adjacent to each of the belts of the abrading 
devices 24, 26 and 28. 
At some point, due to the length of rods 60, there may be some downward 
deflection of rods 60 as the carriages 52, 58 move therealong. In such 
instances rather than rods, a linear way is substituted therefore. The 
linear way includes a track mounted directly to surface 20 to avoid the 
possibility of downward deflection. The lower carriage 58 rides in 
longitudinal channels formed in the track and is provided with guides on 
its underside which provide smooth movement of the carriage along the 
track. 
The lower rod carriage 58 is protected from debris during the abrading 
process by a cover 64. Preferably, the cover 64 is flexible and has an 
accordion-like appearance. The cover 64 discourages debris such as metal 
shavings and the like discharged from the abrading stations 22 from 
collecting on the lower rods 60 and interfering with the movement of the 
lower rod carriage 58 along the lower rods 60. The cover 64 shrouds the 
full length of the lower rods 60 as seen in FIG. 1. As the rod carriages 
52 and 58 are moved laterally, the cover 64 flexibly moves with the rod 
carriages 52 and 58 compressing and expanding appropriately. As best seen 
in FIGS. 3-5, mounting block 54 extends almost directly under the needles 
12 to cover the front portion of the upper rod carriage 52. Mounting block 
54 discourages debris from collecting on the front portion of the upper 
rod carriage 52 and interfering with carriage 52 during positioning along 
rods 56. 
The needle clamp 46 is provided to hold one or a multiplicity of needles 
during engagement with the belt at each abrading station 22. A suitable 
needle clamp is that disclosed in copending U.S. application Ser. No. 
07/959,151, filed Oct. 9, 1992, entitled NEEDLE TRANSPORTING APATUS, 
the disclosure of which is incorporated herein by reference. Hydraulic 
cylinders 66 are provided and are operably connected to the upper and 
lower rod carriages 52 and 58. Needles 12 are held in the needle clamp 46 
and engage the belts at each abrading device 24, 26 and 28 in a controlled 
manner. Hydraulic cylinders 66 control the movement of upper and lower rod 
carriages 52 and 58 and the needle clamp 46 mounted thereon. Hydraulic 
cylinders 66 respond to instructions provided by an operator through 
operator interface 68 which sends electrical impulses to a programmable 
logic controller which activates hydraulic cylinders 66 via known 
mechanisms. Rod carriages 52 and 58 and the needle clamp 46, are thus 
capable of selective manipulation as will be described below. 
Further, the hydraulic cylinders 66 enable the needles 12 held in needle 
clamp 46 to be moved toward and away from each belt at predetermined time 
intervals via upper rods 56. In addition, the speed at which the needles 
are moved toward each belt, i.e., the plunge speed, can be controlled as 
desired. Where coarser abrasive belts are used, a quick plunge speed may 
be desired to control the amount of material removed from the needle and 
to avoid excessive heat build up. When the needles are being plunged into 
a polishing belt, a relatively slower plunge rate may be utilized since 
for the removal of scratches a slower plunge speed is preferred. The 
controlled movement of the upper rod carriage 52 along the upper rods 56 
enables the needles 12 to engage and disengage each belt for a short or 
long period of time, as well as, repetitive timed intervals if desired. 
Thus, the controlled and selectable movement of the rod carriages 52 and 
58 provides predeterminable grinding and abrading to achieve a specified 
needle cutting edge. 
It is further envisioned that other methods of moving the rod carriages 52 
and 58 may be used other than hydraulic cylinder 66, such as, methods 
utilizing pneumatics, servo-motors, and the like. 
Further, the hydraulic cylinders 66 can be used to manipulate the needles 
12 held in the needle clamp 46. Specifically, the needles 12 can be 
rotated while being held in the needle clamp 46. The needle clamp 46 
includes a movable jaw 70 and a stationary jaw 72, as best seen in FIG. 6. 
Manipulation of the movable jaw 70 laterally with respect to the 
stationary jaw 72 rotates the needles 12 therebetween, to apply cutting 
edges 16 to various sides of needle 12. 
The hoses leading to cylinders 66 are preferably positioned within a 
flexible articulated receptacle 74. The receptacle 74 is a linked housing 
which is positioned on the working surface 20 in an overlapped or folded 
manner and folds and unfolds as the needle holding mechanism 44 and clamp 
46 are moved laterally along lower rods 60. 
In operation, referring to FIGS. 3-5, the needles 12 held in the needle 
clamp 46 are positioned in an initial position substantially perpendicular 
to the first abrasive belt 30 of the first processing station 24, as shown 
in FIG. 3. The needle clamp 46 is placed on plate 55 and moved via upper 
carriage 52 on upper rods 56 in the direction of Arrow "A", as seen in 
FIG. 4, to a position tangential to the first belt 30 to engage the 
needles 12 with the first belt 30 for a selectable time interval or dwell 
period. In general, the needle clamp 46 preferably engages the needles 12 
with belt 30 for about 100 millisecond to about 30 seconds. 
The planar orientation of plate 55 can be adjusted by screw 59 thereby 
altering the attitude of the needles as they are presented to the belts. 
By turning screw 59 in one direction, plate 55 pivots upward about an axis 
defined by front edge 57 of plate 55 as the lower end of screw 59 contacts 
mounting block 54. Reversing the direction in which screw 59 is turned, 
plate 55 can be lowered. The planar orientation of plate 55 can preferably 
be adjusted in a range from 30.degree. above the horizontal to 30.degree. 
below the horizontal. It is also contemplated that the planar orientation 
of plate 55 can vary in a predetermined manner as the upper carriage 52 
moves toward the belt whereby the needles engage the belt at various 
angles during the plunge into the belt. 
Following grinding the needles 12 with the first belt 30, the needles 12 
may be moved away from belt 30, rotated as described above, and then moved 
to re-contact belt 30. Rotating the needles 12 enables different portions 
of the needle 12 to be engaged with the belt 30. 
After grinding the needles 12 at the first abrading device 24, the needles 
12 held in needle clamp 46 are returned to their initial position by 
moving upper carriage 52 along rods 56 in the direction of Arrow "A" away 
from belt 30, back to the position shown in FIG. 3. The needles 12 are 
then moved laterally as seen in FIG. 5 in the direction of Arrow "B" with 
carriages 52 and 58 via the lower rods 60 to a position substantially 
perpendicular to the second belt 34 of the second abrading device 26. The 
needles 12 are then moved towards second belt 34 to be tangentially 
engaged with the second belt 34 in essentially the same manner as with the 
previous first abrading device 24 by moving carriage 52 along rods 56 
towards belt 34, as indicated above with respect to FIG. 4. 
The second belt 34 preferably has an abrasiveness less than that of the 
first belt 30. Second belt 34 engages the incomplete cutting edge 16 of 
the needles 12 to further refine the cutting edge. Further, the length and 
frequency of the time intervals of needle engagement with the second belt 
34 may be adjusted in relation to those used with the first belt 30 for 
attaining optimum processing results. The needles 12 may also be rotated 
in a similar manner as described previously to further fashion a 
multi-sided cutting edge. 
After grinding of the needles 12 at the second abrading device 26, the 
needles are returned to their position substantially perpendicular to the 
second belt 34 so that they can be moved to the third abrading device 28. 
The needles 12 held in the needle clamp 46 are then moved via the lower 
rods 60 in a manner similar to that described above, to a position 
substantially perpendicular to the third belt 36. 
At the third abrading device 28, the needles 12 are tangentially engaged 
with belt 36 in a manner similar to that as disclosed in relation to the 
two previous abrading devices 24 and 26. However, the third belt 36 is 
preferably less abrasive than the first two belts 30 and 34 so that the 
cutting edge of the needles 12 can be deburred and polished. Preferably, 
belt 36 is a velvet flock belt which refines the cutting edge 16. 
After the cutting edges 16 of the needles 12 have engaged the polishing 
belt 36, the needle clamp 46 is returned to its initial position opposite 
the first processing station 24, as shown in FIG. 3, via the upper and 
lower rod carriages 52 and 58. 
Referring now to FIG. 6, the needle clamp 46 can then be removed from the 
mounting block 54. The needle clamp 46 is removably positioned on the 
mounting block 54, and a groove 76 in the stationary jaw 72 of the needle 
clamp 46 removably receives mounting bar 78 on mounting block 54. 
After the cutting edges 16 of the needles 12 have been applied by apparatus 
10, the needle clamp 46 is lifted off the mounting block 54, so that 
needles can then be removed from the needle clamp 46 by moving the lever 
48 upwardly to release the jaws 50 of the clamp 46 which hold the needles 
12. 
It is envisioned that other means for holding a needle or plurality of 
needles may be used, such as, a fixed clamp device, or a slotted element 
for receiving needles. 
It is further contemplated that the needle clamp 46 may be moved to 
desirable positions using other methods than the preferred embodiment 
described above. For example, slidable plates can be mounted on the lower 
rod carriage 58 and be used instead of the upper rod carriage 52. The 
slidable plates may be configured and dimensioned to receive the needle 
clamp 46 and slide in relation to one another such that the clamp can be 
moved towards and away from the processing stations. 
It is evident from the above described preferred embodiment that various 
belt speeds and belt abrasiveness may be used, as well as various 
selectable timed intervals of needle engagement with the belts. 
In addition to using abrasive belts, grinding wheels are a useful 
alternative, particularly where various grinding profiles are desired to 
be imparted to the needle blanks. The grinding wheel of the present 
invention is preferably fabricated from a preformed substrate to which an 
abrasive is bonded. In a particularly useful embodiment, the substrate is 
made from a metal or alloy, such as, for example, an aluminum-based 
material, and has an abrasive coating bonded to it by electroplating. The 
abrasives used for such bonding are diamond or cubic boron nitride 
("CBN"), available under the tradename Borazon. Electroplated wheels may 
be manufactured to provide any custom design or according to any given 
specification and therefore, offer immediate fast cutting as purchased 
without the need for manual dressing of the grinding wheel prior to use. 
The cutting edges of super-abrasive materials do not break off as do those 
of conventional bonding materials. Instead, they wear down gradually over 
a long period of time. Therefore, grinding wheels plated with the 
above-mentioned abrasives provide the exact grinding surface geometry 
required for precision grinding. The variations inherent in the manual 
dressing or re-dressing to generate and retain the form of conventional 
bonded grinding wheels are not introduced into the needle forming process 
in the preferred embodiments of the present invention. In addition, in the 
preferred embodiments, no break-in period is required and wheel cores are 
reusable, thus reducing replacement costs. 
FIGS. 12 and 13 illustrate a portion of a needle blank 80 which has a 
triangular cross-sectional shape with three flat sides 82. The triangular 
cross-sectional shape may be imparted to the needle blank using any 
conventional means such as, for example, pressing or grinding. The term 
"needle blank" refers to the material from which the needle is formed, 
(i.e. the linear piece of metal which can be ground, pointed and polished, 
etc.) to form a finished needle and includes the intermediate material on 
which one or more processing steps has already been performed. Needle 
blank 80 may be fabricated from any alloy suitable for use in surgical 
needles such as stainless steel. The purpose of the grinding wheel of the 
present invention is to "hollow grind" the sides into a concave 
configuration as shown in FIGS. 14 and 15. One can readily see that edges 
84 of the needle 80 in FIG. 15 can be ground and polished to a higher 
degree of sharpness than edges 84 of flat sided needle 80 of FIG. 13. An 
end of the needle blank may also be simultaneously tapered into a sharp 
point. FIGS. 14 and 15 illustrate a needle blank 80 which has been 
pressed, hollow ground to form sharp edges 84, and tapered to a sharp 
point 86. 
The grinding wheel 88 of the present invention is illustrated in FIGS. 16, 
17 and 18, to which are now referred. The dimensions given below should 
not be considered as limitations of the invention, but only as 
exemplifications of preferred embodiment(s) thereof. Any dimensions 
suitable for the purposes described herein may be employed with the 
appropriate tolerances. Grinding wheel 88 comprises a generally 
cylindrical shaft 90 having a first end portion 92, a second end portion 
94, a plurality of circumferentially extending grinding ridges 96 
extending circumferentially around middle portion 98, and an aperture or 
bore 100. The outer diameter D-1 of the wheel 88 is preferably from about 
0.7500 inches to about 2.5000 inches and, in a more preferred embodiment, 
about 1.1250.+-.0.001 inches. The length L-16 of grinding wheel 88 is 
preferably from about 2.0000 inches to about 6.0000 inches, and in a more 
preferred embodiment, is about 4.0000.+-.0.0001 inches. 
The longitudinally extending aperture 100 has first, second and third inner 
surface portions. A first inner surface portion 102 generally defines a 
cylinder having a diameter D-2 of from about 0.5000 to about 2.0000 
inches. A second inner surface 104 defines a cylinder having a diameter 
D-4 of from about 0.2500 inches to about 1.0000 inches. A third inner 
surface 106 defines a generally frustoconical shape having a smaller 
diameter equal to the diameter D-4 of the second inner surface and a 
larger diameter D-3 of from about 0.5000 inches to about 1.5000 inches. 
The third inner surface is inclined from the axial or longitudinal center 
line by an angle A-1 of from about 5 degrees to about 15 degrees. 
The length L-17 of the first end portion 92 can be from about 0.1000 inches 
to about 0.5000 inches. 
The ridges 96 each are defined by an apex 108 formed at the conjunction of 
sides 110 and 112. The needle blanks are contacted to respective apexes to 
achieve the hollow grind of the needle. Angle A-2 formed by sides 110 and 
112 can be from about 90 degrees to about 175 degrees. Preferably the 
angle formed by the sides of the ridges is between about 140 and 160 
degrees and is most preferably about 150 degrees. In a preferred 
embodiment, the apexes are spaced apart from the first end by the 
respective distances L-1 to L-15 as set forth in Table A below. The apexes 
are spaced apart from each other a distance of 0.1875 inches, as can be 
seen from Table A. Tolerances should be .+-.0.0001 inches. 
TABLE A 
______________________________________ 
Designation Dimension (inches) 
______________________________________ 
L-1 0.5875 
L-2 0.7750 
L-3 0.9625 
L-4 1.1500 
L-5 1.3375 
L-6 1.5250 
L-7 1.7125 
L-8 1.9000 
L-9 2.0875 
L-10 2.2750 
L-11 2.4625 
L-12 2.6500 
L-13 2.8375 
L-14 3.0250 
L-15 3.2125 
______________________________________ 
The needle blanks 80 are preferably held in a support frame in side by side 
spaced apart relation, each needle being supported so as to contact a 
respective one of the apexes of the ridges 96 while the grinding wheel 88 
is rotated around its longitudinal axis. 
The grinding wheel 88 is preferably spun at from about 1,000 rpm to about 
15,000 rpm to accomplish the grinding. Each side 82 of the needle blanks 
is, in turn, ground to produce the hollowed out (i.e. concave) shape 
oriented along the length of the needle blank as shown in FIG. 13. The end 
of the needle blank may simultaneously be tapered by grinding to a sharp 
point 86 as shown in FIG. 14. 
FIG. 19 illustrates a fixture 114 for holding a plurality of needle blanks 
80. The needle blanks 80 preferably have a triangular cross section. 
The holding fixture 114 includes two flat parallel plates 116 and 118 
between which needles 80 are frictionally held. Groves may be provide in 
one of the plates to ensure accurate placement of the needle blanks in 
relation to the ridges on the grinding wheel. The spacing of the needles 
within the jaws of the holder may correspond to the spacing of the ridges 
96 on grinding wheel 88. The needle blanks may be placed within the plates 
of the holder and contacted with the grinding wheel. When grinding is 
complete on one flat side of the needle blank, the blanks may be manually 
rotated within the holder so that another flat face of the needle blank is 
positioned for contact with the grinding wheel. When grinding of the 
second face is complete, the process may be repeated to hollow grind the 
third face. 
Preferably, one of plates 116 is laterally movable with respect to the 
other 118, as shown by arrows B. Lateral movement of plate 116 causes the 
needle blanks 80 to simultaneously rotate along their respective 
longitudinal axes, each thereby flipping over to another side. Thus, the 
needles 80 are placed in holder 114, which is thereafter positioned in a 
grinding apparatus for hollow grinding and tapering one side of the 
exposed ends of the needles 80. Then, plate 116 is laterally moved to turn 
the needles over and another side is ground and tapered. Finally, the 
needles are once again turned and the third side is ground and tapered. 
Most preferably, the needle blanks are rotated on their longitudinal axis 
within the holder such that essentially no lateral movement of the needle 
blank occurs during rotation. When rotation directly on the axis of the 
needle blank is achieved, the holder need only be precisely oriented with 
respect to the grinding wheel once, since the position of the needle blank 
does not change as other faces of the needle blank are presented for 
grinding. A particularly useful holder for providing rotation of the 
needle blanks on their longitudinal axis with essentially no translational 
movement is described in U.S. application Ser. No. 07/959,151, filed Oct. 
9, 1992, entitled NEEDLE TRANSPORTING APATUS, the disclosure of which 
is incorporated herein by reference. 
The needles may optionally be polished on another wheel having a polishing 
surface configured and dimensioned similar to grinding wheel 88. 
While the above description contains many specifics, these specifics should 
not be construed as limitations on the scope of the invention, but merely 
as exemplifications of preferred embodiments thereof. Those skilled in the 
art will envision many other possible variations that are within the scope 
and spirit of the invention as defined by the claims appended hereto. For 
example, while the invention has been described in terms of the preferred 
electroplated grinding wheels, it should be understood that other types of 
wheels having the disclosed geometry may be employed, such as, for example 
solid vitrified CBN wheels. 
Referring to FIGS. 20-22 there is illustrated a second preferred embodiment 
of an apparatus 120 for applying a cutting edge to surgical needles. 
Apparatus 120 is particularly suited for use with hollow grinding wheel 88 
of FIGS. 16 to 18. Apparatus 120 applies at least one cutting edge 84 on 
blank 80, and in a preferred embodiment, three edges 84 are applied as 
seen in FIGS. 13-15. 
Referring to FIG. 20, the apparatus 120 includes a frame or table 122 
having a working surface 124. The apparatus 120 comprises a series of 
abrading stations 126 positioned on work surface 124 for abrading a 
multiplicity of needles to apply cutting edges thereon. Abrading stations 
126 refine needle blank 80 in sequential stages using rotating abrasive 
devices such as grinding belts or grinding stones and wheels. Each 
abrading device of station 126 preferably represents a predetermined stage 
of needle refinement. 
As with apparatus 10 above, the present embodiment of apparatus 120 
processes a needle blank 80 to result in three cutting edges 84 utilizing 
three separate abrading devices 128, 130 and 132. Alternative embodiments, 
however, may have more or less than three abrading devices, and further 
may provide cutting edges on more or less than three sides. 
Apparatus 120 includes three rotatable abrading stations 126, preferably 
utilizing the above mentioned grinding wheels 88, positioned laterally 
adjacent to and along a common axis with each other. Abrading devices 128, 
130 and 132 are rotated by motors 134, 136 and 138 by means of belts 135, 
137 and 139 at predetermined speeds. Preferably grinding wheels 88 are 
similar to grinding wheel 88 described hereinabove having 150.degree. 
ribs. Further, in the preferred embodiment, the first grinding station has 
a rough hollow grind wheel, the second station has a medium hollow grind 
wheel and the third station has a hollow grind polishing wheel. 
A fourth station 140 may comprise a velvet flock belt 142 to provide for 
deburring and polishing. A motor 141 is provided to rotate belt 142. 
However, deburring may also be accomplished by reversing the direction of 
third wheel 88. Also, the speed of motor 138 may be adjusted for optimum 
polishing of the cutting edge. 
Each of abrasive wheels 88 at abrading devices 128, 130 and 132 preferably 
have an abrasiveness having micron values of between about 0.3 microns to 
about 100 microns. While abrasive wheels are preferred, it is also 
contemplated that abrasive belts may also be employed. 
As mentioned with respect to apparatus 10 above, it is also contemplated 
that an alternative apparatus may include any number of abrading devices 
for fashioning a cutting edge on a needle blank instead of a series of 
processing stations. The envisioned alternative apparatus may include a 
variable speed motor for rotating an abrasive wheel at different speeds. 
Referring now to FIGS. 21 and 22, a needle holding mechanism 144 is shown 
which includes a needle clamp 146 dimensioned and configured to hold at 
least one needle blank 80, or a multiplicity of needles 80 as shown in 
FIG. 20. Needles 80 are releasably held in clamp 146, which may be 
disengaged to remove needles 80 from clamp 146. This is accomplished by 
moving lever 148 upwardly to open jaws 150 of needle clamp 146. 
Needle holding mechanism 144 comprises an upper rod carriage 152 having a 
mounting block 154 for positioning needle clamp 146 thereon. Preferably 
clamp 146 is detachably mounted on a plate 153 affixed to mounting block 
154. Mounting block 154 is slidably positioned on upper rods, similar to 
rods 56 in apparatus 10 above, connected to upper rod carriage 152. 
Mounting block 154 slides along upper rods in a direction substantially 
perpendicular to the abrading stations 126. Thus, mounting block 154 can 
be moved towards and away from abrading devices 128, 130 and 132 in a 
smooth manner. 
Immediately below upper rod carriage 152, and slidably mounted thereto, is 
a vertical plunge plate 156 which is mounted upon and moves along an 
angled track 158. Vertical plunge plate is provided to alter the height of 
needle clamp 146 during the grinding sequence thereby providing an 
additional axis of motion in a vertical direction. By moving vertical 
plunge plate 156 along track 158 upper rod carriage 152, and thus needle 
clamp 146, may be moved upwardly and inwardly or rearwardly and 
downwardly. Preferably, angled track 158 is oriented at an angle of from 5 
degrees to 30 degrees with respect to work surface 124 and move preferably 
at an angle of 9 degrees. 
Upper rod carriage 152 and vertical plunge plate 156 may also be moved 
parallel to abrading stations 126 through the provision of a lower rod 
carriage 160. Lower rod carriage 160 and track 158 are mounted to each 
other in overlapping relation. As lower rod carriage 160 moves along an 
axis parallel to abrading stations 126, as shown in FIG. 20, it carries 
vertical plunge plate 156 and upper rod carriage 152, as well as mounting 
block 154 and clamp 146. 
As with apparatus 10 above, lower rod carriage 160 is slidably connected to 
a series of lower rods 161 extending along an axis parallel to abrading 
stations 126. Thus, as lower rod carriage 160 moves along lower rods 161, 
lower rod carriage 160 moves needle holding mechanism parallel 144, of 
which lower rod carriage 160 is a part, to abrading devices 128, 130 and 
132. Thus upper rod carriage 152 can be positioned adjacent to each of 
wheels 88 of abrading devices 128, 130 and 132. 
As above, a linear way may be substituted for the rods. The linear way 
includes a track mounted directly to surface 124 to avoid the possibility 
of downward deflection. Lower carriage 160 rides in longitudinal channels 
formed in the track and is provided with guides on its underside which 
provide smooth movement of the carriage along the track. 
Lower rod carriage 160 and vertical plunge plate 156 are also protected 
from debris during the abrading process by a flexible cover 162. As needle 
holding mechanism 144 is moved laterally, cover 162 flexibly moves with 
upper rod carriage 52 and vertical plunge plate 156 compressing and 
expanding appropriately to prevent accumulation of debris. 
As above, a suitable needle clamp for use with the present embodiment is 
that disclosed in copending U.S. application Ser. No. 07/959,151, filed 
Oct. 9, 1992 entitled NEEDLE TRANSPORTING APATUS, the disclosure of 
which is incorporated herein by reference. 
Hydraulic cylinders 164 are provided and are operably connected to upper 
and lower rod carriages 152 and 160, respectively, and vertical plunge 
plate 156 by means of hoses 165. Hydraulic cylinders 164 respond to 
instructions provided by an operator through operator interface, similar 
to interface 68 with respect to apparatus 10 hereinabove, which sends 
electrical impulses to a programmable logic controller which activates 
hydraulic cylinders 164 via known mechanisms. A computer numerical 
controller (CNC) is used to control motions, such as, for example X 
(station to station), Y(in and out feed), z(vertical) and U(rotation of 
needles in clamp) thus providing 4 axes of motion to needles 80. 
Preferably the movements are in increments of one ten thousandth of an 
inch. Rod carriages 152 and 160, vertical plunge plate 156 and needle 
clamp 146, are thus capable of selective manipulation as will be described 
herein below. 
Further, hydraulic cylinders 164 enable needles 80 held in needle clamp 146 
to be moved toward and away from each wheel 88 at predetermined time 
intervals via the upper rods. In addition, the speed at which needles 80 
are moved toward each wheel 88, i.e., the plunge speed, can be controlled 
as desired. In addition to the speed of the plunge, the vertical height of 
needles 80, relative to grinding wheels 88, may be altered during the 
plunge by moving vertical plunge plate 156 along track 158 during the 
grinding sequence. This is particularly useful where it is desired to 
alter the depth of the grinding groove in a face of needle 80 to provide a 
tapered or elliptical groove. 
For example, as needle 80 is plunged into grinding wheel 88, wheel 88 may 
cut deep and close to the needle axis, by moving vertical plunge plate 156 
rearwardly, in the direction of arrow B in FIG. 22, and thus downwardly 
along track 158, the depth of the grind in a facing surface of needle 80 
may be reduced as needle blank 80 is advanced into grinding wheel 88. 
Since vertical plunge plate 156 also moves rearwardly during this 
sequence, the inward movement of upper rod carriage 152 must be increased 
in an amount sufficient to offset the rearward movement of vertical plunge 
plate 156 in order to maintain a consistent inward plunge speed and thus 
allow a downward vertical move along with the inward plunge. 
The controlled movement of upper rod carriage 152 along the upper rods, 
along with vertical plunge plate 156, enables needles 80 to engage and 
disengage each wheel 88 for a short or long period of time, as well as, 
repetitive timed intervals and depth of cuts if desired. Thus, the 
controlled and selectable movement of rod carriages 152 and 160 and 
vertical plunge plate 156 provides a variable and predeterminable grinding 
and abrading sequence to achieve a specified needle cutting edge profile. 
As above, it is further envisioned that other methods of moving rod 
carriages 152 and 160 and vertical plunge plate 156 may be used other than 
hydraulic cylinder 164, such as, methods utilizing pneumatics, 
servo-motors, and the like. 
Jaws 150 may be comprised of movable upper plate 116 and stationary lower 
plate 118 described hereinabove. Manipulation of movable plate 116 
laterally with respect to stationary plate 118 rotates needles 80 
therebetween to present successive sides 82 of needles 80 to wheel 88 in 
order to apply cutting edges 84 to various sides 82 of needle 80. 
In operation, referring to FIGS. 20-22, needles 80 held in the needle clamp 
146 are positioned in an initial position substantially perpendicular to, 
and slightly below, first abrasive wheel 88 of the first processing 
station 126, as shown in FIG. 21. Needle clamp 146 is placed on plate 153 
and moved via upper rod carriage 152 on upper rods in the direction of 
Arrow "A", as seen in FIG. 22, to a position tangential to first wheel 88 
to engage needles 80 with first wheel 88 which rotates in the direction of 
arrow "R" for a selectable time interval or dwell period. Additional 
inward and upward positioning may be obtained by initially moving vertical 
plunge plate 156 inward in the direction of arrow C in FIG. 21. In 
general, needle clamp 146 preferably engages needles 80 with wheel 88 for 
about 1.0 millisecond to about 5.0 seconds. 
The planar orientation of plate 153 can be adjusted by screw 166 thereby 
altering the attitude of needles 80 as they are presented to wheels 88. 
The vertical orientation of plate 156 can be varied in a predetermined 
manner by means of vertical plunge plate 156, and thus needle clamp 146 
and needles 80, as upper rod carriage 152 moves toward wheel 88 whereby 
needles 80 engage wheel 88 at various heights during the plunge into wheel 
88. 
Following grinding needles 80 with first wheel 88, needles 80 may be moved 
away from wheel 88, rotated between plates 116 and 118 as described 
hereinabove, and then moved to re-contact wheel 88. Rotating needles 80 
enables different sides 82 of needle 80 to be engaged with the wheel 88. 
After grinding needles 80 at first abrading device 128, needles 80 held in 
needle clamp 146 are returned to their initial position by moving upper 
rod carriage 152 along the rods away from wheel 88. Needles 80 are then 
moved laterally to a position substantially perpendicular to second wheel 
88 of second abrading device 130. Needles 80 are then moved towards second 
wheel 88 to be tangentially engaged with second wheel 88 in essentially 
the same manner as with the previous first abrading device 128 by moving 
upper rod carriage 152 along the rods 56 towards wheel 88. 
Second wheel 88 preferably has an abrasiveness less than that of first 
wheel 88. Second wheel 88 engages the incomplete cutting edge 84 of 
needles 80 to further refine the cutting edge. 
After grinding of needles 80 at the second abrading device 130, needles 80 
are returned to their position substantially perpendicular to second wheel 
88 so that they can be moved to third abrading device 132. Needles 80 held 
in needle clamp 146 are then moved via lower rods 161 in a manner similar 
to that described above, to a position substantially perpendicular to 
third wheel 88. 
At third abrading device 132, needles 80 are tangentially engaged with 
wheel 88 in a manner similar to that as disclosed in relation to the two 
previous abrading devices 128 and 130. However, third wheel 88 is 
preferably less abrasive than the first two wheels 88 so that the cutting 
edge of needles 80 can be deburred and polished. 
Finally, after grinding of needles 80 at third abrading device 132, needles 
80 are returned to their position substantially perpendicular to third 
wheel 88 so that they can be moved to a deburring and polishing belt 142. 
Belt 142 is a velvet flock belt which refines cutting edge 84. 
After cutting edges 84 of needles 80 have engaged polishing belt 142, 
needle clamp 146 is returned to its initial position opposite the first 
processing station 128, similar to that of apparatus 10 as shown in FIG. 
3, via upper and lower rod carriages 152 and 160. 
After cutting edges 84 of needles 80 have been applied by apparatus 120, 
needle clamp 146 is lifted off mounting block 154, so that needles 80 can 
then be removed from needle clamp 146 by moving lever 148 upwardly to 
release jaws 150 of clamp 146 which hold needles 80. 
It is envisioned that other means for holding a needle or plurality of 
needles may be used, such as, a fixed clamp device, or a slotted element 
for receiving needles. 
Additionally, a simple block type clamp may be provided to hold a dressing 
tool for dressing the grinding wheels back to the proper angle. Preferably 
a diamond tool may be provided to fix all the grooves at once (a plunge 
dresser) or to fix a single groove (a single point dresser). 
It is further contemplated that needle clamp 146 may be moved to desirable 
positions using other methods described herein above. 
It is evident from the above described preferred embodiment that various 
wheel speeds and wheel abrasiveness may be used, as well as various 
selectable timed intervals of needle engagement with the wheels. 
While the invention has been particularly shown, and described with 
reference to the preferred embodiments, it will be understood by those 
skilled in the art that various modifications and changes in form and 
detail may be made therein without departing from the scope and spirit of 
the invention. Accordingly, modifications such as those suggested above, 
but not limited thereto, are to be considered within the scope of the 
invention.