Surgical blade abstract
A holder assembly for a surgical blade includes a handle assembly
and a wrench for loosening/tightening the blade from/to the handle
of the handle assembly. The handle assembly includes a collet having
two longitudinal slits that enable the collet to secure the blade
in a first and second direction to prevent slippage during operation.
The collet fits in the handle and is secured by a retaining member
that fits over the collet with the blade intact. The retaining member
is loosened/tightened by a wrench that is part of the holder assembly.
The wrench is configured to cover the blade completely when the
wrench is placed in operation. Part of the cover is removable for
cleaning by inserting the closed end of the wrench into the wrench
body and pushing the cover's cap off.
Surgical blade claims
What is claimed is:
1. A handle assembly for holding a blade having a generally rectangular
cross sectional configuration with opposing substantially planar
parallel sides and substantially planar parallel opposing edges,
the assembly comprising:
a substantially elongate handle having first and second opposite
ends, wherein the first end is open;
an elongated collet having a longitudinal axis and inner walls
defining a substantially rectangular axial passage and first and
second opposite ends, the collet having a first longitudinal slit
extending from the first end for receiving a blade into the axial
passage and forming a first set of opposed substantially planar
parallel jaws that are compressible for gripping the opposing planar
sides of the blade, and further having a second longitudinal slit
extending from the second end and forming a second set of opposed
substantially planar parallel jaws that are compressible for gripping
opposing planar edges of the blade; and
an elongated retaining member having first and second opposite
open ends and a longitudinal axis with a longitudinal inner passage,
the retaining member mounted at the first end of the handle and
being configured to secure the collet and apply a compressive force
to the collet, the retaining member having an inside surface and
an outside surface.
2. The handle assembly of claim 1 wherein the collet is substantially
conically shaped.
3. The handle assembly of claim 2 wherein the substantially conical
collet is composed of two opposing cones each having a frustum and
a tip, each frustum being adjacent to the other frustum and the
tip of one cone being at the first end of the collet and the tip
of the other cone being at the second end of the collet.
4. A combination for safely securing and loosening the retaining
member to and from the handle assembly of claim 1 the combination
comprising:
the handle assembly of claim 1; and
a combined wrench and protective shield member, the wrench and
protective shield member including:
a body having first and second opposite ends and a longitudinal
axis and a covered axial passage for covering the blade; and
the first end of the body being open for receiving the blade into
the axial passage and having an inside surface that is configured
to enable twisting of the retaining member in a first direction
to secure the retaining member to the handle and in a second direction
to loosen the retaining member from the handle.
5. A handle assembly for holding a blade having a opposing sides
and opposing edges, the assembly comprising:
a substantially elongate handle having first and second opposite
ends, wherein the first end is open;
an elongated collet having a longitudinal axis and inner walls
surrounding an axial passage and first and second opposite ends,
the collet having a first longitudinal slit extending from the first
end for receiving a blade into the axial passage and forming a first
set jaws that are compressible for gripping opposing sides of the
blade, and further having a second longitudinal slit extending from
the second end and forming a second set of jaws that are compressible
for allowing the inner walls to grip opposing edges of the blade;
an elongated retaining member having first and second opposite
open ends and a longitudinal axis with a longitudinal inner passage,
the retaining member mounted at the first end of the handle and
being configured to secure the collet and apply a compressive force
to the collet, the retaining member having an inside surface and
an outside surface;
a combined wrench and protective shield member, the wrench and
protective shield member comprising:
a body having first and second opposite ends and a longitudinal
axis and a covered axial passage for covering the blade; and
the first end of the body being open for receiving the blade into
the axial passage and having an inside surface that is configured
to define coupling means for enabling twisting of the retaining
member in a first direction to secure the retaining member to the
handle and in a second direction to loosen the retaining member
from the handle, wherein the second end of the combined wrench and
protective shield member's body has a removable insert that can
be removed in order to allow cleaning of the axial passage.
6. The combination of claim 5 wherein a portion of the handle
near the second end of the handle is dimensioned to fit into the
axial passage of the combined wrench and protective shield member
so that the second end of the handle can be used to remove the removable
insert of the body.
7. The combination of claim 4 wherein the retaining member of
the handle assembly has outside surface ridges and valleys between
the ridges.
8. The combination of claim 7 having inside surface ridges and
valleys disposed near the first end and being keyed to match the
corresponding ridges and valleys of the retaining member so that
twisting the wrench twists the retaining member.
9. The combination of claim 4 wherein the combined wrench and
protective shield member's body is composed of a first cylindrical
portion having a diameter and a second cylindrical portion having
a diameter, wherein the first cylindrical portion extends from the
first end of the combined wrench and protective shield member to
the beginning of the second cylindrical portion that extends to
the second end of the combined wrench and protective shield member
and the diameter of the second portion is greater than the diameter
of the first portion.
10. The handle assembly of claim 1 wherein the retaining member
has a threaded portion in the internal passage.
11. The handle assembly of claim 10 wherein the handle has a threaded
portion at the first end for receiving the threaded portion of the
retaining member.
12. A collet for a handle assembly configured to hold a blade having
a generally rectangular cross sectional configuration with opposing
substantially planar parallel sides and opposing substantially planar
parallel edges, wherein the handle assembly has a substantially
elongate handle having first and second opposite ends and the first
end is open, the handle assembly further having a retaining member
for securing the collet in the first open end of the handle, the
collet comprising:
an elongated body having a longitudinal axis and inner walls defining
a substantially rectangular axial passage and first and second opposite
ends, the collet further having a first longitudinal slit extending
from the first end for receiving a blade into the axial passage
and forming a first set of opposed substantially planar parallel
jaws that are compressible by the retaining member for gripping
opposing sides of the blade, and further having a second longitudinal
slit extending from the second end and forming a second set of opposed
substantially planar parallel jaws that are compressible by the
retaining member for gripping opposing edges of the blade.
13. The collet of claim 12 wherein the first longitudinal slit
and the second longitudinal slit each extend from the respective
first and second opposite ends such that the span of each slit overlaps
the span of the other slit.
14. The collet of claim 12 wherein the first longitudinal slit
is angular, displaces relative to the longitudinal axis and is offset
by an angle from the second longitudinal slit.
15. The collet of claim 14 wherein the offset angle is ninety
degrees.
16. A handle assembly for holding a blade having a generally rectangular
cross sectional configuration with opposing substantially planar
parallel sides and opposing substantially planar parallel edges,
the assembly comprising:
a substantially elongate handle having first and second opposite
ends, wherein the first end is open;
an elongated substantially conical collet having a longitudinal
axis and inner walls defining a substantially rectangular axial
passage and first and second opposite ends, the collet having a
first longitudinal slit forming a first set of opposing substantially
planar parallel jaws that are extending from the first end for receiving
a blade into the axial passage and wherein the first set of jaws
are compressible for gripping opposing sides of the blade, and further
having a second longitudinal slit extending from the second end
and forming a second set of opposing substantially planar parallel
jaws that are compressible for gripping opposing edges of the blade;
and
an elongated retaining member having first and second opposite
open ends and a longitudinal axis with a longitudinal inner passage,
the retaining member mounted at the first end of the handle and
being configured to secure the collet and apply a compressive force
to the collet, the retaining member having an inside and an outside.
17. The handle assembly of claim 16 wherein the collet is composed
of two opposing cones having adjacent frustums meeting near the
center of the collet with each cone facing in opposite directions
such that a tip of one cone is at the first end and a tip of the
other cone is at the second end of the collet.
18. The handle assembly of claim 16 wherein the first longitudinal
slit and the second longitudinal slit each extend from the respective
first and second opposite ends such that the span of each slit overlaps
the span of the other slit.
19. The handle assembly of claim 16 wherein the first longitudinal
slit is angularly displaced relative to the longitudinal axis and
is offset by an angle from the second longitudinal slit.
20. The handle assembly of claim 19 wherein the offset angle is
ninety degrees.
21. A method for making a handle assembly for holding a blade having
a generally rectangular cross sectional configuration with opposing
substantially parallel sides and substantially parallel opposing
edges, the method composing the steps of:
providing a substantially elongate handle having first and second
opposite ends, wherein the first end is open;
providing an elongated collet having a longitudinal axis and inner
walls defining a substantially rectangular axial passage and first
and second opposite ends, the collet having a first longitudinal
slit extending from the first end for receiving a blade into the
axial passage and defining a first set of opposed parallel jaws,
the first jaws being compressible for gripping opposing sides of
the blade, and further having a second longitudinal slit extending
from the second end and defining a second set of opposed parallel
jaws, the second jaws being compressible for gripping opposing edges
of the blade;
providing an elongated retaining member having first and second
opposite open ends and a longitudinal axis with a longitudinal inner
passage; and
mounting the retaining member at the first end of the handle to
secure the collet and apply a compressive force to the collet.
Surgical blade description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to surgical instruments and more
specifically to an assembly for holding a surgical blade that improves
the safety of using such blades.
2. Description of the Related Art
Surgical instruments and, in particular, blades are required to
be extremely sharp in order to make incisions and the like. Unfortunately,
the sharp instruments are a safety hazard to the people who use
them. A cut to a doctor, nurse, or other medical personnel exposes
the medical person to viruses and other infections that can enter
the person's body through the open cut. Additionally, the cut may
cause blood to contaminate the blade which exposes other persons,
including patients, to the risk of exposure to these harmful contaminants.
Some viruses are lethal; for example, there is no known cure for
infection by the Human Immunodeficiency Virus (HIV) that causes
Acquired Immunodeficiency Syndrome (AIDS) and HIV is known to infect
human blood. AIDS is a terminal condition, killing those who have
acquired it by destroying the immune system so that the infected
sufferer dies from AIDS related symptoms, such as pneumonia, that
their body is unable to fend off. Because of the risk of such deadly
infections, there is a long-felt need for medical instruments that
are safe to clean and use.
One cause of injury by surgical tools is caused by a blade that
is not securely held in place in its handle. Surgery tends to be
very stressful on the cutting instrument due to odd cutting angles
that are sometimes necessary and the force required to make an incision.
Prior art surgical devices exhibit a tendency for the blade to be
dislodged from its holder in such a situation. The inventors of
the present invention have made the critical recognition that a
significant factor contributing to this problem is that prior art
surgical instruments hold the blade secure in only one direction.
Thus, a substantial force introduced in another plane on the blade
may dislodge it from its handle.
Another type of injury caused by sharp surgical blades occurs when
the are being placed in or removed from their handles. Typically
such blades are placed in a handle and a nut is tightened around
a securing member to hold them in place. The nut is usually tightened
with an open-end or boxed-end wrench. Any slippage by the operator,
when tightening the nut, immediately exposes the operator to the
risk of being cut by the sharp blade. A similar risk exists when
the blade is being removed with such a wrench. What is needed is
a wrench and blade handle assembly combination that allows for insertion/removal
without exposing the operator to the risk of injury. Furthermore,
such an advantage provided with a blade handle assembly that also
prevents the slippage of such blades during operation would be a
significant advancement in the art.
Because of the risk of exposure to contaminants in human blood,
described above, it is essential that all instruments used in surgical
operations be cleaned thoroughly before being re-used. Since a wrench
used to remove the blade may become contaminated it must be cleaned
after use. However, the inventors have made the critical recognition
that there is a tension between the need to somehow shield the operator
from the blade during insertion/removal and the need to clean the
wrench because a wrench configured with extra parts for such prophylactic
measures will be more difficult to clean than one that has no cover.
Thus, it would be an advancement in the art to provide the advantages
described above while enabling easy cleaning of the entire assembly
including the wrench.
SUMMARY OF THE INVENTION
An objective of this invention is to provide an improved surgical
blade holder that overcomes the problems described above. To meet
this objective, and to this invention provides novel embodiments
of a handle assembly tool to allow for safe installation/removal
of blades from the assembly. The assembly includes a handle having
an open end for receiving a collet configured to secure a cutting
blade in two directions. The collet has longitudinal slits near
the front and rear. The longitudinal slit near the front receives
the blade into the body of the collet. A retaining member placed
over the collet and turned in one direction compresses the collet
including the slits. The compression of one slit causes gripping
of the blade on opposing sides and the compression of the other
causes gripping of the edges of the blade. One optional aspect of
the invention is a combination of the handle assembly with a wrench
and protective shield combination that enables removal/insertion
of the collet and fits over the blade in the collet. The tool has
a covered part that encloses the blade covering its sharp edges
to prevent injury. Another portion of the wrench tool is configured
to twist the retaining member in one direction for securing the
blade and in an opposite direction for allowing removal of the blade.
In a preferred embodiment, the wrench tool has a removably closed
end disposed opposite an end that is configured to twist the retaining
member. Other objects and advantages of this invention will be readily
appreciated upon reading the following description in view of the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
The objects, advantages and features of the present invention will
be more clearly understood by reference to the following detailed
disclosure when read in conjunction with the accompanying drawing,
in which:
FIG. 1 is a perspective view of the handle assembly of the present
invention holding a blade having opposing sides and opposing edges;
FIG. 2 is an isometric view of a wrench for securing and loosening
the retaining member of the handle assembly of FIG. 1 shown engaging
the retaining member attached to the handle member of the handle
assembly of FIG. 1;
FIG. 3 is an isometric view of the wrench of FIG. 2 with the handle
assembly removed and a hidden view of the removable insert of the
wrench shown;
FIG. 4 is a top plan view of the wrench of FIGS. 2 and 3 showing
the open end for receiving the retaining member and blade of FIG.
1;
FIG. 5 is a partial sectional side view taken along line 5--5 of
the wrench shown in FIG. 4;
FIG. 6 is an isometric view showing the removable insert of the
wrench being removed by the closed end of the handle of FIG. 1;
FIG. 7 is an exploded view of the handle assembly of FIG. 1 showing
the handle, the collet, the retaining member, and a blade;
FIG. 8 is a partial sectional view of the collet secured in the
handle by the retaining member and engaging a blade in a longitudinal
slit;
FIG. 9 is a partial sectional view of the collet, blade, retaining
member and handle of FIG. 8 showing another longitudinal slit; and
FIG. 10 shows opposing sides and opposing edges of the blade of
FIG. 1 with force vector shown to indicate the securing compressive
forces enabled by the longitudinal slits of FIG. 8 and FIG. 9 when
the collet is placed in the handle and the retaining member is turned
in a securing direction.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
This invention is described with reference to a preferred embodiment
shown in the drawing figures. In these figures, a like number shown
in various figures represents the same or similar elements in each
figure. While this invention is described in terms of the best mode
for achieving this invention's objectives, it will be appreciated
by those skilled in the art that variations may be accomplished
in view of these teachings without deviating from the spirit or
scope of the invention.
Handle Assembly Overview
FIG. 1 shows a handle assembly designated generally by the numeral
12 for holding a blade 14 in a secure safe position. As will be
described in detail below with reference to FIG. 7 the collet 16
holds the blade 14 secure in two directions gripping both opposing
sides and opposing edges of the blade. Such a safe securing operation
has not been achieved by the prior art and this is a novel non-obvious
aspect of this invention. The collet 16 has a longitudinal slit
18 extending from one end of the collet for receiving the blade.
When the collet 16 is compressed the opposing walls formed by slit
18 clamp down on the blade 14 and this provides one of the securing
forces on the blade. The retaining nut or member 20 is used to tighten
the collet and apply the compressive forces which allow the collet
to hold the blade in place. The collet fits in an opening in the
handle 22 and is secured by retaining member 20. Twisting the retaining
member compresses the collet 16 and closes longitudinal slit 18
so that the blade is held in place. The handle member has a neck
24 near the first end which is open and a middle section 26 and
a tapered portion 28 near the second end 31. It is not absolutely
required that the portion 28 be tapered, i.e. of a smaller diameter
than section 26. However, tapering this portion allows a portion
of the handle to be thicker for a better grip for holding the blade
while allowing some portion of the handle to be thinner so that
it can be used in combination with a wrench member, described below,
in order to remove a cap which fits over a normally closed end of
the wrench.
Handle Assembly-Wrench Combination
Referring to FIGS. 2 and 3 a combined wrench and protective shield
member 30 having an open end 36 and a closed end 37 is shown. FIG.
2 shows the wrench in operating engagement with the retaining member
of the handle assembly which is in place on the neck portion of
handle 22. The blade 14 held in place in the collet, is protectively
contained or shielded within the axial passage 44 of the larger
diameter portion 32 of the wrench 30. The blade is safely contained
within the enclosure by cover 46. However, the blade can be safely
loosened by wrench 30 for removal from handle 22 without exposing
medical personnel to a sharp blade. The ability to loosen the blade
or better secure it to the handle member without exposing the operator
to the risk of an infection is believed to be a significant advancement
in the art. A smaller cylinder portion 34 of the wrench body is
configured to be able to apply a twisting force to retaining member
20. In turn this imparts a force on collet 16 and, in particular,
compresses the longitudinal slits of the collet closer together
to hold the blade firmly in place. Turning the wrench in an opposite
direction loosens the retaining member 20 thereby allowing the
longitudinal slits to expand and release blade 14.
FIG. 3 shows the opening 36 attached to the smaller cylinder portion
34 in which the retaining member fits to pass the blade into the
axial passage of the wrench. At the second end 37 (FIG. 2) of the
wrench a removable insert or cap 38 can be removed in order to allow
cleaning of the axial passage 44 and the inside wall of cylindrical
portion 34 which is configured to turn the retaining member 20.
The cap is shown as a force-fit member, but it would be apparent
to one skilled in the art to create threads on the cap and wrench
member for allowing insertion and removal by a screwing action.
This is a significant advancement in the art because it is important
to clean any medical instrument which may have come into contact
with blood due to the danger of contamination.
FIGS. 4 and 5 show the wrench 30 from a different point of view
of that shown in FIG. 3. FIG. 4 is a top plan view of the wrench
where opening 36 can be clearly seen. Ridges 40 and valleys 42
which are disposed between the ridges, are used for mating up with
matching ridges 62 and valleys 64 (FIG. 1) on the retaining member
20 in order to twist the retaining member.
FIG. 5 shows a partial sectional view taken along sectional lines
5--5 of FIG. 4. In this view the cover 46 is partially removed to
reveal the axial passage 44 and the inner wall 45 of the smaller
cylindrical portion 32. In this view it will be appreciated that
the end 37 is sealed by removable insert 38 so that the blade is
not exposed. For safety's sake, it is important that the blade be
prevented from jamming against the insert. This may be accomplished
by shortening the length of the threaded portion of the smaller
cylinder or by lengthening the longitudinal axis of axial passage
44.
FIG. 6 shows handle 22 with tapered portion 28 inserted in the
axial passage of wrench 30 wherein end 31 is capable of pushing
removable insert 38 off of end 37 of the wrench so that the inside
of the wrench can be cleaned. The cleaning may be done in two steps,
first with a bottle brush and then placing the wrench member in
a sterilizing apparatus.
FIG. 7 shows an exploded view of the handle assembly 12 described
above with reference to FIG. 1. The handle 22 includes open end
33 for receiving the collet and opposite closed end 31. Between
the open end and the closed end is a neck 24 including a threaded
portion 56 shoulder 23 which is adjacent middle portion 26 and
tapered end portion 28 which is adjacent the closed end. The threads
mate up with corresponding threads 68 (FIG. 8) on the inside of
the retainer 20. The middle portion 26 is preferably thick enough
to allow a comfortable grip by an operator. The reduced portion
28 is preferred to be dimensioned to fit within the axial passage
of the wrench in order to pop the removable inset out.
The handle assembly includes a collet 16 that has a substantially
elongated body that is preferably conically shaped at each end.
The conically shaped body has a first longitudinal slit 18 extending
from one end of the collet to substantially the middle 54 of the
collet 16 forming a first pair of spaced opposed jaws. A second
longitudinal slit 48 extends from an opposite end of the collet
just past the middle portion 54 forming a second pair of spaced
opposed jaws.
Preferably, the length of the slits overlap. Additionally, the
slits should be offset at an angle from each other. In other words,
each slit is offset at a different angle from the longitudinal axis.
Preferably, each slit is offset at about ninety degrees from the
other.
In a preferred embodiment, the conical shape is further divisible
into two opposing cones sharing frustum sections through middle
portion 54. The first conical section 50 has a tip at first end
19 and the oppositely oriented second cone 52 also has a frustum
section in the middle 54 and has a somewhat truncated tip section
at the end of the collet 21.
It is not necessary that the collet be conical in shape; however,
the inventors have recognized that this is the best configuration
for achieving the invention's objectives. The collet is preferably
an elongated body having an axial passage from end 19 to end 21.
The longitudinal slit 18 extends from end 19 to about the middle
and receives the blade 14 into the axial passage of the collet.
The opposing jaw or wall assembly formed by the longitudinal slit
18 is compressible by the retaining member at open end 60 so that
the walls can be used to clamp or grip opposing sides of the blade.
A second jaw or wall assembly formed by longitudinal slit 48 extends
from the end 21 and is also compressible by the retaining member
and serves to allow clamping or gripping by the inner walls of the
collet of opposing edges of the blade. Thus the blade is gripped
in two directions to ensure that it does not slip or fall out.
The ability to grip the blade in two directions is a critical advancement
in the art which has not been accomplished by the prior art. It
is preferable to place the blade into the collet prior to tightening
the retaining member 20. Typically such blades, as blade 14 are
provided with protective sheathes over sharp portion 15 which can
be used by a human to grip the blade safely prior to placing it
in the collet. However, these sheathes are disposed of once the
blade is installed the first time, and subsequent removals are rendered
dangerous with prior art wrenches.
A shank portion 17 of blade 14 slips into longitudinal slit 18
through an axial passage in the collet body and through open end
21. Blade 14 and collet 16 enter the retaining member 20 through
open end 60. The retaining member is turned and its internal threads
secure it to threads 56. Open end 66 of the retaining member, when
installed on the assembly, extends past the threaded portion 56
into the neck portion 24 of the handle 22. Conveniently, the ridges
62 disposed on either side of valleys 64 can be used to turn the
retaining member between the fingers of an operator. This hand-tightening
operation is safe to perform the first time the blade is installed
but the inventors have recognized that it is unsafe to perform by
regular medical personnel once the sheath has been disposed and
therefore have provided the wrench member for the combination of
this invention. Once a retaining member including a collet and blade
is removed from the handle it can be left in the protective enclosure
of the wrench handle. The wrench member can then be moved to a special
area where special equipment such as pliers are available so that
specially trained personnel may process the contaminated blade.
Meanwhile, a new blade, collet, and retaining member can be installed
on the handle for use in surgery.
FIG. 8 is a partial sectional view showing a portion of handle
22 with the collet in place in the threaded portion of the neck
of the handle and the retaining member also in place. Blade 14 is
held in place in longitudinal slit 18 by the compressing force of
retaining member 20 as the retaining member's threads 68 engage
the threads 56. A hollow portion 29 in the neck begins at wall 43
and extends to end 33. It is partially filled up by the collet.
The collet has an axial passage which is composed of hollow portion
23 of the collet combined with the longitudinal slit 18.
FIG. 9 shows a partial sectional side view of the handle, including
middle portion 26 and neck 24 with the above-described threaded
portion for mating with the threaded portion of the retaining member
20. When the retaining member is tightened the longitudinal slit
48 allows the inner walls 78 of the collet at hollow portion 23
to be compressed and clamped down on edges 73 of the blade 14. Thus,
the blade is held in place by a securing compressive force on edges
73 as well as a securing compressive force in another direction
on opposing sides 70 (FIG. 8). The longitudinal slits 18 and 48
allow the collet to be elastically deformable in response to a compressive
force yielded by tightening the retaining member.
FIG. 10 shows a schematic representation of the compressive forces
yielded by the collet on the blade 14. A compressive force in direction
71a and 71b on sides 70 is exerted by the compression of longitudinal
slit 18. A compressive force in direction 72a and 72b on edges 73
is yielded when blade 14 is compressed by opposing jaws formed by
the slit 48 as a result of axial force by the retaining member.
Regarding composition materials, the inventors have determined
that the following choices are the best for achieving the invention's
objectives. The wrench is preferably made of a sterilizable plastic,
e.g. ultem. The collet is preferably made of stainless steel because
of the desirable elasticity of that metal. Empirical evidence has
shown that it is best to heat-treat the steel to obtain about 40-42
C-scale Rockwell hardness. The retaining member and handle are preferably
made of titanium because it is very strong but is also light-weight
and non-corrosive. The handle is preferably solid from end 31 to
neck 24 until it is necessary to create the hollow portion for receiving
the collet.
In view of the above description, it is possible that modifications
and improvements will occur to those skilled in the art which are
within the scope of the appended claims. Therefore, this invention
is not to be limited in any way except by the appended claims. |