U.S. patent number 3,736,919 [Application Number 05/179,929] was granted by the patent office on 1973-06-05 for speculum latching mechanism.
This patent grant is currently assigned to Medspecs, Inc.. Invention is credited to John Cotey.
United States Patent |
3,736,919 |
Cotey |
June 5, 1973 |
SPECULUM LATCHING MECHANISM
Abstract
A latching mechanism is provided for a speculum. The speculum
itself is formed of a stiffly flexible plastic material whereby two
blade-like members are joined along one edge by a hinge which
integrally connects the two blades together for pivotal movement
between open and closed positions. The latching mechanism comprises
interlocking, teeth-like protuberances formed integrally on the
interior surfaces of the blades contiguous to the blade edges.
These protuberances are interleaved such that they frictionally
engage each other thereby to maintain the relative open or closed
position of the blades. The tips of the engaging surfaces may have
a raised pad to increase the frictional contact and yet maintain
constant loading on blade pivotal movement.
Inventors: |
Cotey; John (Haddonfield,
NJ) |
Assignee: |
Medspecs, Inc. (Frederick,
MD)
|
Family
ID: |
22658568 |
Appl.
No.: |
05/179,929 |
Filed: |
September 13, 1971 |
Current U.S.
Class: |
600/225;
600/220 |
Current CPC
Class: |
A61B
1/32 (20130101) |
Current International
Class: |
A61B
1/32 (20060101); A61b 001/30 (); A61b 001/32 () |
Field of
Search: |
;16/140,142,150,DIG.13
;128/17,18,19,20,242,243,244,341,342,345 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Pace; Channing L.
Claims
What is claimed is:
1. In a speculum which facilitates the examination of certain body
passages having first and second members each having an elongated
blade with a convex outer surface, a concave inner surface, an
elongated edge, and a handle integral therewith, and hinge means
connecting said blades together on an axis substantially coaxial
and coextensive with at least a portion of said elongated edge for
pivotal movement of said members at said hinge means between closed
and open positions, thereby to facilitate the opening of a body
passage to viewing and examination, the improvement which
includes:
spaced opposing, tooth-like protuberances one on the inner surfaces
of respective ones of said blades adapted to frictionally engage
each other during pivotal movement of said blades about said hinge
means, thereby to maintain the relative open positions of said
blades.
2. A speculum according to claim 1 wherein:
said protuberances are positioned contiguous said blade edges
thereby to facilitate the viewing of said body passages, and
at least one of said frictionally engaging protuberances has a
laterally positioned pad thereon adapted to engage the other
protuberance with a substantially constant frictional loading.
3. A speculum according to claim 1 wherein said speculum is plastic
and said hinge means and said members are integral.
4. A speculum according to claim 3 wherein said protuberances are
plural, planar, perpendicular to said axis and positioned
relatively on said respective blades to interleave with an
interference fit.
5. A speculum according to claim 4 wherein the thickness of said
protuberances is less than the spacing between opposing pairs of
protuberances, and the tip portion of at least one of said
protuberances has formed thereon a pad which together with the
thickness of the protuberance exceeds the spacing between said
opposing protuberances, thereby to achieve an interference fit and
relatively constant frictional torque resisting pivotal movement of
said blades.
Description
BACKGROUND OF THE INVENTION
This invention relates to a speculum and, more particularly, to a
speculum having a latching member which is economical to produce
and yet performs effectively.
There is on file in the Patent Office an application Ser. No.
46,725, filed June 16, 1970, entitled "Speculum" by Jean R.
Poirier, now abandoned, in favor of a continuation-in-part
application Ser. No. 171,187 filed Aug. 12, 1971. There is
described in the said Poirier application a speculum which finds
extensive use particularly in the field of gynecology. In this
field and others it is often desirable and necessary for the doctor
to examine both visually and with instruments the interior of
certain body passages. In the case of cancer of the reproductive
organs, for example, 95 percent of all cancer occurs at the cervix.
One of the tests used for the early detection of such cancer is the
so-called "Pap Test" which requires that a vaginal smear be made.
To effect this test, the physician must open the vaginal passage or
vault in order to obtain visual access to the cervix.
For this purpose, the physician typically uses one of the many
vaginal speculums that are available today. Most of these speculums
are made of metal and must be washed and sterilized after each use.
Due to excessive vaginal discharge, particularly in women suffering
from an infection, these existing instruments are difficult if not
impossible to thoroughly clean. Particles often remain attached to
the instrument even after washing, cleaning and sterilization. This
can leave a doubt in the mind of the doctor and his staff as to
whether or not they are, in fact, reinfecting the woman under
examination. Further, most presently available speculums open with
a jaw-like action which reduces the usefulness of the speculum.
Such speculums render episiotomy repair an extremely difficult task
in that the hinge portion is often in the precise area where
stitching is required and tend to impair both visual and manual
access.
The speculum described in the said Poirier application overcomes
many of these difficulties by providing a speculum having a pair of
elongated blades which are hinged along one elongated edge. In a
preferred embodiment the speculum is made of plastic and is an
integral unit with a so-called "living hinge."
When this speculum is used particularly in surgical repair of the
episiotomy operation following child birth, the speculum should be
securely lockable in a given open position such that the physician
has both hands free to perform the necessary stitching. Further,
the locking mechanism which facilitates this operation should be
relatively simple and easy to operate and yet not impede the vision
of the surgeon or obstetrician utilizing the instrument. Various
locking mechanisms were described in the said Poirier application
and all of these for the most part perform satisfactorily. On the
other hand, these locking mechanisms do suffer from the slight
disadvantage that they are somewhat difficult to operate and in
some cases significiantly add to the cost of the speculum.
It is, accordingly, an object of this invention to provide a
relatively simple, easy to use locking mechanism for a side opening
speculum.
Another object of this invention is to provide an improved low cost
speculum having a locking mechanism that is integrally formed with
the speculum itself.
BRIEF DESCRIPTION OF THE INVENTION
The latching mechanism for a speculum constructed in accordance
with a preferred embodiment of this invention is formed integrally
with the speculum itself. The speculum includes first and second
members. Each member includes an elongated blade with a convex
outer surface, a concave inner surface and a handle. The blade
portions are integrally connected along one edge for pivotal
movement. Preferably the members themselves are formed of a stiffly
flexible plastic and the hinge means is formed by providing a
relatively thin thickness dimension in the plastic material, i.e.,
the material is grooved so that the two blades may flex along this
thin dimension or groove.
The latching mechanism is formed integrally with each blade and
includes opposing teeth-like, interlocking protuberances on the
inner surface of each blade adapted to frictionally engage each
other thereby to maintain the relative positions of the blades.
Preferably these protuberances are positioned contiguous to the
blade pivot edges thereby to not impede the view of the surgeon. In
a preferred embodiment, the end portion of the faces of the
protuberances may have raised pads to increase the frictional
contact between the opposing tooth-like protuberances and yet,
because the area of contact remains essentially constant, blade
loading also remains essentially constant.
BRIEF DESCRIPTION OF THE DRAWING
The novel features that are considered characteristic of this
invention are set forth with particularity in the appended claims.
The invention itself, however, both as to its organization and
method of operation, as well as additional objects and advantages
thereof will be best understood from the following description when
read in connection with the accompanying drawings, in which:
FIG. 1 is a side elevation view of a speculum of the type described
in the said Poirier application having a locking mechanism
constructed in accordance with this invention;
FIG. 2 is a top plan view of the speculum illustrated in FIG. 1
particularly illustrating the radially outwardly flared
handles;
FIG. 3 is a front end view of the speculum illustrated in FIG.
1;
FIG. 4 is a back end view of the speculum shown in FIG. 1 which
clearly depicts the locking mechanism of this invention;
FIG. 5 is a bottom view of the speculum illustrated in FIG. 1 but
with the speculum now presented in its open position;
FIG. 6 is a back end view of the speculum illustrated in FIG.
5;
FIG. 7 is a cross-sectional view of the locking mechanism taken
along the section lines 7--7;
FIG. 8 is a partial blown-up view of the locking mechanism as seen
in FIG. 7;
FIG. 9 is a cross-sectional view of the speculum illustrated in
FIG. 1 taken along the section line 9--9; and
FIG. 10 is a partial cross-sectional view taken along the section
line 10--10 of FIG. 9 illustrating the locking mechanism in a
closed position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As is described in the said Poirier application, the speculum
illustrated in FIGS. 1-10 has a pair of mating side members 10 and
12. Each member includes a blade portion 18 and a handle portion
20. Each of the members 10 and 12 is generally hollow and
shell-like to provide a convex exterior of the required shape for
the purpose intended and conversely, a generally concave interior
to permit visual as well as manual access thereto. The two side
members 10 and 12 are joined together by a hinge means 14 at one
edge which hinge means will hereinafter be referred to as the axis
of the speculum.
Each of the side members 10 and 12 is formed of integrally
connected parts -- a blade portion 18 and a handle portion 20 -- as
noted. In the preferred embodiment, the two side members 10 and 12
preferably are formed of a single piece of stiffly, flexible
plastic material such as polyamid sold under the trade name
"NYLON," polytetrafluoroethylene sold under the trademark "TEFLON"
or alternatively, a polypropylene plastic may be used or as still
another alternative a high density polyethylene plastic may be
used.
The hinge means 14 is of the same material as the two side members
10 and 12. To form the hinge means, the material joining the two
side members 10 and 12 along their upper longitudinal edge is
merely molded or fabricated to have a relatively thin wall
thickness dimension or groove as seen at 14 (FIG. 3) such that the
plastic, which is stiffly flexible to begin with, can more easily
flex at this point. A hinge of this type is capable of many
flexures over an extended period of time without the plastic
material fatiguing or breaking. The hinge 14 extends only along
that portion of the adjoining edges of the side members 10 and 12
which lie in a straight line and constitute the axis of the
speculum. Otherwise the flexure of the two pieces would be
inhibited. It is thus seen that the hinge 14 permits the two side
members 10 and 12 to flex or pivot about the common longitudinal
edge of the blade portions 18 such that the lower longitudinal
blade edges of the speculum may be pivoted open, as may be seen
most clearly in FIG. 5, to permit visual and manual access to the
interior of a body passage.
In accordance with a preferred embodiment of this invention,
latching mechanism 22 is provided which permits the speculum to be
pivoted about its axis between an open and closed position and
remain in any desired open or closed position. This latching
mechanism 22 is particularly useful for those speculums designed
for surgical usage, i.e., episiotomies and the like. The locking
mechanism 22 includes interleaved, tooth-like sets of protuberances
24 and 26 (FIG. 5) which are formed respectively on the inner
concave surface 27 of the speculum blades in a region contiguous to
the hinge 14. These protuberances are formed of the same plastic
material as the speculum itself and preferably are molded
integrally therewith as noted. By way of shape, they are formed to
be planar, in parallel relationship to each other in planes
perpendicular the axis of the hinge 14. The respective sets of
protuberances 24 and 26 are offset such that when the speculum is
closed they tend to interleave with each other. In this manner one
protuberance of the set 26 enters the space or gap between two
adjacent protuberances of the other set 24. In the embodiment
illustrated there are only two protuberances in the set 24 which
are positioned to interlock or interleave in the spaces between the
set of three protuberances 26. Braces 28 are molded integrally with
the outer two of the protuberances of set 26 to prevent their
excessive flexure and to maintain close frictional contact between
the interleaving protuberances. The thickness of each protuberance
24 is preferably greater than the spacing between the other set of
protuberances and conversely the spacing between any pair of
protuberances is less than the thickness of the mating interleaving
protuberances of the other set. Stated otherwise, there should be
an interference fit between the interlocking protuberances.
In a preferred embodiment of the invention, the design of the
interlocking sets of protuberances is modified as illustrated to
permit essentially a constant frictional load resisting pivotal
movement of the blades. To achieve this, the thickness of the
several protuberances of each set is reduced to less than the
spacing of the protuberances in the opposing set. At the tip
portion of one of the sets of protuberances 26, there is formed a
pad 30 on the interior sides that are adapted to engage the other
set of interlocking protuberances 24. The thickness of the pad is
such that the interlocking protuberances achieve an interference
fit. The pads 30 are proportioned in an arcuate fashion which arc
is generally perpendicular to the path of movement of the tip
portion of the protuberances. The arcuate pads 30 have a constant
width measured along their path of pivotal movement to maintain the
constant frictional loading. The point of application of the
frictional resistance is at a relatively constant radial distance
from the pivot point or axis of the hinge 14, hence, the frictional
loading resisting movement of the blades remains relatively
constant regardless of blade position.
Whereas two protuberances are illustrated as being in the first set
24 and three in the second set 26, it is to be understood that this
number could be one and two, three and four, or any other
combination so long as the braced set exceeds by one the number or
protuberances in the unbraced set. Also, a single protuberance
could be placed on each blade in an interfering relation, but this
is not preferred. Further, the number and configuration of the pads
30 may be varied but that illustrated is preferred for the reasons
enumerated. In fact, as noted, the pads 30 need not be used at all
and the protuberances are formed with an interfering fit.
It may be seen in the drawing that the handles 20 are flared
outwardly to permit easy manipulation by the user. Immediately
contiguous to the handle, the blades are recessed or formed to have
a reduced radial dimension as seen at 122. This is a portion of the
speculum that when in use is normally in the region of the lip of
the vagina or other body passage. This recess 122 decreases the
strain on the lip portion and facilitates such surgical stitching
as may be required. Further out along the blade portion 18, the
radial dimensions of the two blades are increased as seen at 124,
although the region 126 is relatively planar, for the purpose of
providing greater total movement to the speculum blades for a given
arcuate pivot action of the speculum handles. This provides a wider
speculum opening and better access to the interior of the body
passage. The region 125 (FIG. 4) also is flared outwardly at the
rear portion to avoid interference with the region to be stitched
and to further insure that the speculum remains in position while
in use. The front end portion of the blades is somewhat bulbous
when they are in the closed position, i.e., the convexity of the
blades increases as a function of the distance from the handles.
This facilitates the speculum remaining in position within the
vagina or other body passage without the normal tendency for it to
be expelled by the normal contractions of the vaginal muscles.
The blades are generally planar in the vicinity of the hinge means
but are rounded back inwardly as a function of the radial distance
from the hinge 14 as seen at 128 (FIG. 3) such that the speculum
blades when viewed from the front end position form a generally
triangular silhouette of the speculum blades is relatively planar
and permits the greatest access to the body cavity possible.
There has thus been described an improved speculum having a unique
latching mechanism that permits low cost manufacture and positive
loading against speculum movement.
It is obvious that many embodiments may be made of this inventive
concept, and that many modifications may be made in the embodiments
hereinbefore described. Therefore, it is to be understood that all
descriptive material herein is to be interpreted merely as
illustrative, exemplary, and not in a limited sense. It is intended
that various modifications which might readily suggest themselves
to those skilled in the art be covered by the following claims, as
far as the prior art permits.
* * * * *