U.S. patent number 3,854,473 [Application Number 05/364,258] was granted by the patent office on 1974-12-17 for stilet for endoscopes.
This patent grant is currently assigned to Olympus Optical Co., Ltd.. Invention is credited to Kazumasa Matsuo.
United States Patent |
3,854,473 |
Matsuo |
December 17, 1974 |
STILET FOR ENDOSCOPES
Abstract
A stilet for endoscopes includes an elongated coil spring to be
inserted in the flexible tube of the endoscope. The coil spring may
be compressed or extended by operating a mechanism outside of the
human body so that the flexibilility of the coil spring and thus
the flexible tube may be adjusted.
Inventors: |
Matsuo; Kazumasa (Tokyo,
JA) |
Assignee: |
Olympus Optical Co., Ltd.
(Tokyo, JA)
|
Family
ID: |
23433716 |
Appl.
No.: |
05/364,258 |
Filed: |
May 29, 1973 |
Current U.S.
Class: |
600/104; 600/144;
128/207.14 |
Current CPC
Class: |
A61B
1/2736 (20130101); A61B 1/018 (20130101); A61B
1/31 (20130101) |
Current International
Class: |
A61B
1/018 (20060101); A61B 1/012 (20060101); A61B
1/31 (20060101); A61B 1/273 (20060101); A61b
001/06 (); A61b 001/26 () |
Field of
Search: |
;128/8,6,4,5 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Laudenslager; Lucie H.
Attorney, Agent or Firm: Flynn & Frishauf
Claims
What is claimed is:
1. A stilet for varying the flexibility of an endoscope
comprising:
a coil spring having a central axis, said coil spring being adapted
to be inserted in the flexible tube of an endoscope,
a retracting wire inserted through the coil spring substantially
along said central axis, one end of the wire being operatively
connected to one end of the coil spring, and
adjusting means provided on the other end of the coil spring and
coupled to the other end of the wire to selectively tighten said
wire relative to the coil spring to compress adjacent turns thereof
closer to each other to stiffen the coil spring, or to retract and
loosen the wire relative to the coil spring to render the spring
more flexible, thereby selectively adjusting the flexibility of the
coil spring and of the flexible endoscope tube in which the coil
spring is inserted.
2. A stilet according to claim 1 wherein said adjusting means
includes a cylindrical adjusting member in which said other end
portion of the retracting wire is inserted and which is coaxial
with the coil spring, a sliding ring mounted on the periphery of
said cylindrical adjusting member so as to be slidable along its
longitudinal direction and connected to said other end of the
retracting wire, and a keeping mechanism operatively coupled with
the sliding ring to maintain the sliding ring at the desired
position.
3. A stilet according to claim 2 wherein said cylindrical adjusting
member has at one end a connecting member to receive said other end
of said coil spring and at one side of the other end a slit
extending in a longitudinal direction of the adjusting cylindrical
member, and said sliding ring has a guide plate extending to the
internal bore of said cylindrical adjusting member through the
slit.
4. A stilet according to claim 3 wherein said keeping mechanism
includes a row of teeth formed on one side of said cylindrical
adjusting member near the connecting ring along the longitudinal
direction thereof and a lever pivotally mounted on the sliding ring
and having at least one tooth engageable with the teeth of said
cylindrical adjusting member.
5. A stillet according to claim 4 wherein said lever has a
plurality of teeth thereon which are engageable with the teeth of
said cylindrical adjusting member.
6. A stilet according to claim 5 wherein the lever further includes
an urging member for urging the lever so that in an normal
condition the teeth of the lever engage the teeth of the adjusting
cylindrical member, and a handle to release the engagement of the
teeth of the lever and adjusting cylindrical member against the
operation of the urging member.
7. A stilet according to claim 1 wherein the coil spring includes a
guide member coaxially attached to said one end thereof and having
a curved surface, said one end of said retracting wire being
connected to said guide member.
8. A stilet according to claim 7 wherein said curved surface of
said guide member is at the forward edge of said stilet.
9. A stilet according to claim 1 wherein said coil spring is
adapted to extend along the whole length of the flexible tube of
the endoscope.
Description
BACKGROUND OF THE INVENTION
This invention relates to a stilet to be inserted in an endoscope
for adjusting the flexibility of the endoscope to assist in smooth
insertion of the scope into the cavity of a human body.
In recent years, the development of an endoscope has been
remarkable in permitting the device to be inserted through the
mouth as far as the stomach, duodenum and the small intestine, and
through the anus as far as the rectum, sigmoid colon, descending
colon, transverse colon and the ascending colon, for medical
observation of these organs.
It is required than an endoscope operative for deep observation be
sufficiently flexible and bendable so that the forward end thereof
may smoothly reach a position of predetermined depth. It has
heretofore been difficult to insert the device deeply because of
the fact that it tends to be unnecessarily bent concentratedly at a
relatively shallow portion of the human body such as the stomach to
disturb advancement of the forward end of the device or because of
its insufficient overall available length.
In an attempt to obviate this defect, a device has been proposed in
which the flexibility of the flexible tube of the endoscope is
progressively varied in such a manner that the tube is made
relatively soft at its forward end and is made gradually harder at
portions closer to the operation section. The endoscope of the
arrangement in which the rigidity or flexibility of the tube is
predetermined does not assist to positively solve the above
problem. The defect may be eliminated if the flexibility of the
flexible tube is made adjustable, but with the prior art device,
the construction of the tube to make it adjustable becomes complex,
thereby resulting in a tube of an inconveniently increased
diameter.
SUMMARY OF THE INVENTION
Accordingly the object of the invention is to provide a stilet of
simple construction and capable of being externally operated to
optionally adjust the flexibility of a flexible tube of an
endoscope by being inserted into the endoscope prior to the
insertion of the device into the cavity of a human body.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional elevation of a stilet embodying this
invention;
FIG. 2 is a cross section taken along the line 2--2 in FIG. 1;
and
FIG. 3 is a schematic view illustrating an endoscope employing the
stilet of FIG. 1 as being in an operative inserted position.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
There will now be described a stilet according to the embodiment of
the present invention with reference to the drawings.
In FIG. 1, the stilet 10 includes an elongated coil spring 11 with
a small pitch or shot clearance between the adjacent turns, one end
of which is attached to the rear end of small diameter of a guide
member 12 whose forward end has a semispherical surface. The other
end of the spring 11 is received and connected to the forward end
of a connecting ring 14 with a central through bore 13. The
connecting ring 14 is attached to an adjusting cylinder 15 at its
rear end so that the central bore 13 of the former is coaxially
connected to the central bore of the latter. On the upper side of
the front half portion of the adjusting cylinder 15 there is formed
a row of triangular teeth 16 along the longitudinal direction
thereof. On the lower side of the rear half portion of the
adjusting cylinder 15 there is perforated a long slit 17 extending
along the longitudinal direction and communicating with the central
bore thereof. The triangular teeth 16 each may be in the shape of a
right-angled triangle with the hypotenuse and vertical side
respectively corresponding to the front and rear sides of the
tooth. A sliding ring 18 is fitted on the periphery of the
adjusting cylinder 15 so as to slide along the rear half portion
thereof. From the upper outer side of the ring 18 there is radially
extended a projection 20 with its forked top portion forming a
bearing 19. On the lower inner side of the ring 18 there is fixed a
supporting plate 21 (see FIG. 2) extending into the central bore
through the slit 17 of the adjusting cylinder 15. By means of this
supporting plate 21, the sliding ring 18 may be supported on the
adjusting cylinder to be slidable therealong without rotation of
the sliding ring 18. A retracting wire 22 is inserted through the
central bores of the coil spring 11, connecting member 14 and
adjusting ring which are arranged in a coaxial relationship. The
wire 22 is connected to the rear end of the guide member 12 and the
forward side of the supporting plate 21 at its both ends to be
stretched therebetween.
A lever 26 is rockably supported on the bearing 19 of the
projection 20 by means of a pin 23. On the forward lower side of
the lever 26 there are formed a plurality of teeth 24 engageable
with the teeth 16 of the adjusting cylinder 15. The rear portion of
the lever constitutes a handle 25. Between the sliding ring 18 and
lever 26 there is connected a wire spring 27 so that, in the normal
condition, the lever 26 is urged in the rotating direction of an
arrow a to allow the teeth of the lever 26 to engage the teeth of
the adjusting cylinder 15 thereby preventing the sliding of the
sliding ring 18 in the backward direction by the coil spring
11.
With the stilet constructed above, when the sliding ring 18 is slid
against the adjusting cylinder 15, so that the teeth 24 of the
lever 26 pivoted on the sliding ring 18 are engaged with the
extremely forward portion of the row of teeth, the retracting wire
22 takes the most loose condition in which the coil spring 11 is
most flexible. In this situation, as the sliding ring 18 is moved
rearwards along the adjusting cylinder 15, the clearance between
the adjacent turns of coil spring 11 is gradually made shorter,
that is the coil spring is compressed to decrease its flexibility.
When the desired flexibility is obtained, the ring 18 is stopped,
so that its flexibility is maintained due to the engagement of the
teeth of the lever 26 and adjusting cylinder 15. Alternatively, if
it is desired to increase the flexibility of the coil spring 11,
the lever 26 is rocked by operating the handle 25 to release the
engagement of the teeth 16 and 24 so that the sliding ring 18 may
be retracted forwards by the coil spring 11.
In the using of the stilet, the coil spring of the stilet is
inserted into the flexible tube 30 of an endoscope from its forward
end, thereby being located in the flexible tube in a substantially
coaxial relationship therewith as shown in FIG. 3. Then, the
endoscope is inserted into the deep portion of the cavity of the
human body while the flexibility of the coil spring and thus the
flexible tube 30 is adjusted by operating the lever outside the
human body. Accordingly, the insertion of the flexible tube of the
endoscope whose flexibility is adjusted as the endoscope is deeply
inserted prevents the flexible tube from the unnecessarily
concentrated bending in a cavity located on the way to the observed
portion.
* * * * *