Medical instrument for use in combination with endoscopes

• US 5,849,022 A
• Filed: 08/06/1997
• Issued: 12/15/1998
• Est. Priority Date: 07/29/1994
• Status: Expired due to Term

• Current Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Original Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Inventors: Shimizu, Toru, Sasaki, Katsumi, Sakashita, Kiyotoshi, Sugai, Toshiya, Iida, Koji, Kimura, Kenichi, Murakami, Eiji, Hashiguchi, Toshihiko, Kikuchi, Yasuhiko
• Primary Examiner(s): Thaler, Michael H.
• Application Number:
  US08/907,269
• Time in Patent Office: 496 Days
• Field of Search: 606/205, 606/206, 606/170, 606/171, 606/174, 606/51, 606/52, 606/207, 600/564
• US Class Current: 606/174
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 2017/0046 with a releasable handle; with handle and operating part separable for prosthetic joint-implanting tools A61F2/4603
• CPC Class Codes: A61B 2017/2931 with releasable head
• CPC Class Codes: A61B 2017/2934 arcuate shaped guiding means
• CPC Class Codes: A61B 2017/2936 Pins in guiding slots
• CPC Class Codes: A61B 2017/2945 Curved jaws
• CPC Class Codes: A61B 2018/1432 curved

Abstract

A medical instrument for use in combination with an endoscope having an operating shaft and a pair of tongs. The instrument has a drive mechanism provided between the operating shaft and the tongs, for opening and closing the tongs. The drive mechanism can apply an additional force to the tongs even after the tongs have closed completely.

Claims

1. A medical instrument comprising:

an insertion section to be inserted into a body cavity through an instrument-inserting channel of an endoscope;

a pair of treating members connected to a distal end of the insertion section;

an operation section connected to a proximal end of the insertion section for opening and closing the treating members;

an operating shaft extending through the insertion section, and wherein said operation section includes shaft-moving means for moving said operating shaft back and forth in said insertion section; and

drive means including a cam mechanism for opening and closing said treating members when said operating shaft is moved back and forth, and for applying an additional force to said treating members even after said treating members have come to abut on each other; and

wherein said cam mechanism comprises cam grooves and cam pins for moving along the cam grooves, respectively, said cam grooves being longer than is necessary to move said treating members between an open position and a closed position where said treating members abut on each other.

2. The medical instrument according to claim 1, wherein said insertion section has an outer sheath, wherein said drive means further includes a distal cover which supports said operating shaft such that said operating shaft is movable back and forth in an axial direction, and a support pin supporting said treating members, and wherein each of said treating members has a proximal end portion having an elongated support hole for receiving said support pin, and a cut-away portion between the proximal end portion of said treating members 10 and said outer sheath of said insertion section.

3. The medical instrument according to claim 1, wherein said drive means further includes a distal cover which supports said operating shaft such that said operating shaft is movable back and forth in an axial direction, S and a support pin supporting said treating members, and wherein each of said treating members has a proximal end portion having an elongated support hole for receiving said support pin, and a weak portion located closer to a proximal end of said treating members than the support hole.

4. The medical instrument according to claim 3, wherein each of said treating members includes a link arm from which a cam pin protrudes, and wherein said weak portion has a cross section which is taken along a plane perpendicular to an axis of said operating shaft and which has a narrowest part located between the cam pin and the support hole.

5. The medical instrument according to claim 1, wherein said drive means includes a distal cover which supports said operating shaft such that said operating shaft is movable back and forth in an axial direction, and a coupling member which is connected to a distal end of said operating shaft, said coupling member having a projection abutting on inner sides of both arms of said distal cover and said coupling member being capable of withstanding a moment of a couple generated from a reaction from a cam pin.

6. A medical instrument comprising:

an insertion section to be inserted into a body cavity through an instrument-inserting channel of an endoscope, said insertion section including a sheath unit;

a pair of openable and closable treating members connected to a distal end of the insertion section;

an operation section connected to a proximal end of the insertion section;

an operating shaft extending through the insertion 10 section, and wherein said operation section includes shaft-moving means for moving said operating shaft back and forth in said insertion section;

drive means, provided between said operating shaft and said treating members and including a cam mechanism, for opening and closing said treating members when said operating shaft moves back and forth in said insertion section, and for applying an additional force to said treating members even after said treating members have come to abut on each other;

a drive unit connecting said treating members to said drive means; and

unit-connecting means provided between said sheath unit of said insertion section and at least one of said drive unit and said operation section for removably connecting said sheath unit to at least one of the drive unit and said operation section; and

wherein said cam mechanism comprises cam grooves and cam pin for moving along the cam grooves, respectively, said cam grooves being longer than is necessary to move said treating members between an open position and a closed position where said treating members abut on each other.

7. The medical instrument according to claim 6, wherein said unit connecting means comprises:

an arm supported at at least one end thereof, said arm extending between said sheath unit and at least one of said drive unit and said operation section;

an engagement recess provided in one of said sheath unit and at least one of said drive unit and said operation section; and

an engagement projection protruding in a direction other than a direction in which said arm extends, said engagement projection being removably fitted in said engagement recess.

8. The medical instrument according to claim 7, wherein said unit-connecting means further comprises deforming-preventing means abutting on an inner side of said arm and preventing said arm from being deformed to extend inward.

9. The medical instrument according to claim 8, wherein said deforming-preventing means comprises a hollow cylinder secured to said operating shaft and having an outer diameter equal to an inner diameter of said arm.

10. The medical instrument according to claim 9, further comprising position-adjusting means for adjusting a position of said operating shaft, said position-adjusting means being provided at at least one of a junction with said coupling member and a junction with said hollow cylinder.

11. The medical instrument according to claim 10, wherein said position-adjusting means comprises a screw mechanism including a male screw and a female screw.

12. The medical instrument according to claim 6, wherein one of the units removably connected together by said unit-connecting means has a first positioning portion having a semi-circular cross section and extending in an axial direction of said operating shaft, and the other of said units has a second positioning portion for positioning the units with respect to a rotation direction of the units.

13. The medical instrument according to claim 12, wherein said operating shaft has a spherical portion at a proximal end, said operation section has a fixed handle and a movable handle rotatably coupled to the fixed handle, said movable handle having an engagement hole for receiving the spherical portion of said operating shaft, and said first and second positioning portions having a length at least equal to a distance between a position at which said spherical portion enters said engagement hole and a position at which said movable handle fully opens said treating members.

14. The medical instrument according to claim 13, wherein said movable handle has a groove formed in a portion contacting said fixed handle and a passage communicating with a bottom of said engagement hole.

15. The medical instrument according to claim 13, wherein said movable handle comprises a head in which said engagement hole is formed and which stands upright while said treating members are one of clamping an object and peeling an object from another object, and wherein said engagement hole extends at substantially right angles to an axis of said insertion section.

16. The medical instrument according to claim 13, wherein said treating members comprise a pair of scissors for cutting an object, and said movable handle comprises a head in which said engagement hole is formed and which stands upright while said treating members are clamping an object, and wherein said engagement hole extends at a substantially right angle to an axis of said insertion section.

17. The medical instrument according to claim 13, wherein said fixed handle has an electrode-connecting portion, and wherein a connecting portion of an electric cord to be connected to the electrode-connecting portion has a holder section large enough to cover an insulating cover mounted on said electrode-connecting portion.

18. The medical instrument according to claim 6, wherein said operating shaft comprises a super elasticity alloy.

19. The medical instrument according to claim 6, wherein:

said drive unit has a first positioning portion having a semi-circular cross section and extending in an axial direction of said operating shaft,

said sheath unit has a second positioning portion having a cross section of a shape corresponding to the first positioning portion,

said first and second positioning portions position the units removably connected together by said unit-connecting means with respect to a rotation direction of the units,

said operating shaft has a spherical portion at a proximal end,

said operation section has a fixed handle and a movable handle rotatably coupled to the fixed handle, said movable handle having an engagement hole for receiving the spherical portion of said operating shaft, and

further comprising an assembly-assisting mechanism having a length such that the spherical portion of said operation shaft remains entered in the engagement hole of said movable handle when a proximal end of said first positioning portion abuts on a distal end of said second positioning portion.

20. A medical instrument for use in combination with an endoscope, comprising:

an insertion section to be inserted into a body cavity;

a pair of treating members rotatably connected by a support shaft to a distal end of said insertion section;

an operation section connected to a proximal end of said insertion section for opening and closing said treating members;

an operating shaft extending through said insertion section, said operating shaft being movable back and forth when said operation section is operated; and

drive means including a cam mechanism for opening and closing said treating members in response to a linear motion of said operation shaft when said operation section is operated, and for applying an additional force to said treating members even after said treating members have come to abut on each other,

wherein said operating shaft is elastically deformed when said operation section is operated to open and close said treating members; and

wherein said cam mechanism comprises cam grooves and cam pins for moving along the cam grooves, respectively, said cam grooves being longer than is necessary to move said treating members between an open position and a closed position where said treating members abut on each other.

21. The medical instrument according to claim 20, wherein said operating shaft comprises an elastic material.

22. The medical instrument according to claim 21, wherein said elastic material comprises a super elasticity alloy.

23. The medical instrument according to claim 20, wherein said operating shaft includes means for enabling a movable handle of said operation section to rotate through an angle greater than is necessary to close said treating members.

24. A medical instrument comprising:

an insertion section to be inserted into a body cavity through an instrument-inserting channel of an endoscope;

a pair of treating members connected to a distal end of the insertion section;

an operation section connected to a proximal end of the insertion section for opening and closing the treating members;

an operating shaft extending through the insertion section, and wherein said operation section includes shaft-moving means for moving said operating shaft back and forth in said insertion section; and

drive means including a cam mechanism for opening and closing said treating members when said operating shaft is moved back and forth, and for applying an additional force to said treating members even after said treating members have come to abut on each other,

wherein said drive means includes a support pin supporting said treating members, and each of said treating members has a proximal end portion having an elongated support hole for receiving said support pin; and

wherein said cam mechanism comprises cam grooves and cam pins for moving along the cam grooves, respectively, said cam grooves being longer than is necessary to move said treating members between an open position and a closed position where said treating members abut on each other.