Endoscope cap and endoscope

To provide an endoscope cap includes: a cover having a cylindrical shape with a bottom; a pedestal; and an elevator rotatably supported by the pedestal. The pedestal includes: a base; a support wall, rising from an edge of the base, and extending in an axial direction of the cover to support the elevator; a distal tip wall extending from a distal tip of the support wall in the same direction as the base; a bottom fixing protrusion protruding from the distal tip wall in a direction opposite to the support wall; and a lateral face fixing protrusion protruding from the base in a direction opposite to the support wall. The cover includes: a first fixing hole into which the bottom fixing protrusion is inserted, being disposed in the bottom; and a second fixing hole into which the lateral face fixing protrusion is inserted, being disposed in a lateral face.

TECHNICAL FIELD

The present invention relates to an endoscope cap and an endoscope.

BACKGROUND ART

A known endoscope includes an elevator at a distal tip of a channel passing through the inside of an insertion portion. The elevator is used to curve a treatment tool or the like inserted through the channel and to guide the treatment tool in a desired direction.

There has been proposed an endoscope cap provided with an elevator which is mounted on a distal tip of an endoscope before endoscopic examination and dismounted after the endoscopic examination (Patent Literature 1). Since the complicated structure around the elevator can be dismounted from the endoscope, it is possible to clean the endoscope easily.

CITATION LIST

Patent Literature

Patent Literature 1: WO 2018/070515 A

SUMMARY OF INVENTION

Technical Problem

The endoscope cap disclosed in Patent Literature 1 has a three-body structure: a cover, an elevator, and a pedestal. An elevator shaft disposed in the elevator is inserted into an elevator mounting hole disposed in the pedestal, thereby rotatably supporting the elevator. The pedestal that supports the elevator is fixed to a pedestal groove disposed in an inner surface of the cover.

Endoscope caps are desirably so-called “single-use” caps. Single-use endoscope caps to be supplied to medical institutions are packaged individually. Compared with endoscopes well known as precision instruments, endoscope caps are subjected to impacts during transportation and storage.

It is not possible to use an endoscope cap having a cover and a pedestal come off due to an impact. The pedestal and the cover should be mounted again or another endoscope cap should be prepared, which puts a burden on a user. Similarly, in mounting an endoscope cap on an endoscope, when a cover and a pedestal come off the endoscope cap, a user bears a burden.

A single-use endoscope cap is dismounted from an endoscope after the end of a case analysis. During the dismounting, when a cover and a pedestal come off, small components such as the pedestal may scatter. The scattering of a component to which a body fluid is attached imposes a burden on a user. For example, the user is required to search for the scattered component and disinfect the place where the scattered component has fallen.

In an aspect of the invention, an object is to provide an endoscope cap and the like including a cover and a pedestal that hardly come off.

Solution to Problem

An endoscope cap detachably attached to an insertion portion of an endoscope, the endoscope cap including: a cover having a cylindrical shape with a bottom, and being detachably attached to a distal tip of the insertion portion from an opening end portion; a pedestal held inside the cover; and an elevator rotatably supported by the pedestal, in which the pedestal includes: a base having a tabular shape, being disposed in an inner surface of a cylindrical portion of the cover; a support wall having a tabular shape, rising from an edge of the base, and extending in an axial direction of the cover to support the elevator; a distal tip wall extending from a distal tip of the support wall in the same direction as the base; a bottom fixing protrusion protruding from the distal tip wall in a direction opposite to the support wall; and a lateral face fixing protrusion protruding from the base in a direction opposite to the support wall, and the cover includes: a first fixing hole into which the bottom fixing protrusion is inserted, the first fixing hole being disposed in the bottom; and a second fixing hole into which the lateral face fixing protrusion is inserted, the second fixing hole being disposed in a lateral face.

Advantageous Effects of Invention

An aspect of the invention provides an endoscope cap and the like including a cover and a pedestal that hardly come off.

DESCRIPTION OF EMBODIMENTS

First Embodiment

FIG.1is an exterior view of an endoscope10. The endoscope10of this embodiment is a flexible scope for an upper gastrointestinal tract. The endoscope10includes an operation unit20and an insertion portion30. The operation unit20includes an elevation control lever21, a channel inlet22, and a bending knob23. The operation unit20is connected to, for example, a video processor, a light source device, and a display device (not illustrated).

The insertion portion30is long and has one end connected to the operation unit20. The insertion portion30includes a soft portion12, a bending section13, and an endoscope cap50in this order from the operation unit20. The soft portion12is long. The bending section13bends according to an operation of the bending knob23. The endoscope cap50covers a hard distal tip31(seeFIG.2) continuous with the bending section13.

In the endoscope10of this embodiment, the endoscope cap50can be detachably attached to the distal tip31. The endoscope cap50includes a cover52as an exterior member and an elevator80(seeFIG.2). The configuration of the endoscope cap50will be described later in detail.

Hereinafter, the longitudinal direction of the insertion portion30is referred to as “insertion direction”. Similarly, the side closer to the operation unit20along the insertion direction is referred to as “the operation unit side”, and the side away from the operation unit20is referred to as “the distal tip side”. For each component, the expressions “the operation unit side” and “the distal tip side” are used according to the direction in which each component is mounted on the endoscope10.

FIG.2is a perspective view of a distal tip of the insertion portion30.FIG.3is a view for describing a state where a treatment tool distal tip41protrudes from the distal tip of the insertion portion30. The configuration of the endoscope10according to this embodiment will be described with reference toFIGS.1to3.

The distal tip31disposed at a distal tip of the bending section13includes an observation window36and a lighting window37aligned on one side along the insertion direction. The lighting window37is disposed closer to the distal tip side than the observation window36. On the opposite side or on the operation unit side, the distal tip31includes a channel outlet35. A raiser83is disposed closer to the distal tip side than the channel outlet35. The cover52covering the distal tip31has a part provided with a substantially rectangular window53. The part corresponds to the observation window36, the lighting window37, and the raiser83. A side of the window53on the operation unit side is formed into a step. That is, a side of a part including the raiser83is closer to the operation unit side, and a side of a part including the observation window36is closer to the distal tip side.

The lighting window37radiates illumination light emitted from the light source device (not illustrated). It is possible to optically observe a range irradiated with the illumination light through the observation window36. The endoscope10of this embodiment is what is called a side viewing endoscope in which the viewing direction that allows optical observation intersects the insertion direction. The endoscope10may be a forward oblique viewing endoscope in which the viewing direction is slightly tilted toward the distal tip side. Alternatively, the endoscope10may be a backward oblique viewing endoscope in which the viewing direction is slightly tilted toward the operation unit side.

The channel inlet22and the channel outlet35are connected by a channel34passing through the inside of the soft portion12and the bending section13. A treatment tool40is inserted into the channel inlet22from the treatment tool distal tip41, thereby protruding the treatment tool distal tip41from the channel outlet35.

The treatment tool distal tip41protrudes while gently curving on the raiser83as indicated by the solid line inFIG.3. When a user operates the elevation control lever21, a lever60(seeFIG.7) moves as will be described later, and the elevator80moves in conjunction with the lever60as indicated by the arrow inFIG.1. The movement of the elevator80causes the treatment tool distal tip41on the elevator80to bend toward the operation unit20as indicated by the arrows and dash-dot-dot lines inFIGS.1and3. The movement of the treatment tool distal tip41is captured by an image sensor or the like (not illustrated) through the observation window36and shown on the display device (not illustrated).

The treatment tool40is an instrument used for treatment such as a high-frequency knife, a forceps, and a contrast tube. The instrument to be inserted into the channel34is not limited to one used for treatment. For example, an instrument used for observation such as an ultrasonic probe and a microscopic endoscope may be inserted into the channel34. Hereinafter, the instrument used for observation is also referred to as the treatment tool40.

The movement of the elevator80as described above may hereinafter be expressed as “the elevator80rises”. When the treatment tool distal tip41is bent due to a push from the raised elevator80, such an action is expressed as “the treatment tool40rises”. A user operates the elevation control lever21to adjust the level of the rise of the treatment tool40.

FIG.4is a front view of the distal tip of the insertion portion30. The cover52has a cylindrical shape with a bottom, having an opening end portion56at one end. The cover52includes a sign display54between the window53and the opening end portion56. For example, a model number of the endoscope cap50is shown on the sign display54. In this embodiment, the cover52is manufactured by injection molding, and the model number of the sign display54is formed during the molding of the cover52.

Note that, for example, laser marking may be employed to write characters or barcodes on the sign display54. In this case, for example, a lot number or a serial number can be individually shown on the cover52.

FIG.5is a front view for describing a state before the endoscope cap50is mounted on the distal tip of the insertion portion30. A user of the endoscope10holds the bending section13with one hand and pinches the cover52with two fingers of the other hand. Opposing the endoscope cap50and the distal tip31to each other, the user pushes the endoscope cap50to mount the endoscope cap50on the insertion portion30.

On completion of endoscopic examination, the user holds the bending section13with one hand and presses the right and left lateral faces of the cover52inFIG.5with two fingers of the other hand to deform the cover52slightly. The user pulls the cover52toward the distal tip side, thereby dismounting the endoscope cap50from the distal tip of the insertion portion30.

FIG.6is a perspective view of the distal tip of the insertion portion30before mounting the endoscope cap50. The configuration of the distal tip of the insertion portion30will be described with reference toFIGS.5and6. The distal tip31has a substantially columnar shape and is divided into an optical housing portion33and a lever chamber69by a groove disposed from the distal tip side toward the operation unit side at a position deviated from the center. The channel outlet35is open at a bottom of the groove.

A part of the periphery of the distal tip31is cut into a flat shape to form a first flat surface321. On a part of the first flat surface321, a third engagement portion29is disposed along the bottom of the groove that separates the optical housing portion33from the lever chamber69. The third engagement portion29is an oval recess.

The observation window36and the lighting window37are disposed in the first flat surface321on the side closer to the optical housing portion33. The operation unit side of the observation window36is provided with a nozzle38that sprays water and air to the observation window36to clean the observation window36. On the outer side of the optical housing portion33, a part of the periphery of the distal tip31is cut to form a second flat surface322and a third flat surface323. The second flat surface322and the third flat surface323are continuous at an angle.

The lever chamber69is hollow and covered with a rectangular thin lever chamber lid67along the periphery of the distal tip31. The lever chamber lid67is fixed at four corners by lid screws66. The lever chamber69includes a support wall68on the side closer to the optical housing portion33.

From the support wall68, an elevator connection portion61protrudes toward the optical housing portion33. The elevator connection portion61is a shaft having a rectangular cross section. As illustrated inFIGS.5and6, while the endoscope cap50is dismounted, the elevator connection portion61is exposed on the surface of the distal tip31.

FIG.7is a perspective view of the distal tip of the insertion portion30from which the endoscope cap50and the lever chamber lid67are dismounted. The lever60is disposed inside the lever chamber69. The lever60includes a wire anchor65at one end and the elevator connection portion61at the other end via a rotatable connection portion64. The lever60is rotatably supported by a hole disposed in the support wall68between the rotatable connection portion64and the elevator connection portion61. The term “rotatable” signifies a rotational motion within a predetermined angle range.

The wire anchor65is connected to an end portion of an elevation wire24. The elevation wire24is connected to the elevation control lever21through the insertion portion30(seeFIG.1). More specifically, the elevation wire24is inserted through a guide pipe (not illustrated) having an inner diameter slightly larger than an outer diameter of the elevation wire24. The guide pipe (not illustrated) passes through the insertion portion30in the longitudinal direction. Therefore, a distal tip of the elevation wire24moves back and forth in conjunction with the operation of the elevation control lever21. The elevation wire24is remotely operated by the elevation control lever21.

When a user operates the elevation control lever21in a direction indicated by the arrow inFIG.1, the distal tip of the elevation wire24connected to the elevation control lever21is pulled toward the operation unit side. The lever60is pulled by the elevation wire24and rotates.

FIG.8is a perspective view of the endoscope cap50as seen from the side where the endoscope cap50is to be mounted on the endoscope10.FIG.9is a view of the endoscope cap50as seen from the side where the endoscope cap50is to be mounted on the endoscope10.FIG.10is a cross-sectional view of the endoscope cap50taken along line X-X ofFIG.9.FIG.11is a cross-sectional view of the endoscope cap50taken along line XI-XI ofFIG.9.FIG.12is a cross-sectional view of the endoscope cap50taken along line XII-XII ofFIG.9.

As described above, the endoscope cap50includes the cover52and the elevator80. The elevator80is rotatably mounted on a pedestal70. The cover52includes the window53in the cylindrical portion. At one place on the periphery of the cover52, the window53is opened over almost the entire length. The pedestal70is fixed to an inner surface facing the window53.

As illustrated inFIG.11, a lateral face fixing protrusion74protruding from one end of the pedestal70penetrates a second fixing hole59penetrating the lateral face of the cover52. The configurations of the cover52and the pedestal70will be described later in detail.

FIG.13is a perspective view of the elevator80.FIG.14is a front view of the elevator80.FIG.15is a view of the elevator80as seen from the direction of A-arrow inFIG.14.FIG.16is a cross-sectional view of the elevator80taken along line XVI-XVI ofFIG.14.FIG.17is a view of the elevator80as seen from the direction of B-arrow inFIG.14. The configuration of the elevator80will be described with reference toFIGS.13to17.

The elevator80includes a columnar elevator shaft82and the raiser83protruding from one end face of the elevator shaft82substantially perpendicularly to the axial direction of the elevator shaft82. The raiser83has a substantially L shape including a second raiser832and a first raiser831in this order from the base end.

The second raiser832is in contact with the elevator shaft82and has a width substantially equal to a diameter of the elevator shaft82. The first raiser831is connected to one end portion of the second raiser832at an angle. The first raiser831includes a spoon-shaped recess84in an inner surface of the L shape.

A lever connection portion81is disposed at the other end portion of the second raiser832. The lever connection portion81is a U-shaped groove, opened toward the end portion of the second raiser832. One edge of the lever connection portion81is covered with an end portion of the elevator shaft82. In the second raiser832, a part closer to the elevator shaft82is partially provided with a tabular flange85. The flange85protrudes toward the outside of the L-shaped elevator80.

The lever connection portion81sandwiches the central axis of the elevator shaft82as indicated by the dash line inFIG.15. A lateral face of the flange85has a substantially semi-circular columnar shape substantially coaxial with the elevator shaft82.

FIG.18is a perspective view of the pedestal70.FIG.19is a front view of the pedestal70.FIG.20is a view of the pedestal70as seen from the direction of C-arrow inFIG.19.FIG.21is a view of the pedestal70as seen from the direction of D-arrow inFIG.19. The configuration of the pedestal70will be described with reference toFIGS.18to21.

The pedestal70includes a tabular base95having a rectangular shape and a tabular first wall77having a substantially rectangular shape. The first wall77rises from an edge on one of the long sides of the base95and extends along the longitudinal direction of the base95. The first wall77is an example of a support wall of this embodiment.

Furthermore, in parallel with the first wall77, a tabular second wall78having a substantially stepped shape with three tiers rises from the base95. The top tier of the second wall78has an end portion to which a rectangular tabular third wall79that straddles the first wall77and the second wall78is connected. The third wall79is an example of a distal tip wall of this embodiment.

The third wall79is provided with a first fixing protrusion73on a surface opposite to the first wall77. The first fixing protrusion73includes a slit. The first fixing protrusion73has an end portion provided with a slightly thicker lock. The first fixing protrusion73is an example of a bottom fixing protrusion of this embodiment.

In the pedestal70, the side on which the first fixing protrusion73protrudes is the distal tip side, and the opposite side of the first fixing protrusion73along the longitudinal direction of the first wall77is the operation unit side. A substantially U-shaped engagement groove96is disposed along an edge of the first wall77closer to the base95from the distal tip side toward the operation unit side.

The operation unit side of the first wall77is provided with an elevator mounting hole76. The elevator mounting hole76has a circular cross section having a diameter that fits the elevator shaft82of the elevator80described withFIGS.13to17. As illustrated inFIG.20, a flange hole761is disposed in a joining area between the base95and the first wall77on the operation unit side.

As illustrated inFIG.21, the flange hole761in the base95is a rectangular hole disposed in the pedestal70disposed along the edge on the side where the first wall77rises. The long side of the flange hole761has a length substantially equal to a diameter of the elevator mounting hole76. The short side of the flange hole761has a length that allows insertion of the flange85. A length from one edge of the base95to the center of the elevator mounting hole76is substantially equal to a length from one edge of the base95to the central portion of the flange hole761in the longitudinal direction.

As illustrated inFIG.19, an edge of the flange hole761disposed in the first wall77has both ends protruding toward the elevator mounting hole76. Note that the flange hole761may have a linear edge.

As illustrated inFIG.20, the lateral face fixing protrusion74protrudes toward the opposite side of the first wall77from an end portion of the base95on the operation unit side. A chamfer, or what is called an R-chamfer, is formed on an edge of the lateral face fixing protrusion74on the distal tip side. The edge of the lateral face fixing protrusion74on the distal tip side may be what is called a C-chamfer.

FIG.22is a front view of the cover52.FIG.23is a view of the cover52as seen from the side where the cover52is to be mounted on the endoscope10. The configuration of the cover52will be described with reference toFIGS.10to12,22, and23.

As described above, the cover52is a cylinder with a bottom and includes the window53opened over almost the entire length at one place on the periphery of the cover52. Furthermore, the cover52includes a pedestal fixing hole57. The pedestal fixing hole57is an example of a first fixing hole of this embodiment. As illustrated inFIG.12, the pedestal fixing hole57is a stepped through-hole disposed in the bottom of the cover52and has an outer diameter larger than an inner diameter.

As illustrated inFIGS.22and23, a first pedestal support451and a second pedestal support452, or stripes parallel to the axial direction of the cover52, are disposed opposite the window53. A flat pedestal positioning surface453is disposed between the first pedestal support451and the second pedestal support452. An interval between the first pedestal support451and the second pedestal support452corresponds to a width of the base95disposed in the pedestal70described with reference toFIGS.18to21.

The second fixing hole59penetrates the side closer to the opening end portion56than the second pedestal support452. The cross section of the second fixing hole59is substantially rectangular.

A second fixing protrusion58having a quadrangular prism shape protrudes inward from the bottom of the cover52. The second fixing protrusion58is disposed between the window53and the pedestal positioning surface453. An interval corresponding to a thickness of the base95is disposed between the second fixing protrusion58and the pedestal positioning surface453. The second fixing protrusion58has a size designed to be inserted into the engagement groove96disposed in the pedestal70described with reference toFIGS.18to21.

As illustrated inFIGS.11and23, the cover52includes a tabular protrusion49that protrudes inward along an edge of the window53closer to the opening end portion56. A distal tip of the protrusion49is partially provided with a first engagement portion46that protrudes inward.

The configuration of the endoscope cap50will be described with reference toFIGS.8to23. As illustrated inFIG.12, the first fixing protrusion73is inserted into the pedestal fixing hole57from the inside of the cover52. The first fixing protrusion73does not fall off the pedestal fixing hole57by the action of the lock disposed in the first fixing protrusion73.

As illustrated inFIG.9, the base95is sandwiched between the first pedestal support451and the second pedestal support452. Accordingly, the pedestal70does not rotate around the first fixing protrusion73. As illustrated inFIG.10, the second fixing protrusion58is inserted into the engagement groove96, and the end portion of the base95is sandwiched between an inner surface of the cover52and the second fixing protrusion58.

As described above with reference toFIG.11, the lateral face fixing protrusion74penetrates the second fixing hole59. An end face of the lateral face fixing protrusion74on the operation unit side abuts against an inner surface of the second fixing hole59. The pedestal70is desirably biased toward the distal tip side by the abutting portion.

The pedestal70may be fixed to the cover52by adhesion, welding, or the like. In this case, there may be a gap between the end face of the lateral face fixing protrusion74on the operation unit side and the inner surface of the second fixing hole59. It is possible to achieve the endoscope cap50with the pedestal70being firmly held.

As illustrated inFIGS.9and10, the elevator shaft82is inserted into the elevator mounting hole76. The flange85is inserted into the flange hole761. The elevator80is rotatable about the elevator shaft82supported by the elevator mounting hole76. As illustrated inFIG.11, when the elevator80is not raised, the lever connection portion81is opened toward the opening end portion56.

As described with reference toFIG.5, the endoscope cap50is pushed into the distal tip of the insertion portion30. Accordingly, the elevator connection portion61and the lever connection portion81are engaged, and the first engagement portion46and the third engagement portion29are also engaged. In this manner, the endoscope cap50is mounted to the distal tip of the insertion portion30.

As described with reference toFIG.7, when a user operates the elevation control lever21, the lever60rotates. Along with the rotation of the lever60, the elevator connection portion61rotates, and the elevator80rises as indicated by the imaginary line inFIG.11.

FIG.24is a view for describing a state where the pedestal70and the elevator80are assembled. The elevator shaft82is inserted into the elevator mounting hole76, and the elevator80is supported by the pedestal70, being rotatable about the elevator shaft82.

The flange85is inserted into the flange hole761. Even when a force is applied in a direction perpendicular to the paper surface ofFIG.24, the elevator80does not come off the pedestal70. In other words, the flange85functions as a lock to prevent the elevator80from falling off the pedestal70.

FIGS.25to27are views for describing a method for assembling the cover52and the pedestal70. InFIGS.25to27, the cover52and the pedestal70are illustrated in a front view similar toFIG.24, and the cover52is illustrated in a cross-sectional view taken along a plane similar toFIG.12. The illustration of elastic deformation during assembly is omitted.

The pedestal70and the elevator80are inserted into the cover52from the first fixing protrusion73as illustrated inFIG.25. A distal tip of the first fixing protrusion73is brought into contact with an edge of the pedestal fixing hole57. Since the lateral face fixing protrusion74protrudes, the base95is in a state where the operation unit side rises toward the center of the cover52.

The pedestal70is pushed as illustrated inFIG.26. While the slit of the first fixing protrusion73is closed by elastic deformation, the slit passes through the small-diameter portion of the pedestal fixing hole57. The base95and the cover52also elastically deform, and the lateral face fixing protrusion74enters the second fixing holes59.FIG.26does not illustrate a state where the base95and the cover52are elastically deformed. Since the edge of the lateral face fixing protrusion74on the distal tip side is chamfered as described above, the lateral face fixing protrusion74is hardly caught at an edge of the second fixing hole59.

After that, the first fixing protrusion73returns to its original shape by resilience, and the lock at the distal tip becomes functional. Simultaneously, the pedestal70is drawn toward the bottom of the cover52, and the lateral face fixing protrusion74is engaged with the second fixing hole59as illustrated inFIG.27. In this manner, the endoscope cap50is accomplished.

According to this embodiment, the end face of the lateral face fixing protrusion74on the operation unit side abuts against the inner surface of the second fixing hole59. A frictional force acting on the abutting portion prevents the cover52and the pedestal70from coming off due to an impact or the like during transportation or storage.

Since the pedestal70is biased toward the distal tip side by the abutting portion, the cover52and the pedestal70are prevented from coming off more effectively.

According to this embodiment, it is possible to provide the endoscope cap50including the cover52and the pedestal70that hardly come off when the endoscope cap50is mounted on or dismounted from the distal tip31.

The engagement between the first fixing protrusion73and the pedestal fixing hole57and the engagement between the lateral face fixing protrusion74and the second fixing hole59are both performed by pushing the pedestal70toward the bottom of the cover52. Accordingly, it is possible to provide the endoscope cap50that is easy to assemble. Due to the easiness in assembly, it is possible to provide the endoscope cap50preferable for mass production, that is, for one-time use.

Technical features (constitutional requirements) described in the embodiments can be combined with each other, and new technical features can be formed by the combination.

The embodiments herein are disclosed for purposes of illustration in all respects and not limitation. The scope of this invention is defined not by the aforementioned significance but by the claims and intended to include all modifications within the significance and scope equivalent to the claims.

REFERENCE SIGNS LIST