JP7807337B2 - Endoscope connection structure - Google Patents

Description

The present invention relates to a connection structure for an endoscope, and in particular to a connection structure for an endoscope for connecting a bending section and a rigid tip section that constitute the insertion section of the endoscope.

Endoscopes generally have a hand-operated control section and an insertion section whose base end is connected to the hand-operated control section. The insertion section has a flexible section whose base end is connected to the hand-operated control section, and the base end of a bending section is connected to the tip end of this flexible section.

The bending section and the rigid tip section are connected to the distal end of the insertion section in the longitudinal axis direction. The bending section is constructed by connecting multiple rings (also called node rings) in the longitudinal axis direction of the insertion section. The distal ring located at the most distal end of the multiple rings that make up the bending section is connected to the proximal end of the tubular member that makes up the rigid tip section (see Patent Document 1).

The endoscope connection structure disclosed in Patent Document 1 employs a structure in which the bending section and the rigid tip section are connected by fitting the protrusion of the tip ring into the recess of the tubular member.

On the other hand, Patent Document 2 discloses a connection structure in which a piece of a bending section is inserted into a connecting ring of a flexible section, and a key (protrusion) on the connecting ring is housed in a notch in the piece to connect the flexible section and bending section.

International Publication No. 2013/125311 Japanese Patent Application Laid-Open No. 2020-168441

The connection structure of Patent Document 1 requires precise alignment of the protrusions and recesses in the circumferential direction of the longitudinal axis of the insertion section in order to fit the protrusions and recesses together. Furthermore, this requires precise connection work, which can be cumbersome.

To address this issue and simplify the process of connecting the bending section and the rigid tip section, the connection can be made easier by applying, for example, the connection structure of Patent Document 2 (a structure in which a convex portion is housed in a cutout portion) to the connection structure of Patent Document 1. With the connection structure of Patent Document 2, the convex portion and the cutout portion can be connected by roughly aligning them circumferentially around the longitudinal axis of the insertion section, and then pushing them together in the longitudinal direction, making the connection process easier.

However, the connection portion of the tubular member that connects to the distal ring is configured to be thin, for example, to prevent the diameter of the distal rigid portion from increasing. Therefore, even if the connection structure of Patent Document 2 is applied to the connection structure of Patent Document 1, it is difficult to overcome the lack of strength of the thin-walled connection portion, and there is a risk that the curved portion and the distal rigid portion may easily come apart.

As such, in the field of endoscopes, there is a demand for a connection structure that can improve the connection strength between the bending section and the rigid tip section by compensating for insufficient strength at the connection part, in order to prevent the bending section and the rigid tip section from easily coming apart.

The present invention was made in consideration of these circumstances, and aims to provide a connection structure for an endoscope that can improve the connection strength between the bending section and the rigid tip section.

To achieve the above-mentioned objectives, the endoscopic connection structure of the present invention is for connecting a tip ring located on the distal end side of the bending section to a tubular member located on the proximal end side of the rigid distal section and inserted into the tip ring. The tubular member has a guide slit formed from one end of the tubular member along the axial direction of the tubular member toward the other end of the tubular member. The tip ring is positioned with a gap from the inner peripheral surface of the tip ring and has a reinforcing rib with an arc-shaped cross section perpendicular to the axial direction of the tip ring, and a rib connector connecting the inner peripheral surface of the tip ring to the reinforcing rib. When the rib connector engages with the guide slit to connect the tubular member and the tip ring, the outer periphery of the tubular member is sandwiched between the inner peripheral surface of the tip ring and the reinforcing rib, and the outer periphery of the tubular member is supported by the reinforcing rib.

According to one aspect of the present invention, it is preferable that the reinforcing ribs extend on both sides of the rib connector in the circumferential direction of the tip ring.

According to one aspect of the present invention, it is preferable that the reinforcing rib extend on only one circumferential side of the tip ring relative to the rib connector.

According to one aspect of the present invention, it is preferable that the rib connectors are provided at multiple locations around the circumferential direction of the tip ring, and the guide slits are provided at multiple locations around the circumferential direction of the tubular member.

According to one aspect of the present invention, it is preferable that the rib connectors be provided at equal intervals around the circumferential direction of the tip ring, and the guide slits be provided at equal intervals around the circumferential direction of the tubular member.

According to one aspect of the present invention, it is preferable that the rib connectors are provided at three locations equally spaced circumferentially around the tip ring, and the guide slits are provided at three locations equally spaced circumferentially around the tubular member.

According to one aspect of the present invention, it is preferable that the distal ring is made of metal and the tubular member is made of resin.

According to one aspect of the present invention, the tubular member is provided with an elastically deformable snap-fit portion having a locking protrusion protruding from the outer periphery of the tubular member, and the tip ring is provided with a locking portion that locks onto the locking protrusion. The snap-fit portion is supported at both ends by the outer periphery of the tubular member, and preferably elastically deforms radially inward of the tubular member when the tubular member is attached to or detached from the tip ring.

According to one aspect of the present invention, the rib connector and the engaging portion are preferably positioned offset from each other in the circumferential direction of the tip ring.

This invention makes it possible to improve the connection strength between the bending portion and the tip rigid portion.

1 is an overall configuration diagram showing an example of an endoscope system. FIG. 10 is an explanatory diagram showing a duct structure for inflating and deflating two balloons. 1 is a perspective view of a main part showing a state in which a distal end rigid portion and a bending portion are connected by the endoscope connecting structure of the first embodiment. FIG. FIG. 10 is a perspective view of the main part showing the state before the distal end rigid portion and the bending portion are connected. 4 is a cross-sectional view of the distal end hard portion and the curved portion shown in FIG. 3 cut along the longitudinal axis. FIG. FIG. 2 is a perspective view showing the distal ring and the tubular member separated from each other. FIG. 7 is a perspective view showing the distal end ring shown in FIG. 6 from a different angle. FIG. 7 is a perspective view showing the distal end ring shown in FIG. 6 from a different angle. 10A to 10C are explanatory views showing the operation of engaging a guide slit with a rib connector in the endoscope connecting structure of the first embodiment. FIG. 10 is an enlarged perspective view of a main part showing a state in which a rib connector is engaged with a guide slit. 10 is an explanatory diagram showing a state in which a tubular member is supported by a second rib portion. FIG. 10 is a perspective view of a main part showing a state in which a distal end rigid portion and a bending portion are connected by an endoscope connecting structure of a second embodiment. FIG. FIG. 10 is a perspective view of the main part showing a state before the distal end rigid portion and the bending portion are connected. FIG. 2 is a perspective view showing the distal ring and the tubular member separated from each other. FIG. 10 is a perspective view showing a main part of an endoscope connecting structure according to a second embodiment. 10A and 10B are explanatory views showing the operation of the locking protrusion portion being locked into the locking hole by the endoscope connecting structure of the second embodiment.

An embodiment of an endoscope connection structure according to the present invention will be described below with reference to the accompanying drawings.

First Embodiment
First, a description will be given of the first embodiment. Below, the overall configuration of an endoscope system 1 including an endoscope 10 to which an endoscope connection structure according to the first embodiment (hereinafter referred to as an "endoscope connection structure") is applied will be described, and then the endoscope connection structure according to the first embodiment will be described in detail.

Figure 1 is an overall configuration diagram showing an example of an endoscope system 1. The endoscope system 1 of this example shown in Figure 1 is a double-balloon type endoscope system, and includes an endoscope 10, which is an electronic endoscope with a balloon, an overtube 120 with a balloon, a light source device 140, a processor device 160, a balloon controller 180, a remote controller 200, and a monitor 220.

The endoscope 10 is an endoscope to which the endoscope connection structure according to the first embodiment is applied, and includes an insertion section 12 that is inserted into a lumen of a subject (e.g., the small intestine or large intestine), and a handheld operation section 14 that is connected to the proximal end of the insertion section 12 and allows the surgeon to operate it.

A universal cord 100 is connected to the handheld control unit 14, and a light source connector 102 is provided at the tip of the universal cord 100. A cable 104 is connected to the light source connector 102, and a processor connector 106 is provided at the tip of the cable 104. The light source connector 102 and the processor connector 106 are detachably connected to the light source device 140 and the processor device 160, respectively. The handheld control unit 14 also has an air/water supply button 110, a suction button 112, a pair of angle knobs 114, and a treatment tool introduction port 116, etc.

The insertion section 12 has a tip rigid section 16 that is provided at the tip of the insertion section 12 and has an imaging element and other components built in for imaging inside the subject, a freely bendable bending section 18 connected to the base end of the tip rigid section 16, and a flexible soft section 20 connected to the base end of the bending section 18. The tip rigid section 16, bending section 18, and soft section 20 are connected together along the longitudinal axis A of the insertion section 12.

Although not shown, the rigid tip portion 16 includes a known observation window, an illumination window through which illumination light supplied from the light source device 140 is emitted, and a nozzle for supplying air and water. The rigid tip portion 16 is an example of the rigid tip portion of the present invention.

A balloon 22 is detachably attached to the rigid tip portion 16. The balloon 22 is formed into a generally cylindrical shape with narrowed ends made of an elastic material such as rubber, and has small-diameter distal and proximal ends and a central bulge. After the rigid tip portion 16 is inserted through the balloon 22 and positioned at a predetermined position on the rigid tip portion 16, the balloon 22 is fixed to the rigid tip portion 16, for example, by fitting rubber rings around the distal and proximal ends.

The bending section 18 bends up and down and left and right in conjunction with the operation of the angle knob 114 on the hand-operated control section 14. This allows the tip rigid section 16 to be oriented in the desired direction within the body. The bending section 18 is an example of a bending section of the present invention. The flexible section 20 has a length of several meters to allow the tip rigid section 16 to reach the desired location within the body.

A signal cable (not shown) is inserted inside the insertion section 12, the handheld operating section 14, and the universal cord 100, and electrically connects the image sensor built into the rigid tip section 16 to the processor connector 106. The processor unit 160 performs various image processing on the image signal from the image sensor, converting it into a video signal, which is then displayed as an observation image on the monitor 220 connected via a cable.

The overtube 120 is detachably fitted over the insertion section 12 of the endoscope 10 and comprises a gripping section 122 that is held by the surgeon, a main body 124, and a balloon 126. The gripping section 122 is a cylindrical body made of a hard material such as plastic. The main body 124 is made of a flexible material such as polyurethane and is formed into a roughly cylindrical shape, and is fitted over and fixed to the distal end of the gripping section 122.

The balloon 126 is formed into a generally cylindrical shape with its ends narrowed by an elastic material such as rubber, and has small-diameter distal and proximal ends and a bulging portion in the center. The balloon 126 is placed over the outer peripheral surface of the distal end of the main body 124 and is fixed to the main body 124, for example, by winding thread around the distal and proximal ends and applying adhesive thereto.

Figure 2 is an explanatory diagram showing the duct structure for inflating and deflating the two balloons 22, 126. Note that Figure 2 shows a simplified illustration of the endoscope 10 and overtube 120.

As shown in FIG. 2, the endoscope 10 has a conduit 24 for supplying and suctioning a fluid (e.g., air) to and from the balloon 22. The conduit 24 is disposed inside the insertion section 12, the handheld control section 14, the universal cord 100, and the light source connector 102. The conduit 24 is composed of a flexible tube, and the tip of the conduit 24 is connected to a balloon opening 26 formed on the outer surface of the rigid tip section 16. The opening 26 is formed at the mounting position of the balloon 22, and the balloon 22 is inflated and deflated by supplying and suctioning a fluid through the opening 26.

The base end of the conduit 24 is connected to a base 108 provided on the light source connector 102. A tube 118 is connected to the base 108, and the tube 118 is connected to a balloon controller 180. The balloon 22 is inflated and deflated by supplying and suctioning fluid using the balloon controller 180.

Conduits 128 and 130 are formed inside the main body 124 of the overtube 120 along the longitudinal axis of the overtube 120. Conduit 128 is a hole through which the insertion section 12 of the endoscope 10 is inserted, and the inner diameter of conduit 128 is formed slightly larger than the outer diameter of the insertion section 12.

When the overtube 120 is in use, a lubricant such as water is supplied to the inner surface of the conduit 128 (the gap between the insertion section 12 and the main body section 124) to reduce friction between the insertion section 12 and the main body section 124. The lubricant is injected into the conduit 128 (see Figure 2) using a syringe or the like (not shown) from the connector 132 shown in Figure 1.

As shown in FIG. 2, the conduit 130 is a conduit for supplying and suctioning a fluid (e.g., air) to and from the balloon 126, and is provided within the wall of the conduit 128. The tip of the conduit 130 is connected to a balloon opening 134 formed on the outer surface of the main body 124. The opening 134 is formed at the mounting position of the balloon 126, and the balloon 126 is inflated and deflated by supplying and suctioning a fluid through the opening 134.

A tube 136 is connected to the proximal end of the conduit 130, and a connector 137 is connected to the proximal end of the tube 136. A tube 138 is connected to the connector 137, and the tube 138 is connected to a balloon controller 180. The balloon 126 is inflated and deflated by supplying and suctioning fluid using the balloon controller 180.

The balloon controller 180 supplies and suctions fluid separately to the balloon 22 on the endoscope 10 side and the balloon 126 on the overtube 120 side in order to alternately inflate and deflate them, and includes a pump, solenoid valves, etc. The balloon controller 180 is electrically connected to the remote controller 200 via a cable 182.

The balloon controller 180 supplies fluid to the balloons 22, 126 to inflate them, and maintains the balloons 22, 126 in an inflated state by controlling the fluid pressure (pressure value) within the balloons 22, 126 to a constant value. The balloon controller 180 also suctions fluid from the balloons 22, 126 to deflate them, and maintains the balloons 22, 126 in a deflated state by controlling the fluid pressure within the balloons 22, 126 to a constant value.

As shown in FIG. 1, a display unit 184 is provided on the front surface of the balloon controller 180. The display unit 184 displays the pressure value, inflation state, and deflation state of the balloons 22, 126 when the balloons 22, 126 are inflated and deflated. The display unit 184 also displays an error code when an abnormality such as a rupture of the balloons 22, 126 occurs. The pressure value, inflation state, and deflation state of the balloons 22, 126 may be superimposed on the observation image of the endoscope 10 and displayed on the monitor 220. The balloon controller 180 is also provided with a power switch 186, etc.

Tubes 118, 138 for supplying fluid to and suctioning from the balloons 22, 126 are attached to the front panel 188 of the balloon controller 180. A backflow prevention unit (not shown) is provided at the connection between each tube 118, 138 and the balloon controller 180. The backflow prevention unit is constructed by incorporating a gas-liquid separation filter inside a hollow, disc-shaped case 190 that is detachably attached to the front panel 188. This backflow prevention unit prevents liquids, such as bodily fluids, from flowing into the balloon controller 180 if the balloons 22, 126 are ruptured.

The remote controller 200 has a main body case 202, and balloon operation units 204, 206, balloon pause buttons 208, 210, a stop button 212, etc. are provided on the front of the main body case 202.

The balloon operation unit 204 is a push button that operates the balloon controller 180 to supply or suck fluid into the balloon 22 to inflate or deflate the balloon 22. The balloon operation unit 206 is a push button that operates the balloon controller 180 to supply or suck fluid into the balloon 126 to inflate or deflate the balloon 126. The balloon pause button 208 is a push button that operates the balloon controller 180 to control the fluid pressure of the balloon 22 to a constant value and maintain the balloon 22 in an inflated or deflated state. The balloon pause button 210 is a push button that operates the balloon controller 180 to control the fluid pressure of the balloon 126 to a constant value and maintain the balloon 126 in an inflated or deflated state. The stop button 212 is a push button that operates the balloon controller 180 to, for example, forcibly deflate the balloons 22, 126.

Next, the endoscope connecting structure according to the first embodiment will be described in detail with reference to Figures 3 to 5. Figure 3 is a perspective view of the essential parts, showing the state in which the tip hard portion 16 and the bending portion 18 are connected by the endoscope connecting structure according to the first embodiment. Figure 4 is a perspective view of the essential parts, showing the tip hard portion 16 and the bending portion 18 in a state before they are connected, with them spaced apart in the direction of the longitudinal axis A. Figure 5 is a cross-sectional view of the tip hard portion 16 and the bending portion 18 shown in Figure 3, cut along the longitudinal axis A.

As shown in Figures 3 to 5, a tip ring 30 is disposed on the tip side of the bending portion 18. The tip ring 30 is the ring located at the most distal end in the direction of the longitudinal axis A among the multiple rings that make up the bending portion 18 (rings other than the tip ring 30 are not shown). The tip ring 30 also has a connecting ring 33 on its tip side. The tip ring 30 is an example of a tip ring of the present invention and is made of a metal such as stainless steel. Although not shown in Figures 3 to 5, all rings, including the tip ring 30, are covered by a tubular outer jacket that makes up the bending portion 18.

As shown in Figures 3 to 5, a tubular member 32 is disposed on the proximal side of the distal rigid portion 16. The tubular member 32 has a connecting tube 36 on the proximal side, and the proximal side of the outer periphery 36A of the connecting tube 36 is inserted into the connecting ring 33 of the distal ring 30 when connecting the distal rigid portion 16 and the bending portion 18. The tubular member 32 is an example of a tubular member of the present invention and is made of a resin such as polyetherimide, polyetheretherketone, polysulfone, or polyphenylsulfone.

As shown in Figure 5, the distal rigid portion 16 has a distal body 38 disposed at the distal end of the tubular member 32 and a cap 40 attached to the distal end surface of the distal body 38. The distal body 38 and cap 40 each have an opening 42 formed therein for introducing a treatment tool, and the opening 42 is connected to the treatment tool introduction port 116 (see Figure 1) via a forceps channel (not shown) or the like.

In the first embodiment, as shown in Figure 4, the tubular member 32 has a guide slit 70. The guide slit 70 is a portion that engages with a rib connector 74 (see Figure 6) provided on the tip ring 30 when the tip rigid portion 16 and the curved portion 18 are connected.

Figure 6 is a perspective view showing the distal ring 30 and the tubular member 32 separated from each other, showing the distal end side of the distal ring 30 and the proximal end side of the tubular member 32. Figures 7 and 8 are perspective views of the distal ring 30 shown in Figure 6, each viewed from a different angle.

As shown in FIG. 6 , the guide slits 70 are formed from the opening edge 37 on the base end side, which is one end of the connecting pipe 36, along the axial direction (longitudinal axis A direction) of the tubular member 32 toward the tip end side, which is the other end of the connecting pipe 36. The guide slits 70 are provided at three locations at equal intervals in the circumferential direction B. The guide slits 70 are an example of a guide slit of the present invention.

As shown in Figures 6 to 8, the tip ring 30 has a reinforcing rib 72 and a rib connector 74. The reinforcing rib 72 is spaced from the inner peripheral surface 33B of the connecting ring 33 and has an arc-shaped cross section perpendicular to the axial direction (longitudinal axis A) of the tip ring 30. The rib connector 74 connects the inner peripheral surface 33B of the connecting ring 33 to the reinforcing rib 72 and is formed in a shape that can engage with the guide slit 70, such as a rectangular block. The gap between the inner peripheral surface 33B of the connecting ring 33 and the reinforcing rib 72 is approximately equal to the thickness of the outer peripheral portion 36A of the connecting pipe 36. The rib connectors 74 are provided at three locations at equal intervals in the circumferential direction B, corresponding to the three guide slits 70. The reinforcing rib 72 is an example of a reinforcing rib of the present invention, and the rib connectors 74 are an example of a rib connector of the present invention.

Next, the procedure for connecting the rigid tip portion 16 and the bending portion 18 using the endoscope connection structure of the first embodiment will be described with reference to the operation diagram shown in Figure 9.

First, as shown in Figure 9 IXA, the tip ring 30 and the tubular member 32 are positioned opposite each other in the longitudinal axis A direction, and the guide slit 70 and the rib connector 74 are aligned in the circumferential direction B. Then, as shown in Figure 9 IXB, the outer circumferential portion 36A of the connecting tube 36 is inserted toward the tip ring 30, inserting the outer circumferential portion 36A of the connecting tube 36 into the gap between the inner circumferential surface 33B of the connecting ring 33 and the reinforcing rib 72, and the rib connector 74 engages with the guide slit 70. This restricts relative rotation between the tip ring 30 and the tubular member 32 in the circumferential direction B. Then, as shown in Figure 9 IXC, the outer circumferential portion 36A of the connecting tube 36 is inserted straight into the tip ring 30 using the guide slit 70 and the rib connector 74 as guides, connecting the tip ring 30 and the tubular member 32. The distal end ring 30 and the tubular member 32 are connected and fixed by a connecting and fixing means (not shown). The connecting and fixing means may be, for example, not limited to fastening members such as screws, adhesives, or soldering, but other known connecting and fixing means may also be used. In the endoscope connection structure of the second embodiment described below, the distal end ring 30 and the tubular member 32 are connected and fixed using a snap-fit structure.

Figure 10 is an enlarged perspective view of the main parts, viewed from the inside of the tip ring 30, when the rib connector 74 has fully engaged with the guide slit 70 (in other words, when the rigid tip portion 16 and the curved portion 18 are connected). As shown in Figure 10, when the rib connector 74 has fully engaged with the guide slit 70, the outer periphery 36A of the connecting tube 36 is sandwiched in the gap between the inner circumferential surface 33B of the connecting ring 33 and the reinforcing rib 72, and the outer periphery 36A is supported by the reinforcing rib 72. This allows the reinforcing rib 72 to compensate for any lack of strength in the connection between the tip ring 30 and the tubular member 32, thereby improving the connection strength between the rigid tip portion 16 and the curved portion 18.

Next, the shapes of the three reinforcing ribs 72 (72A, 72B, 72C) provided on the tip ring 30 will be described in detail. As shown in Figure 6, of the three guide slits 70 (70A, 70B, 70C), the reinforcing rib 72A corresponding to guide slit 70A has a first rib portion 73A and a second rib portion 73B extending on either side of the rib connector 74 in the circumferential direction B. Specifically, when the reinforcing rib 72A is viewed from the direction of arrow C in Figure 6, the first rib portion 73A extends counterclockwise and the second rib portion 73B extends clockwise relative to the rib connector 74.

In contrast, the reinforcing rib 72B corresponding to the guide slit 70B has a first rib portion 73A that extends only in the counterclockwise direction relative to the rib connector 74, as shown in Figures 6 and 7. Furthermore, the reinforcing rib 72C corresponding to the guide slit 70C has a second rib portion 73B that extends only in the clockwise direction relative to the rib connector 74, as shown in Figure 8.

The reason why the three reinforcing ribs 72 (72A, 72B, 72C) have different shapes as described above will now be explained. Four bending wires (not shown) for bending the bending portion 18 up, down, and left, and right are inserted and arranged inside the distal ring 30. The base ends of these wires are connected to a pair of angle knobs 114 (see Figure 1), and the distal ends are joined to the distal ring 30. These wires are arranged at four equal intervals in the circumferential direction B, and therefore, as shown in Figures 6 to 8, four joints 80A, 80B, 80C, and 80D for joining the wire tips are formed at equal intervals in the circumferential direction B on the distal ring 30.

Here, reinforcing rib 72A (see Figures 6 and 8) is positioned between joints 80A and 80B in the circumferential direction B, but is positioned away from joints 80A and 80B (at a position that does not interfere with joints 80A and 80B), and therefore has first rib portion 73A and second rib portion 73B that extend counterclockwise and clockwise, respectively, relative to rib connector 74. In contrast, reinforcing rib 72B (see Figures 6 and 7) is positioned between joints 80B and 80C in the circumferential direction B, but if reinforcing rib 72B were to include second rib portion 73B like reinforcing rib 72A, the second rib portion 73B would interfere with joint 80C, and therefore reinforcing rib 72B only has first rib portion 73A that does not interfere with joint 80B. Furthermore, reinforcing rib 72C (see FIG. 8) is positioned between joints 80D and 80A in the circumferential direction B. However, if reinforcing rib 72A includes first rib portion 73A, the first rib portion 73A would interfere with joint 80D. Therefore, reinforcing rib 72C only includes second rib portion 73B, which does not interfere with joint 80A. FIG. 11 is a cross-sectional view of the connection between tip ring 30 and tubular member 32, showing the outer periphery 36A of connecting tube 36 supported by reinforcing rib 72C with second rib portion 73B. Thus, the three reinforcing ribs 72 (72A, 72B, 72C) have different shapes depending on their position relative to the above-mentioned joints.

As described above, the endoscope connection structure of the first embodiment employs a configuration in which the connection portion of the tubular member 32 (the outer periphery 36A of the connecting tube 36) is supported by the reinforcing ribs 72 provided on the inside of the tip ring 30. In other words, the thin-walled outer periphery 36A is reinforced by the reinforcing ribs 72, thereby improving the connection strength between the tip ring 30 and the tubular member 32.

<Modification of the first embodiment>
Next, a modification of the first embodiment will be described. Note that this modification can also be applied to the second embodiment, which will be described later.

In the first embodiment, a configuration in which the guide slits 70 and the rib connectors 74 are each provided at three equally spaced locations in the circumferential direction B was illustrated, but this is not limited to this. For example, a configuration in which the guide slits 70 and the rib connectors 74 are each provided at one location may also be adopted. However, from the perspective of improving connection workability and increasing connection strength, it is preferable to adopt the above configuration in which the guide slits 70 and the rib connectors 74 are each provided at three equally spaced locations in the circumferential direction B.

Furthermore, the arrangement positions of the guide slits 70 and rib connectors 74 are not limited to three equally spaced locations; the guide slits 70 and rib connectors 74 may each be provided at multiple locations in the circumferential direction B. In this case, it is preferable that they be provided at equal intervals in the circumferential direction B. This allows for uniform connection strength to be obtained in the circumferential direction B.

In the first embodiment, a configuration in which the tip ring 30 is made of metal and the tubular member 32 is made of resin is exemplified, but this is not limited to this. For example, a configuration in which the tip ring 30 is made of resin and the tubular member 32 is made of metal may be adopted. However, from the perspective of increasing the connection strength and smoothly attaching the tubular member 32 to the tip ring 30, it is preferable to adopt the above configuration in which the tip ring 30 is made of metal and the tubular member 32 is made of resin.

In the first embodiment, a configuration having three reinforcing ribs 72 (72A, 72B, 72C) each with a different shape was illustrated, but this is not limited to this. For example, all three reinforcing ribs 72 may be the same shape, or some of the three reinforcing ribs may have a different shape from the other reinforcing ribs. For example, if there is no interference with other parts inside the tip ring 30 (such as the joints mentioned above), it is preferable to adopt a configuration in which all three reinforcing ribs 72 include both the first rib portion 73A and the second rib portion 73B. Furthermore, depending on the positional relationship with other parts inside the tip ring 30, all three reinforcing ribs may include only one of the first rib portion 73A and the second rib portion 73B.

Second Embodiment
Next, an endoscope connecting structure according to a second embodiment will be described.

In the second embodiment, a snap-fit structure is used to secure the connection between the tip ring 30 and the tubular member 32. In the following, we will omit a description of the parts that are common to the first embodiment and focus on the differences from the first embodiment.

Figures 12 to 15 are diagrams illustrating an endoscope connection structure according to the second embodiment. In Figures 12 to 15, components that are common or similar to those in the first embodiment are designated by the same reference numerals.

Figure 12 is a perspective view of the essential parts showing the state in which the distal end hard portion 16 and the bending portion 18 are connected by the endoscope connecting structure of the second embodiment. Figure 13 is a perspective view of the essential parts showing the state before the distal end hard portion 16 and the bending portion 18 are connected, with them separated from each other in the direction of the longitudinal axis A. Figure 14 is a perspective view showing the distal end side of the distal end ring 30 and the proximal end side of the tubular member 32. Figure 15 is a perspective view showing the essential parts of the endoscope connecting structure of the second embodiment.

In the second embodiment, as shown in Figures 13 and 14, snap-fit portions 50 are provided on the tubular member 32 to enable the distal end rigid portion 16 and the curved portion 18 to be detachably connected. The snap-fit portions 50 are provided on the outer periphery 36A of the connecting tube 36, and are provided at three locations equally spaced apart in the circumferential direction B around the longitudinal axis A. These snap-fit portions 50 and the three guide slits 70 are offset from each other in the circumferential direction B. The snap-fit portions 50 are elastically deformable and have locking protrusions 52 that protrude from the outer periphery 36A of the connecting tube 36. The locking protrusions 52 are engaged with locking holes 60 provided in the distal end ring 30 when the distal end rigid portion 16 and the curved portion 18 are connected.

The snap-fit portion 50 will now be described in detail. As shown in FIG. 15 , the snap-fit portion 50 of this example has an elastically deformable body 54 extending in the axial direction (longitudinal axis A) of the tubular member 32. The elastically deformable body 54 is an elastically deformable resin member that elastically deforms upon receiving an external force from the distal end ring 30 when connecting the distal rigid portion 16 and the curved portion 18. The elastically deformable body 54 is, for example, a rectangular plate-like body with its long sides in the longitudinal axis A direction, and a locking protrusion 52 is integrally formed on the base end side of this plate-like body. With this configuration, the distal end 54A of the elastically deformable body 54 in the longitudinal axis A direction constitutes one of the two ends of the snap-fit portion 50, and the base end 54B of the elastically deformable body 54 constitutes the other of the two ends. The distal end 54A and the base end 54B are provided on the outer periphery 36A of the connecting tube 36. As a result, the snap-fit portion 50 of this example is configured such that both ends (tip 54A and base 54B) of the elastically deformable body 54 are supported at both ends by the outer circumferential portion 36A of the connecting pipe 36. The snap-fit portion 50 is an example of a snap-fit portion of the present invention, and the elastically deformable body 54 is an example of an elastically deformable body of the present invention.

As shown in FIG. 13, the snap-fit portion 50 is provided between a pair of slits 56 formed in the outer periphery 36A of the connecting pipe 36. The pair of slits 56 are formed parallel to each other along the longitudinal axis A. With this configuration, only the tip 54A and base 54B of the snap-fit portion 50 are supported by the outer periphery 36A of the connecting pipe 36. As a result, the snap-fit portion 50 is smoothly elastically deformed radially inward of the connecting pipe 36, with the tip 54A and base 54B acting as bending fulcrums.

Also, as shown in FIG. 15, the elastically deformable body 54 is formed to be thinner than the other parts of the outer circumferential portion 36A of the connecting pipe 36, excluding the snap-fit portion 50. Here, the thin-walled part of the elastically deformable body 54 refers to the other parts of the elastically deformable body 54 excluding the base end 54B side of the elastically deformable body 54 on which the locking protrusion 52 is formed. Also, the elastically deformable body 54 is formed to be thinner in thickness as it moves away from the locking protrusion 52 toward the tip 54A.

With the snap-fit portion 50 configured in this manner, the elastically deformable body 54 is thinner than the rest of the outer circumferential portion 36A of the connecting pipe 36, excluding the snap-fit portion 50, and therefore has elasticity as a whole. As a result, the snap-fit portion 50 elastically deforms more smoothly toward the radially inner side of the connecting pipe 36. Furthermore, with the snap-fit portion 50 of this example, the elastically deformable body 54 is formed to become thinner as it moves away from the locking protrusion 52 toward the tip 54A, and therefore has even greater elasticity. As a result, the snap-fit portion 50 elastically deforms more smoothly toward the radially inner side of the connecting pipe 36.

As shown in Figures 13 and 15, the locking protrusion 52 has an inclined surface 52A that slopes toward the distal ring 30. The inclined surface 52A is formed on the base end of the locking protrusion 52 and is positioned opposite the opening edge 31 of the distal ring 30 (connecting ring 33) when the connecting tube 36 is inserted into the distal ring 30. The inclined surface 52A configured in this manner abuts against the opening edge 31 of the distal ring 30 during the insertion operation, elastically deforming the snap-fit portion 50. As a result, the snap-fit portion 50 is smoothly elastically deformed radially inward of the connecting tube 36 during the insertion operation. The locking protrusion 52 is an example of a locking protrusion of the present invention. The diameter of the circumscribed circle of the three locking protrusions 52 provided at three locations is formed to be slightly larger than the inner diameter of the connecting ring 33.

As shown in FIG. 15, the locking protrusion 52 has a hook-shaped portion 53. The hook-shaped portion 53 is provided on the tip side opposite the inclined surface 52A and is hooked into the locking hole 60 described below. The hook-shaped portion 53 also has a locking surface 53A that is locked into the locking hole 60 and prevents the tubular member 32 from separating from the tip ring 30. As an example, the locking surface 53A is formed as a vertical surface that is perpendicular to the longitudinal axis A.

As shown in Figures 12 to 15, the tip ring 30 has locking holes 60 that engage with the locking protrusions 52. The locking holes 60 are provided on the outer peripheral surface 33A of the connecting ring 33, and are provided at three locations equally spaced in the circumferential direction B around the longitudinal axis A to correspond to the positions of the locking protrusions 52. With this configuration, the hook-shaped portions 53 of the locking protrusions 52 protrude from the inner peripheral surface 33B (see Figure 16) of the connecting ring 33 toward the outer peripheral surface 33A (see Figure 16) and hook into the locking holes 60, with the locking surfaces 53A engaging with the locking holes 60. These locking holes 60 and the three rib connectors 74 are offset from each other in the circumferential direction B. The locking holes 60 are an example of a locking portion of the present invention.

As shown in Figures 13 and 14, the guide slits 70 and rib connectors 74 are positioned so that when the locking projections 52 of the snap-fit portions 50 and the locking holes 60 are aligned in the circumferential direction B, they are aligned with each other in the circumferential direction B.

Next, the procedure for connecting the rigid tip portion 16 and the bending portion 18 using the endoscope connection structure of the second embodiment will be described with reference to the operation diagram shown in Figure 16.

First, as shown in Figure 16 XVIA, the tip ring 30 and the tubular member 32 are positioned opposite each other in the direction of the longitudinal axis A, and the locking protrusions 52 of the snap-fit portions 50 are aligned with the locking holes 60 in the circumferential direction B. This aligns the guide slits 70 with the rib connectors 74 in the circumferential direction B. Then, as the outer periphery 36A of the connecting tube 36 is inserted toward the connecting ring 33 of the tip ring 30, the inclined surfaces 52A of the locking protrusions 52 come into contact with the opening edge 31 of the tip ring 30. As a result, the snap-fit portions 50 are pushed by the opening edge 31 and elastically deform radially inward of the connecting tube 36.

As shown in Figure 16 XVIB, as the insertion operation continues, the inclined surface 52A of the locking protrusion 52 is further pressed against the inner peripheral surface 33B of the connecting ring 33, causing the snap-fit portion 50 to further elastically deform radially inward of the connecting tube 36. In this way, the snap-fit portion 50 undergoes gradually greater elastic deformation in conjunction with the insertion operation of the connecting tube 36, allowing the outer peripheral portion 36A of the connecting tube 36 to be smoothly inserted into the connecting ring 33 of the tip ring 30.

As shown in Figure 16 XVIC, when the locking protrusion 52 reaches the locking hole 60, the snap-fit portion 50 is released from the pressure restriction imposed by the inner peripheral surface 33B of the connecting ring 33, and elastically returns to its original state. This causes the hook-shaped portion 53 of the locking protrusion 52 to hook into the locking hole 60, and the locking surface 53A to lock into the locking hole 60.

In parallel with the above operation, the connection portion of the tubular member 32 (the outer periphery 36A of the connecting tube 36) is supported by the reinforcing rib 72 provided on the inside of the tip ring 30, as in the endoscope connection structure of the first embodiment described above. In this way, the tip ring 30 and the tubular member 32 are connected, and as a result, the rigid tip portion 16 and the bending portion 18 are connected.

On the other hand, when removing the tubular member 32 from the tip ring 30, the locking protrusion 52 locked in the locking hole 60 is pressed radially inward of the connecting tube 36, causing the snap-fit portion 50 to elastically deform radially inward of the connecting tube 36, thereby removing the locking protrusion 52 from the locking hole 60. This allows the tubular member 32 to be removed from the tip ring 30.

As described above, the endoscope connection structure of the second embodiment employs a configuration in which the tubular member 32 is provided with an elastically deformable snap-fit portion 50 supported in a doubly supported state, and the distal ring 30 is provided with an interlocking hole 60 that interlocks with the interlocking protrusion 52 of the snap-fit portion 50. Therefore, even when a force acts on the interlocking protrusion 52 or interlocking hole 60 in a direction that disengages the interlocking protrusion 52 from the interlocking hole 60 (e.g., a direction that pulls the distal ring 30 and the tubular member 32 apart in the direction of the longitudinal axis A, or a direction that bends the distal ring 30 and the tubular member 32), the snap-fit portion 50 of this example does not easily bend. As a result, even when the above-described force is applied, the interlocking state between the interlocking protrusion 52 and the interlocking hole 60 is maintained, thereby further increasing the connection strength between the bending portion 18 and the distal hard portion 16.

<Modification of the second embodiment>
Next, a modification of the second embodiment will be described.

In the second embodiment, a configuration in which the locking protrusions 52 and the locking holes 60 are each provided at three equally spaced locations in the circumferential direction B was exemplified, but this is not limited to this. For example, a configuration in which the locking protrusions 52 and the locking holes 60 are each provided at one location may also be adopted. However, from the perspective of further increasing the connection strength described above, it is preferable to adopt the above configuration in which the locking protrusions 52 and the locking holes 60 are each provided at three equally spaced locations in the circumferential direction B.

Furthermore, the arrangement positions of the locking protrusions 52 and the locking holes 60 are not limited to three equally spaced locations; the locking protrusions 52 and the locking holes 60 may be provided at multiple locations in the circumferential direction B. In this case, it is preferable that they are provided at equal intervals in the circumferential direction B. This allows for uniform connection strength in the circumferential direction B.

In the second embodiment, a configuration is illustrated in which an elastically deformable snap-fit portion 50 is supported in a doubly supported state, but this is not limited to this. For example, a cantilevered elastically deformable snap-fit portion may be used, with the tip of each end of the snap-fit portion supported by the tubular member. However, from the perspective of increasing the connection strength between the tip ring 30 and the tubular member 32, it is preferable to use an elastically deformable snap-fit portion 50 supported in a doubly supported state.

The above describes the connection structure for an endoscope according to an embodiment, but the present invention may be improved or modified in several ways without departing from the spirit and scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ENDOSCOPIC SYSTEM 10 ENDOSCOPIC 12 INSERTION SECTION 14 PROXIMAL OPERATION SECTION 16 DISTAL HARD SECTION 18 BENDING SECTION 20 FLEXIBLE SECTION 22 BALLOON 24 DUCT 26 APERTURE 30 DISTAL RING 31 OPENING EDGE 32 TUBULATED MEMBER 33 CONNECTING RING 33A OUTER SURFACE 33B INNER SURFACE 36 CONNECTING TUBE 36A OUTER SURFACE 37 OPENING EDGE 38 DISTAL SECTION BODY 40 CAP 42 APERTURE 50 SNAP-FIT SECTION 52 LOCKING PROJECTION 52A INCLINED SURFACE 53 Hook-SHAPED SECTION 53A LOCKING SURFACE 54 ELASTIC DEFORMABLE BODY 54A DISTAL 54B BASE END 56 SLITTLE 60 LOCKING HOLE 70 GUIDE SLIT 72 REINFORCEMENT RIBS 72A REINFORCEMENT RIBS 72B REINFORCEMENT RIBS 72C REINFORCEMENT RIBS 73A FIRST RIBBON 73B SECOND RIBBON 74 RIB CONNECTOR 80A JOINT 80B JOINT 80C Joint 80D Joint 100 Universal cord 102 Light source connector 104 Cable 106 Processor connector 108 Base 110 Air/water supply button 112 Suction button 114 Angle knob 116 Treatment tool introduction port 118 Tube 120 Overtube 122 Grip 124 Main body 126 Balloon 128 Pipe 130 Pipe 132 Connector 134 Opening 136 Tube 137 Connector 138 Tube 140 Light source device 160 Processor device 180 Balloon controller 182 Cable 184 Display 186 Power switch 188 Front panel 190 Case 200 Remote controller 202 Main body case 204 Balloon operation unit 206 Balloon operation unit 208 Balloon pause button 210 Balloon pause button 212 Stop button

Claims (10)

A connecting structure for an endoscope for connecting a distal ring disposed on the distal end side of a bending portion to a tubular member disposed on the proximal end side of a rigid distal end portion and inserted into the distal ring,
the tubular member has a guide slit formed from one end side of the tubular member toward the other end side of the tubular member along the axial direction of the tubular member,
The tip ring is
a reinforcing rib disposed with a gap from an inner peripheral surface of the tip ring and having an arc-shaped cross section perpendicular to the axial direction of the tip ring;
a rib connector that connects the inner peripheral surface of the tip ring and the reinforcing rib;
and
When the rib connector is engaged with the guide slit to connect the tubular member and the tip ring, the outer circumferential portion of the tubular member is sandwiched between the inner circumferential surface of the tip ring and the reinforcing rib, and the outer circumferential portion of the tubular member is supported by the reinforcing rib.
Endoscope connection structure. The reinforcing ribs extend on both sides of the tip ring in the circumferential direction relative to the rib connector.
The connection structure for an endoscope according to claim 1 . The reinforcing rib extends on only one side of the tip ring in the circumferential direction relative to the rib connector.
The connection structure for an endoscope according to claim 1 . The rib connectors are provided at a plurality of locations in the circumferential direction of the tip ring,
The guide slits are provided at a plurality of locations in the circumferential direction of the tubular member.
The connection structure for an endoscope according to claim 1 or 2. The rib connectors are provided at equal intervals in the circumferential direction of the tip ring,
The guide slits are provided at equal intervals in the circumferential direction of the tubular member.
The connection structure for an endoscope according to claim 4. The rib connectors are provided at three locations at equal intervals in the circumferential direction of the tip ring,
The guide slits are provided at three locations at equal intervals in the circumferential direction of the tubular member.
The connection structure for an endoscope according to claim 1 or 2. The tip ring is made of metal,
The tubular member is made of resin.
The connection structure for an endoscope according to any one of claims 1 to 3. The tip ring is made of metal,
The tubular member is made of resin.
The connection structure for an endoscope according to claim 4. the tubular member is provided with an elastically deformable snap-fit portion having a locking protrusion protruding from an outer periphery of the tubular member,
The tip ring is provided with a latched portion that is latched to the latching protrusion,
The snap-fit portion is supported at both ends by the outer circumferential portion of the tubular member, and elastically deforms radially inward of the tubular member when the tubular member is attached to or detached from the tip ring.
The connection structure for an endoscope according to any one of claims 1 to 3. The rib connector and the engaged portion are provided at positions offset from each other in the circumferential direction of the tip ring.
The connection structure for an endoscope according to claim 9.