Endoscope
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- シエ チャン-ビ
- Filing Date
- 2024-12-18
- Publication Date
- 2026-07-30
AI Technical Summary
【0006】 本開示の他の特徴及び利点は、添付の図面を参照する以下の実施形態の詳細な説明において明白になる。
Smart Images
Figure 0007897918000001 
Figure 0007897918000002 
Figure 0007897918000003
Abstract
Description
Technical Field
[0001] The present disclosure relates to medical devices, and more particularly to endoscopes.
Background Art
[0002] Endoscopes are used to perform various medical examinations such as intestinal examinations, bronchial examinations, abdominal examinations, and thoracic examinations. Conventional endoscopes include fiber scopes or video scopes that are inserted into the patient's lumen to capture images of the patient's organs or other tissues (including humans and animals). Some endoscopes have a very complex structure to obtain clear images or perform some surgical procedures, resulting in a high manufacturing cost of the endoscope. For cost reduction, it is common to reuse the endoscope after sterilization.
[0003] However, when using an endoscope on patients suffering from highly infectious diseases such as acquired immunodeficiency syndrome (AIDS) and coronavirus disease 2019 (COVID-19), the sterilization procedure of the endoscope needs to be thoroughly carried out due to higher safety standards, which will be time-consuming and costly. On the other hand, when using disposable endoscopes, there will be concerns about the cost.
Summary of the Invention
Problems to be Solved by the Invention
[0004] Therefore, an object of the present disclosure is to provide an endoscope that can at least reduce one of the drawbacks associated with the above prior art.
Means for Solving the Problems
[0005] According to this disclosure, the endoscope includes an insertion tube device and a control device. The insertion tube device includes an elastic support unit, a lens unit and a tubular sleeve unit. The elastic support unit includes a distal disk, a proximal disk, an intermediate disk positioned between the distal disk and the proximal disk, a first spring that is flexible and connected between the distal disk and the intermediate disk, and a second spring that is flexible and connected between the intermediate disk and the proximal disk. The distal disk, the first spring, the intermediate disk, the second spring and the proximal disk are arranged coaxially with respect to each other when the first and second springs are not bent. The distal disk has a front surface and a rear surface. The rear surface of the distal disk faces the first spring. The lens unit includes a lens mount attached to the front surface of the distal disk and a first lens module attached to the lens mount for capturing images. The tubular sleeve unit is placed over the lens mount and the elastic support unit. The control device includes a grip connected to the proximal disk of the elastic support unit, an angle control module mounted on the grip and connected to the insertion tube device, and a signal line module attached to the grip and electrically connected to a first lens module for signal and power transmission. The angle control module controls the angle of the distal disk relative to the intermediate disk by being operable to move the distal disk relative to the intermediate disk and to bend a first spring.
[0006] Other features and advantages of this disclosure will become apparent in the following detailed description of embodiments with reference to the accompanying drawings. [Brief explanation of the drawing]
[0007] [Figure 1] This is a partial side view showing one embodiment of the endoscope relating to this disclosure. [Figure 2] This is a partial perspective view showing the insertion tube device of the embodiment. [Figure 3] This is a partial side cross-sectional view showing the insertion tube device of the embodiment. [Figure 4]This is a partial perspective view showing an insertion tube device in which the tubular sleeve unit of the embodiment is omitted. [Figure 5] This is a partial enlarged view of Figure 3. [Figure 6] This is a partially exploded perspective view showing the embodiment. [Figure 7] This is a partial side cross-sectional view showing the insertion tube device of the embodiment. [Figure 8] This is a partial enlargement of Figure 7. [Figure 9] This is a partial side view showing the angle control module of the control device of the embodiment. [Figure 10] This figure is similar to Figure 7, but in this embodiment, the insertion tube device is driven and bent by an angle control module. [Modes for carrying out the invention]
[0008] Referring to Figure 1, an embodiment of the endoscope 100 according to this disclosure includes a flexible insertion tube device 2 for insertion into the lumen of a patient, and a control device 8 connected to the end of the insertion tube device 2.
[0009] Referring to Figures 2, 3, and 4, the insertion tube device 2 includes an elastic support unit 3, a lens unit 4, a nozzle unit 5, a suction unit 6, and a tubular sleeve unit 7.
[0010] The elastic support member 3 includes a distal disk 31, a proximal disk 33, an intermediate disk 32 positioned between the distal disk 31 and the proximal disk 33, a first spring 34 that is flexible and connected between the distal disk 31 and the intermediate disk 32, and a second spring 35 that is flexible and connected between the intermediate disk 32 and the proximal disk 33. The distal disk 31, the first spring 34, the intermediate disk 32, the second spring 35, and the proximal disk 33 are positioned coaxially with each other when the first spring 34 and the second spring 35 are not bent. Referring further to Figure 5, the distal disk 31 has a front surface 311 and a rear surface 312. The rear surface 312 of the distal disk 31 faces the first spring 34.
[0011] Each of the distal disk 31, intermediate disk 32, and proximal disk 33 has an outer circumferential surface, and a circular groove 301 is formed on the outer circumferential surface, extending around the periphery of the outer circumferential surface. Referring further to Figure 6, the distal disk 31 has two conduit passage holes 302 that extend parallel to the central axis of the distal disk 31 and are located on either side of the first spring 34. The intermediate disk 32 has two conduit passage holes 302 that extend parallel to the central axis of the intermediate disk 32 and are located on either side of the first spring 34 and the second spring 35. The intermediate disk 32 further has two wire passage holes 303 that extend parallel to the central axis of the intermediate disk 32 and are located on either side of the first spring 34 and the second spring 35. The proximal disk 33 has two conduit passage holes 302 that extend parallel to the central axis of the proximal disk 33 and are located on either side of the second spring 35. The proximal disk 33 further has two wire passage holes 303 that extend parallel to the central axis of the proximal disk 33 and are located on either side of the second spring 35.
[0012] In this embodiment, the first spring 34 and the second spring 35 are coil springs that bendably support the distal disk 31 and the intermediate disk 32. The elastic modulus of the first spring 34 is greater than that of the second spring 35. small Because it has an elastic modulus, the first spring 34 can be bent more easily than the second spring 35.
[0013] Referring to Figures 2, 3, and 5, the lens unit 4 includes a lens base 41, a first lens module 42, and a second lens module 43. The lens base 41 is mounted on the front surface 311 of the distal disk 31 and has a front surface 411, a rear surface 412 on the opposite side of the front surface 411 that contacts the front surface 311 of the distal disk 31, and a side surface 413 that interconnects the front surface 411 and the rear surface 412. The first lens module 42 is mounted on the front surface 411 of the lens base 41. The second lens module 43 is embedded in the lens base 41 via the side surface 413 of the lens base 41.
[0014] Specifically, the first lens module 42 includes a front lens 421 for capturing a front image, a plurality of front illumination members 422 arranged around the front lens 421 to illuminate the area in front of the front lens 421, and a transparent cover member 423 attached to the lens base 41 and covering the front lens 421 and the front illumination members 422. The second lens module 43 includes a side lens 431 for capturing a side image, and side illumination members 432 arranged around the side lens 43 to illuminate the area around the side lens 431.
[0015] Referring to Figures 4, 6, and 7, the nozzle unit 5 includes a nozzle ring 51 fitted over the lens seat 41, and a first flexible conduit 52 fluidly connected to the nozzle ring 51 and extending through the distal disc 31, the intermediate disc 32, and the proximal disc 33. As shown in Figures 4 and 6, the nozzle ring 51 has an annular front surface in which a plurality of nozzles 510 are formed, which are angularly spaced apart from each other. The first flexible conduit 52 extends through one of the conduit passage holes 302 in the distal disc 31, one of the conduit passage holes 302 in the intermediate disc 32, and one of the conduit passage holes 302 in the proximal disc 33, and is connected to the control device 8 to introduce liquid or air supplied to the control device 8 into the nozzle ring 51.
[0016] The suction unit 6 includes a suction ring 61 that fits over the lens seat 41, and a second flexible conduit 62 that is fluidly connected to the suction ring 61 and extends through the distal disc 31, the intermediate disc 32, and the proximal disc 33. As shown in Figures 4 and 6, the suction ring 61 has annular sides in which a plurality of suction ports 610 are formed, which are angularly spaced apart from each other. The second flexible conduit 62 extends through one of the conduit passage holes 302 in the distal disc 31, another of the conduit passage holes 302 in the intermediate disc 32, and another of the conduit passage holes 302 in the proximal disc 33, and is connected to the control device 8 to introduce negative pressure from the control device 8 into the suction ring 61.
[0017] Referring to Figures 2, 4, 5, and 7, the tubular sleeve unit 7 is flexible and fits over the lens seat 41 and the elastic support unit 3. The tubular sleeve unit 7 includes a first silicone tube 71 that fits over the distal disc 31 and the lens seat 41, a second silicone tube 72 connected to the first silicone tube 71 and fitting over the distal disc 31 and the intermediate disc 32, a third silicone tube 73 connected to the second silicone tube 72 and fitting over the intermediate disc 32 and the proximal disc 33, and two silicone gasket rings 74 that fit over the joints of the first silicone tube 71 and the second silicone tube 72 and the joints of the second silicone tube 72 and the third silicone tube 73, sealing these joints.
[0018] Specifically, as shown in Figures 3, 5, and 7, the first silicone tube 71 is positioned to cover the nozzle ring 51 and the suction ring 61, fitting into half of the circular groove 301 of the distal disk 31 and occupying half of the circular groove 301. The first silicone tube 71 has a plurality of first through-holes 711 that are fluidly connected to the nozzle openings 510 of the nozzle ring 51, a plurality of second through-holes 712 that are fluidly connected to the suction openings 610 of the suction ring 61, and an opening 713 that is aligned with the second lens module 43, which can capture an image through the opening 713.
[0019] The second silicone tube 72 fits respectively into the circular groove 301 of the distal disk 31 and the circular groove 301 of the intermediate disk 32, and has opposite ends respectively occupying the other half of the circular groove 301 of the distal disk 31 and half of the circular groove 301 of the intermediate disk 32. The second silicone tube 72 further has two helical grooves 720 respectively formed on the inner surface and the outer surface of the second silicone tube 72 to facilitate bending. In other embodiments, the second silicone tube 72 may have only one helical groove 720 formed on one of the inner surface and the outer surface of the second silicone tube 72.
[0020] The third silicone tube 73 fits respectively into the circular groove 301 of the intermediate disk 32 and the circular groove 301 of the proximal disk 33, and has opposite ends respectively occupying the other half of the circular groove 301 of the intermediate disk 32 and the circular groove 301 of the proximal disk 33. The third silicone tube 73 further has a helical groove 730 formed on the inner surface of the third silicone tube 73 to facilitate bending.
[0021] Referring further to FIGS. 1, 5, and 9, the control device 8 includes a grip 81 connected to the proximal disk 33 of the elastic support unit 3, a liquid valve 82 and an air valve 83 attached to the grip 81 and fluidly connected to the first flexible conduit 52, a suction valve 84 attached to the grip 81 and fluidly connected to the second flexible conduit 62, an angle control module 85 installed on the grip 81 and connected to the insertion tube device 2, and a signal line module 86 attached to the grip 81.
[0022] The liquid valve 82 is adapted to be coupled to a liquid pump (not shown) and is configured to be operable to allow a flow of liquid generated by the liquid pump to be introduced into the first flexible conduit 52. The air valve 83 is adapted to be coupled to an air pump (not shown) and is configured to be operable to allow a flow of air generated by the air pump to be introduced into the first flexible conduit 52. The suction valve 84 is adapted to be coupled to a negative pressure source (not shown) and is configured to be operable to allow negative pressure generated by the negative pressure source to be introduced into the second flexible conduit 62.
[0023] The angle control module 85 includes a sprocket member 851 attached to the grip 81, a chain 853 disposed within the grip 81 and engaging with the sprocket member 851, and two tension wires 852. One of the tension wires 852 extends through one of the wire passage holes 303 in the intermediate disc 32 and one of the wire passage holes 303 in the proximal disc 33, and has ends connected to one end of the chain 853 and the rear surface 312 of the distal disc 31, respectively. The other tension wire 852 extends through the other wire passage hole 303 in the intermediate disc 32 and the other wire passage hole 303 in the proximal disc 33, and has ends connected to the other end of the chain 853 and the rear surface 312 of the distal disc 31, respectively. The ends of the tension wires 852 connected to the rear surface 312 of the distal disc 31 are located on either side of the first spring 34.
[0024] The sprocket member 851 controls the angle of the distal disk 31 relative to the intermediate disk 32 by rotatable so as to pull on one of the tension wires 852 while releasing one of the tension wires 852, thereby moving the distal disk 31 relative to the intermediate disk 32 and bending the first spring 34.
[0025] The signal line module 86 is electrically connected to the first lens module 42 and the second lens module 43, and is adapted to be signal-wise connected to an external display device (not shown) in order to transmit power to the first lens module 42 and the second lens module 43 and to transmit signals from the first lens module 42 and the second lens module 43 to the display device, thereby enabling the display device to display the image captured by the first lens module 42 and the second lens module 43.
[0026] Referring to Figures 5, 9, and 10, the endoscope 100 of this disclosure can be used in the same manner as a conventional endoscope. Specifically, by inserting the insertion tube device 2 into the patient's lumen, the first lens module 42 can capture a frontal image along the insertion direction of the insertion tube device 2, and the second lens module 43 can capture a lateral image along the lateral direction of the insertion tube device 2. Because a spiral groove 730 is formed in the third silicone tube 73, the third silicone tube 73 can be easily bent to conform to the shape of the lumen of the patient's esophagus, oral cavity, etc., when the insertion tube device 2 is inserted.
[0027] As shown in Figures 9 and 10, when the user of the endoscope 100 needs to change the imaging direction of the lens unit 4, the user changes the imaging direction of the lens unit 4 by rotating the sprocket member 851 in the desired direction to control the angle of the distal disc 31 relative to the intermediate disc 32 and the angle of the lens seat 41 relative to the intermediate disc 32. A helical groove 720 is formed in the second silicone tube 72 so as to bend easily, and the elastic modulus of the first spring 34 is greater than that of the second spring 35. small As a result, when the user controls the shooting direction of the lens unit 4, the user can easily operate the sprocket member 851 to bend the portion of the insertion tube device 2 between the distal disc 31 and the intermediate disc 32, thereby controlling the angle between the distal disc 31 and the lens seat 41 with respect to the intermediate disc 32.
[0028] When the user wishes to wash the tissue or transparent cover member 423 within the patient's lumen, the liquid valve 82 is opened to introduce pressurized liquid into the first flexible conduit 52, and the liquid jet is ejected from the nozzle 510 of the nozzle ring 51 through the first through-hole 711 of the first silicone tube 71 to wash away blood or mucus from the tissue or to clean the transparent cover member 423. The air valve 83 is opened to introduce pressurized air into the first flexible conduit 52, and the airflow is ejected from the nozzle 510 of the nozzle ring 51 through the first through-hole 711 of the first silicone tube 71 to supply air to the lumen. The suction valve 84 is opened to introduce negative pressure into the second flexible conduit 62 to perform drainage of body fluids and liquids, and to perform air suction through the suction port 610 of the suction ring 61 and the second through-hole 712 of the first silicone tube 71.
[0029] In this embodiment, the lens unit 4 is configured to include a first lens module 42 and a second lens module 43, but in other embodiments, the lens unit 4 may include only one of the first lens module 42 and the second lens module 43. For example, the lens unit 4 may include only the first lens module 42. Even in such a configuration, the user can still control the direction of the first lens module 42 as described above to change the shooting direction as needed.
[0030] In this embodiment, the tubular sleeve unit 7 is configured to include three silicone tubes, namely a first silicone tube 71, a second silicone tube 72, and a third silicone tube 73. However, in other embodiments, the tubular sleeve unit 7 may be integrally formed from a single elongated silicone tube.
[0031] The configuration of the endoscope 100 according to this embodiment significantly reduces the manufacturing cost of the endoscope 100. Therefore, when using the lower-cost endoscope 100 on patients suffering from highly contagious diseases, it can be used as a disposable instrument without much consideration of cost. Furthermore, when using the endoscope 100 on patients without highly contagious diseases, the user can selectively discard some components of the endoscope 100 that cannot withstand high-temperature sterilization. For example, after use, the elastic support unit 3 can be reused after sterilization, but the tubular sleeve unit 7, lens unit 4, nozzle unit 5, and suction unit 6 are removed and discarded. The partially disposable configuration of the endoscope 100 promotes a reduction in medical costs.
[0032] In summary, the configuration of the elastic support unit 3, the tubular sleeve unit 7, and the lens unit 4 allows for a significant reduction in the manufacturing cost of the endoscope 100 without sacrificing its basic functionality. Therefore, the endoscope 100 of this disclosure reduces the risk of infection by being used as a disposable instrument when used on patients with highly contagious diseases. Conversely, the endoscope 100 of this disclosure reduces medical costs by being used as a partially reusable instrument when used on patients without highly contagious diseases.
[0033] While embodiments and variations of the present disclosure have been described above, the present disclosure is not limited thereto and encompasses all modifications and equivalent configurations as various configurations that fall within the spirit and scope of the broadest interpretation. [Explanation of Symbols]
[0034] 100 Endoscopes 2. Insertion tube device 3 Elastic support unit 301 Circular groove 302 Conduit passage hole 303 Wire passage hole 31 Distal Disk 311 Front 312 Rear 32 Intermediate disk 33 Proximal disk 34. First spring 35. Second spring 4 Lens Units 41 Lens constellation 411 Front 412 Rear 413 Side view 42. First lens module 421 Front lens 422 Front lighting component 423 Transparent cover component 43. Second lens module 431 side lens 432 Side lighting component 5 Nozzle Unit 51 Nozzle Ring 510 Nozzle 52 First flexible conduit 6. Suction Unit 61 Suction Ring 610 Suction port 62 Second flexible conduit 7. Tubular sleeve unit 71 First Silicone Tube 711 First through hole 712 Second through hole 713 Aperture 72 Second silicone tube 720 spiral grooves 73 Third Silicone Tube 730 spiral groove 74 Silicone Gasket Rings 8 Control device 81 Grip 82 Liquid Valves 83 Air valve 84 Suction valve 85 Angle control module 851 Sprocket component 852 Tension wire 853 Chain 86 Signal Line Module
Claims
1. It includes an insertion tube device (2) and a control device (8), The insertion tube device (2) includes an elastic support unit (3), a lens unit (4), and a tubular sleeve unit (7), The elastic support unit (3) includes a distal disk (31), a proximal disk (33), an intermediate disk (32) positioned between the distal disk (31) and the proximal disk (33), a first spring (34) that is flexible and connected between the distal disk (31) and the intermediate disk (32), and a second spring (35) that is flexible and connected between the intermediate disk (32) and the proximal disk (33), wherein the first spring (34) is The distal disk (31), the first spring (34), the intermediate disk (32), the second spring (35), and the proximal disk (33) are arranged coaxially with respect to each other when the first spring (34) and the second spring (35) are not bent, and the distal disk (31) has a front surface (311) and a rear surface (312), the rear surface (312) of the distal disk (31) faces the first spring (34). The lens unit (4) includes a lens mount (41) attached to the front surface (311) of the distal disk (31), and a first lens module (42) attached to the lens mount (41) for capturing an image. The tubular sleeve unit (7) is placed over the lens seat (41) and the elastic support unit (3), The control device (8) includes a grip (81) directly connected to the proximal disk (33) of the elastic support unit (3), an angle control module (85) mounted on the grip (81) and connected to the insertion tube device (2), and a signal line module (86) attached to the grip (81) and electrically connected to the first lens module (42) for signal transmission and power transmission, wherein the angle control module (85) controls the angle of the distal disk (31) relative to the intermediate disk (32) by being operable to move the distal disk (31) relative to the intermediate disk (32) and to bend the first spring (34). Endoscope (100).
2. The tubular sleeve unit (7) includes a first silicone tube (71) that covers the distal disc (31) and the lens seat (41), a second silicone tube (72) connected to the first silicone tube (71) and covering the distal disc (31) and the intermediate disc (32), and a third silicone tube (73) connected to the second silicone tube (72) and covering the intermediate disc (32) and the proximal disc (33), wherein the second silicone tube (72) has a helical groove (720) formed on at least one of its inner and outer surfaces to facilitate bending, the endoscope (100) according to claim 1.
3. The endoscope (100) according to claim 2, wherein the third silicone tube (73) has a helical groove (730) formed on its inner surface to facilitate bending.
4. The endoscope (100) according to claim 2 or 3, wherein the tubular sleeve unit (7) further includes two silicone gasket rings (74) that are fitted over the joint portion of the first silicone tube (71) and the second silicone tube (72) and the joint portion of the second silicone tube (72) and the third silicone tube (73), respectively.
5. The endoscope (100) according to claim 1, wherein the first lens module (42) includes a front lens (421) for capturing a front image and a plurality of front illumination members (422) arranged around the front lens (421).
6. The endoscope (100) according to claim 5, wherein the first lens module (42) is attached to the lens base (41) and further includes a transparent cover member (423) that covers the front lens (421) and the front illumination member (422).
7. The lens seat (41) has a front surface (411), a rear surface (412) on the opposite side of the front surface that contacts the distal disk (31), and a side surface (413) that interconnects the front surface and the rear surface. The lens unit (4) further includes a second lens module (43) embedded in the lens seat (41) via the side surface (413) of the lens seat (41), The tubular sleeve unit (7) has an opening (713) that is aligned with the second lens module (43), The endoscope (100) according to claim 5, wherein the second lens module (43) includes a side lens (431) for capturing a lateral image through the aperture (713) and a plurality of side illumination members (432) arranged around the side lens (431).
8. The insertion tube device (2) further includes a nozzle unit (5) which includes a nozzle ring (51) that is placed over the lens seat (41), and a first flexible conduit (52) that is fluidly connected to the nozzle ring (51), extends through the distal disk (31), the intermediate disk (32), and the proximal disk (33), and is connected to the control device (8), The nozzle ring (51) has an annular front surface in which a plurality of injection ports (510) are formed, which are spaced at an angle to each other. The first silicone tube (71) covers the nozzle ring (51) and has a plurality of first through-holes (711) that are fluidly connected to the nozzle openings (510) of the nozzle ring (51). The endoscope (100) according to claim 2 or 3, wherein the control device (8) further includes a liquid valve (82) and an air valve (83) attached to the grip (81) and fluidly connected to the first flexible conduit (52).
9. The insertion tube device (2) further includes a suction unit (6) which includes a suction ring (61) that fits over the lens seat (41), and a second flexible conduit (62) that is fluidly connected to the suction ring (61), extends through the distal disc (31), the intermediate disc (32), and the proximal disc (33), and is connected to the grip (81), The suction ring (61) has an annular side surface in which a plurality of suction ports (610) are formed, which are spaced at an angle to each other. The first silicone tube (71) further covers the suction ring (61) and has a plurality of second through-holes (712) that are fluidly connected to the suction ports (610) of the suction ring (61), The endoscope (100) according to claim 8, further comprising a suction valve (84) attached to the grip (81) and fluidly connected to the second flexible conduit (62).
10. The distal disk (31) has two conduit passage holes (302) that extend parallel to the central axis of the distal disk (31) and are located on both sides of the first spring (34), The intermediate disk (32) has two conduit passage holes (302) that extend parallel to the central axis of the intermediate disk (32) and are located on both sides of the first spring (34) and the second spring (35), respectively. The proximal disk (33) has two conduit passage holes (302) that extend parallel to the central axis of the proximal disk (33) and are located on both sides of the second spring (35), The first flexible conduit (52) of the nozzle unit (5) extends through one of the conduit passage holes (302) of the distal disk (31), one of the conduit passage holes (302) of the intermediate disk (32), and one of the conduit passage holes (302) of the proximal disk (33). The endoscope (100) according to claim 9, wherein the second flexible conduit (62) of the suction unit (6) extends through another conduit passage hole (302) of the distal disk (31), another conduit passage hole (302) of the intermediate disk (32), and another conduit passage hole (302) of the proximal disk (33).
11. The intermediate disk (32) has two wire passage holes (303) that extend parallel to the central axis of the intermediate disk (32) and are located on both sides of the first spring (34) and the second spring (35), respectively. The proximal disk (33) has two wire passage holes (303) that extend parallel to the central axis of the proximal disk (33) and are located on both sides of the second spring (35), The angle control module (85) includes a sprocket member (851) attached to the grip (81), a chain (853) disposed within the grip (81) and engaging with the sprocket member (851), and two tension wires (852). One of the tension wires (852) extends through one of the wire passage holes (303) of the intermediate disk (32) and one of the wire passage holes (303) of the proximal disk (33), and has both ends connected to one end of the chain (853) and the rear surface (312) of the distal disk (31), respectively. The other of the tension wires (852) extends through the other wire passage hole (303) of the intermediate disk (32) and the other wire passage hole (303) of the proximal disk (33), and has ends that are connected to the other end of the chain (853) and the rear surface (312) of the distal disk (31), respectively. The endoscope (100) according to claim 2 or 3, wherein the sprocket member (851) is rotatable such as to release one of the tension wires while pulling on the other of the tension wires (852), thereby moving the distal disk (31) relative to the intermediate disk (32) and bending the first spring (34).