JPH0452729Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a fixing structure for an objective optical system at the distal end of an endoscope, and in particular, a fixing structure for fixing an objective lens and an image guide fiber to the distal end body. It is related to.

[Prior Art] Conventionally, as shown in FIG. 7, for example, the fixing structure of the objective optical system at the distal end of an endoscope is such that the vicinity of the rear end of the distal end main body 51 is fixed with a curved exterior tube 52. While covering and sealing, the objective lens 53 is attached to the tip body 51 via the lens frame 53a.
The end cap of the image guide fiber 54 was fixed to the tip main body 51 with a fixing screw 55 inside the exterior tube 52. 5
1a is a metal part of the tip main body, and 51b is a synthetic resin cover part. Reference numeral 56 denotes a light guide fiber, which is fixed to the tip main body 51 with fixing screws 57 in the same manner as the image guide fiber 54.

[Problems that the invention attempts to solve] In conventional endoscopes, the tip body has a total length of 1
It was approximately 2 cm in length and was made of metal, or the outer surface of the metal part was covered with a synthetic resin cover as described above. However, for example, in the case where an electronic scanning type ultrasonic element is attached to the tip body, the length of the tip body becomes several times that of the conventional one.
Furthermore, for electrical safety reasons, it is desirable that the entire tip body be made of electrically insulating synthetic resin.

However, synthetic resins suitable for use inside body cavities for the tip body of endoscopes generally do not have good adhesive properties, so if the tip body is made entirely of synthetic resin, water may leak from the joint of the objective lens, etc. It has the disadvantage that it tends to leak, and if water leaks, the endoscope becomes unusable. Additionally, if the total length of the tip body increases several times, it becomes necessary to use an image guide fiber with a particularly long base.
The disadvantage of manufacturing such custom image guide fibers is that they are extremely expensive.

This invention eliminates such drawbacks of the conventional method,
The purpose of the present invention is to provide a structure for fixing an objective optical system at the tip of an endoscope, which can easily and reliably fix a normal-sized image guide fiber and an objective lens to a long tip body made of synthetic resin. .

[Means for Solving the Problems] In order to solve the above-mentioned problems, the fixing structure of the objective optical system at the distal end of the endoscope according to the present invention is as follows:
The tip body is made of electrically insulating synthetic resin, the outer periphery near the rear end is covered with an exterior member and sealed watertight, and the optical fiber alignment parts at both ends are hardened and molded into a rod shape. An image guide fiber whose fibers are loosened and covered with a flexible tube, an objective lens that forms an observation image on the incident side end face of the image guide fiber, and the objective lens is inserted into the tip of the image guide fiber. and a short tube for connecting and fixing these, and a short tube into which the short tube is inserted and fixed on the distal side, and the rear side extends around the flexible tube and extends approximately the entire length into a through hole drilled in the tip main body. A long pipe inserted in a cross-section,
It is characterized by comprising a sealing material applied between the long tube and the through hole, and a fixing screw that fixes the rear portion of the long tube inside the exterior member within the through hole.

[Operation] The distal end of the image guide fiber and the objective lens are fitted into a short tube and connected and fixed, and the short tube is fitted and fixed to the tip of the long tube. Then, the long tube is inserted into the through hole of the tip body over almost its entire length, and the gap is sealed by the sealing material, and the rear side of the long tube is inserted into the tip body through the fixing screw inside the exterior member. Fixed.

[Example] An example of the present invention will be described based on FIGS. 1 to 6.

FIG. 2 is an overall side view of the endoscope. Reference numeral 1 denotes a distal end body provided at the distal end of the insertion section. are connected. Reference numeral 27 denotes, for example, an electronic scanning type ultrasonic transmitting/receiving element, which is provided in the tip main body 1 facing upward.

FIG. 3 is a front view of the tip body 1, which is formed into an elliptical cross section in order to reduce the cross-sectional area and minimize patient pain.
An illumination window 5 and an air/water supply nozzle 6 are arranged on the end face with an observation window 4 in between. The outlet of the air/water supply nozzle 6 is arranged toward the observation window 4.

FIG. 4 is a plan view of the tip body 1, and 7 is a plan view of the tip body 1.
It is an elastic balloon attached so as to cover the outer circumferential surface of the tip body 1, and is removably fixed in a watertight manner by a ring 9 to a circumferential groove 8 formed on the outer periphery of both ends of the tip body 1. ing. In addition, each end of a liquid supply path 10 for feeding liquid into the balloon 7 and a drain path 11 for discharging liquid and air from inside the balloon 7 are open to the outer circumferential surface of the tip body 1 inside the balloon 7. .

Returning to FIG. 2, an operating section 12 is connected to the proximal end of the flexible tube section 2, and by rotating a bending operation knob 13 rotatably protruding from the operating section 12, bending can be performed. The portion 3 is bent in a predetermined direction.
Liquid feeding port 1 provided protrudingly at the bottom of the operating section 12
4 communicates with the liquid supply path 10, and this liquid supply port 14
Pour water or other liquid into the balloon 7 from
The balloon 7 can be filled with liquid and inflated.

Reference numeral 15 denotes a suction operation button, which is provided between a suction nipple 41 provided in the connector portion 40 and communicating with a suction device (not shown) and the drain path 11.
This is an operation to perform suction from inside the balloon 7. By this suction operation, it is possible to perform deaeration to remove air remaining in the balloon, or to discharge liquid from inside the balloon 7 after use.
Note that when the balloon 7 is not attached to the tip main body 1, mucus and the like in the body cavity can be discharged by suction operation.

Reference numeral 16 denotes an air/water supply operation button, which is provided between the air/water supply nozzle 6 and the air/water supply port 17 provided in the connector section 40 in communication with an air/water supply device (not shown). This is an operation for spouting air or water from the air/water supply nozzle 6. 18,1
Reference numeral 9 denotes a tube that communicates the air/water supply inlet 17 and the air/water supply operation button 16.

Reference numeral 20 denotes an eyepiece, and the image exit side end 29a of the image guide fiber whose image input side end is placed inside the observation window 4 is placed inside the eyepiece 20.

21 is a connector section 40 connected to the light source device
A light guide fiber is a flexible connecting pipe that connects the control section 12 and the light guide fiber whose light input side end is disposed at the tip of the connector section 40 and whose light output side end is disposed inside the illumination window 5. It is inserted into this connecting pipe 21.

Reference numeral 22 denotes an electrical signal connector connected to an ultrasonic transmission/reception control device (not shown), and is connected to the operating section 12 via a flexible signal cable 23.

FIG. 1 is a side sectional view of the tip body 1. FIG. The tip main body 1 is entirely made of electrically insulating synthetic resin, and an oval metal nut 24, for example, is installed in a recess formed near the rear end so as not to rotate within the recess. The joint ring 3a of the curved portion 3 is connected thereto with screws. In addition, in order to shorten the length L of the tip body 1 as much as possible, escape grooves 25 as shown in FIG. 5 are formed at four locations on the rear end of the tip body 1.
An end portion of the bending operation wire 3b is fixed to the node ring 3a within the relief groove 25. An outer skin (exterior member) 26 covering the outer circumferential portion from the curved portion 3 to the tip body 1 is watertightly adhered to the outer circumferential surface of the tip body 1.

The ultrasonic wave transmitting/receiving element 27 is provided so as to be exposed on the upper surface side of the tip body 1 and located inside the balloon 7. With current technology, the total length of such an ultrasonic element 27 is approximately 2 cm, so
The total length L of the tip body 1 is generally about 4 to 5 cm. 28 is a signal line drawn backward from the ultrasonic element 27 through the tip body 1;
The other end is connected to an electrical signal connector 22.

29 is a known image guide fiber;
The optical fibers are aligned at both ends of the metal base 29.
The optical fibers are loosened into pieces and covered with a flexible tube 29b in the middle between the two ends thereof. 3
0 is an objective lens disposed within the observation window 4 so as to form an observation image on the incident side end surface of the image guide fiber 29, and this objective lens 30 and the base 29a of the image guide fiber are made of a common metal. It is fitted into the short tube 31 and fixed with adhesive in a watertight manner.

A through hole 32 is bored in the longitudinal direction of the tip body 1. Then, the short tube 31 is fitted into the distal end side of the metal long tube 33 which is fitted over the entire length into the through hole 32 and is joined and fixed in a watertight manner. It surrounds the flexible tube 29b. That is, since the image guide fiber 29 and the long tube 33 are fixed to each other via the short tube 31, the inner diameter of the long tube 33 is larger than the outer diameter of the image guide fiber 29, so that the covered part by the flexible tube 29b can be extended. It can be inserted into the tube 33. And long pipe 33
A sealing material is applied between the outer periphery of the tube 33 and the through hole 32 to prevent water from entering the inside through the gap between the long tube 33 and the through hole 32. The sealing material may or may not have adhesive properties.

34 is the tip main body 1 inside the outer skin 26.
This is a fixing screw screwed into the long tube 33 and presses the rear portion of the long tube 33 into the through hole 32 to fix it.

FIG. 6 is a sectional view of the tip body 1 at a cut plane including the illumination window 5, in which the light guide fiber 35 is fixed to the tip body 1 in the same manner as the image guide fiber. In the figure, 35a is the tip of the light guide fiber, 35b is a flexible exterior tube, and the tip 35a is the long tube 36.
The long tube 36 has a sealing material applied to its outer peripheral surface over almost its entire length, and is fixed to the tip body 1 with a fixing screw 37 on the rear end side surrounding the exterior tube 35b. has been done.

[Effects of the invention] According to the fixing structure of the objective optical system at the tip of the endoscope of the present invention, the long tube to which the image guide fiber and the objective lens are fixed can be inserted over almost the entire length into the through hole of the tip body. Since it is inserted and the gap is sealed with a sealant, a complete watertight seal is achieved even if the tip body is made of synthetic resin with low adhesiveness.
Furthermore, since the fixing screw that fixes the long tube is placed inside the part that is watertightly sealed by the exterior member, there is no risk of water leakage, and the objective optical system can be securely fixed.

Furthermore, the image guide fiber and the long tube are fixed together via a short tube, and since the inner diameter of the long tube is larger than the outer diameter of the image guide fiber, the flexible tube covering portion of the image guide fiber is inserted into the long tube. be able to. Therefore, a normal-sized image guide fiber with a short hard tip can be assembled into the tip body with a long overall length, so there is no need to use a specially made image guide fiber, and cost increases can be suppressed. It has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a fixing structure for an objective optical system according to an embodiment of the present invention, Fig. 2 is an overall side view of an endoscope in which the embodiment is adopted, and Fig. 3 is a main body of the distal end thereof. 4 is a plan view of the tip main body, FIG. 5 is a partial perspective view of the rear end of the tip main body, and FIG. 6 is a cross-sectional view of the tip including the illumination window. Partial side sectional view of main body, No. 7
The figure is a side cross-sectional view of a conventional objective optical system fixing structure. 1... Tip body, 26... Outer skin (exterior member),
27... Ultrasonic transmitting/receiving element, 29... Image guide fiber, 29a... Base, 29b... Flexible tube, 30... Objective lens, 31... Short tube, 32... Through hole, 33... Long pipe, 34...fixing screw.

Claims (1)

[Scope of utility model registration request] The tip main body is made of electrically insulating synthetic resin, the outer periphery near the rear end is covered with an exterior member and sealed watertight, and the optical fiber alignment parts at both ends are hardened and molded into a rod shape, and the middle part is made of each optical fiber. An image guide fiber whose fibers are loosened and covered with a flexible tube, an objective lens that forms an observation image on the incident side end face of the image guide fiber, and the objective lens is inserted into the tip of the image guide fiber. and a short tube for connecting and fixing these, and a short tube into which the short tube is inserted and fixed on the distal side, and the rear side extends around the flexible tube and extends approximately the entire length into a through hole drilled in the tip main body. A long pipe inserted across the body, a sealing material applied between the long pipe and the through hole, and a fixing screw for fixing the rear portion of the long pipe in the through hole inside the exterior member. A fixing structure for an objective optical system at a distal end of an endoscope, characterized by comprising: