WO2012107065A1 - Endoscope with a headpiece and rotatable shaft tube - Google Patents

Abstract

An endoscope (1), with a shaft part (2) through which an optical system (21) and a light guide (13) extend and on the proximal end of which a headpiece (3) is secured in which are arranged a video camera (11) coupled to the optical system (20, 21) and an LED light source (17) coupled to the light guide (12, 13), is characterized in that the headpiece (3), at a coupling face (4) passing through the endoscope (1), is secured on the shaft part (2) so as to be able to rotate about the axis of the optical system (20, 21), in that the distal front face of the proximal light guide (12) arranged in the headpiece (3) and the proximal front face of the light guide (13) arranged in the shaft part (2) are designed as concentric rings with the same radius, and in that the LED light source (17) is coupled to the annular proximal front face of the proximal light guide (12).

Description

 ENDOSCOPE WITH A HEAD PIECE AND A ROTATABLE SHAFT TUBE

The invention relates to an endoscope referred to in the preamble of claim 1 and a head piece for it.

In endoscopes with the video camera positioned proximally, it is often placed in a separable header which may be removable for cleaning and maintenance or interchangeable to select another combination. An LED light source, which is increasingly used in endoscopes, is also well located in this header, e.g. B. also with regard to the supply connections.

DE 10 2008 055 629 AI shows a generic endoscope that shows this construction. However, this known construction has a number of disadvantages. The light guide is routed around the coupling point outside of the endoscope. This results in a technically complex construction. The camera is not rotatable relative to the shaft part, which is disadvantageous in an endoscope with a laterally looking lens. Furthermore, the arrangement of the LED light source in the header causes problems in dissipating the heat generated.

CONFIRMATION COPY The object of the present invention is to avoid the problems mentioned in a generic endoscope.

This object is achieved with the features of the characterizing part of claim 1 and claim 6.

According to the invention, the head piece is rotatably coupled to the shaft part. This eliminates the known problems with oblique-looking endoscopes, in which when changing the line of sight by rotating the shaft part, the image is rotated and the camera can be rotated accordingly to raise the image again. On the coupling surface of the endoscope continuous light guide is separated, wherein both optical fiber parts form matching aligned rings on the coupling surface, which allow independent of the rotational position, a light transmission. The coupling of the LED light source to the annular end face of the proximal light guide results in a distribution of the LED light source over a ring of larger circumference. A strong heat concentration is thereby avoided and the resulting heat can be dissipated more easily. The head piece can be easily removed, e.g. To connect with another shaft part, or to make it easier to clean.

Advantageously, the features of claim 2 are provided. This makes it possible that the light conveyed by the light guide is transmitted through the coupling surface, so the separation point between the proximal and the distal light guide on a larger cross-sectional area and thus with lower light density. The losses occurring at this point therefore have less effect, as well as disturbing mismatches. Heat losses from light losses at this point are also reduced. If the entire proximal light guide, which runs in the head piece, is of larger cross-section, be also reduces the problems in the coupling of the light at its proximal end face accordingly.

The LED light source can be z. B. in the axial direction radically coupled to the end face of the proximal light guide. Advantageously, however, the features of claim 3 are provided. A beam deflecting device, the z. B. by prisms or with a bent light guide can be realized, allows an arrangement of the LED light source radially outside the proximal light guide. This means that the LED light source is located on a larger radius and thus has more space available. According to claim 4, the LED light source forming individual LEDs can thus be arranged at a greater circumferential distance. This facilitates the construction and in turn, in turn, the heat dissipation, since z. B. larger heatsink are possible.

Advantageously, according to claim 5, an elastic seal is provided, which is arranged in the region of the coupling between the light guide and the optical system and due to their elasticity ensures a very good light-tight seal to effectively suppress the disturbing over-irradiation of the light.

An inventive head piece is specified in claim 6.

In the drawing, the invention is shown for example and schematically. Show it:

1 shows an axial section through an inventive endoscope in the region of the coupling point and

Fig. 2 is an enlarged view of the light guide of the endoscope of

Fig. 1. Fig. 1 shows an endoscope 1, consisting of a shaft part 2 and a head piece 3, which abut separable in a coupling surface 4 together.

The shaft part 2 is surrounded by a housing 5 shown in dashed lines and the head part 3 of a housing also shown in broken lines 6. In the region of the coupling surface 4 summarizes the housing 6 of the head piece 3 with a flange 7 on the housing 5 of the shaft part 2 and thus provides a Rotary guide, which allow a clean-guided rotation of the parts 2 and 3 of the endoscope 1 against each other. A locking device, not shown, can releasably secure the illustrated rotatable connection.

The rotation takes place about the axis of an optical system which consists of two parts, namely an objective 20 arranged in the head part 3 and an image conductor 21 arranged in the shaft part 2. The objective 20 has a proximal system tube 8 and the image guide 21 has a distal system tube 9 on. In the illustrated embodiment, highly schematic lenses 10 are indicated in the system tubes 8 and 9, respectively. In this case, the image conductor 21 may be formed as an eyepiece and in the main part of its length as an image guide with rod lenses in its proximal end portion lying towards the coupling surface 4. In a manner not shown, the system tubes 8 and 9 may be closed at their ends lying to the coupling surface with windows to seal the sensitive image conductors 20 and 21.

The lens 20 is the lens of a camera 1 1. At the distal, not shown in FIG. 1 distal end of the shaft part 2, sitting in front of the end of the image guide 21, z. B. in the tail of the distal system tube 9, an unillustrated further lens, the lens of the endoscope 1, which is oriented obliquely, so z. B. at an angle of 30 ° to the axis of the image guide looks. The image taken by this lens is transmitted through the optical systems 20 and 21 to the proximal end that passes through the proximal end of the optical system proximal system tube 8 is formed. There, the video camera 11 is arranged, which is connected to lines not shown outside for image transmission. Between the image conductors 20 and 21, the image must be transmitted without interference even at different angles of rotation. For this purpose, an exact coaxial alignment of the two system tubes 8, 9, is required.

Outside the system tubes 8 and 9 run concentrically formed optical fiber parts in the form of a proximal system tube 8 disposed proximal light guide 12 and a disposed outside the distal system tube 9 distal light guide 13. In the embodiment, all optical fibers are formed as glass fiber bundles, which are arranged rotationally symmetrical.

The distal optical fiber 13 is, as shown, of relatively small thickness. The proximal light guide 12 is formed substantially thicker. To compensate for this, a conical ring 14 is arranged at the proximal end of the distal light guide 13, which captures the light arriving in the proximal light guide 12 on a large surface after passing through the gap on the coupling surface 4 with a correspondingly large cross section and conical to the smaller cross section of the distal light guide 13 reduced. This cone ring is preferably formed as shown in FIG. 2 with conical fibers 15 and thus operates very low loss. It may be formed integrally with the distal light guide 13 or as an independent component.

At the gap between the proximal optical waveguide 12 and the conical ring 14, light can escape on the coupling surface 4 inwards and pass through the gap between the system tubes 8 and 9 located there into the optical system 20, 21. This would lead to strong light transmission of the transmitted image. To prevent this is in the gap between the system pipes 8 and 9, an elastic seal in the form of the illustrated, for. B. made of rubber O-ring 16 is arranged. In the illustrated arrangement, the distal end face of the proximal optical waveguide 12 and the proximal end face of the cone ring 14 lie in an annular alignment with the coupling face 4. At the distal end face of the proximal optical waveguide 12, however, isolated, spaced-apart light sources can be arranged which would be captured by the cone ring 14 in each rotational position.

In the illustrated embodiment, the proximal end face of the proximal light guide 12 is formed as a coaxially circumferential ring. There, an LED light source 17 is coupled, which is also arranged annularly and which is advantageously provided with heat sinks, not shown.

In the embodiment, the light source is connected via a prismatic ring 18 and an intermediate ring 19, both of which are e.g. Made of glass, coupled at right angles. The LED light source 17 therefore radiates radially inwards in order to radiate parallel to the axis through the light guide 12, 13 after deflection in the prism 18. The parts 17, 18 and 19 may each be annular, or as a single circumferentially spaced components. This is especially true for the LED light source 17, which advantageously consists of individual LEDs, which are spaced at a distance of z. B. 20 ° are arranged.

In a further, likewise very advantageous embodiment, instead of the LED light source 17, a further prism may first be arranged, which redirects the light direction in the axial direction. This prism could then be connected by an LED light source radiating in the axial direction. All of these possibilities can be advantageous, in particular with regard to the heat dissipation from the LEDs, that is to say the arrangement of heat sinks, in particular with respect to an equally possible arrangement of LEDs directly on the end face of the proximal light guide 12.

Claims

CLAIMS: 1. endoscope (1) with a shaft part (2), which is passed through by an optical system (21) and a light guide (13) and at the proximal end of a head piece (3) is fixed, in which a to the optical system ( 20, 21) coupled to the video camera (11) and to the light guide (12, 13) coupled LED light source (17) are arranged, characterized in that the head piece (3) on a the endoscope (1) passing through the coupling surface (4) rotatably mounted on the shaft part (2) about the axis of the optical system (20, 21) such that the distal end face of the proximal light guide (12) arranged in the head piece (3) and the proximal end face of the light guide (13) arranged in the shaft part (2) ) are formed concentrically annular with the same radius and that the LED light source (17) is coupled to the annular proximal end face of the proximal light guide (12). 2. An endoscope according to claim 1, characterized in that the distal end face of the proximal light guide (12) is greater than the cross section of the distal light guide (13) at a distance from the coupling surface (4), wherein the proximal end region (14) of the distal light guide (13) has a widening cross-section in the proximal direction. 3. An endoscope according to one of the preceding claims, characterized in that the LED light source (17) via a Strahlumlenkungsein- direction (18) to the light guide (12) is coupled. 4. An endoscope according to one of the preceding claims, characterized in that the LED light source (17) has individual circumferentially distributed LED's. 5. An endoscope according to any preceding claim, characterized in that in the region of the coupling surface (4) an elastic seal (16) between the light guide (12, 13, 14) and the optical system (20, 21) is arranged. 6. head piece (3) of an endoscope (1) according to any one of claims 1-5.