JP4801397B2 - Endoscope light source device - Google Patents

Description

  The present invention relates to a light source device for an endoscope.

The light source device of the endoscope applies light from the light source to the incident end surface of the light guide, and the emitted light from the output end surface of the light guide illuminates the inside of the body cavity. A halogen lamp having a large calorific value is generally used as the light source, and an infrared cut (IRC) filter for cutting heat rays is disposed between the light source and the incident end face of the light guide.
Japanese Patent No. 3435312 Japanese Patent No. 3462719

  Conventionally, this IRC filter has a filter holding member positioned between the light source lamp and the light guide, in which a filter storage recess and a female thread are formed concentrically (coaxially), and the filter is inserted in the storage recess. Is fixed (attached) by screwing into the female thread portion. However, the holding ring is a thin annular part, and it is very difficult to screw it into the female screw part. Also, since the filter expands due to the heat of the light source, escape must be ensured (a gap must be ensured between the suppression ring and the filter at room temperature), and damage will occur if the suppression ring is tightened too much. There was a risk of causing this.

  Accordingly, an object of the present invention is to provide an endoscope light source device in which a filter is interposed between a light source and a light guide, and the filter light source device can be easily attached / detached or replaced.

The present invention relates to an endoscope light source device in which a filter is interposed between a light source lamp and an incident end face of an endoscope light guide, and a filter holding member disposed between the light source lamp and the incident end face of the light guide. ; formed in the filter holding member, a holding cylinder portion, inner flange perpendicular to the position and the holding cylinder portion to the bottom portion of the holding tubular portion; above; holding recess portion of the filter formed in the inner flange A plurality of snap ring holding holes formed by being distributed in the circumferential direction on the holding cylinder part; and a plurality of elastically deformable legs along the holding cylinder part having a locking projection engaging and disengaging with each snap ring holding hole; And a filter holding flange extending along the inner flange, the snap ring holding the filter between the filter holding flange and the filter holding recess. ; Is characterized by comprising a.

  In the snap ring, it is desirable to form a spring portion on the filter holding flange that gives the filter holding flange an elastic deformation freedom in the axial direction in a free state in which the locking projection is inserted into the snap ring holding hole.

  In another aspect, the spring ring is provided with a spring portion that gives the filter holding flange a degree of freedom of elastic deformation in the axial direction in a free state in which the locking protrusion is inserted into the snap ring holding hole. You can also.

  The filter holding member is composed of a cylindrical member having an attachment / detachment portion of the light source lamp at one end and an attachment / detachment portion of the attachment / detachment flange of the light guide at the other end, and the configuration is simple if the inner flange is provided at the intermediate portion. Become. The filter holding recess formed on the inner flange protrudes from the light source lamp attaching / detaching portion side to the light guide attaching / detaching portion side, and the snap ring holding hole for holding the locking projection of the snap ring is located on the light source side from the inner flange. It is good to form in a cylindrical part.

  According to the present invention, in an endoscope light source device in which a filter is interposed between a light source and a light guide, it is possible to easily attach or detach the filter, and to obtain a device that does not cause damage to the filter. it can.

  1 to 4 show a first embodiment of an endoscope light source device 100 according to the present invention. The light source device 100 is provided in a part of the processor P shown in FIG. The processor P is a known processor having an image processing function and an illumination function (light source function) of an electronic endoscope, and a support mechanism for the light source device 100 is provided at a corner portion in the casing 11. As is well known, an image signal picked up by a body cavity image pickup device at the distal end of the body insertion portion of an electronic endoscope is guided to the processor P via a signal transmission cable and processed by a signal processing circuit in the processor P. After that, it is displayed as an image on the monitor. Conversely, the illumination light from the processor P (endoscope light source device 100) is guided to the illumination window at the distal end of the body insertion section via the light guide fiber, and the inside of the body cavity is illuminated.

  A holding bracket 13 is erected and fixed on the base 12 at the corner bottom of the casing 11. One end of a cylindrical member (filter holding member) 20 of the endoscope light source device 100 is fixed to the holding bracket 13 below, and a connecting portion 14 for a video signal transmission cable is formed above the holding bracket 13. Has been. The present embodiment is intended for the configuration around the cylindrical member 20.

  The cylindrical member 20 has a cylindrical shape with rotational symmetry as a whole, and one end portion thereof (the connection end portion with the holding bracket 13) is used as the attachment / detachment portion 21 of the light guide 15 (FIG. 4), and the other end portion is provided. An attachment / detachment portion 22 for the light source lamp 16 is provided. The light guide attaching / detaching portion 21 is provided with a disk flange (not shown) for connecting the light guide 15, and an incident end face of the light guide 15 inserted into the disk flange faces the light source lamp 16. The light source lamp 16 is a xenon lamp, for example, and generates a large amount of heat.

  As shown in FIGS. 1 and 3, an inward flange 23 that is orthogonal to the axis is formed in the tubular member 20 at an intermediate portion in the length direction. The central portion of the inner flange 23 is a circular light beam passage opening (center opening) 23a, and a filter holding recess 23b is formed around the light beam passage opening 23a. The filter holding recess 23b is formed as a stepped recess from the light source lamp 16 side toward the light guide 15 side. The diameter of the light beam passage opening 23a is smaller than the outer diameter of the infrared cut filter (IRC) 17, and the diameter of the filter holding recess 23b is such that the infrared cut filter 17 can be fitted. It corresponds to the outer diameter. Further, the thickness t of the inner flange 23 is slightly smaller than the thickness T of the infrared cut filter 17.

  When the light source lamp attaching / detaching part 22 side from the inner flange 23 of the cylindrical member 20 is called a holding cylinder part 20a, the holding cylinder part 20a has snap ring holding holes at two places in the diameter direction as shown in FIG. (Through hole) 24 is formed.

  2 uses the snap ring holding hole 24 to elastically hold the infrared cut filter 17 in the filter holding recess 23b with one touch. The snap ring 30 is made of a metal material having spring properties, and a pair of elastically deformable legs 32 extending in a direction parallel to the axial direction of the cylindrical member 20 having a locking projection 31 fitted into the snap ring holding hole 24. , And a filter holding flange 33 formed integrally with the distal ends of the pair of elastically deformable legs 32. The elastically deformable legs 32 extend along the inner peripheral surface of the holding cylinder portion 20 a, and the diameter of the center opening 33 a of the filter holding flange 33 is smaller than the outer diameter of the infrared cut filter 17. Therefore, the infrared cut filter 17 fitted in the filter holding recess 23b of the inner flange 23 is sandwiched between the filter holding recess 23b and the filter holding flange 33 and does not fall off.

  An annular wave spring portion 34 is formed on the filter holding flange 33 of the snap ring 30 so as to be positioned on the outer peripheral portion thereof. The annular wave spring portion 34 gives the tip end portion of the filter holding flange 33 with elasticity that enables elastic deformation in the axial direction.

  In the endoscope light source device having the above-described configuration, when the infrared cut filter 17 is held, the infrared cut filter 17 is fitted into the filter holding recess 23b with the snap ring 30 removed. In this state, the snap ring 30 is deformed so as to reduce the distance between the pair of elastically deformable legs 32, and the filter holding flange 33 is fitted into the holding cylinder portion 20 a so as to approach the inner flange 23, and the locking protrusion 31. And the position of the snap ring holding hole 24 are matched. When the external force applied to the elastically deformable legs 32 is released, the locking projection 31 is fitted into the snap ring holding hole 24 to prevent the snap ring 30 from coming off. At this time, the inner peripheral portion of the filter holding flange 33 The infrared cut filter 17 is sandwiched between the holding recess 23b. That is, due to the elasticity of the annular wave spring portion 34, the filter holding flange 33 presses the infrared cut filter 17 against the filter holding recess 23b. Therefore, in this mounted state, the infrared cut filter 17 does not play (move) in the filter holding recess 23b, and no abnormal noise is generated. On the other hand, when the light source lamp 16 is turned on, the infrared cut filter 17 expands. During the expansion, the annular wave spring portion 34 of the snap ring 30 allows the filter holding flange 33 to be elastically deformed, so that the infrared cut filter 17 is not damaged. Of course, depending on the material and thickness of the snap ring 30, it is possible to allow a certain elastic deformation of the filter holding flange 33 without forming the annular wave spring portion 34.

  5 to 7 show another embodiment of the endoscope light source device according to the present invention. This embodiment shows another shape of the snap ring 30A, and the configuration on the cylindrical member 20 (holding cylinder portion 20a) side is the same as that of the first embodiment. The snap ring 30A of this embodiment forms a locking projection 31A that engages with and disengages from the snap ring holding hole 24 over the entire width of the pair of elastically deformable legs 32. Further, following this locking projection 31A, On the filter holding flange 33 side, a wave spring portion 34 </ b> A is formed which gives elasticity that enables elastic deformation of the filter holding flange 33 in the axial direction.

  In this embodiment, when the infrared cut filter 17 is set, the infrared cut filter 17 can be held in the filter holding recess 23b of the inner flange 23 by the engagement of the locking projection 31A and the snap ring holding hole 24. When the infrared cut filter 17 is thermally expanded, the wave spring portion 34A is elastically deformed to give a degree of freedom to the position of the filter holding flange 33, so that the infrared cut filter 17 can be prevented from being damaged.

In the said embodiment, although the infrared cut filter was shown as a filter, this invention is applicable also to filters other than an infrared cut filter. Moreover, in the said embodiment, although the snap ring holding hole 24 and the latching protrusion 31 (31A) are two places of radial direction, if they are disperse | distributed to the circumferential direction, three or more may be sufficient. More equiangular intervals are preferred.

It is a perspective view of the decomposition | disassembly state of the principal part which shows one Embodiment of the light source device for endoscopes of this invention. It is a perspective view which shows the single-piece | unit shape of the holding ring of the endoscope light source device of FIG. It is a longitudinal cross-sectional view of the state which hold | maintained the filter with the holding ring. It is a perspective view of the whole endoscope light source device of the present invention. It is a longitudinal cross-sectional view of the decomposition | disassembly state of a filter holding member, a filter, and a holding ring which shows another embodiment of the light source device for endoscopes of this invention. It is a longitudinal cross-sectional view of the assembly state. It is a perspective view which shows the single-piece | unit shape of the holding ring of the light source device for endoscopes of FIG. 5, FIG.

Explanation of symbols

P processor 100 Endoscope light source device 11 Casing 12 Base 13 Holding bracket 14 Cable connection portion 15 Light guide 16 Light source lamp 17 Infrared cut filter 20 Tubular member (filter holding member)
20a Holding cylinder part 21 Light guide attaching / detaching part 22 Light source lamp attaching / detaching part 23 Inner flange 23a Light beam passage opening 23b Filter holding recess 24 Snap ring holding hole 30 30A Snap ring 31 31A Locking protrusion 32 Elastic deformation leg 33 Filter holding flange 34 Annular Wave spring part 34A Wave spring part

Claims (5)

In an endoscope light source device in which a filter is interposed between a light source lamp and an incident end face of an endoscope light guide,
A filter holding member disposed between the light source lamp and the incident end face of the light guide;
A holding cylinder part formed on the filter holding member, and an inner flange positioned at the bottom of the holding cylinder part and orthogonal to the holding cylinder part ;
A holding recess of the filter formed on the inner flange;
A plurality of snap ring holding holes formed dispersed in the holding cylinder part in the circumferential direction; and a plurality of elastically deformable legs along the holding cylinder part, each having a locking projection engaging with and disengaging from each snap ring holding hole; A snap ring having a filter holding flange extending along the inner flange and connected to the plurality of elastically deformable legs, and holding the filter between the filter holding flange and the filter holding recess;
An endoscope light source device comprising: 2. The endoscope light source device according to claim 1, wherein the snap ring has an elastic deformation in an axial direction of the filter holding flange in a free state in which the locking protrusion is inserted into the snap ring holding hole. An endoscope light source device in which a spring portion for giving a degree of freedom is formed. 2. The endoscope light source device according to claim 1, wherein the snap ring is elastically deformed in the axial direction of the filter holding flange in a free state in which the locking protrusion is inserted into the snap ring holding hole on the elastically deformable leg. An endoscope light source device in which a spring portion for giving a degree of freedom is formed. The endoscope light source device according to any one of claims 1 to 3, wherein the filter holding member has a tubular shape having an attachment / detachment portion of the light source lamp at one end portion and an attachment / detachment portion of an attachment / detachment flange of the light guide at the other end portion. An endoscopic light source device comprising a member and provided with the inner flange at an intermediate portion thereof. 5. The endoscope light source device according to claim 4, wherein a filter holding recess formed in the inner flange protrudes from the light source lamp attaching / detaching portion side to the light guide attaching / detaching portion side, and holds the locking protrusion of the snap ring. The endoscope light source device, wherein the snap ring holding hole is formed in the cylindrical portion on the light source side from the inner flange.