JP3821205B2 - Cable structure of electronic endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cable structure for an electronic endoscope, and more particularly to a cable structure for an electronic endoscope that transmits a video signal from a solid-state image sensor (CCD) provided in the electronic endoscope.
[0002]
[Prior art]
In the electronic endoscope, a CCD is disposed behind an imaging optical system provided in a hard portion at the distal end of the insertion portion. The CCD is fixed on a substrate made of ceramic or the like, and a large number of core wires are connected to predetermined terminals on the substrate.
[0003]
The core wire is converged in a cable composed of a conductive braided shield and a non-conductive outer sheath to constitute a multi-core cable. The multi-core cable is connected to a processor, and the processor processes the video signal photoelectrically converted by the CCD transmitted from the core wire, and displays the subject on the monitor device.
[0004]
By the way, as shown in FIG. 4, the multi-core cable is configured by winding a core wire 1 with an insulating tape 9 and further covering with a conductive braided shield 2 and a non-conductive sheath 3. The braided shield 2 is connected to the ground wire 4 in the endoscope insertion portion, and the outer skin 3 is connected to a cable protection member 5 that covers the ground wire 4 and the core wire 1.
[0005]
The connection structure between the braided shield 2 and the ground wire 4 is described in, for example, Japanese Patent Application Laid-Open No. 6-285020. FIG. 4 shows an application form in the case where a cable protection member is provided on the connection portion substrate side. The outer wire 3 is extended and twisted, and the ground wire 4 is soldered to the twisted portion. A protective tube 6 is externally fitted to the core wire 1 inside the connecting portion between the braided shield 2 and the ground wire 4. When the ends of the braided shield 2 and the ground wire 4 are scattered, they come into contact with the core wire. 1 is prevented from being damaged and short-circuited. In addition, two attachment tubes 7 and 8 are sheathed at the connection portion between the braided shield 2 and the ground wire 4. Then, the vicinity of the connection portion between the braided shield 2 and the ground wire 4 is held by the protection tube 6 and the attachment tube 7, and the cable protection member 5 is sandwiched by the attachment tubes 7 and 8. The outer cover 3 and the cable protection member 5 having different thicknesses are connected by the protective tube 6 and the attachment tubes 7 and 8.
[0006]
[Problems to be solved by the invention]
However, since the conventional cable structure requires the protective tube 6 and the mounting tubes 7 and 8, there is a disadvantage that the multi-core cable becomes thicker accordingly.
[0007]
In addition to the multi-core cable, the insertion portion of the electronic endoscope is provided with a forceps channel, a wire guide for focus adjustment, an angle operation wire, an air / water supply channel, and the like. Since the space for arranging the forceps channel and the like is limited when the thickness becomes thick, there is a demand for making the multi-core cable as thin as possible.
[0008]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cable structure for an electronic endoscope capable of thinning a multi-core cable.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a cable inserted and arranged in an endoscope insertion portion includes a core wire, a conductive shield that covers the core wire, and a non-conductive covering member that covers the shield. In the cable structure of an electronic endoscope in which the shield is connected to a lead wire, and the covering member is connected to a protective member that covers the lead wire and the core wire. The connecting portion of the shield has the lead wire connected to the shield exposed by cutting out a part of the covering member, and the protective member is externally fitted to the covering member so that the lead wire and the shield The connecting portion is covered.
[0010]
According to the present invention, since the lead wire is connected to the shield exposed by cutting out the covering member, the connecting portion between the shield and the lead wire is accommodated in the notch portion of the covering member. Therefore, since the connecting portion is not bulky, the cable can be thinned.
[0011]
Further, since the connecting portion between the shield and the lead wire is disposed in the cutout portion of the covering member, the protective member can be directly connected to the covering member, and the end portion of the shield and the leading end portion of the lead wire directly touch the core wire. Can be prevented. Therefore, the protective tube and the mounting tube are not necessary, and the cable can be made thinner accordingly.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a cable structure for an electronic endoscope according to the present invention will be described in detail below with reference to the accompanying drawings.
[0013]
FIG. 1 is an overall view of an electronic endoscope to which a cable structure according to the present invention is applied. As shown in the figure, an imaging optical system 32 is arranged in the insertion portion distal end hard portion 30 of the electronic endoscope, and an optical path conversion prism 34 is arranged behind the imaging optical system 32. A CCD 36 is provided at the exit end of the prism 34, and the CCD 36 is fixed on a substrate 38 made of ceramic or the like. A large number of core wires 12, 12,... (See FIG. 2) are connected to predetermined terminals on the substrate 38, respectively.
[0014]
The core wires 12, 12... Are converged in the multi-core cable 10 and connected to the processor 40. The processor 40 processes the video signal photoelectrically converted by the CCD 36 transmitted from the core wires 12, 12... And displays the subject image on the monitor device 42.
[0015]
As shown in FIG. 2, the multi-core cable 10 is configured by covering the core wire 12 with a conductive braided shield 16 and a covering member 18 that covers the braided shield 16. The covering member 18 is made of a nonconductive material such as a fluororesin or polyvinyl chloride. An insulator 14 is interposed between the core wire 12 and the braided shield 16 so that a polyester seal tape or the like is wound around the core wire 12. The insulator 14 is arranged slightly longer (t) than the braided shield 16, and can prevent the core wire 12 from being damaged and short-circuited when the end of the braided shield 16 directly touches the core wire 12. The multi-core cable 10 configured as described above has a characteristic that the diameter is relatively small, and is disposed in the distal end hard portion or the bending portion of the endoscope insertion portion.
[0016]
On the other hand, as shown in FIG. 2, on the side of the substrate (hereinafter referred to as CCD substrate) to which the CCD of the multi-core cable 10 is fixed, the cable protection member 26 is connected to the core 12 and the ground wire (corresponding to the lead wire) 24. It is configured by covering with. A distal end portion 24A of the ground wire 24 is connected to the braided shield 16, and a proximal end portion of the ground wire is connected to a ground terminal (not shown). Further, the cable protection member 26 is constituted by a silicon tube or a heat shrinkable tube. The multi-core cable 10 configured as described above has a characteristic that the flexibility is relatively large, and is disposed in the flexible portion of the endoscope insertion portion.
[0017]
As shown in FIG. 3, the connection structure between the ground wire 24 and the braided shield 16 first forms a U-shaped cutout groove 18 </ b> A at the end of the covering member 18 to expose the braided shield 16. Then, by soldering the tip 24A of the ground wire 24 to the exposed portion of the braided shield 16, the tip of the ground wire 24 is scattered and touches the core wire 12 directly, thereby damaging the core wire 12 and short-circuiting. Can be prevented.
[0018]
Next, the cable protection member 26 is directly attached to the end of the covering member 18 and then adhered. Thus, the cutout groove 18A is completely covered by the cable protection member 26, and the connection portion between the ground wire 24 and the braided shield 16 is protected.
[0019]
According to the cable structure configured as described above, since the connecting portion between the braided shield 16 and the ground wire 24 is housed in the notch groove 18A, the connecting portion is not bulky and the multi-core cable 10 is thinned. Can do.
[0020]
Further, since the connection portion is arranged in the notch groove 18A, the cable protection member 26 can be directly fitted onto the covering member 18 for connection, thereby eliminating the need for a mounting tube. 10 can be made thinner.
[0021]
Furthermore, the insulator 14 is arranged slightly longer than the braided shield 16, and the connecting portion is arranged in the notch groove 18A, so that the end of the braided shield 16 and the tip 24A of the ground wire 24 are directly centered. Since the contact with the wire 12 can be prevented and a protective tube for preventing a short circuit becomes unnecessary, the connection portion of the multi-core cable 10 can be made thinner accordingly.
[0022]
The present invention can be applied to any multi-core cable having a structure in which the core wire is covered with a conductive braided shield and a non-conductive covering member that covers the braided shield.
[0023]
【The invention's effect】
As described above, according to the cable structure of the electronic endoscope according to the present invention, the lead wire is connected to the shield exposed by cutting out the covering member, and the shield and the lead wire are placed in the cutout portion of the covering member. Since the connecting portion is accommodated, the connecting portion is not bulky and the cable can be made thin.
[0024]
In addition, by arranging the connecting portion between the shield and the lead wire in the cutout portion of the covering member, the protective member can be directly connected to the covering member, and the end portion of the shield and the leading end portion of the lead wire can directly touch the core wire. Since it was prevented, the protective tube and the mounting tube become unnecessary, and the cable can be made thinner accordingly.
[Brief description of the drawings]
FIG. 1 is an overall view showing an electronic endoscope adopting a cable structure according to the present invention. FIG. 2 is a cross-sectional view showing a cable structure according to the present invention. Plan view [Figure 4] Cross-sectional view of a conventional cable structure [Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Multi-core cable, 12 ... Core wire, 14 ... Insulator, 16 ... Braided shield, 18 ... Covering member, 18A ... Notch part, 24 ... Ground wire, 26 ... Cable protection member

Claims (2)

The cable inserted and arranged in the endoscope insertion portion includes a core wire, a conductive shield that covers the core wire, and a non-conductive covering member that covers the shield, and the shield is a lead wire. In the cable structure of the electronic endoscope in which the covering member is connected to a protective member that covers the lead wire and the core wire,
The connecting portion between the lead wire and the shield is
The lead wire is connected to the shield exposed by cutting out a part of the covering member, and the protective member is externally fitted to the covering member to cover the connecting portion between the lead wire and the shield. A cable structure of an electronic endoscope characterized by the above. 2. The electronic endoscope according to claim 1, wherein an insulator is interposed between the core wire and the shield so as to cover the core wire, and the insulator extends from an end portion of the shield. Mirror cable structure.

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