Endoscope and endoscope system

Abstract

To achieve both durability and ease of work such as connection work of an endoscope cable in an endoscope having an endoscope cable for electrically connecting the tip of the endoscope inserted into a body cavity and a connector at the rear end of the endoscope connected to a processor for an endoscope.SOLUTION: An endoscope cable includes: an overall shield part having a plurality of individual cables, composed of a metal element wire group with an electric shield function for surrounding the whole of the plurality of individual cables; and a cable core wire composed of a metal element wire group in each of the individual cables. The metal element wire group in at least one of the overall shield part and the cable core wire is composed by combining a plurality of kinds of metal element wires whose compositions are mutually different.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an endoscope inserted into a body cavity and an endoscope system.

Background Art

[0002] An endoscope is a device that is inserted into a body cavity such as the human body to observe the living tissue on the inner surface of the body cavity. The endoscope includes an endoscope cable that electrically connects between the tip of the endoscope inserted into the body cavity and a connector at the rear end of the endoscope connected to an endoscope processor. The endoscope cable transmits an instruction signal for instructing an imaging operation from the endoscope processor to an imaging element provided at the tip of the endoscope, and transmits an image signal obtained by imaging to the endoscope processor. Further, in addition to the imaging element provided at the tip, when an LED light source element is provided at the tip, the endoscope cable transmits a power line for supplying power to the LED light source element and a control signal for controlling the on and off of the light emission of the LED light source element.

[0003] Since the tip of the endoscope is inserted into the body cavity of the subject, it is desirable to make it as thin as possible in order to reduce the pain of the subject. For this purpose, it is preferable that the outer diameter of the built-in endoscope cable is small. On the other hand, since the passage in the body cavity is bent or curved, the endoscope cable is required to bend flexibly. Further, it is also required to ensure durability so that the endoscope cable does not get damaged or broken even when it is repeatedly bent and stretched so that transmission lines such as signal lines and power lines do not break. Further, in the endoscope cable, in order to block noise from the outside from the internal conductors or to prevent noise from the internal conductors from leaking to the outside, a shield portion in which a shield wire is arranged is provided so as to surround the conductors such as transmission lines for transmitting an instruction signal, a control signal, or an image signal.

[0004] In order to ensure the durability of such an endoscope cable, a highly rigid stranded wire (copper alloy) is used for each part of the conductor used in the endoscope cable. Also, a structure is known in which the diameter of the stranded wire of the external conductor constituting the shield part is different from the diameter of the stranded wire of the internal conductor, which is the signal wire, that is, the core wire (Patent Document 1). With this structure, the tensile strength, the repeated bending strength, and the repeated twisting strength can be improved.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the endoscope cable having the above structure, durability such as tensile strength, repeated bending strength, and repeated twisting strength can be ensured. However, when removing the covering (insulator) that covers the core wire of the endoscope cable and performing a connection operation to connect the core wire to each element or the port of the connector, there is a problem that the flexibility of the endoscope cable is not sufficient, so the above connection operation cannot be performed efficiently enough. If the composition of the stranded wire constituting the core wire or the shield part is changed to ensure the flexibility of the endoscope cable, the durability may not be ensured sufficiently. Thus, sufficient compatibility between the durability of the endoscope cable and the ease of operations such as connection work could not be achieved.

[0007] Therefore, an object of the present invention is to enable compatibility between the durability of an endoscope cable and the ease of operations such as connection work in an endoscope having an endoscope cable that electrically connects between the tip of the endoscope inserted into the body cavity and a connector at the rear end of the endoscope connected to an endoscope processor.

Means for Solving the Problems

[0008] One aspect of the present invention is an endoscope having an endoscope cable that electrically connects between a distal end portion of an endoscope inserted into a body cavity and a connector at a rear end portion of the endoscope that connects to an endoscope processor. The endoscope cable includes a plurality of individual cables, and includes an overall shield portion composed of a group of metal strands having an electrical shielding function surrounding the plurality of individual cables as a whole, and a cable core wire composed of a group of metal strands in each of the individual cables. The group of metal strands in at least one of the overall shield portion and the cable core wire is composed of a combination of a plurality of types of metal strands having different compositions.

[0009] It is preferable that at least one of the plurality of individual cables includes an individual cable shield portion composed of a group of metal strands having an electrical shielding function surrounding the cable core wire.

[0010] It is preferable that the group of metal strands in the individual cable shield portion is composed of a combination of a plurality of types of metal strands having different compositions.

[0011] The group of metal strands in at least two of the overall shield portion, the cable core wire, and the individual cable shield portion is composed of a combination of a plurality of types of metal strands having different compositions, and the types of metal strands used in the group of metal strands in the at least two are the same, but the ratio of the number of uses of the plurality of types of metal strands used within the group of metal strands is different between the group of metal strands in the at least two, which is preferable.

[0012] It is preferable that the group of metal strands in at least one of the overall shield portion and the individual cable is arranged along the circumference of the endoscope cable or along the circumference of the individual cable so that the plurality of types of metal strands repeat in a predetermined order.

[0013] Another aspect of the present invention is also an endoscope having an endoscope cable that electrically connects between a distal end portion of an endoscope inserted into a body cavity and a connector at a rear end portion of the endoscope that is connected to an endoscope processor. The endoscope cable includes a plurality of individual cables, and includes an overall shield portion composed of a group of metal wires having an electrical shielding function surrounding the plurality of individual cables as a whole, and a cable core wire composed of a group of metal wires in each of the individual cables. At least one of the plurality of individual cables includes an individual cable shield portion composed of a group of metal wires having an electrical shielding function surrounding the periphery of the cable core wire. Among at least two of the overall shield portion, the cable core wire, and the individual cable shield portion, the combination of the types of metal wires used for the group of metal wires is different.

[0014] It is preferable that the metal compositions are different among the plurality of types of metal wires.

[0015] The plurality of types of metal wires preferably include at least a wire made of soft copper (conforming to JIS C3102-1984 or JIS C3152-1984) and a wire made of a copper alloy having a Young's modulus larger than that of the wire made of soft copper.

[0016] The wire made of a copper alloy preferably includes a plurality of types of wires made of copper alloys having different metal compositions.

[0017] It is preferable that at least one characteristic of conductivity (JIS C3002) and Young's modulus is different among the plurality of types of metal wires having different compositions.

[0018] Still another aspect of the present invention is an endoscope system including the endoscope and an endoscope processor connected to the endoscope via the connector, outputting an instruction signal to the endoscope, and receiving an input of a signal output from the endoscope to perform signal processing. The endoscope is selected from a group of endoscopes connectable to the endoscope processor according to the site in the body cavity into which the endoscope is inserted and the usage conditions including the operation details of the endoscope. In at least two of the group of endoscopes, at least one of the combination of the types of the metal strands used for the endoscope cable and the ratio of the number of uses of a plurality of types of metal strands used within the group of metal strands is different according to the usage conditions.

Advantages of the Invention

[0019] According to the above-described endoscope, it is possible to achieve both the durability of the endoscope cable and the ease of work such as connection work.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0021] Hereinafter, the endoscope and the endoscope system according to the embodiment will be described with reference to the drawings. FIG. 1 is an external perspective view of an endoscope according to an embodiment. FIG. 2 is a block diagram showing the configuration of an endoscope system according to an embodiment.

[0022] The endoscope cable 140 (see FIGS. 3 to 6) described below achieves both durability and ease of operation such as connection work. Among the overall shield portion 160 (see FIGS. 3 to 6) and the cable core wires 142 to 152 (see FIGS. 3 to 6) provided in the endoscope cable 140, the metal wire group formed in at least one of them is composed of a combination of a plurality of types of metal wires having different compositions. Thereby, it is possible to achieve both the durability required for the endoscope cable 140 and the ease of operation such as connection work. Here, the durability can be evaluated by applying stress to the endoscope cable 140 by the following test and counting the number of broken metal wires. · A simple twisting test of repeatedly rotating the axis at a predetermined angle around the axis of the endoscope cable 140 a predetermined number of times, · A simple bending test (JIS C 3005 4.27), · A bending and twisting test of simultaneously performing the above simple twisting test and the above simple bending test, · A kink resistance test (loop tension test) of making a loop in the endoscope cable 140 and pulling it, · A mating test (JIS C 3005 4.30).

[0023] The endoscope system 1 shown in FIG. 2 is a system specialized for medical use, and mainly includes an endoscope 100, a processor 200 for an electronic endoscope, and a monitor 300. The endoscope 100 and the monitor 300 are each connected to the processor 200.

[0024] As shown in FIG. 1, the endoscope 100 includes a connector 110 and an operation unit 120, and further includes a flexible cable 130 that extends forward from the operation unit 120 and has flexibility, a distal end portion 132 and a bending tube 134 provided in front of the flexible cable 130, and a universal tube 128 that extends rearward from the operation unit 120. The connector 110 is fixed to the rear end of the universal tube 128 and is configured to be connected to the processor 200. An endoscope cable for electrically connecting between the distal end portion 132 and the connector 110 is provided in the universal tube 128 and the flexible cable 130. In the operation unit 120, the flexible cable 130, and the bending tube 134, a plurality of bending operation wires are inserted, and the tip of each bending operation wire is connected to the end of the bending tube 134. The rear end of each bending operation wire is connected to the bending operation knob 122 of the operation unit 120. The bending tube 134 bends at an arbitrary angle in an arbitrary direction according to the operation of the bending operation knob 122.

[0025] Furthermore, the operation unit 120 includes a plurality of operation buttons 124. Functions for causing each operation are assigned to the operation buttons 124 so that the distal end portion 132 performs each operation by pressing the operation buttons 124. Examples of the above operations include an operation of discharging liquid or gas from an air supply / discharge port (not shown) of the distal end portion 132 to a biological tissue that is a photographic subject, an operation of discharging the cleaning liquid supplied to the distal end portion 132 via the flexible cable 130 from a cleaning liquid discharge nozzle (not shown) of the distal end portion 132 toward the objective lens 106 provided at the distal end portion 132 to clean the surface of the objective lens 106, or an operation of sucking liquid or gas in the biological tissue from a suction port (not shown) provided at the distal end portion 132 and discharging the sucked matter to the outside. In this way, by pressing the operation button 124, the operations performed at the distal end portion 132 can be operated.

[0026] Furthermore, a forceps insertion port 126 is provided on the side of the distal end portion 132 of the operation unit 120. The forceps insertion port 126 is connected to the forceps opening of the distal end portion 132 via a tube in the flexible cable 130. Therefore, the forceps inserted from the forceps insertion port 126 and guided to the forceps opening of the distal end portion 132 can be taken out from the forceps opening to treat the biological tissue.

[0027] The distal end portion 132 is provided at the tip of the bending tube 134. The distal end portion 132 is made of a hard resin material that does not substantially elastically deform. On the distal end surface of the distal end portion 132, a light distribution lens 104 is provided as an emission window for illumination light for illuminating the biological tissue, and an objective lens 108 is further provided as an observation window.

[0028] Inside the distal end portion 132, an LED light source 102 and an imaging element 108 positioned immediately behind the objective lens 106 are provided. That is, the distal end portion 132 provided at the tip of the long flexible cable 130 includes the LED light source 102, the light distribution lens 104, the objective lens 106, and the imaging element 108. The objective lens 106 is provided in front of the imaging element 108 and forms an image of the biological tissue on the light receiving surface of the imaging element 108 within a field of view range of a predetermined field angle. In the example shown in FIG. 2, the LED light source 102 is provided in the distal end portion 132, but the LED light source 102 may be provided in the processor 200. In this case, an optical guide cable in which a plurality of optical fiber cables for transmitting illumination light extending from the processor 200 to the distal end portion 132 via the connector 110 are bundled is used. Further, instead of the LED light source 102, a light source device that emits illumination light of each color according to the characteristics of the optical filter using a white light source lamp and an optical filter may be used.

[0029] The flexible cable 130, the curved tube 134, and the distal end portion 132 form an insertion portion 135 to be inserted into the body cavity. The image signal line extending from the imaging element 108 provided in the distal end portion 132 extends from the distal end portion 132 through the curved tube 134, the flexible cable 130, and further through the inside of the operation unit 120 and the universal tube 128 to the inside of the connector 110. The connector 110 is connected to the processor 200. The processor 200 processes the image signal sent from the imaging element and controls to display the image of the subject imaged by the imaging element 108 on the monitor 300.

[0030] As shown in FIG. 2, the processor 200 of the endoscope system 1 includes a system controller 202 and a timing controller 206. The system controller 202 executes various programs stored in the memory 204 and comprehensively controls the entire electronic endoscope system 1. Further, the system controller 202 changes various settings of the electronic endoscope system 1 according to an instruction input by a user (surgeon or assistant) to the operation panel 208. The timing controller 206 outputs a clock pulse for adjusting the operation timing of each unit to each circuit in the electronic endoscope system 1.

[0031] In such a configuration, in the endoscope system 1, a display image is created in the following process. The light emitted from the LED light source 102 is irradiated as illumination light onto the biological tissue, which is the subject, through the light distribution lens 104. The reflected light from the biological tissue forms an optical image on the light receiving surface of the imaging device 108 through the objective lens 106.

[0032] The imaging device 108 is, for example, a single-plate color CCD (Charge-Coupled Device) image sensor in which various filters such as an IR (Infrared) cut filter 108a and a Bayer array color filter 108b are arranged on the light receiving surface, and generates R (Red), G (Green), and B (Blue) primary color signals corresponding to the optical image formed on the light receiving surface. Instead of the single-plate color CCD image sensor, a single-plate color CMOS (Complementary Metal Oxide Semiconductor) image sensor can also be used. In this way, the endoscope 100 uses the imaging device 108 to image the biological tissue inside the organ and generate a video signal.

[0033] Inside the connector 110 of the endoscope 100, a driver signal processing circuit 112 is provided. The driver signal processing circuit 112 performs predetermined signal processing such as color interpolation and matrix calculation on the video signal input from the imaging device 108 to generate an image signal (luminance signal Y, color difference signals Cb, Cr), and outputs the generated image signal to the image processing unit 220 of the electronic endoscope processor 200. Also, the driver signal processing circuit 112 accesses the memory 114 to read out the unique information of the endoscope 100. The unique information of the endoscope 100 recorded in the memory 114 includes, for example, the number of pixels and sensitivity of the imaging device 108, the operable frame rate, the model number, and the like. The driver signal processing circuit 112 outputs the unique information read from the memory 114 to the system controller 202.

[0034] The system controller 202 performs various calculations based on the information stored in the memory 204 and the unique information of the endoscope 100, and generates a control signal. The system controller 202 uses the generated control signal to control the operation and timing of each circuit in the electronic endoscope processor 200 so that processing suitable for the endoscope 100 connected to the electronic endoscope processor 200 is performed.

[0035] The timing controller 206 supplies clock pulses to the driver signal processing circuit 112, the image processing unit 220, and the light source unit 230 in accordance with the timing control by the system controller 202. The driver signal processing circuit 112 drives and controls the imaging device 108 at a timing synchronized with the frame rate of the video processed on the electronic endoscope processor 200 side in accordance with the clock pulses supplied from the timing controller 206.

[0036] The image processing unit 220 performs the set image processing on the image of the imaged biological tissue and outputs it as a video to the monitor 300. Also, the image processing unit 220 may perform processing on the image so that it is easier to diagnose the lesion. For example, processing that emphasizes features that can distinguish the lesion from the healthy part is performed, and information quantifying the degree of progression of the lesion is output to the monitor 300. In addition, the image processing unit 220 outputs an image obtained by extracting a part of the moving image as a still image and information obtained by quantifying the degree of progression of the lesion to the printer 400.

[0037] Specifically, the image processing unit 220 generates a video signal for monitor display of an image or the like based on the image signal input from the driver signal processing circuit 112 under the control of the system controller 202, and outputs it to the monitor 300. Further, the image processing unit 220 performs a quantification process of quantifying the feature amount of each pixel of an image that can distinguish the lesion part from the healthy part with respect to the image of the biological tissue obtained by the endoscope 100, evaluates the degree of progression of the lesion part of the image, and further generates a color map image in which the numerical value of each pixel obtained by the quantification process is replaced with a color. The image processing unit 220 generates a video signal for monitor display of the information of the result of the quantification process and the color map image, and outputs it to the monitor 300. Thereby, the user can accurately perform the inspection through the image displayed on the display screen of the monitor 300. The image processing unit 220 outputs an image, the information of the result of the quantification process, and the color map image to the printer 400 as necessary.

[0038] The processor 200 is connected to the server 600 via the NIC (Network Interface Card) 210 and the network 500. The processor 200 can download information related to the inspection by the endoscope (for example, the electronic medical record information of the patient and the information of the operator) from the server 600. The downloaded information is displayed, for example, on the display screen of the monitor 300 or the operation panel 208. In addition, the processor 200 can save the inspection result in the server 600 by uploading the inspection result by the endoscope 100 to the server 600. The endoscope 100 shown in FIGS. 1 and 2 is an example in which the imaging element 108 is provided at the distal end portion 132, but the distal end portion 132 may be configured to be provided with an ultrasonic vibrator together with the imaging element 108. In this case, the endoscope cable 140 is provided with a transmission line for transmitting a signal from the ultrasonic vibrator as an individual cable.

[0039] Within such a universal tube 128 and a flexible cable 130 of the endoscope 100, an endoscope cable 140 is provided to electrically connect between a distal end portion 132 of the endoscope inserted into the body cavity and a connector 110 at the rear end portion of the endoscope 100 connected to the processor 200. In FIG. 2, the endoscope cable 140 includes two transmission lines indicated by two solid arrow lines connecting the driver signal processing circuit 112 and the imaging element 108, and one transmission line for transmitting a light source control signal connecting the light source control circuit 116 and the LED light source 102. FIG. 2 shows a form in which the endoscope cable 140 includes three transmission lines as individual cables for simplicity, but may include a plurality of four or more individual cables.

[0040] FIG. 3 is a diagram for explaining an example of the endoscope cable 140. The endoscope cable 140 includes a plurality of individual cables. In FIG. 3, it includes six individual cables 142 to 152. The endoscope cable 140 includes an overall shield portion 160 composed of a group of metal wires having an electric shielding function surrounding the entire individual cables 142 to 152, and cable cores 142A to 152A each composed of a group of metal wires in each of the individual cables 142 to 152. The group of metal wires in the overall shield portion 160 is composed of a combination of a plurality of types of metal wires having different compositions from each other. Note that the surface of the metal wire may be plated with tin, silver, or the like. In the example shown in FIG. 3, the overall shield portion 160 is composed of a combination of a plurality of types of metal wires having different compositions from each other in the group of metal wires. In another example, the cable cores 142A to 152A can be composed of a combination of a plurality of types of metal wires having different compositions from each other in the group of metal wires, and at least one of the overall shield portion 160 and the cable cores 142A to 152A can also be composed of a combination of a plurality of types of metal wires having different compositions from each other in the group of metal wires.

[0041] In the example shown in FIG. 3, in the overall shield portion 160, a group of metal strands having a circular cross-section are arranged along the circumference. Specifically, the metal strands with white cross-sections and the metal strands with gray cross-sections are alternately arranged so as to be adjacent to each other along the circumference. That is, in the overall shield portion 160, two types of metal strands are arranged in order.

[0042] FIG. 4 is a diagram for explaining another example of the endoscope cable 140. In the example shown in FIG. 4, similar to FIG. 3, in the overall shield portion 160, a group of metal strands having a circular cross-section are arranged along the circumference. However, the types of metal strands are the metal strands with white cross-sections, the metal strands with light gray cross-sections, and the metal strands with dark gray cross-sections arranged in order. That is, in the overall shield portion 160, three types of metal strands are arranged in order.

[0043] FIG. 5 is a diagram for explaining another example of the endoscope cable 140. In the example shown in FIG. 5, similar to FIG. 3, in the overall shield portion 160, a group of metal strands having a circular cross-section are arranged along the circumference, and the types of metal strands are the metal strands with white cross-sections and the metal strands with gray cross-sections arranged in order. Such two types of metal strands are also arranged in the metal strand groups of the individual cable shield portions 142B, 144B, and 146B of the individual cables 142, 144, and 146 in addition to the overall shield portion 160.

[0044] FIG. 6 is a diagram for explaining yet another example of the endoscope cable 140. In the example shown in FIG. 6, similar to FIG. 3, in the overall shield portion 160, a group of metal strands having a circular cross-section are arranged along the circumference, and the types of metal strands are the metal strands with white cross-sections and the metal strands with gray cross-sections arranged in order. Such two types of metal strands are also arranged in the cable cores 142A to 152A of the individual cables 142 to 152 and the metal strand groups of the individual cable shield portions 142B to 146B in addition to the overall shield portion 160.

[0045] As described above, in this embodiment, a plurality of types of metal wires are arranged in the overall shield portion 160 and / or the cable core wires 142A to 152A of the individual cables 142 to 152. That is, the metal wire group in at least one of the overall shield portion 160 and the cable core wires 142A to 152A is configured by combining a plurality of types of metal wires having different compositions from each other. By configuring the endoscope cable 140 using such a metal wire group, it is possible to achieve both the durability of the endoscope cable and the ease of work such as connection work. Generally, between different types of metal wires, the durability and the repulsive force against deformation are often different. In a metal wire with excellent durability, since the repulsive force against deformation is large, when trying to expose the cable core wires 142A to 152A at the end of the endoscope cable 140 and twist the metal wires and connect them to the terminals of the imaging device 108 by soldering or the like, the connection work becomes difficult due to the large repulsive force, and the efficiency of the connection work may decrease. On the other hand, in a metal wire with a small repulsive force against deformation, the efficiency of the above connection work is improved, but the metal wire is likely to break due to handling such as twisting, bending, or pulling the endoscope cable 130, that is, the durability is low. For this reason, in the metal wire group in at least one of the overall shield portion 160 and the cable core wires 142A to 152A, a plurality of types of metal wires having different compositions from each other are combined.

[0046] Further, at least one of the plurality of individual cables 142 to 152 preferably includes an individual cable shield portion configured by a metal wire group having an electric shielding function so as to surround the cable core wire. An individual cable having such a configuration can block electromagnetic waves from the outside and suppress the leakage of electromagnetic waves generated by the high-frequency signal flowing through the cable core wire to the outside. It is preferable that the metal wire group in such an individual cable shield portion is configured by combining a plurality of types of metal wires having different compositions from each other. Thereby, it is possible to achieve both the durability of the endoscope cable and the ease of connection work.

[0047] In the above example, a plurality of types of metal wire elements are combined in one group of metal wire elements. However, among the overall shield portion 160, the cable core wires 142A to 152A, and at least two of the individual cable shield portions 142B, 144B, and 146B, the groups of metal wire elements are configured by combining a plurality of types of metal wire elements with different compositions. The types of metal wire elements used in at least two groups of metal wire elements are the same, but the ratio of the number of uses of the plurality of types of metal wire elements used within the group of metal wire elements may be different between at least two groups of metal wire elements. By changing the ratio of the number of uses of the plurality of types of metal wire elements, while adjusting the ratio of the number of uses according to the characteristics (for example, conductivity, electromagnetic shielding property) required for each of the cable core wires 142A to 152A of the individual cables 142 to 152, the individual cable shield portions 142B, 144B, 146B, or the overall shield portion 160, it is possible to achieve both durability and connection work efficiency in the endoscope cable 140.

[0048] Among the overall shield portion 160 and at least one of the individual cables 142 to 152, it is preferable that the group of metal wire elements has a plurality of types of metal wire elements arranged along the circumference of the endoscope cable or along the circumference of the individual cable so as to repeat in a predetermined order. In the case of two types of metal wire elements as shown in FIGS. 3, 5, and 6, they are arranged alternately. Also, in the case of three types of metal wire elements as shown in FIG. 4, the three types of metal wire elements are repeatedly arranged in order. When changing the ratio of the number of uses of the above metal wire elements, it is preferable that different types of metal wire elements are regularly repeated and arranged.

[0049] Among the entire shield part 160, the cable core wires 142A to 152A, and at least two of the individual cable shield parts 142B, 144B, and 146B, the combination of the types of metal strands used for the metal strand groups may be different. For example, in the metal strand group in the entire shield part 160, it is a combination of metal strand A and metal strand B, while in one metal strand group of the cable core wires 142A to 152A, it is a combination of metal strand A and metal strand C. Also, between at least two metal strand groups, the number of types of metal strands used for the metal strand groups may be different.

[0050] Although the compositions are different among multiple types of metal strands, "the compositions are different" means that the metal compositions are different. For example, when the metal strand is made of an alloy, it includes that the metal components constituting the alloy are different, and even if the same metal components are included, the composition ratios are different. Also, even if the metal components and the composition ratios are the same, it is possible to create strands with different physical properties due to changes in the crystal structure by metal production conditions (such as heat treatment). "The compositions are different" includes those in which the composition ratios are the same but the crystal structures change and the physical properties are different.

[0051] According to one embodiment, it is preferable that the multiple types of metal strands include at least a strand made of soft copper (conforming to JIS C3102 - 1984 or JIS C3152 - 1984) and a strand made of a copper alloy having a Young's modulus larger than that of the soft copper strand. The soft copper strand has high conductivity and a small repulsive force against deformation, so it has excellent electrical characteristics as the cable core wires 142A to 152A and improves the efficiency of connection work. However, it is easily broken by twisting, bending, or pulling the endoscope cable 140. That is, the durability is low. In contrast, various copper alloy strands generally have a lower conductivity than the soft copper strand and a large repulsive force against deformation. Therefore, the electrical characteristics as the cable core wires 142A to 152A are low, and the efficiency of connection work is also low, while the durability is excellent. For this reason, by combining a soft copper strand and a copper alloy strand having a Young's modulus larger than that of the soft copper strand and using them in one metal strand group, it is possible to achieve both durability and the efficiency of connection work. The copper alloy stranded wire preferably includes a plurality of types of copper alloy stranded wires having different metal compositions. To have different metal compositions, as described above, in addition to the case where the compositional components are different, even when the compositional components are the same, the case where the composition ratios are different is also included.

[0052] It is preferable that the plurality of types of metal stranded wires having different compositions have at least one characteristic different from each other, such as conductivity (JIS C3002) and Young's modulus. Thereby, while satisfying the electrical characteristics required for the individual cables 142 to 152, it is possible to achieve both durability and connection work efficiency in the endoscope cable 140.

[0053] Note that the metal stranded wires of the overall shield portion 160 and the individual cable shield portions 142B to 146B may be configured in a spiral structure or a braided structure.

[0054] When the distal end portion 132 of the endoscope 100 is inserted into the body cavity of a human body, the endoscope cable 140 is subjected to stresses such as bending, twisting, or pulling so as to follow the bent tube in the body cavity. Since the endoscope cable 140 is subjected to the above stresses every time the endoscope 100 is used, as described above, the endoscope cable 140 is required to have excellent durability. The endoscope 100 is not the same regardless of the site in the body cavity to be inspected, but is preferably selected from a plurality of endoscopes according to the use conditions including the site in the body cavity to be inserted and the operation content of the endoscope 100. Therefore, it is preferable that the endoscope system 1 includes a plurality of endoscopes 100 that can be connected to the endoscope processor 200. Therefore, in this case, the endoscope 100 used is an endoscope selected from a group of endoscopes that can be connected to the processor 200 according to the use conditions including the inspection site in the body cavity and the operation content of the endoscope 100. At this time, it is preferable that at least one of the combination of the types of metal wires used for the endoscope cable 140 and the ratio of the number of uses of a plurality of types of metal wires used within the metal wire group is different according to the above usage conditions in at least two of the endoscope groups. Since the stress received by the endoscope cable 140 varies depending on the usage conditions, it is only necessary to ensure durability according to this stress. For example, when imaging a site with many bends such as the large intestine, an endoscope cable 140 with excellent durability is used. On the other hand, in the case of the endoscope 100 for performing ultrasonic diagnosis, since the output signal level is small, the electrical characteristics of the endoscope cable 140 are the most prioritized characteristics. In this case, a metal wire with low conductivity is used for the cable core wires 142A to 152A, or an endoscope cable 140 with excellent electromagnetic shielding properties is used in order not to be affected by external noise.

[0055] As described above, the endoscope and the endoscope system of the present invention have been described in detail. However, the present invention is not limited to the above embodiments, and it goes without saying that various improvements and modifications may be made without departing from the gist of the present invention.

Explanation of Reference Numerals

[0056] 1 Electronic endoscope system 100 Endoscope 102 LED light source 104 Orientation lens 106 Objective lens 108 Image sensor 108a Cut filter 108b Color filter 110 Connector 112 Driver signal processing circuit 114 Memory 116 Light source control circuit 120 Operation unit 122 Bending operation knob 124 Operation button 126 Forceps insertion port 128 Universal tube 130 Flexible cable 140 Endoscope cable 142, 144, 146, 148, 150, 152 individual cables 142A, 144A, 146A, 148A, 150A, 152A cable cores 142B, 144B, 146B individual cable shield parts 160 overall shield part 200 processor 202 system controller 204 memory 206 timing controller 208 operation panel 210 NIC 220 image processing unit 300 monitor 400 printer 500 network 600 server

Claims

1. An endoscope having an endoscope cable that electrically connects between a distal end portion of an endoscope inserted into a body cavity and a connector at a rear end portion of the endoscope that connects to an endoscope processor, wherein the endoscope cable includes a plurality of individual cables, and includes an overall shield portion composed of a first group of metal strands having an electrical shielding function surrounding the plurality of individual cables, and cable core wires composed of a second group of metal strands in each of the individual cables, wherein the second group of metal strands is composed of a combination of a plurality of types of metal strands having different compositions and different durability or resilience against deformation, characterized in that it is an endoscope.

2. The endoscope according to claim 1, wherein at least one of the plurality of individual cables includes an individual cable shield portion composed of a third group of metal strands having an electrical shielding function surrounding the cable core wire.

3. The endoscope according to claim 2, wherein the third group of metal strands is composed of a combination of a plurality of types of metal strands having different compositions.

4. The second group of metal strands and either the first group of metal strands or the third group of metal strands are composed of a combination of a plurality of types of metal strands having different compositions, wherein the types of metal strands used in the second group of metal strands and either the first group of metal strands or the third group of metal strands are the same, but the ratio of the number of uses of the plurality of types of metal strands used within the second group of metal strands is different from either the first group of metal strands or the third group of metal strands, The endoscope according to claim 2 or 3.

5. The endoscope according to any one of claims 2 to 4, wherein in the third group of metal strands, the plurality of types of metal strands are arranged along the circumference of the individual cable so as to repeat in a predetermined order.

6. The endoscope according to any one of claims 1 to 5, wherein in the first group of metal strands, the plurality of types of metal strands are arranged along the circumference of the endoscope cable so as to repeat in a predetermined order.

7. An endoscope having an endoscope cable that electrically connects between a distal end portion of an endoscope inserted into a body cavity and a connector at a rear end portion of the endoscope that connects to an endoscope processor, The endoscope cable includes a plurality of individual cables, and includes an overall shield portion composed of a first group of metal strands having an electric shielding function surrounding the plurality of individual cables as a whole, and a cable core wire composed of a second group of metal strands in each of the individual cables. At least one of the plurality of individual cables includes an individual cable shield portion composed of a third group of metal strands having an electric shielding function so as to surround the periphery of the cable core wire. The second group of metal strands and either the first group of metal strands or the third group of metal strands are composed of a plurality of types of metal strands having different compositions from each other, and a plurality of types of metal strands having different durability or repulsive forces against deformation are combined. An endoscope characterized in that the combination of the types of metal strands is different between the second group of metal strands and either the first group of metal strands or the third group of metal strands.

8. The endoscope according to any one of claims 1 to 7, wherein the metal compositions are different among the plurality of types of metal strands.

9. The endoscope according to any one of claims 1 to 8, wherein the plurality of types of metal strands at least include a strand made of soft copper (conforming to JIS C3102-1984 or JIS C3152-1984) and a strand made of a copper alloy having a Young's modulus larger than that of the soft copper strand.

10. The endoscope according to claim 9, wherein the copper alloy strands include a plurality of types of copper alloy strands having different metal compositions.

11. The endoscope according to any one of claims 1 to 10, wherein at least one of the conductivity (JIS C3002) and the Young's modulus has different characteristics among the plurality of types of metal strands having different compositions.

12. An endoscope system comprising the endoscope according to any one of claims 1 to 11 and an endoscope processor connected to the endoscope via the connector, outputting an instruction signal to the endoscope, and receiving and processing a signal output from the endoscope. The endoscope is an endoscope selected from a group of endoscopes connectable to the endoscope processor according to the use conditions including the site in the body cavity into which the endoscope is inserted and the operation content of the endoscope. In at least two of the endoscope groups, at least one of a combination of types of metal wires used for the endoscope cable and a ratio of the number of uses of a plurality of types of metal wires used within the second metal wire group is different according to the usage conditions, and an endoscope system characterized by this.

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