JP5144350B2 - Shielded wire behavior prediction method, shielded wire behavior prediction system, shielded cable manufacturing method, shielded cable device - Google Patents

Description

  The present invention relates to a method for predicting shielded wire behavior of a shielded cable, a system for predicting shielded wire behavior, a method for manufacturing a shielded cable, and a device with a shielded cable.

A shielded cable is used for electrical wiring, and is an electric wire in which a shield layer is provided on the outer periphery of a conducting wire (core wire) via an insulating layer in order to cut electromagnetic waves from the outside and electromagnetic waves emitted to the outside. .
As a shield layer of a shielded cable, for example, there is one having a braided structure as disclosed in Patent Document 1 (hereinafter referred to as “braided shield layer”). The braided shield layer is formed by braiding so that a bundle of metal shield wires (element wires) intersect at a predetermined braid angle. The outer periphery of the braided shield layer is covered with an insulating sheath.

Patent Document 2 discloses a technique for predicting the bending life of an electric wire bundle. In this technique, the amount of strain change of the wire bundle accompanying bending deformation of the wire bundle is calculated, and the bending life of the wire bundle is predicted based on the amount of strain change.
JP 2006-164754 A JP 2002-260460 A

Conventionally, there has been no method for appropriately predicting the life of a shielded cable having a braided shield layer.
Here, in order to predict the bending life of the shielded cable, it is conceivable to calculate the “strain change amount” of the cable accompanying the bending deformation of the shielded cable as in Patent Document 2.
However, according to the study by the present inventors, in the case of a shielded cable having a braided shield layer, the correlation between the cable distortion accompanying the bending deformation of the shielded cable and the life of the shielded cable is small, and attention is paid to the distortion of the cable. Even so, it turned out to be difficult to properly predict the life.

  Therefore, an object of the present invention is to obtain a new technique suitable for predicting the life of a shielded cable having a braided shield layer, or a device with a shielded cable having excellent durability against bending.

  In view of the first aspect, the present invention relates to the behavior of the shielded wire accompanying bending of a shielded cable having a braided shield layer configured so that a plurality of shield wires intersect with each other and an insulating sheath covering the braided shield layer. Predicting a braided structure of the braided shield layer by a computer, inputting a braided degree of the shield cable by a computer, and inputting the braided structure Based on the parameters, the computer calculates the braided structure of the shielded wire when the shielded cable is in a straight state, and the braided structure of the shielded wire when the shielded cable is in a straight state. Before bending the shielded cable based on the bending degree Based on the bending state calculation process in which the computer calculates the braided structure of the shielded wire and the braided structure of the shielded wire when the shielded cable is bent, the first friction amount defined as (1) below and / or And a friction amount calculation step in which a computer calculates a second friction amount defined as described in (2) below.

here,
(1) The first friction amount refers to a value indicating a sliding amount in which shield wires intersecting each other slide with each other as the shield cable is bent.
(2) The second friction amount is a value indicating a sliding amount with which the shield wire slides with respect to the insulating sheath as the shield cable is bent.

  In the case of a shielded cable having a braided shield layer, the shield wire that constitutes the braided shield layer is in relation to other shield wires or insulated sheath wires as the shield cable is bent, rather than the “distortion” that occurs when the shield cable is bent. The present inventors have found that "friction" during sliding greatly affects the life of the shielded cable.

Therefore, it is optimal for predicting the life of the shielded cable to predict the friction amount of the shielded wire accompanying the bending of the shielded cable as the behavior of the shielded wire accompanying the bending of the shielded cable.
And according to the said invention, since the said 1st friction amount and / or 2nd friction amount are calculated according to a braided structure, it is possible to determine a shield cable lifetime appropriately.

  In the friction amount calculating step, a position where a point on the shield wire that is an intersection of the shield wires when the shield cable is in a straight state is obtained after the shield cable is bent is obtained, and the first friction is calculated based on the position. It is preferable to calculate the amount and / or the second friction amount. In this case, it is possible to calculate the amount of friction when the shielded cable is bent from the straight state.

  The first friction amount exists apart after bending the shielded cable when viewed at each point on each shielded wire that forms one intersection of shielded wires that intersect when the shielded cable is in a straight line state. It is preferable that the distance is a distance between the points. In this case, the first friction distance is calculated as a distance where each point constituting the shield wire intersection in the state immediately before the shield cable is separated.

  In addition, the second amount of friction is such that the point on the shield wire that constitutes one intersection of the shielded wires that intersect when the shielded cable is in a straight state is the intersection of the shielded wires as the shield cable is bent. It is preferable that the amount of movement in the moving direction. In this case, the second friction distance is calculated as the distance that the points constituting the intersection move in the movement direction of the intersection.

  It is preferable to further include a step of generating and outputting an image showing the braided structure of the shielded wire when the shielded cable is bent. In this case, it becomes easy for the user to visually understand the change in the braided structure associated with the shielded cable.

  It is preferable that the method further includes a determination step of determining the quality of the braided structure of the braided shield layer by comparing the first friction amount and / or the second friction amount with a reference value. In this case, the quality of the braided structure can be automatically determined.

From another point of view, the present invention predicts the behavior of the shielded wire accompanying bending of a shielded cable having a braided shield layer configured so that a plurality of shield wires cross each other and an insulating sheath covering the braided shield layer. The system includes a parameter input unit that receives an input of a braided structure parameter that defines a braided structure of the braided shield layer, a bending degree input unit that receives an input of a bending degree of the shielded cable, and the input braided structure parameter. Based on the linear state calculation unit that the computer calculates the braided structure of the shielded wire when the shielded cable is in a straight state, the braided structure of the shielded wire when the shielded cable is in a linear state, and the input Calculate the braided structure of the shielded wire when the shielded cable is bent based on the bending degree Based on the bending state calculation unit and the braided structure of the shielded wire when the shield cable is bent, the first friction amount defined as (1) below and / or (2) below is defined. And a friction amount calculation unit for calculating a second friction amount, and a shield wire behavior prediction system.
(1) The first friction amount refers to a value indicating a sliding amount in which shield wires intersecting each other slide with each other as the shield cable is bent.
(2) The second friction amount is a value indicating a sliding amount with which the shield wire slides with respect to the insulating sheath as the shield cable is bent.

  Also in the above system, since the first friction amount and / or the second friction amount is calculated according to the braided structure, it is possible to appropriately determine the life of the shielded cable.

From another viewpoint, the present invention is a shielded cable that is repeatedly bent at the time of use, and includes a braided shield layer configured so that a plurality of shield wires intersect with each other, and a shielded cable covering the braided shield layer, A braided structure determining step for determining a braided structure of the braided shield layer, and a braided shield layer is formed by braiding the shield wire in accordance with the braided structure determined in the braided angle determining step. A braided shield layer forming step, wherein the braided structure determining step includes a candidate selecting step for selecting a braided structure candidate and a first braided structure candidate defined as shown in (A) below: Friction amount and / or a friction amount calculation step for calculating a second friction amount defined as (B) below, and the friction amount calculation step A determination step for determining the quality of the braided structure by comparing the first friction amount and / or the second friction amount with a reference value. In the braided shield layer forming step, it is determined that the determination step is good. According to another aspect of the present invention, there is provided a shielded cable manufacturing method characterized in that a braided shield layer having a braided structure suitable for the bending degree of a shielded cable in use is obtained by braiding shielded wires according to the braided structure.
(A) The first friction amount indicates a sliding amount in which shield wires intersecting each other slide with each other when the shield cable having the braided shield layer having the braided structure selected in the candidate selecting step is used. Value.
(B) The second friction amount is a sliding amount at which the shield wire slides with respect to the insulating sheath in accordance with repeated bending when using a shielded cable having a braided shield layer having a braided structure selected in the candidate selecting step. A value indicating the amount of movement.

  According to the manufacturing method, a shielded cable having a braided shield layer having a braided structure suitable for the degree of bending during use can be obtained.

  From another viewpoint, the present invention is an apparatus with a shielded cable in which a shield cable is attached to the apparatus main body, wherein the apparatus main body includes a bending portion that repeatedly performs a bending operation, and the shield cable includes a plurality of shields. A braided shield layer configured to intersect the wires and an insulating sheath covering the braided shield layer, and the shielded cable is configured to repeatedly bend as the bent portion repeatedly bends. The braided shield layer of the shield cable attached to the apparatus main body further has a sliding amount when the shield wire repeatedly slides with respect to the insulating sheath in a bending that repeatedly occurs as the bending portion repeatedly bends. With a shielded cable, characterized by a braided structure of 0.53 mm or less It is a device.

  According to the above apparatus, since the sliding amount (amount that the shield wire slides with respect to the insulating sheath) in bending caused by the bending operation repeatedly performed in the bending portion of the apparatus main body is 0.53 mm or less, A device is obtained in which the shielded cable is not easily damaged even if it is repeatedly bent.

According to the method for predicting shielded wire behavior and the system for predicting shielded wire behavior according to the present invention, it is possible to calculate the first friction amount and / or the second friction amount, which are important elements of the shield cable life.
Further, according to the shielded cable manufacturing method and the shielded cable device according to the present invention, a shielded cable or device having appropriate durability against a predetermined bending can be obtained.

Embodiments of the present invention will be described below with reference to the drawings.
[Configuration of shield wire behavior prediction system]
FIG. 1 shows the configuration of a shielded wire behavior prediction system included in a shielded cable. The system 10 is input by an input device 11 including a keyboard and a mouse, an output device 12 including a display and a printer, a storage unit 13 including a hard disk for storing various information, and the input device 12. A data processing unit 20 that performs processing for predicting the behavior of the shielded wire based on various data (calculating the friction amount) is provided.

  The input / output devices 11 and 12 receive braid structure parameters (details will be described later) and the degree of bending, and output the calculation results by the data processing unit 20.

  Functionally, the data processing unit 20 includes a straight line state calculation unit 21, a bending state calculation unit 22, a friction amount calculation unit 23, a determination unit 24, and an image output unit 25. The functions of these units 21 to 25 are realized by a data processing unit (calculation unit) executing a computer program recorded in the storage unit 13 so as to be executable. Details of the functions of the units 21 to 25 will be described later.

[Structure of shielded cable]
FIG. 2 shows the structure of a shielded cable that is a target for predicting the shield wire behavior by the system 10.
The illustrated shielded cable is formed by shielding one or more core wires (conductor wires) 101 with a shield layer 103 having a braided structure through an inner insulating layer 102. The outer peripheral side of the shield layer 103 is covered with an insulating sheath 104.

The shield layer 103 is configured as a braided shield layer formed by braiding conductive (metal) shield wires (wires) so as to have a predetermined braid structure. More specifically, as shown in FIG. 3, the braided shield layer is formed by braiding shield wire bundles 103a and 103b in which a plurality of shield wires are bundled into a net shape. The shield wire bundles 103a and 103b are knitted so that a plurality of bundles intersect each other with a predetermined braid angle θ, and become a braided shield layer having a predetermined shield diameter (diameter in FIG. 3).
The plurality of shield wire bundles 103a and 103b include a shield wire bundle 103a having one direction and a plurality of shield wire bundles 103b having the other direction. The crossing angle of 103b is knitted so as to be 2 × θ.
In the present embodiment, the braid angle θ refers to the angle in the longitudinal direction of the shield wire (shield bundle) with respect to the longitudinal direction of the shield layer (shield cable) that is linear and not bent.

[Display screen of shield wire behavior prediction system]
FIG. 4 shows a screen D displayed on the output device (display) 12 of the system 10. On this screen D, it is possible to input various data and output calculation results by the data processing unit 20.
The screen D in FIG. 4 has a numerical value display part D1, a bending radius input part (bending degree input part) D2, a shield layer appearance display part D3, D4, a curvature display part D5, and a friction distance display part D6.

  The numerical value display part D1 is for displaying numerical data related to the cable (shield layer), and includes a bending radius (bending degree input part), a shield diameter, a shield angle (braiding angle), Δ curvature (neutral), and Δ curvature. (Inner side), Δ curvature (outer side), x-axis rotation angle, y-axis rotation angle, friction distance (line / line), friction distance (line / sheath), and R / P are displayed.

  Among the items of the numerical value display section D1, the user can input numerical values from the input device 11 for “bending radius”, “shield diameter”, and “shield angle” (braided angle). In “bending radius”, “bending radius” R can be input as the bending degree of the shielded cable. The bending degree is not limited to a bending radius (curvature radius), and may be a curvature.

In addition, in the “shield diameter”, the outer diameter of the shield layer can be input. Furthermore, the braiding angle can be input in the “shield angle”. Here, the shield diameter and the shield angle are braid structure parameters that determine the braid structure of the shield layer. The braided structure parameter may include a shield pitch in addition to the shield diameter and the shield angle. Further, the braided structure parameter may be a shield diameter and a shield pit instead of the shield diameter and the shield angle.
Note that the “bending radius” is not only to directly input a numerical value to the numerical value display portion D1, but also to adjust the numerical value of the bending radius by clicking each button of the bending radius input portion (bending degree input portion) D2. You can also.

Among each item of the numerical value display part D1, “Δ curvature (neutral)” displays the amount of curvature change (curvature differential value) of the shield wire (shield wire bundle) at the radial center position of the shield cable.
“Δ Curvature (inner side)” indicates the amount of curvature change (curvature differential value) of the shield wire (shield wire bundle) on the inner side of the bent shield cable.
“Δ Curvature (Outside)” indicates the amount of change in curvature (differential value of curvature) of the shielded wire (shielded wire bundle) on the outside of the bent shielded cable.

Among the items of the numerical value display part D1, “x-axis rotation angle” indicates the rotation angle in the x-axis direction in the first appearance display part D3, and “y-axis rotation angle” indicates the display part D3. This shows the rotation angle in the y-axis direction.
The “friction distance (line / line)” is for displaying a calculated “first friction amount”, which will be described later, and the “friction distance (line / sheath)” is calculated, as described below, “second”. This is for displaying the “friction amount”.
“R / P” is for displaying a value obtained by dividing the bending radius R by the pitch P of the shield layer. The pitch P may be input or calculated from the shield diameter and the braiding angle.

As the shield layer appearance display portions D3 and D4, a first appearance display portion D3 that displays a schematic three-dimensional appearance of the shield layer and a second appearance display portion D4 that displays a typical two-dimensional appearance of the shield layer are provided. It has been.
The first appearance display section D3 schematically displays the three-dimensional appearance of the braid structure defined by the input shield diameter and shield angle (braid angle) at the input bending radius (bending degree). is there. In the first appearance display section D3, for the sake of visual and easy-to-understand display, the center line C1 of the shielded cable, the line S1 indicating the shield wire in one direction (shield wire bundle 103a), the shield wire in the one direction (shield) Three lines S2 indicating a shield line (shield wire bundle 103b) in another direction intersecting with the wire bundle 103a) are displayed as an image showing the braided structure of the shield layer 103.

  In the first appearance display portion D3, an image in which the shield cable center line C is bent according to the input bending radius is displayed, and the lines S1 and S2 indicating the shield line are deformed according to the bending of the shield cable. Show the state. With this first appearance display portion D3, the user can visually grasp the bending state of the shielded wire when the shielded cable is bent at the input bending radius (bending degree). .

  The display angle (x-axis rotation angle and y-axis rotation angle) in the first appearance display unit D3 can be adjusted by clicking each button of the display angle operation unit D3-1.

  The second appearance display unit D3 is a two-dimensional display of the center line C1 and the lines S1 and S2 displayed on the first appearance display unit D3. The second appearance display unit D3 also provides a shielded cable. The user can visually grasp how the shield wire bends when bent at a certain bending radius (degree of bending).

  The curvature display part D5 expresses the bending state of the shielded wire when the shielded cable is bent at the input bending radius, by the curvature of the shielded wire in the axial direction of the shielded cable. The curvature display portion D5 allows the user to grasp the degree of curvature of the shielded wire at each position of the shielded cable when the shielded cable is bent.

  The friction distance display part D6 illustrates the friction distance (friction amount) when the shield cable is bent with the input bending radius. The friction distance (friction amount) will be described later. The friction distance display portion D6 allows the user to visually grasp the degree of the friction distance when the shield cable is bent.

[Processing procedure in shielded wire behavior prediction system]
FIG. 5 shows a processing procedure in the shielded wire behavior prediction system 10. First, the user inputs a braided structure parameter that defines the braided shield layer 103 of the shielded cable C that is the target of behavior prediction from the screen D shown in FIG. 4 (step S1).
In the present embodiment, the shield diameter (outer diameter) and the braid angle θ are input as the braid structure parameters.
As shown in FIG. 6A, the braided structure parameter is a parameter that determines the structure of the braided shield layer 103 when the shielded cable C is not bent and is in a straight state (straight). The braiding angle θ can also be referred to as the inclination angle of the shield wire with respect to the shield cable center line C in a straight line state.
Note that a pitch may be input as the braid structure parameter.

When the system 10 receives the input of the braided structure parameter (step S1), the data (two-dimensional) indicates the state (braided structure) of the shielded wires S1, S2 of the braided shield layer in the straight shielded cable C according to the braided structure parameter. Data and three-dimensional data) are generated (function of the straight line state calculation unit), and an image showing the braided structure is displayed on the appearance display units D3 and D4 of the screen D (step S2; function of the image output unit).
Further, the system 10 calculates the curvature of the shielded wire in the straight shielded cable C at each point in the shielded cable axial direction, and displays it on the curvature display portion D5. Furthermore, the system 10 displays a diagram showing the friction distance (here, 0) of the shield wire in the straight shielded cable C on the friction distance display unit D6.

Here, the data indicating the state of the shield lines S1, S2, etc. is represented as a set of points obtained by finely dividing the shield lines S1, S2, etc.
That is, as shown in FIG. 6A, the braided structure of the shield layer 103 is schematically represented by shield layer outer diameter lines X1 and X2 and two-direction shield lines (representative lines) S1 and S2. The And each line X1, X2, S1, S2 of Fig.6 (a) can be produced | generated based on a shield diameter and braiding angle (theta) (or pitch).
The system 10 stores the lines X1, X2, S1, and S2 in FIG. 6A in the storage unit 13 as data including a set of points obtained by finely dividing the lines X1, X2, S1, and S2.

  Subsequently, when the system 10 receives an input of a bending diameter (bending radius; bending degree) (step S3), the system 10 performs predetermined processing on data indicating the state of the linear shield layer based on the input bending diameter. The data indicating the braided structure of the shield layer when the shield cable C is bent with the input bending diameter is generated (step S4; function of the bending state calculation unit).

  Specifically, step S4 is a process of rearranging the points constituting the lines X1, X2, S1, and S2 radially as viewed from the bending center O determined by the inputted bending diameter, as shown in FIG. 6B. It is. That is, in the straight state of FIG. 6A, the points where the intersecting lines S1, S2 intersect with the outer diameter lines X1, X2 are A, B, C, D as shown in FIG. 6A. As shown in FIG. 6B, the system 10 sets the lines X1, X2, S1, and S2 so that A ′, C′O, and D′ B′O are straight lines with the bending center O as the center. Data in which the constituent points are rearranged is generated, and the data is stored in the storage unit 13.

By the processing in step S4, a braided structure when the shield cable is bent with the input bending diameter (bending degree) is calculated. The image showing the braided structure when the shielded cable is bent is displayed on the appearance display parts D3 and D4, similarly to the braided structure of the straight shielded cable (step S5; function of the image output part).
Further, the system 10 calculates the curvature of the shielded wire when the shielded cable C is bent at each point in the shielded cable axial direction, and displays it on the curvature display portion D5.

  Furthermore, the system 10 generates an image indicating the amount of friction (friction distance) when the shielded cable C is bent, and displays the image on the friction distance display unit D6 as shown in FIG. In addition, the display content in the friction distance display part D6 is mentioned later.

Subsequent to step S5, the system 10 performs a process of calculating the first friction amount (first friction distance) and the second friction amount (second friction distance) (step S6; function of the friction amount calculation unit).
The first friction amount and the second friction amount are obtained as shown in FIG. That is, the first friction amount is calculated as a distance (separation distance) between the midpoint of A′B ′ and the midpoint of C′D ′ in the braided structure in which the shielded cable C is bent (see FIG. 6B). Is done. The second friction amount is calculated as the distance from the cable center line C1 between the midpoint of A′B ′ and the midpoint of C′D ′.

  The first friction amount calculated as described above has the following significance. That is, “the midpoint of A′B ′ and the midpoint of C′D ′” is a point that constitutes the intersection of two intersecting shield lines S1 and S2 in a straight shielded cable (see FIG. 6A). ), The point of the shield line S1 constituting this intersection is “the midpoint of A ′, B ′”, and the point of the shield line S2 constituting the intersection is “the midpoint of C′D ′”.

  When the shielded cable is bent, the points of the shield lines S1 and S2 constituting the intersection move away from each other as shown in FIG. When the points of the shield lines S1 and S2 move as shown in FIG. 7, the shield lines S1 and S2 cross each other, so that the shield lines S1 and S2 slide with each other and friction is generated. If the bending of the shield cable is repeated, the braided structure of the shield layer 103 repeatedly changes between the state shown in FIG. 6A and the state shown in FIG. When the 1 friction distance (first friction amount) is increased, the life of the shield layer 103 is shortened.

  In the present embodiment, the first friction distance is obtained as described above, but the first friction distance (as the first friction amount, for example, “intersection of shield lines S1 and S2” in FIG. 7 and “A You may obtain | require as distance between the "midpoint of" B "and / or the midpoint of C'D" ".

  The second friction amount calculated as described above has the following significance. That is, as described above, “the midpoint of A′B ′ and the midpoint of C′D ′” is a point that constitutes the intersection of two intersecting shield lines S1 and S2 in a straight shielded cable (FIG. 6). (See (a)), the point of the shield line S1 that constitutes this intersection is the “midpoint of A ′, B ′”, and the point of the shield line S2 that constitutes the intersection is the “midpoint of C′D ′” It is.

  When the shielded cable is bent, the points of the shield lines S1 and S2 constituting the intersection move away from each other as shown in FIG. When the points of the shield wires S1 and S2 move as shown in FIG. 7, the shield wires S1 and S2 are in contact with the insulating sheath 104 on the outer peripheral side. To generate friction. If the bending of the shield cable is repeated, the braided structure of the shield layer 103 repeatedly changes between the state of FIG. 6A and the state of FIG. As the amount of friction (second friction distance; second friction amount) increases, the life of the shield layer 103 is shortened.

  In the present embodiment shown in FIG. 7, the second friction amount is a point on the shield lines S1 and S2 that constitute one intersection of the shield lines that intersect when the shield cable is in a straight state (A ′, B ′ midpoint, C′D ′ midpoint) was calculated as the amount of movement in the direction (left-right direction in FIG. 7) in which the intersection of the shielded wires moves with the bending of the shield cable. The second friction amount may be calculated as a distance connecting the intersection of the shield lines S1 and S2 in the shielded cable C before bending and the intersection of the shield lines S1 and S2 in the shielded cable C after bending.

The calculated first friction amount (first friction distance) is displayed in the “friction distance (line / line)” column of the numerical value display section D1 shown in FIG. The calculated second friction amount (second friction distance) is displayed in the “friction distance (line / sheath)” field of the numerical value display section D1.
Furthermore, in order to make it easy to visually grasp the first friction amount and the second friction amount, the system 10 intersects the shield wires S1 and S2 when the shield cable C is straight with respect to the shield cable center line C1. Is displayed on the frictional distance display section D6 as to which position when the shielded cable C is bent.

Although only the display of the first friction amount and the second friction amount in FIG. 4 allows the user to determine whether the inputted braid structure parameter is appropriate, the system 10 automatically determines whether the braid structure parameter is good or bad. be able to.
That is, as shown in step S <b> 7 in FIG. 5, the system 10 performs a process of determining whether the input braid structure parameter is acceptable based on the calculated first friction amount and second friction amount.

In the pass / fail determination process, the first friction amount and the second friction amount are respectively compared with a reference value. If the friction amount is lower than the reference value, it is determined to be good, and if it exceeds the reference value, it is determined to be defective. The reference value for the first friction amount is set to 0.8 mm, for example, and the reference value for the second friction amount is set to 0.5 mm, for example.
In the determination process of step S7, it may be determined that both the first friction amount and the second friction amount are lower than the respective reference values, or a reference value corresponding to any one of the friction amounts is set. If it falls below, it may be determined as good.

  FIG. 8 and FIG. 9 show the result of actually performing millions of bending tests at various bending radii R on a large number of shielded cables having the seal assembly layers 103 having various shield diameters and various braiding angles. Is shown. FIG. 8 shows the relationship between the first friction amount and the maximum shield damage rate, and FIG. 9 shows the relationship between the second friction amount and the maximum shield damage rate.

As shown in FIGS. 8 and 9, when the friction amount (friction distance) is small, the shield maximum damage rate is small, and it is understood that the relationship between the friction amount and the damage rate is high.
Further, as shown in FIG. 8, with respect to the first friction amount, it can be seen that when the first friction amount is 0.8 mm or less, the damage rate is lower than when the first friction amount is larger than 0.8 mm. In addition, when the first friction amount is 0.8 mm, the damage rate may be slightly higher, but when the first friction amount is 0.7 mm or less, the damage rate is very low. That is, the first friction amount is preferably 0.8 mm or less, and more preferably 0.7 mm or less.

  The first friction amount is preferably as small as possible. However, if it is smaller than 0.1, the braiding angle becomes large, which leads to high raw material costs and high manufacturing costs.

  As shown in FIG. 9, regarding the second friction amount, when the second friction amount is 0.5 mm (strictly 0.53 mm) or less, the damage rate is lower than when the second friction amount is larger than 0.5 mm. I understand that Further, the second friction amount is preferably as small as possible, but if it is smaller than 0.10, the braiding angle becomes large, and the raw material cost and the manufacturing cost are high, so 0.10 or more is preferable, and 0.28 or more is further preferable.

  Further, as is apparent from FIGS. 8 and 9, according to the results measured by the present inventors, it has been found that the second friction amount has a higher correlation with cable damage than the first friction amount. did. Therefore, even if the first friction amount is somewhat large, the cable damage rate is low if the second friction amount is small. Therefore, in determining the quality of the braided structure, attention may be paid only to the second friction amount. Of course, it is possible to focus only on the first friction amount.

The above table shows the results of calculating the shield diameter and the braid angle θ at which the second friction amount is 0.5 mm or less using the system 10 for each use condition (bending radius R) of the shielded cable C. ing.
For example, when the shield diameter is 6 mm and the braid angle θ is 20 degrees, the second friction amount greatly exceeds 0.5 mm, and when the shield cable is repeatedly bent several million times with the bending radius R = 40 degrees, the shield is damaged. On the other hand, if the braid angle θ is 31 degrees (26 degrees or more) even with the shield diameter as it is, the friction distance is less than 0.5 mm, and cable damage is suppressed.

[Method of manufacturing shielded cable]
FIG. 11 shows a method for manufacturing a shielded cable using the present system 10. The manufacturing process of the shielded cable includes the manufacturing process of the braided shield layer 103, and FIG. 11 illustrates the manufacturing method focusing on the processes related to the braided shield layer 103.
Further, the shield cable manufacturing method here is for manufacturing a shielded cable to be attached to the apparatus main body 30 provided with a bending portion 31 that performs a bending operation as shown in FIG. That is, the apparatus main body 30 is a main body of an apparatus with a shielded cable such as a robot or a machine tool, and has a bending portion (joint portion) 31 that repeatedly performs a bending operation.
The shielded cable C is attached to the apparatus main body 30 so as to bend repeatedly as the bending portion 31 bends.

  Here, the bending degree (bending radius) of the shielded cable according to the bending operation of the bending portion 31 is different for each apparatus. In the shielded cable manufacturing method of the present embodiment, a shielded cable having the shield layer 103 set to an appropriate friction amount is obtained according to the shielded cable bend degree that differs for each device.

  Specifically, as shown in FIG. 11, a braid structure (braid structure parameter) candidate is selected (step S11). Of the braid structure parameters, the shield diameter is often inevitably determined depending on the structure required for the core wire 101 inside the shield layer 103, and therefore, here, the candidate (one or more) of the braid angle θ is mainly used. Is selected.

Then, based on the selected braid structure (braid structure parameter), the friction amount is calculated using the system 10 (step S12). The calculation process of the friction amount corresponds to steps S1 to S6 in FIG.
The degree of bending (bending diameter) used in calculating the amount of friction is the degree to which the shielded cable C bends (bending diameter) when the shielded cable C to be manufactured is bent at the bent portion of the apparatus main body 30. ) Is given.
In the friction amount calculation step here, only the second friction amount is calculated.

Subsequently, the second friction amount calculated in step S12 is compared with a predetermined reference value (0.53 mm), and quality determination is performed (step S13). If the second friction amount is below the reference value, the braid structure candidate selected in step S11 is determined to be good.
The reference value is not limited to 0.53 mm. Alternatively, the determination may be made using the first friction amount.

Subsequently, according to the braid structure (shield diameter and braid angle) determined to be good in step S13, the shield wire is knitted to obtain a braided shield layer (step S14).
Furthermore, final assembly such as covering the outer periphery of the braided shield layer 103 in which the core wire 101 or the like is held with the insulation shield 104 is performed, and the shield cable C for the apparatus body 30 having a predetermined degree of bending is obtained ( Step S15).

  Since this shielded cable C is configured to reduce the amount of friction (second amount of friction) when the shield galle portion is repeatedly bent along with the bending at the bent portion 30 of the apparatus main body 30, the shielded cable C is several million times. Even if it is repeatedly bent, it is difficult to damage and has a long life.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention.

It is a block diagram of a shield wire behavior prediction system. It is a perspective view which shows the structure of a shield cable. It is a top view which shows the structure of a braided shield layer. It is a screen displayed in a shield wire behavior system. It is a flowchart which shows the process sequence of a shield wire behavior prediction system. (A) is a schematic diagram of the structure of a shield layer when a shielded cable is straight, (b) is a schematic diagram of the structure of a shield layer when a shielded cable is bent. It is a schematic diagram explaining the 1st friction amount and the 2nd friction amount. It is a graph which shows the relationship between the 1st friction amount (a line / line friction distance) and a shield maximum damage rate. It is a graph which shows the relationship between a 2nd friction amount (a line | wire / sheath friction distance) and a shield maximum damage rate. It is a perspective view of an apparatus with a shield cable. It is a flowchart which shows a shield cable manufacturing process.

Explanation of symbols

C shield cable 10 shield wire behavior prediction system 21 linear state calculation unit 22 bending state calculation unit 23 friction amount calculation unit 24 determination unit 25 image output unit 30 apparatus main body 103 shield layer 104 insulating sheath

Claims (8)

A method for predicting, by a computer, the behavior of the shielded wire accompanying bending of a shielded cable having a braided shield layer configured to intersect a plurality of shield wires and an insulating sheath covering the braided shield layer,
A computer receiving input of a braided structure parameter that defines a braided structure of the braided shield layer;
A computer accepting an input of the bending degree of the shielded cable;
Based on the input braided structure parameter, a straight line state calculating step in which a computer calculates the braided structure of the shielded wire when the shielded cable is in a straight line state;
A bending state calculation step in which a computer calculates the braided structure of the shielded wire when the shielded cable is bent based on the braided structure of the shielded wire when the shielded cable is in a straight state and the input bending degree. When,
Based on the braided structure of the shielded wire when the shield cable is bent, a first friction amount defined as (1) below and / or a second friction amount defined as (2) below is calculated by the computer. A friction amount calculating step calculated by
A method for predicting the behavior of a shielded wire, comprising:
(1) The first friction amount refers to a value indicating a sliding amount in which shield wires intersecting each other slide with each other as the shield cable is bent.
(2) The second friction amount is a value indicating a sliding amount with which the shield wire slides with respect to the insulating sheath as the shield cable is bent.   In the friction amount calculating step, a position where a point on the shield wire that is an intersection of the shield wires when the shield cable is in a straight state is obtained after the shield cable is bent is obtained, and the first friction is calculated based on the position. The method for predicting shield wire behavior according to claim 1, wherein the amount and / or the second friction amount is calculated. The first friction amount exists apart after bending the shielded cable when viewed at each point on each shielded wire that forms one intersection of shielded wires that intersect when the shielded cable is in a straight line state. A separation distance between the points,
The second friction amount is such that the point on the shield line that constitutes one intersection of the shielded wires that intersect when the shielded cable is in a straight state moves the intersection of the shielded wires as the shield cable is bent. Is the amount moved in the direction of
The method for predicting shielded wire behavior according to claim 1 or 2, wherein:   The method for predicting shielded wire behavior according to any one of claims 1 to 3, further comprising a step of generating and outputting an image indicating a braided structure of the shielded wire when the shielded cable is bent.   5. The method according to claim 1, further comprising a determination step of determining the quality of the braided structure of the braided shield layer by comparing the first friction amount and / or the second friction amount with a reference value. The method for predicting the behavior of shielded wire according to crab. A system for predicting the behavior of the shielded wire accompanying bending of a shielded cable having a braided shield layer configured to intersect a plurality of shield wires and an insulating sheath covering the braided shield layer,
A parameter input unit for receiving an input of a braided structure parameter for determining a braided structure of the braided shield layer;
A bending degree input section for receiving an input of the bending degree of the shielded cable;
Based on the input braided structure parameters, a linear state calculation unit that a computer calculates the braided structure of the shielded wire when the shielded cable is in a straight state;
A bending state calculation unit that calculates the braided structure of the shielded wire when the shielded cable is bent based on the braided structure of the shielded wire when the shielded cable is in a straight state and the input bending degree;
Based on the braided structure of the shielded wire when the shield cable is bent, the first friction amount defined as (1) below and / or the second friction amount defined as (2) below is calculated. A friction amount calculation unit to perform,
Shield wire behavior prediction system characterized by having.
(1) The first friction amount refers to a value indicating a sliding amount in which shield wires intersecting each other slide with each other as the shield cable is bent.
(2) The second friction amount is a value indicating a sliding amount with which the shield wire slides with respect to the insulating sheath as the shield cable is bent. A shielded cable that is repeatedly bent at the time of use, and is a method of manufacturing a shielded cable having a braided shield layer configured to intersect a plurality of shield wires and an insulating sheath covering the braided shield layer,
A braided structure determining step for determining a braided structure of the braided shield layer;
In accordance with the braided structure determined in the braided angle determining step, a braided shield layer forming step of forming a braided shield layer by braiding shield wires;
Including
The braid structure determining step includes
Candidate selection process for selecting braided structure candidates;
About the selected braided structure candidate, a friction amount calculating step for calculating a first friction amount defined as (A) below and / or a second friction amount defined as (B) below;
A determination step of determining the quality of the braided structure by comparing the first friction amount and / or the second friction amount calculated in the friction amount calculation step with a reference value;
Including
In the friction amount calculating step, based on the braided structure parameter that defines the selected braided structure, the computer calculates the braided structure of the shielded wire when the shielded cable is in a straight state, and the shielded cable is in a straight state. Based on the braided structure of the shielded wire and the bending degree of the shielded cable, the computer calculates the braided structure of the shielded wire when the shielded cable is bent, and the shielded wire when the shielded cable is bent Based on the braided structure, the computer calculates the first friction amount and / or the second friction amount,
In the braided shield layer forming step, a braided shield layer having a braided structure suitable for the degree of bending of the shield cable at the time of use is obtained by braiding the shield wire according to the braided structure determined to be good in the determining step. obtain,
The manufacturing method of the shielded cable characterized by the above-mentioned.
(A) The first friction amount indicates a sliding amount in which shield wires intersecting each other slide with each other when the shield cable having the braided shield layer having the braided structure selected in the candidate selecting step is used. Value.
(B) The second friction amount is a sliding amount at which the shield wire slides with respect to the insulating sheath in accordance with repeated bending when using a shielded cable having a braided shield layer having a braided structure selected in the candidate selecting step. A value indicating the amount of movement. A device with a shielded cable with a shielded cable attached to the device body,
The apparatus body includes a bending portion that repeatedly performs a bending operation,
The shielded cable includes a braided shield layer configured so that a plurality of shield wires cross each other and an insulating sheath covering the braided shield layer, and the shielded cable is accompanied by repeated bending operations of the bent portion. , It is attached to the device body so that repeated bending occurs,
Furthermore, the braided shield layer of the shielded cable has a sliding amount of 0.53 mm or less when the shield wire repeatedly slides with respect to the insulating sheath in the bending that is repeatedly caused by the repeated bending operation of the bent portion. With a braided structure ,
The sliding amount is calculated based on a braided structure parameter that defines the braided structure of the braided shield layer, and causes the computer to calculate the braided structure of the shielded wire when the shielded cable is in a straight state, and the shielded cable is in a straight state. Based on the braided structure of the shielded wire and the bending degree of the shielded cable, the computer calculates the braided structure of the shielded wire when the shielded cable is bent, and the shielded wire when the shielded cable is bent An apparatus with a shielded cable, which is calculated by causing a computer to calculate based on a braided structure .

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