JP4283650B2 - Method for designing wire length of electric wire for wire harness and method for determining quality - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a wire harness wire length design method and a quality determination method thereof, and more particularly to a wire harness wire having a higher design accuracy by designing the wire length in consideration of tension. The present invention relates to a long design method and a quality determination method for a wire harness wire to which the wire length design method is applied.

  A so-called wire harness is arranged in a vehicle or indoors, which is configured by bundling a plurality of electric wires and electrically connecting electronic devices, electronic components, and the like. When manufacturing such a wire harness, the wire harness manufacturer usually configures the wire harness based on the wire harness design drawing to which the mounting position of each protective member and the dimensions of each part are attached from a car manufacturer or the like. After determining the cut dimensions of the wires, a connector or the like is attached to these wire ends. And such an electric wire group is wired on a jig | tool board by an operator, and is bound by a tape member etc., and a wire harness is completed. Conventionally, in such a wire harness manufacturing process, the cutting dimension of each electric wire has been designed by, for example, a method called a center line dimension with reference to the dimension information attached to the design drawing.

  However, as shown in FIG. 9, when manufacturing the wire harness W / H using the fork F attached on the jig plate as a guide, the electric wires according to the above designed dimensions are bundled straight, and the connector When the tape member P is wound from the C side, for example, as indicated by W1 in FIG. 9, sagging may occur in any one of the wires in the wire group W constituting the wire harness W / H. Such a sag appears as an extra wire length, and is bent or absorbed as shown by W1 ′ in FIG. 10 (A) or wound as shown by W1 ″ in FIG. 10 (B), When the tape is wound together with other wire groups, the wire harness W / H becomes enlarged or electrically unfavorable.

Therefore, in order to correct such a wire surplus length, the following method has been proposed. For example, there is a method in which an electric wire designed with a center line dimension as described above is actually examined on a jig plate and its extra wire length is corrected (first conventional method). Further, for example, there is a method of correcting the line length in accordance with the fork size and the jig layout based on the diameter of the wire harness (second conventional method). Furthermore, as shown in the following Patent Document 1, there is also a method of performing wire length correction based on the minimum bending radius of the electric wire (third conventional method).
JP 2000-11778

  However, according to the first conventional method, there is a problem that repeated trial manufacture is necessary. Further, according to the second conventional method, since the correction path is largely different from the actual wire path, there is a problem that a prototype for recorrecting the line length is necessary. Furthermore, according to the third conventional method, since tension that is one of the causes of excess length in actual work is not taken into account, excessive tension is likely to occur, and the correction result may be slightly different from the actual one. Conceivable.

  Therefore, in view of the present situation described above, the present invention is designed for a wire harness wire that increases the design accuracy and reduces time waste due to trial creation and trial and error by designing the wire length in consideration of tension. It is an object to provide a line length design method. Moreover, this invention makes it the subject to provide the quality determination method of the suitable electric wire for wire harnesses which applied this wire length design method.

The wire length design method for a wire harness wire according to claim 1, which has been made to solve the above-mentioned problems, is a wire length design method for a wire harness wire. Among the tensile strengths, the one that exhibits the minimum value is the tension reference standard value, and a quarter of this value is the maximum allowable wire tension, which is smaller than the maximum allowable wire tension for both ends of the designed wire. An approximate curve of the designed wire calculated based on the three-point constraint by the arrangement of three forks under tension is used as a correction reference path, and the correction reference path is smaller than the maximum allowable wire tension under the three-point constraint. The radius of curvature of the designed wire bent under tension varies depending on the tension smaller than the maximum allowable wire tension and the relative positional relationship of the three forks. The two extension lines by drawing two extension lines parallel to the fork center line based on the arrangement of the three forks and tangent to the correction reference circle, The maximum tension which is created by a part of the correction reference circle between two points tangent to the two extended lines and is the wire length of the correction reference path under the maximum allowable wire tension with respect to both ends of the designed wire The maximum tension line length calculation step for obtaining the line length, and the extra tension absorption that can be absorbed by winding in a spiral manner in the tape winding process in the manufacturing process of the wire harness is added to the maximum tension line length as an absorbable line length. The maximum extra length line length calculating step for obtaining the maximum extra length line length that is the electric length of the correction reference path, and the electric wire for obtaining the maximum possible length of the electric wire length that is a range between the maximum extra length line length and the maximum tension line length. Longest Can include ranges and calculation steps, and on the basis of the electrical wire length maximum range, to determine the design target line length of the object to be designed wire, characterized in that.

According to the first aspect of the present invention, the approximate curve of the designed wire calculated based on the three-point constraint under an appropriate tension is used as the correction reference path, and the correction is performed under the maximum allowable wire tension for both ends of the designed wire. Electric wire that is in the range between the maximum tension line length that is the wire length of the reference path and the maximum surplus length line length that is the length of the corrected reference path with the extra length absorption added to the maximum tension line length The longest possible range is obtained, and the design target wire length of the designed wire is determined based on the maximum possible wire length range.

  The wire length design method for a wire harness for a wire harness according to claim 2, which has been made to solve the above-mentioned problem, is the wire length design method according to claim 1, wherein an upper limit and a lower limit of an allowable tolerance of the designed wire are set. The tolerance range that is the range of the wire length is compared with the maximum possible wire length range, and the design target wire length of the designed wire is determined so that the tolerance range is within the maximum possible wire length range The method further includes a step.

  According to the second aspect of the present invention, the tolerance range which is the range between the upper limit and the lower limit of the allowable tolerance of the designed wire is compared with the maximum possible cable length range, and the tolerance range is within the maximum possible cable length range. The design target wire length of the to-be-designed electric wire is determined so as to be within the range.

The wire length design method for a wire harness for a wire harness according to claim 3, wherein the wire length design method according to claim 2 is an extra length of the designed wire in the wire length determination step. The design target line length of the to-be-designed electric wire is determined so as to suppress the tension as much as possible and to suppress the tension as much as possible and to keep the tolerance range within the maximum possible range of the electric wire length. .

  According to the third aspect of the present invention, it is possible to suppress the extra length of the designed wire as much as possible, and to suppress the tension on both ends of the designed wire as much as possible, and to keep the tolerance range within the maximum possible range of the wire length. The design target line length of the designed wire is determined.

The wire harness wire quality determination method according to claim 4, which has been made to solve the above-mentioned problems, exhibits a minimum value among the maximum allowable tension, terminal crimping strength, and wire extension strength of the wire harness connector. 3 points due to the arrangement of three forks under tension smaller than the maximum allowable wire tension with respect to both ends of the designed wire, where is the tension reference standard value and ¼ of this value is the maximum allowable wire tension An approximate curve of the designed wire calculated based on the constraint is used as a correction reference path, and the correction reference path is a curve of the designed wire bent by receiving a tension smaller than the maximum allowable wire tension under the three-point constraint. A curvature circle is obtained as a correction reference circle having a radius that varies depending on the tension smaller than the maximum allowable wire tension and the relative positional relationship of the three forks. 2 tangents to the two extension lines and the two extension lines by drawing two extension lines parallel to the fork center line based on the arrangement of the mark and tangent to the correction reference circle A maximum tension line length calculation step for obtaining a maximum tension line length that is a wire length of the correction reference path under a maximum allowable wire tension with respect to both ends of the designed wire , and a portion of the correction reference circle between points; And the maximum tension wire length, the wire length of the correction reference path as an absorbable wire length plus a surplus absorption amount that can be absorbed by spirally winding in the tape winding step in the wire harness manufacturing process. A maximum extra-length line length calculating step for obtaining a maximum extra-length line length; an electric wire length maximum possible range calculating step for obtaining an electric wire length maximum possible range that is a range between the maximum extra-length line length and the maximum tension line length; Public test wire Including a tolerance range which is a range between the upper limit and the lower limit of the above and a maximum possible range of the wire length, and a pass / fail judgment step for judging pass / fail of the wire under test based on the comparison result. And

According to the invention described in claim 4 , the correction under the maximum allowable wire tension with respect to both ends of the wire under test is made the approximate curve of the wire under test calculated based on the three-point constraint under an appropriate tension as the correction reference path. Electric wire that is in the range between the maximum tension line length that is the wire length of the reference path and the maximum surplus length line length that is the length of the corrected reference path with the extra length absorption added to the maximum tension line length The longest possible range is determined, and the quality of the wire under test is determined based on the comparison result between the tolerance range of the wire under test and the maximum possible range of the wire length.

According to the first aspect of the present invention, the approximate curve of the designed wire calculated based on the three-point constraint under an appropriate tension is used as the correction reference path, and the correction is performed under the maximum allowable wire tension for both ends of the designed wire. Electric wire that is in the range between the maximum tension line length that is the wire length of the reference path and the maximum surplus length line length that is the length of the corrected reference path with the extra length absorption added to the maximum tension line length The longest possible range is obtained, and the design target wire length of the designed wire is determined based on the maximum possible wire length range. This makes it possible to design the wire length in consideration of the tension, which has not been made conventionally. That is, excessive tension is not applied to the connector or the like attached to the end portion of the electric wire, and a wire length design is possible in which the extra length is limited to an allowable range. In addition, time waste due to trial production and trial and error as in the conventional method can be reduced. Moreover, the amount of extra wire length that can be absorbed by spirally winding the to-be-designed electric wire, which is assumed in the tape winding step, that is, the above-described maximum possible electric wire length is set. Therefore, the maximum possible range of the wire length is very realistic, and the wire length of the wire harness wire can be designed more realistically.

  According to the second aspect of the present invention, the tolerance range which is the range between the upper limit and the lower limit of the allowable tolerance of the designed wire is compared with the maximum possible cable length range, and the tolerance range is within the maximum possible cable length range. The design target wire length of the to-be-designed electric wire is determined so as to be within the range. As a result, it is possible to design the wire length in consideration of the allowable tolerance of the designed wire.

  According to the third aspect of the present invention, it is possible to suppress the extra length of the designed wire as much as possible, and to suppress the tension on both ends of the designed wire as much as possible, and to keep the tolerance range within the maximum possible range of the wire length. The design target line length of the designed wire is determined. As a result, it is possible to design a wire length that does not apply excessive tension to the connector or the like and also minimizes the amount of extra length. That is, the wire length of the wire harness wire with higher accuracy can be designed.

According to the invention described in claim 4 , the correction under the maximum allowable wire tension with respect to both ends of the wire under test is made the approximate curve of the wire under test calculated based on the three-point constraint under an appropriate tension as the correction reference path. Electric wire that is in the range between the maximum tension line length that is the wire length of the reference path and the maximum surplus length line length that is the length of the corrected reference path with the extra length absorption added to the maximum tension line length The longest possible range is determined, and the quality of the wire under test is determined based on the comparison result between the tolerance range of the wire under test and the maximum possible range of the wire length. As a result, it is possible to determine whether the tolerance range of the wire under test is appropriate using the maximum possible range of the wire length. Therefore, it is possible to accurately determine the quality and practicality of the wire under test.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, in order to understand the present invention more clearly, the following necessary terms are defined. FIG. 1 is a diagram for explaining a three-point constraint curve and the like. FIG. 2 is a diagram for explaining the extra length electric wire length, the extra length absorption amount, and the like.

  Three-point constraint curve: As shown by W1 in FIG. 1, the shape of the electric wire bent under the constraint of arbitrary three locations b1, b2, and b3 is referred to as a three-point constraint curve. In the drawing, a part of the electric wire W1 is restrained by the three-fork F1, but this is not limited to the three-fork F1. In the figure, CL1 and CL2 indicate fork centerlines.

  Wire surplus length: As shown in FIG. 2, the surplus wire length (the length of the surplus wire w2 in the wire harness W / H) and the straight wire length (the length of the straight wire w1 in the wire harness W / H). The difference in wire length is called the extra wire length. The straight wire length matches the wire center length of the wire harness W / H.

  2. Surplus length absorption amount: As shown in FIG. 2, a line between the length of the helical electric wire (the length of the helical electric wire w3 in the wire harness W / H) that can be helically wound in the tape winding process and the linear electric wire length. The length difference is called the extra length absorption.

The maximum allowable wire tension: in the maximum allowable load and terminal crimping strength and wire elongation strength of the connector wire harness, those exhibiting the minimum value as the tension reference standard value, the maximum allowable wire tension quarter of the value That's it.

  Wire length tolerance: The sum of the allowable tolerance upper limits in the wire harness manufacturing process is the wire length allowable tolerance upper limit, and the sum of the allowable tolerance lower limits is the wire length allowable tolerance lower limit. A range between the upper limit of the allowable wire length tolerance and the lower limit of the allowable allowable wire length is referred to as an allowable allowable wire length (see FIG. 6).

  The correction reference path used in the present invention will be described with reference to FIGS. FIG. 3 is a diagram for explaining a correction reference path and the like. FIG. 4 is a diagram for explaining the relationship between the maximum allowable tension path, the minimum allowable tension path, and an appropriate tension path.

  The correction reference path is an approximate curve based on a three-point constraint curve subjected to appropriate tension. The correction reference path is created as follows.

  For example, as indicated by W1 in FIG. 1, the curvature circle of the electric wire bent under appropriate tensions f2 and f3 under the three-point constraint is obtained. Such a curvature circle is referred to as a correction reference circle RC as shown in FIG. The radius r of the correction reference circle RC can vary depending on the magnitudes of the tensions f2 and f3 and the relative positional relationship between the forks F1, F2 and F3, that is, the directions of the tensions f2 and f3.

Next, as shown in FIG. 3, two straight lines P 1-1 parallel to the fork center lines CL1 and CL2 based on the arrangement of the forks F1, F2 and F3 and tangent to the correction reference circle RC are shown. catching P 2 and P 3- P 4. These straight lines are referred to as extension lines P 1 -P 2 and P 3 -P 4. Then, a correction reference path is obtained by combining a part P 2- P 3 of the correction reference circle RC with the extension lines P 1 -P 2 and P 3- P 4.

The appropriate tension is
The relationship of minimum allowable tension <appropriate tension <maximum allowable wire tension must be satisfied. Here, the minimum allowable tension refers to the tension of the path exhibiting the maximum allowable extra length.

In addition, the relationship between the maximum allowable tension path (path corresponding to the maximum allowable wire tension), the minimum allowable tension path (path corresponding to the minimum allowable tension), and the appropriate tension path (path corresponding to the appropriate tension) is The relationship is as shown in FIG.

  Next, an embodiment of a wire length design method for a wire harness wire according to the present invention will be described with reference to FIGS. 5 and 6. FIG. 5 is a flowchart showing an embodiment of a wire length design method for a wire harness wire according to the present invention. FIG. 6 is a diagram showing the relationship among the wire center line length, the maximum extra length line length, the allowable upper limit line length, the design target line length, the allowable lower limit line length, and the maximum tension line length.

In this wire length design method, first, in steps S101, S102, and S103 in FIG. The maximum tension line length corresponds to the length of the maximum allowable tension path shown in FIG. 4, and is the wire length of the correction reference path under the maximum allowable cable tension (Lf in FIG. 6). Further, the maximum extra length line length corresponds to the length of the minimum allowable tension path shown in FIG. 4 and is the wire length of the correction reference path obtained by adding the extra length absorption amount to the maximum tension line length that can be absorbed. Yes (Ls in FIG. 6). The maximum possible wire length range is a range between the maximum extra length line length and the maximum tension line length (in FIG. 6, a range between dlf and dls). Note that step S101, step S102, and step S103 correspond to the maximum tension line length calculation step, the maximum extra length line length calculation step, and the wire length maximum possible range calculation step in claim 1, respectively.

  Next, in step S104 and step S105, allowable tolerance lower limit data and allowable tolerance upper limit data of the designed wire are acquired, and in step S106, a tolerance range is obtained. The allowable tolerance lower limit data and the allowable tolerance upper limit data are data obtained in advance based on the cutting result, the crimping result, the distance between the forks, and the like, and these are acquired in step S104 and step S105.

  The wire length corresponding to the allowable tolerance lower limit is indicated by the allowable tolerance lower limit length L1 in FIG. 6, and the wire length corresponding to the allowable tolerance upper limit is indicated by the allowable tolerance upper limit length Lu in FIG. The tolerance range is a range between the allowable tolerance upper limit and the allowable tolerance lower limit (range a + b between dll and dlu in FIG. 6). In FIG. 6, tensions corresponding to the above-mentioned dlf, dll, dld, dlu, and dls are indicated by Fmax, Fdu, Fd, Fdl, and Fmin, respectively. Lc represents the wire center line length.

  In step S107 and step S108, the tolerance range (the range between dll and dlu in FIG. 6) falls within the maximum possible wire length range (the range between dlf and dls in FIG. 6). (Y of step S107), the design target wire length (Ld of FIG. 6) of the to-be-designed electric wire is determined. Step S107 and step S108 each correspond to the wire length determination step in claim 1.

  According to this embodiment, the design target wire length of the designed wire is determined so that the tolerance range of the designed wire is within the maximum possible length of the wire. This makes it possible to design the wire length in consideration of the tension, which has not been made conventionally. That is, excessive tension is not applied to the connector or the like attached to the end portion of the electric wire, and a wire length design is possible in which the extra length is limited to an allowable range. In addition, time waste due to trial production and trial and error as in the conventional method can be reduced.

  Next, with reference to FIG. 7, another embodiment of the wire length designing method for a wire harness wire according to the present invention will be described. FIG. 7 is a flowchart showing another embodiment of the wire length designing method for a wire harness wire according to the present invention.

  In this wire length design method, first, in step S201, step S202, and step S203 of FIG. 7, as in steps S101, S102, and S103 of the first embodiment, the maximum tension line length and the maximum extra length line of the designed wire. The maximum possible range of length and wire length (range between dlf and dls in FIG. 6) is obtained.

  Next, in step S204 and step S205, as in steps S104 and S105 of the first embodiment, the allowable tolerance lower limit data and the allowable tolerance upper limit data of the designed wire are acquired, and in step S206, the steps of the first embodiment are obtained. Similar to S106, a tolerance range (range between dll and dlu in FIG. 6) is obtained.

  In step S207 to step S209, the tolerance range is within the maximum possible range of the wire length (Y in step S207), and further, the amount of extra wire length is suppressed as much as possible, and the wire tension is suppressed as much as possible. Then, the design target wire length (Ld in FIG. 6) of the designed wire is determined. The second embodiment corresponds to the third aspect.

  According to this embodiment, it is possible to suppress the remaining length of the designed wire as much as possible, and to suppress the tension on both ends of the designed wire as much as possible, and to keep the tolerance range within the maximum possible range of the wire length. The design target line length is determined. As a result, it is possible to design a wire length that does not apply excessive tension to the connector or the like and also minimizes the amount of extra length. That is, the wire length of the wire harness wire with higher accuracy can be designed.

  Furthermore, FIG. 8 is added and the quality determination method of the electric wire for wire harnesses which applied the said wire length design method is demonstrated. FIG. 8 is a flowchart showing an embodiment of a method for determining the quality of a wire harness wire according to the present invention.

In this determination method, first, in step S301, step S302, and step S303 of FIG. 8, the maximum tension line length and the maximum extra length line length of the wire under test are the same as in steps S101, S102, and S103 of the first embodiment. The maximum possible wire length range (range between dlf and dls in FIG. 6) is obtained. Note that step S301, step S302, and step S303 respectively correspond to the maximum tension line length calculation step, the maximum extra length line length calculation step, and the wire length maximum possible range calculation step in claim 4 .

  Next, in step S304 and step S305, as in step S104 and step S105 of the first embodiment, the allowable tolerance lower limit data and the allowable tolerance upper limit data of the wire under test are acquired, and in step S306, the steps of the first embodiment are obtained. Similar to S106, a tolerance range (range between dll and dlu in FIG. 6) is obtained.

In step S307, it is determined whether or not the tolerance range is narrower than the maximum wire length possible range, that is, whether or not the tolerance range is within the maximum wire length possible range. If it is determined that the tolerance range is narrower than the maximum possible wire length range, that is, the tolerance range is within the maximum possible wire length range (Y in step S307), the wire under test may be regarded as a non-defective product. In step S308, it is determined that the electric wire under test is a non-defective product. Otherwise, if it is determined that the tolerance range does not fall within the maximum possible length of the electric wire (N in step S307), the electric wire under test is determined. The electric wire can be regarded as a defective product, and in step S309, the electric wire under test is determined as a defective product. Step S307 corresponds to the quality determination step of claim 4 .

  According to this embodiment, it is possible to determine whether or not the tolerance range of the wire under test is appropriate by applying the wire length design method for the wire harness wire. Therefore, it is possible to accurately determine the quality and practicality of the wire under test.

  As described above, according to the embodiment of the present invention, the wire length design of the electric wires is performed in consideration of the tension, the design accuracy is further improved, and time waste due to trial production and trial and error is reduced. It is possible to provide a wire length design method for electric wires. Further, by applying this wire length design method, it is possible to provide a suitable method for determining the quality of a wire harness wire.

  In the above-described embodiment, the present invention does not limit the design method of an electric wire constrained by three points, but intends the design method of an electric wire constrained by at least three points. Therefore, the present invention can also be applied to the design of electric wires constrained by three or more points.

It is a figure for demonstrating a 3 point | piece constraint curve. It is a figure for demonstrating a surplus length electric wire length, a surplus length absorption amount, etc. FIG. It is a figure for demonstrating a correction | amendment reference | standard path | route. It is a figure for demonstrating the relationship with the maximum allowable tension | tensile_strength path | route, the minimum allowable tension | tensile_strength path | route, and an appropriate tension | tensile_strength path | route. It is a flowchart which shows one Embodiment of the wire length design method of the electric wire for wire harnesses of this invention. It is a figure which shows the relationship between wire center line length, maximum extra length line length, allowable upper limit line length, design target line length, allowable lower limit line length, and maximum tension line length. It is a flowchart which shows other embodiment of the wire length design method of the electric wire for wire harnesses of this invention. It is a flowchart which shows one Embodiment of the quality determination method of the electric wire for wire harnesses of this invention. It is a figure which shows the state which the sagging generate | occur | produced in the electric wire. FIG. 10A and FIG. 10B are diagrams showing a state where tape winding is performed with an electric wire in which sagging has occurred.

Explanation of symbols

W / H Wire harness W, W1 Electric wire C Connector F, F1 Fork CL1, CL2 Fork center line

Claims (4)

In the wire length design method of the wire harness wire,
Among the maximum allowable tension, terminal crimping strength, and wire extension strength of the connector for wire harness, the one that exhibits the minimum value is the tension reference value, and a quarter of this value is the maximum allowable wire tension. Under the tension smaller than the maximum allowable wire tension with respect to both ends of the designed wire, an approximated curve of the designed wire calculated based on the three-point constraint by the arrangement of three forks is used as a correction reference path,
In the correction reference path, a curvature circle of the designed electric wire bent under a tension smaller than the maximum allowable wire tension under the three-point constraint, a relative tension between the tension smaller than the maximum allowable wire tension and the three forks. By calculating two correction lines that are parallel to the fork center line based on the arrangement of the three forks and are tangent to the correction reference circle. The two extension lines and a part of the correction reference circle between two points tangent to the two extension lines,
A maximum tension line length calculating step for obtaining a maximum tension line length that is a wire length of the correction reference path under a maximum allowable wire tension with respect to both ends of the designed wire; and
The maximum excess wire length of the correction reference path, which is the maximum tension wire length plus the absorption length that can be absorbed by winding in a spiral manner in the tape winding process in the manufacturing process of the wire harness. A maximum extra line length calculation step for obtaining a long line length;
A wire length maximum possible range calculation step for obtaining a wire length maximum possible range that is a range between the maximum extra length line length and the maximum tension line length, and
Based on the maximum possible length of the wire length, determine a design target wire length of the designed wire,
A method for designing the length of a wire harness wire. In the wire length design method of the electric wire for wire harnesses according to claim 1,
Compare the tolerance range which is the range between the upper limit and the lower limit of the allowable tolerance of the designed wire, and the maximum possible length of the wire, so that the tolerance range is within the maximum possible length of the wire, Wire length determination step for determining the design target wire length of the designed wire,
A wire length design method for a wire harness wire, further comprising: In the wire length design method of the wire for a wire harness according to claim 2 ,
In the wire length determination step,
The design target wire length of the wire to be designed is determined so as to suppress the remaining amount of the wire to be designed as much as possible and at the same time suppress the tension as much as possible, and the tolerance range is within the maximum possible range of the wire length. To
A method for designing the length of a wire harness wire. In the method for determining the quality of the wire harness wire,
Among the maximum allowable tension, terminal crimping strength, and wire extension strength of the connector for wire harness, the one that exhibits the minimum value is the tension reference value, and a quarter of this value is the maximum allowable wire tension. The approximate curve of the designed wire calculated based on the three-point constraint by the arrangement of the three forks under a tension smaller than the maximum allowable wire tension with respect to both ends of the designed wire is a correction reference path,
The correction reference path includes a curvature circle of the designed wire bent under a tension smaller than the maximum allowable wire tension under the three-point constraint, and a relative tension between the tension smaller than the maximum allowable wire tension and the three forks. By calculating two correction lines that are parallel to the fork center line based on the arrangement of the three forks and are tangent to the correction reference circle. The two extension lines and a part of the correction reference circle between two points tangent to the two extension lines,
A maximum tension line length calculating step for obtaining a maximum tension line length that is a wire length of the correction reference path under a maximum allowable wire tension with respect to both ends of the designed wire; and
The maximum excess wire length of the correction reference path, which is the maximum tension wire length plus the absorption length that can be absorbed by winding in a spiral manner in the tape winding process in the manufacturing process of the wire harness. A maximum extra line length calculation step for obtaining a long line length;
Wire length maximum possible range calculation step for obtaining the maximum possible wire length range that is the range between the maximum extra length wire length and the maximum tension wire length;
A pass / fail judgment step that compares a tolerance range that is a range between an upper limit and a lower limit of the tolerance of the wire under test, and the maximum possible range of the wire length, and judges pass / fail of the wire under test based on the comparison result; ,
The quality determination method of the electric wire for wire harnesses characterized by including.

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