JP5128352B2 - Electrical connection box mounting structure design system, mounting structure design method, program and mounting structure - Google Patents

Description

  The present invention relates to an attachment structure design system for an electrical junction box, an attachment structure design method, a program, and an attachment structure. In particular, the wire harness composite with the attachment position or attachment angle of the wire harness drawer part that suppresses the resonance of the electric connection box to the external vibration most greatly, or the rigidity value of the wire harness is changed based on the electric connection box attachment restriction conditions By searching or selecting the structure of the body and attaching the wire harness complex to the electrical junction box based on the obtained conditions, it is possible to prevent breakage of parts such as brackets and relays due to resonance of the electrical junction box The present invention relates to a mounting structure design system, a mounting structure design method, a program, and a mounting structure for an electrical junction box.

  The electrical junction box, which is a structure having a housing with built-in electronic components, needs to protect the built-in electronic components, and the harsh usage conditions for the electrical junction box and the bracket itself that fixes it to the outside. It is necessary to maintain durability over a long period of time. For example, in an automobile, a design that ensures fatigue durability such as an electrical junction box housing or a bracket against vibrations generated when the engine is started or when running is required.

In addition, the wire harness that bundles the electronic components built in the electrical junction box and the wires that connect the outside is proposed to prevent abnormal vibration of the wire harness itself and to prevent abnormal noise and damage based on the vibration. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 9-37437

  As a conventional problem, when the electrical junction box resonates within the frequency range of vibrations that the automobile receives during actual driving, for example, the bracket fixed to the vehicle body is damaged or the mounted parts are damaged. There was a problem that it was. Further, in the design trial production stage, if the durability test is not passed, the design trial production must be performed again. For this reason, there has been a problem that the design takes time and cost.

  In addition, after mass production and sales, the electrical junction box resonated unexpectedly, and parts such as brackets and relays were destroyed, which had to be dealt with.

  The present invention has been made to solve the above problems, and based on the electrical connection box mounting constraint conditions, the mounting position of the wire harness drawer portion that most suppresses the resonance of the electrical connection box with respect to external vibrations. Or, by searching or selecting the mounting angle or the configuration of the wire harness complex and attaching the wire harness complex to the electrical junction box based on the obtained conditions, the bracket, relay, etc. due to the resonance of the electrical junction box It is an object of the present invention to provide an electrical connection box mounting structure design system, a mounting structure design method, a program, and a mounting structure capable of preventing the destruction of parts.

The following invention is provided to solve the above-mentioned conventional problems.
The electrical connection box mounting structure design system according to the first aspect of the present invention includes a fixing portion that fixes at least one place to an external housing, a wire harness extraction portion from which a wire harness composed of a plurality of electric wire bundles is drawn, and An electrical connection box mounting structure design system for mounting an electrical connection box having the above in the external casing,
When the wire harness is attached to the electrical junction box, it is within a predetermined position range on the electrical junction box based on an installation restriction condition for attaching the electrical junction box in the external housing, and is free from external vibration. An attachment position search means for searching for an attachment position of the wire harness take-out portion that most suppresses resonance of the electrical junction box;
When the wire harness is attached to the electrical junction box, the wire harness is taken out to suppress the resonance of the electrical junction box with respect to external vibration most at a predetermined attachment position on the electrical junction box based on the attachment constraint condition. A mounting angle searching means for searching for a mounting angle of the part;
When the wire harness is attached to the electrical junction box, based on the attachment constraint condition, the wire harness composite having undergone a stiffness value change of the wire harness that most suppresses resonance of the electrical junction box with respect to external vibration. A wire harness complex selecting means for selecting a configuration;
Selection / execution means for selecting and executing at least one of the attachment position search means, the attachment angle search means, and the wire harness complex selection means based on the attachment constraint condition;
With
The attachment position search means includes
A reference frequency analysis means for calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in a state where there is no wire harness ;
When the wire harness is attached to various positions Pi within a predetermined position range on the electrical junction box, the resonance frequency f (i) that the composite system composed of the electrical junction box and the wire harness exhibits against external vibration. Frequency analysis means for calculating
Various positions Pm as the largest difference value among the results of calculating the difference Delta] f (i) between the resonance frequency f ₀ which is calculated from the reference frequency analysis means and the resonance frequency f (i) calculated from the frequency analysis means An attachment position determining means for extracting the position Pm or the vicinity of the position Pm as the attachment position of the wire harness take-out portion;
With
Search result or selection result by at least one of the attachment position search means, the attachment angle search means, and the wire harness complex selection means selected and executed by the selection / execution means, and Based on the attachment constraint condition, the attachment position or attachment angle of the wire harness take-out portion or the configuration of the wire harness complex is determined.

  By attaching the wire harness composite to the electrical junction box based on the determined installation position or angle of the wire harness take-out portion or the configuration of the wire harness complex, the resonance of the electrical junction box against external vibration can be suppressed. it can.

  Here, suppressing the resonance of the electrical junction box with respect to external vibration means moving the resonant frequency of the electrical junction box to the high frequency side, or reducing the displacement (or amplitude) generated by the resonance of the electrical junction box. It is. In addition, the reference wire harness is reinforced, that is, the rigidity value is increased (for example, the harness tape is wound, the cross-sectional area of the wire harness is increased, the support wire for supporting the wire harness is provided) The wire harness in a state where the reinforcement is applied is called a wire harness complex, and the configuration of the applied reinforcement is called the configuration of the wire harness complex. However, the configuration when no reinforcement is applied is also one of the configurations of the wire harness complex.

  Therefore, the wire harness complex is attached to the electrical junction box, and the resonance frequency of the electrical junction box is moved to the high frequency side, or the displacement (or amplitude) generated by the resonance is reduced, thereby being fixed to the vehicle body. The load on the bracket can be reduced and the life of the electrical junction box can be extended. Since the displacement caused by resonance has a certain relationship with the resonance acceleration, it is also effective to reduce the resonance acceleration.

  As a method for reducing the displacement (or amplitude) caused by resonance, it is effective to increase the attenuation as much as possible. Determining the attachment position, angle, arrangement, etc. of the wire harness that increases the attenuation is an important part of the present invention, and is effective at the same time or independently of moving the resonance frequency.

  Further, when designing the electrical junction box, the wire harness can be considered as a part of the structure, thereby widening the design range and shortening the design time. In addition, even if the electrical connection box resonates more than expected after installation on the actual vehicle, causing damage to the bracket, etc., or failure, the wire junction can be changed without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing and changing the fixed position.

In the above-described invention, the position where the resonance frequency of the composite system composed of the electrical connection box and the wire harness composite with respect to external vibration is moved to the highest frequency side with the wire harness attached to the electrical connection box is searched and By determining and attaching a wire harness at the determined position, resonance of the electrical junction box is suppressed.

  This determines the mounting position of the wire harness take-out part that moves the resonance frequency of the composite system consisting of the electrical connection box and the wire harness complex against external vibration to the highest frequency side based on the mounting constraints of the electrical connection box. can do. Therefore, by attaching the wire harness to the electrical junction box and moving the resonance frequency of the composite system composed of the electrical junction box and the wire harness complex to the high frequency side, the load on the bracket fixed to the vehicle body is reduced. Can extend the life of the electrical junction box.

The electrical connection box mounting structure design system according to the second aspect of the present invention is such that the mounting position search means of the electrical connection box mounting structure design system according to the first aspect of the present invention is provided on the electrical connection box. When the wire harness is attached to various positions Pi within a predetermined position range, the displacement u (i) generated by the composite system composed of the electrical junction box and the wire harness with respect to the external vibration at the resonance frequency f is calculated. And a position Pm having the smallest displacement value among the results of the displacement u (i) calculated by the displacement analyzing means is extracted from the various positions Pi, and the extracted position Pm or the And an attachment position determining means for determining the vicinity of the position Pm as an attachment position of the wire harness take-out portion.

  The above-mentioned invention suppresses resonance of the electrical junction box by searching and determining a position where the displacement due to resonance of the electrical junction box with respect to external vibration is the smallest in the absence of the wire harness and attaching the wire harness to the decided position. To do.

  Thereby, the attachment position of the wire harness take-out portion that minimizes the displacement caused by the resonance of the electric connection box with respect to external vibration can be searched and determined based on the attachment restriction condition of the electric connection box. Therefore, by attaching the wire harness to the electrical junction box and reducing the displacement caused by resonance of the electrical junction box, it is possible to reduce the load on the bracket fixed to the vehicle body and extend the life of the electrical junction box. it can.

The electrical connection box mounting structure design system according to the third aspect of the present invention is such that the mounting angle search means of the electrical connection box mounting structure design system according to the first aspect of the present invention has no wire harness. A reference frequency analyzing means for calculating a resonance frequency f ₀ with respect to external vibration of the electrical connection box, and the electrical connection when the wire harness is mounted at a predetermined position P on the electrical connection box at various angles θi. From the frequency analysis means for calculating the resonance frequency f (i) that the composite system composed of the box and the wire harness shows against external vibration, the resonance frequency f (i) calculated from the frequency analysis means, and the reference frequency analysis means The angle θm, which is the largest difference value among the results of calculating the difference Δf (i) from the calculated resonance frequency f _0, is set to various angles θi. And an attachment angle determining means for extracting from the inside and determining the extracted angle θm or the vicinity of the angle θm as an attachment angle of the wire harness take-out portion.

  The above-mentioned invention searches and determines an angle that moves the resonance frequency of the composite system composed of the electrical connection box and the wire harness to the external vibration to the highest frequency side with the wire harness attached to the electrical connection box, and determines By attaching the wire harness to the angle, the resonance of the electrical junction box is suppressed.

  This determines the mounting angle of the wire harness take-out part that moves the resonance frequency of the composite system composed of the electrical connection box and the wire harness to the external vibration to the highest frequency side based on the mounting constraints of the electrical connection box. Can do. Therefore, by attaching the wire harness to the electrical junction box and moving the resonance frequency of the composite system composed of the electrical junction box and the wire harness to the high frequency side, the load on the bracket fixed to the vehicle body is reduced and the electrical The life of the junction box can be extended.

The electrical connection box mounting structure design system according to the fourth aspect of the present invention is such that the mounting angle search means of the electrical connection box mounting structure design system according to the first aspect of the present invention is provided on the electrical connection box. When the wire harness is attached to the predetermined position P at various angles θi, the displacement u occurs in the electrical connection box with respect to external vibration at the resonance frequency f of the composite system composed of the electrical connection box and the wire harness. The displacement analysis means for calculating (i) and the angle θm that is the smallest displacement value among the results of the displacement u (i) calculated by the displacement analysis means are extracted from the various angles θi and extracted. Mounting angle determining means for determining the angle θm or the vicinity of the angle θm as a mounting angle of the wire harness take-out portion. .

  In the above-described invention, with the wire harness attached, the electrical connection box is searched for and determined the angle at which the displacement caused by resonance of the electrical connection box is minimized with respect to external vibration, and the wire harness is attached to the determined angle to establish the electrical connection. Suppresses the resonance of the box.

  Accordingly, it is possible to search and determine the attachment angle of the wire harness take-out portion that minimizes the displacement caused by the resonance of the electric connection box with respect to external vibration based on the attachment restriction condition of the electric connection box. Therefore, by attaching the wire harness to the electrical junction box and reducing the displacement caused by resonance of the electrical junction box, it is possible to reduce the load on the bracket fixed to the vehicle body and extend the life of the electrical junction box. it can.

The electrical junction box mounting structure design system according to the fifth aspect of the present invention is the electrical harness box selecting structure of the electrical junction box mounting structure design system according to the first aspect of the present invention. And the effective stiffness value G of the composite system composed of the wire harness composite and the resonance frequency f of the composite system, and further, the wire harness composite corresponding to the target resonance frequency f _d of the composite system and stiffness value calculating means for calculating a stiffness value G _d of the body, the configuration of the stiffness value calculated stiffness value greater than the stiffness value G _d of the wire harness complex calculated by means obtained the wire harness complex, wherein And a configuration condition selecting means for selecting based on the mounting constraint condition.

  Thereby, the rigidity value of the wire harness composite which becomes more than the target resonance frequency can be selected. Therefore, when designing the electrical junction box, the wire harness can be considered as a part of the structure, so that the design range can be expanded and the design time can be shortened. In addition, even if the electrical connection box resonates more than expected after installation on the actual vehicle, causing damage to the bracket, etc., or failure, the wire junction can be changed without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing and changing the fixed position.

The electrical connection box mounting structure design system according to the sixth aspect of the present invention is the electrical connection box mounting structure design system according to the fifth aspect of the present invention, wherein the configuration of the wire harness complex is the wire harness. And a support line made of a rigid body that is provided along the wire harness and is bound or combined with the wire harness in at least two places, and the configuration condition selecting means is calculated by the rigidity value calculating means wherein the stiffness values described above stiffness value G _d of the wire harness complex is obtained which is, and adjusting dimensions and materials of the support wire, as well as binding portion or the number of the number of binding points.

  Thereby, when designing an electrical junction box, the wire harness can be considered as a part of the structure, so that the design range can be expanded and the design time can be shortened. In addition, even if the electrical connection box resonates more than expected after installation on the actual vehicle, causing damage to the bracket, etc., or failure, the wire junction can be changed without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing and changing the fixed position.

The electrical connection box mounting structure design system according to the seventh aspect of the present invention is the electrical connection box mounting structure design system according to the fifth aspect of the present invention, wherein the configuration of the wire harness complex is the wire harness. And a harness tape wound around the wire harness, and the configuration condition selecting means adjusts the winding method of the harness tape with respect to the wire harness based on the distance between the tapes of the harness tape and the tape width. It is characterized by.

  Thereby, when designing an electrical junction box, the wire harness can be considered as a part of the structure, so that the design range can be expanded and the design time can be shortened. In addition, even if the electrical connection box resonates more than expected after installation on the actual vehicle, causing damage to the bracket, etc., or failure, the wire junction can be changed without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing and changing the fixed position.

The electrical connection box mounting structure design system according to the eighth aspect of the present invention is the rigidity value calculation means of the electrical connection box mounting structure design system according to any one of the fifth to seventh aspects of the present invention. When the resonance frequency of the composite system is f, the effective stiffness value of the composite system is G, the effective density of the composite system is ρ, and the constant term is C,
As basic equations, the the effective rigidity G of the composite system based on the correlation between the rigidity G ₀ of the wire harness complex, calculating the stiffness value G _d of the wire harness complexes targeted It is characterized by.

  Thereby, the rigidity value of the wire harness which becomes more than the target resonance frequency can be searched. Therefore, when designing the electrical junction box, the wire harness can be considered as a part of the structure, so that the design range can be expanded and the design time can be shortened.

In the electrical connection box mounting structure design method according to the first aspect of the present invention, a computer is used to pull out a fixed portion that fixes at least one place to an external housing and a wire harness composed of a plurality of wire bundles. An electrical connection box having a wire harness take-out portion, and an electrical connection box mounting structure design method for mounting in the external housing,
The computer is
(A1) Based on the mounting constraint condition of the electrical connection box for mounting in the external casing acquired from the mounting condition storage unit , (b1) the mounting constraint when the wire harness is mounted on the electrical connection box Searching for the attachment position of the wire harness take-out portion that most suppresses resonance of the electrical junction box with respect to external vibrations within a predetermined range of positions on the electrical junction box based on conditions; and (b2) the wire When the harness is attached to the electrical junction box, the wire harness take-out portion that most suppresses the resonance of the electrical junction box with respect to external vibration at a predetermined attachment position on the electrical junction box based on the attachment constraint condition. Searching for the mounting angle; and (b3) taking the wire harness into the electrical junction box. From the step of selecting the configuration of the wire harness composite that has undergone the rigidity value change of the wire harness that most suppresses the resonance of the electrical junction box with respect to external vibration based on the mounting constraint condition. Selecting at least one process;
(A2) Execution order in which all processes selected by the step (a1) among the process (b1), the process (b2), and the process (b3) are determined based on the attachment constraint condition Steps to be performed according to
(A3) determining the attachment position or attachment angle of the wire harness take-out portion, or the configuration of the wire harness complex, based on the result executed in step (a2) and the attachment constraint condition;
Equipped with a,
The step (b1)
(C1) calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in the absence of the wire harness ;
(C2) Resonance frequency exhibited by the composite system composed of the electrical connection box and the wire harness with respect to external vibration when the wire harness is attached to various positions Pi within a predetermined position range on the electrical connection box calculating f (i);
(C3) the largest difference value among the step (c2) calculated resonance frequency f (i) and the step (c1) the difference Delta] f (i) was calculated result of the resonance frequency f ₀ which is calculated from from Extracting the position Pm from the various positions Pi, and determining the extracted position Pm or the vicinity of the position Pm as an attachment position of the wire harness extraction portion;
Characterized in that it comprises a.

  Thereby, the effect equivalent to the attachment structure design system of the electrical junction box concerning the 1st mode of the present invention mentioned above is acquired.

In the electrical connection box mounting structure design method according to the second aspect of the present invention, the step (b1) of the electrical connection box mounting structure design method according to the first aspect of the present invention comprises (d1) the electrical connection. Displacement u () caused by external vibration at a resonance frequency f of a composite system composed of the electrical connection box and the wire harness when the wire harness is attached to various positions Pi within a predetermined position range on the box. a step of calculating i), and (d2) extracting the position Pm having the smallest displacement value among the results of the displacement u (i) calculated in the step (d1) from the various positions Pi And a step of determining the position Pm or the vicinity of the position Pm as an attachment position of the wire harness take-out portion.

Thereby, the effect equivalent to the attachment structure design system of the electrical junction box concerning the 2nd aspect of the present invention mentioned above is acquired.

In the electrical connection box mounting structure design method according to the third aspect of the present invention, the step (b2) of the electrical connection box mounting structure design method according to the first aspect of the present invention includes (e1) the wire harness. A step of calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in the absence of the electrical connection box, and (e2) when the wire harness is mounted at various angles θi at a predetermined position P on the electrical junction box, A step of calculating a resonance frequency f (i) exhibited by the composite system including the electrical junction box and the wire harness with respect to external vibration; (e3) the resonance frequency f (i) calculated from the step (e2); The angle θm that is the largest difference value among the results of calculating the difference Δf (i) from the resonance frequency f ₀ calculated in the step (e1) is extracted from the various angles θi before the extraction. And a step of determining the angle θm or the vicinity of the angle θm as an attachment angle of the wire harness take-out portion.

Thereby, the effect equivalent to the attachment structure design system of the electrical junction box concerning the 3rd aspect of the present invention mentioned above is acquired.

The electrical connection box mounting structure design method according to the fourth aspect of the present invention includes the step (b2) of the electrical connection box mounting structure design method according to the first aspect of the present invention, wherein (f1) the electrical connection is performed. When the wire harness is mounted at a predetermined position P on the box at various angles θi, the electrical connection box is resistant to external vibration at a resonance frequency f of a composite system composed of the electrical connection box and the wire harness. A step of calculating the generated displacement u (i); and (f2) an angle θm that is the smallest displacement value among the results of the displacement u (i) calculated in the step (f1) is selected from the various angles θi. And extracting and extracting the extracted angle θm or a vicinity of the angle θm as an attachment angle of the wire harness take-out portion.

Thereby, the effect equivalent to the attachment structure design system of the electrical junction box concerning the 4th aspect of the present invention mentioned above is acquired.

In the electrical connection box mounting structure design method according to the fifth aspect of the present invention, the step (b3) of the electrical connection box mounting structure design method according to the first aspect of the present invention comprises (g1) the electrical connection. obtained relation between the effective rigidity G and the resonance frequency f of the composite systems of the composite system consisting of a box and the wire harness complexes further the wire harness corresponding to the resonance frequency f _d of a target of the composite system calculating a stiffness value G _d of the complex, the structure of the wire harness composite stiffness value greater than the stiffness value G _d of the wire harness complex calculated is obtained by (g2) said step (g1), And a step of selecting based on the mounting constraint condition.

Thereby, an effect equivalent to the electrical connection box mounting structure design system according to the fifth aspect of the present invention described above can be obtained.

The electrical connection box mounting structure design method according to the sixth aspect of the present invention is the electrical connection box mounting structure design method according to the fifth aspect of the present invention, wherein the configuration of the wire harness complex is the wire harness. And a support line made of a rigid body that is provided along the wire harness and is bound or combined with the wire harness at at least two locations, and the step (g2) is calculated by the step (g1). wherein the stiffness values described above stiffness value G _d of the wire harness complex is obtained which is, and adjusting dimensions and materials of the support wire, as well as binding portion or the number of the number of binding points.

Thereby, the effect equivalent to the attachment structure design system of the electrical junction box concerning the 6th aspect of the present invention mentioned above is acquired.

The electrical connection box mounting structure design method according to the seventh aspect of the present invention is the electrical connection box mounting structure design method according to the fifth aspect of the present invention, wherein the configuration of the wire harness complex is the wire harness. And a harness tape wound around the wire harness, and the step (g2) adjusts the winding method of the harness tape around the wire harness based on the distance between the tapes of the harness tape and the tape width. It is characterized by.

Thereby, an effect equivalent to the electrical connection box mounting structure design system according to the seventh aspect of the present invention described above can be obtained.

The electrical connection box mounting structure design method according to the eighth aspect of the present invention includes the step (g1) of the electrical connection box mounting structure design method according to any one of the fifth to seventh aspects of the present invention. When the resonance frequency of the composite system is f, the effective stiffness value of the composite system is G, the effective density of the composite system is ρ, and the constant term is C,
As basic equations, the the effective rigidity G of the composite system based on the correlation between the rigidity G ₀ of the wire harness complex, calculating the stiffness value G _d of the wire harness complexes targeted It is characterized by.

Thereby, the same effect as the electrical connection box mounting structure design system according to the eighth aspect of the present invention described above can be obtained.

The program according to the first aspect of the present invention includes an electrical connection box having a fixed portion that fixes at least one place to an external housing, and a wire harness extraction portion from which a wire harness composed of a plurality of wire bundles is drawn. A program for causing a computer to execute an assembly design process of an electrical connection box for mounting in the external casing, and mounting the electrical connection box according to any one of the first to eighth aspects of the present invention described above The computer is caused to execute processing for realizing each means of the structural design system.

If it is such a structure, when a computer reads a program and a computer performs a process with the read program, attachment of the electrical junction box concerning any one aspect of 1 to 8 of the present invention mentioned above The same effect as the structural design system can be obtained.

The mounting structure of the electrical junction box according to the first aspect of the present invention includes a fixed portion that fixes at least one place to the external housing, and a wire harness extraction portion from which a wire harness composed of a plurality of wire bundles is drawn. An electrical junction box mounting structure for mounting an electrical junction box in the external casing, which is determined by the electrical junction box mounting structure design system according to any one of the first to eighth aspects of the present invention described above. The said wire harness was attached based on the attachment position or attachment angle of the said wire harness taking-out part made, or the structure of a wire harness complex.

Thereby, an effect equivalent to the mounting structure design system for an electrical junction box according to any one of the first to eighth aspects of the present invention described above can be obtained.

  According to the present invention, by attaching the wire harness complex to the electrical junction box based on the determined attachment position or angle of the wire harness take-out portion or the configuration of the wire harness complex, Resonance can be suppressed.

  Therefore, by attaching the wire harness complex to the electric junction box and moving the resonance frequency of the electric junction box to the high frequency side, or by reducing the displacement or resonance acceleration due to resonance, the bracket fixed to the vehicle body In addition, the life of the electrical junction box can be extended.

  Further, when designing the electrical junction box, the wire harness can be considered as a part of the structure, thereby widening the design range and shortening the design time. In addition, even if the electrical connection box resonates more than expected after installation on the actual vehicle, causing damage to the bracket, etc., or failure, the wire junction can be changed without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing and changing the fixed position.

  An embodiment of the present invention will be described with reference to the drawings. In addition, embodiment described below is for description and does not limit the scope of the present invention. Accordingly, those skilled in the art can employ embodiments in which each or all of these elements are replaced by equivalents thereof, and these embodiments are also included in the scope of the present invention.

  FIG. 1 is a diagram illustrating an example of a system configuration of an electrical junction box mounting structure design system 10 to which the present invention can be applied. FIG. 2 is a diagram illustrating an example of a detailed system configuration of the attachment position search unit 11 of the attachment structure design system 10. FIG. 3 is a diagram illustrating an example of a detailed system configuration of the attachment angle search unit 12 of the attachment structure design system 10. FIG. 4 is a diagram illustrating an example of a detailed system configuration of the wire harness complex selecting unit 13 in the mounting structure design system 10.

  FIG. 5 is a diagram for explaining an electrical junction box to which the present invention is applicable. FIG. 5A is an external perspective view of the electrical junction box to which the wire harness is attached, and FIG. 5B is a diagram for explaining the attachment position of the wire harness take-out portion. () Is a figure for demonstrating the attachment angle of a wire harness taking-out part, and FIG.5 (d) is a figure for demonstrating the structure of a wire harness composite_body | complex.

  FIG. 6 is a view for explaining how to wind the harness tape wound around the wire harness. FIG. 6A is a diagram illustrating a state where the harness tape is not overlapped at the distance d between the tapes, and FIG. 6B is a diagram illustrating a state where the harness tape is overlapped.

  As shown in FIG. 5 (a), an electrical connection box 50 includes a housing 53 containing electronic components, a fixed portion (bracket) 51 fixed to an external housing (not shown), and a plurality of wire bundles. And a wire harness take-out portion 52 from which the wire harness 61 is pulled out.

  The electrical connection box 50 mounting structure design system 10 to which the present invention can be applied shown in FIG. 1 is designed to take out an optimal wire harness under the mounting constraints in order to reduce resonance of the electrical connection box 50 with respect to external vibration. This is a system for searching or selecting the mounting position or mounting angle of the portion 52 or the configuration of the wire harness complex.

  As shown in FIG. 1, the attachment structure design system 10 includes an attachment position search unit 11, an attachment angle search unit 12, a wire harness complex selection unit 13, a selection / execution unit 14, and an attachment constraint condition storage unit 15. Yes.

  First, the attachment position search part 11 is demonstrated with reference to FIG.1, FIG.2 and FIG.5 (b). The attachment position search part 11 is concrete in the position range 53a on the electrical connection box 50 to which the wire harness 61 stored in the attachment restriction condition storage part 15 as shown in FIG. The position Pm that most suppresses the resonance with respect to the external vibration of the electrical connection box 50 is extracted as the attachment position P of the wire harness take-out portion 52 among the n positions Pi (1 ≦ i ≦ n) of the position range 53a. To do.

  Here, the position Pm that most suppresses the resonance with respect to the external vibration of the electrical connection box 50 means that when the wire harness 61 is attached to the electrical connection box 50, the resonance frequency with respect to the external vibration of the electrical connection box 50 is the highest frequency side. Or the vicinity thereof, or the position where the displacement or resonance acceleration with respect to the external vibration of the electrical connection box 50 is minimized or the vicinity thereof.

  It should be noted that there is a certain relationship between the displacement of the electrical junction box caused by resonance and the resonance acceleration, and if one is obtained, the other can be obtained. Therefore, in this specification, it describes about the case where a displacement is calculated | required. Note that amplitude may be obtained instead of displacement or resonance acceleration.

  In addition, the position range 53a on the electrical connection box 51 to which the wire harness 61 can be attached is a space in which the electrical connection box 50, the shape and arrangement of components mounted on the electrical connection box 50, and the like, and the electrical connection box are mounted. It is determined in advance according to conditions (for example, an engine room of a car).

  As shown in FIG. 2, the attachment position search unit 11 includes a frequency factor position search unit 21 and a displacement factor position search unit 22. The frequency factor position search unit 21 attaches the wire harness 61 to extract and determine the position where the resonance frequency with respect to external vibration of the composite system including the electrical connection box 50 and the wire harness 61 is on the highest frequency side or the vicinity thereof. Further, the displacement factor position search unit 22 extracts and determines a position where the displacement caused by the external vibration in the electrical connection box 50 is the smallest in the state where the wire harness 61 is attached or the vicinity thereof.

  In addition, the frequency factor position search unit 21 or the displacement factor is not determined by both the frequency factor position search unit 21 and the displacement factor position search unit 22 but by the selection / execution unit 14 described later. Either one of the position search parts 22 is selected, and the attachment position of the wire harness extraction part 52 is determined by the selected search part. As a tendency, the attachment position determined by the frequency factor position search unit 21 has a greater effect of suppressing resonance with respect to external vibration of the electrical connection box 50 than the attachment position determined by the displacement factor position search unit 22.

The frequency factor position search unit 21 described above includes a reference frequency analysis unit 23, a frequency analysis unit 24, and an attachment position determination unit 25, as shown in FIG. The reference frequency analysis unit 23 calculates a resonance frequency f ₀ with respect to external vibration of the electrical connection box 50 in a state where the wire harness 61 is not attached. Further, the frequency analysis unit 24 is configured to externally vibrate the composite system composed of the electrical connection box 50 and the wire harness 61 when the wire harness 61 is attached to various positions Pi within a predetermined position range 53 a on the electrical connection box 50. The resonance frequency f (i) is calculated.

In addition, the attachment position determination unit 25 calculates the difference Δf (i) between the resonance frequency f (i) calculated by the frequency analysis unit 24 and the resonance frequency f ₀ calculated by the reference frequency analysis unit 23 on the electrical connection box 50. Calculate for all positions Pi within a predetermined position range, extract the largest difference Δf (m) from the calculated results and the position Pm at that time, and optimize the position Pm or the vicinity of the position Pm It is set as the attachment position P of the said wire harness taking-out part 52.

  The displacement factor position search unit 22 described above includes a displacement analysis unit 26 and an attachment position determination unit 27, as shown in FIG. When the wire harness 61 is attached to various positions Pi within a predetermined position range 53a on the electrical connection box 50, the displacement analysis unit 26 detects that the composite system including the electrical connection box 50 and the wire harness 61 is resistant to external vibration. The resulting variable u (i) is calculated.

  The attachment position determination unit 27 extracts the smallest displacement u (m) and the position Pm at that time from the result of the variable u (i) calculated by the displacement analysis unit 26, and the position Pm or the vicinity of the position Pm Is the optimum mounting position P of the wire harness take-out portion 52.

  Next, the attachment angle search part 12 is demonstrated with reference to FIG.1, FIG3 and FIG.5 (c). As illustrated in FIG. 5C, the attachment angle search unit 12 has n angles θi (1) at a position P on the electrical connection box 50 to which the wire harness 61 stored in the attachment constraint condition storage unit 15 is attached. ≦ i ≦ n), the angle θm that most suppresses the resonance with respect to the external vibration of the electrical junction box 50 is extracted and determined as the attachment angle θ of the wire harness takeout portion 52.

  In addition, in FIG.5 (c), since it has shown about the case where the attachment angle of the wire harness taking-out part 52 is searched in xz plane, it represents with one variable (theta) i (an angle from the reference line 59). However, depending on the conditions of the surrounding environment to which the electrical junction box 50 is attached, it may be preferable to search the attachment angle of the wire harness take-out portion 52 in the xyz space. In such a case, the angle is expressed by two variables.

  As shown in FIG. 3, the attachment angle search unit 12 includes a frequency factor angle search unit 31 and a displacement factor angle search unit 32. The frequency factor angle search unit 31 attaches the wire harness 61 to extract and determine the angle at which the resonance frequency with respect to external vibration of the electrical connection box 50 is on the highest frequency side or the vicinity thereof. Further, the displacement factor angle search unit 32 extracts and determines an angle at which the displacement generated in the electrical connection box 50 with respect to external vibration becomes the smallest or the vicinity thereof with the wire harness 61 attached.

  The frequency factor angle search unit 31 or the displacement factor is not determined by both the frequency factor angle search unit 31 and the displacement factor angle search unit 32, but by the selection / execution unit 14 described later. Either one of the angle search parts 32 is selected, and the attachment angle of the wire harness take-out part 52 is determined by the selected search part.

The frequency factor angle search unit 31 described above includes a reference frequency analysis unit 33, a frequency analysis unit 34, and an attachment angle determination unit 35, as shown in FIG. The reference frequency analysis unit 33 calculates a resonance frequency f ₀ with respect to external vibration of the electrical connection box 50 in a state where the wire harness 61 is not attached. Further, the frequency analysis unit 34 calculates a resonance frequency f (i) with respect to external vibration of the electrical connection box 50 when the wire harness is attached to the attachment position P at various angles θi.

Further, the attachment angle determination unit 35 sets the difference Δf (i) between the resonance frequency f (i) calculated by the frequency analysis unit 34 and the resonance frequency f ₀ calculated by the reference frequency analysis unit 33 for all angles θi. The largest difference Δf (m) and the angle θm at that time are extracted from the calculated results, and the angle θm or the vicinity of the angle θm is the optimum mounting angle θ of the wire harness take-out portion 52. To do.

  The displacement factor angle search part 32 mentioned above is provided with the displacement analysis part 36 and the attachment angle determination part 37, as shown in FIG. The displacement analysis unit 36 calculates the displacement u (i) with respect to the external vibration of the electrical connection box 50 when the wire harness 61 is attached to the attachment position P at various angles θi.

  The attachment angle determination unit 37 extracts the smallest displacement u (m) and the angle θm at that time from the result of the displacement u (i) calculated by the displacement analysis unit 36, and the angle θm or the vicinity of the angle θm Is the optimum mounting angle θ of the wire harness take-out portion 52.

  Next, the wire harness complex selecting unit 13 will be described with reference to FIGS. 1, 4, 5 (d) and 6. The wire harness complex selecting unit 13 targets the complex system composed of the electrical connection box 50 and the wire harness complex 60 based on the mounting constraint condition of the electrical connection box 50 stored in the mounting constraint condition storage unit 15. The configuration of the wire harness composite 60 having a rigidity value that is equal to or higher than the resonance frequency is selected.

  As the rigidity value (elastic modulus: Young's modulus) of the wire harness 61 (or the wire harness complex 60) is increased, the resonance frequency of the electrical connection box 50 with respect to external vibration changes to the high frequency side. Table 1 shows the result of simulating the Young's modulus of the wire harness 61 and the resonance frequency of the electrical junction box 50.

As can be seen from Table 1, when the Young's modulus of the wire harness 61 is doubled, the resonance frequency of the primary mode moves to the high frequency side of about 20 Hz, and when the Young's modulus is 10 times, the resonance frequency of the primary mode is about It moved to the 100 Hz high frequency side. From this result, in order to suppress the resonance of the electrical junction box 50, the configuration of the wire harness complex 60 having a rigidity value that is equal to or higher than the resonance frequency of the target electrical junction box 50 is selected.

As shown in FIG. 4, the wire harness complex selecting unit 13 includes a rigidity value calculating unit 41 and a configuration condition selecting unit 42. The stiffness value calculation unit 41 obtains the relationship between the stiffness value G of the composite system composed of the electrical connection box 50 and the wire harness composite 60 and the resonance frequency f of the composite system, and further, the resonance frequency targeted by the composite system It calculates the target stiffness value G _d of the wire harness complex 60 corresponding to f _d. For example, when the target stiffness value of the composite system is G ′, the density of the wire harness composite 60 is ρ, and the constant term is C, the target stiffness value G ′ of the composite system satisfying the following relational expression (1) is satisfied. and calculates the target stiffness value G _d of the wire harness complex 60 from the target stiffness value G'the calculated composite systems.
(1)

Further, for example, the computer calculates the eigenvalues of the casing 53 of the electrical junction box 50 and the wire harness complex 60, and based on the result, the complex system composed of the electrical junction box 50 and the wire harness complex 60 is predetermined. determining a target stiffness value G _d of the wire harness composite 60 such that above resonance frequency.

Structure condition selection unit 42, the configuration of the wire harness composite 60 such that the target stiffness value G _d or more wire harness complex 60 which is calculated by the rigidity calculation unit 41, stored in the mounting constraint condition storing section 15 The electrical connection box 50 is selected based on the installation constraint conditions.

For example, as shown in FIG. 5 (d), the configuration of the wire harness composite 60 is provided with a support wire 62 made of a rigid body along the wire harness 61, and the wire harness 61 and the support wire 62 are provided in at least two places. A united or combined configuration. That is, the target rigidity value G of the wire harness complex 60 calculated by the rigidity value calculation unit 41 by changing the size and material of the support wire 62 and the number of binding points or the number of binding points and calculating the rigidity value of the wire harness complex 60 by the rigidity value calculation unit 41. _d or more. Examples of the material of the support wire 62 include aluminum (including an aluminum alloy), steel, and fiber reinforced plastic (FRP).

  Further, for example, as shown in FIGS. 6A and 6B, the configuration of the wire harness composite 60 is based on the distance d between the tapes and the tape width w based on how the harness tape 63 is wound around the wire harness 61. The configuration is adjusted. For example, when a harness tape 63 having a tape width w of 19 mm is wound around the wire harness 61 and the distance d between the tapes becomes ½ with the harness tape 63 not overlapping, the bending elasticity of the wire harness composite 60 The rate is 3-4 times. Further, when the harness tape 63 is overlapped and the width of the overlapping portion is overlapped by 1/10 of the distance d between the tapes, the bending elastic modulus of the wire harness composite 60 is 5 to 6 times.

  Finally, the selection / execution unit 14 will be described with reference to FIG. As shown in FIG. 1, the selection / execution unit 14 includes a frequency factor position search unit 21 of the attachment position search unit 11 based on the attachment restriction condition of the electrical connection box 50 stored in the attachment restriction condition storage unit 15. Among the displacement factor position search unit 22 of the attachment position search unit 11, the frequency factor angle search unit 31 of the attachment angle search unit 12, the displacement factor angle search unit 32 of the attachment angle search unit 12, and the wire harness complex selection unit 13 At least one processing unit is selected and executed. The frequency factor position search unit 21 of the attachment position search unit 11 and the displacement factor position search unit 22 of the attachment position search unit 11 are either one and are not selected together. The frequency factor angle search unit 31 of the attachment angle search unit 12 and the displacement factor angle search unit 32 of the attachment angle search unit 12 are either one and are not selected.

  Note that which of these processing units is appropriate is determined appropriately by the person who designs the mounting structure of the electrical junction box based on conditions such as the degree of freedom for attaching the wire harness to the electrical junction box. 14 is input.

  When selecting the processing unit, for example, when the resonance frequency can be sufficiently moved to the high frequency side simply by attaching the wire harness 61 to the attachment position extracted and determined by the frequency factor position search unit 21, the frequency factor position search unit 21. Just run. When the attachment position and the attachment angle are not free, the wire harness composite selection unit 13 is executed to select the configuration of the wire harness composite 60 that has a rigidity value equal to or higher than the target resonance frequency.

  The wire harness 61 (or the wire harness complex 60) is electrically connected based on the mounting position or angle of the wire harness take-out portion 52 determined by the mounting structure design system 10 as described above or the configuration of the wire harness complex 60. By attaching to the box 50, resonance of the electrical junction box with respect to external vibration can be suppressed.

  Therefore, the wire harness 61 (or the wire harness complex 60) is attached to the electrical junction box 50, and the resonance frequency of the composite system composed of the electrical junction box 50 and the wire harness complex 60 is moved to the high frequency side, or resonant. By reducing the displacement caused by the above, the load on the bracket 51 fixed to the vehicle body can be reduced and the life of the electrical junction box 50 can be extended.

  Moreover, when designing the electrical junction box 50, the wire harness 61 (or the wire harness complex 60) can be considered as a part of the structure, so that the design range can be expanded and the design time can be shortened. . In addition, even if the electrical connection box resonates more than expected after mounting on the actual vehicle and the bracket 51 etc. is damaged or malfunctioned, the wire harness can be used without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing the wire 61 (or the wire harness composite 60) and changing the fixing position.

  Next, the procedure of the mounting structure design method for the electrical junction box 50 of the present invention will be described with reference to FIGS. 5, 6, and 7 to 10. The mounting structure design method for the electrical junction box 50 according to the present invention is designed to reduce the resonance of the electrical junction box 50 with respect to external vibration. Or, the configuration of the wire harness composite is examined and determined.

  FIG. 7 is a flowchart showing an example of the procedure of the mounting structure design method for the electrical junction box 50. As shown in FIG. 7, the procedure of the mounting structure design method for the electrical connection box 50 is first performed based on the mounting constraint conditions for mounting the electrical connection box 50 in the external housing, and the mounting position search process and the mounting angle search process. Then, at least one step in the wire harness complex selection step is selected, and the execution order of the selected step is determined (S101). Here, the execution order may be determined in advance.

  Next, the process (S103, S104, S105) selected in step S101 is executed based on the determined order, and the process is terminated when all the selected processes are executed (S102).

  In the attachment position search step (S103), the position range 53a on the electrical connection box 50 to which the wire harness 61 shown in FIG. Among the n positions Pi (1 ≦ i ≦ n) of 53a, the position Pm that most suppresses the resonance with respect to the external vibration of the electrical junction box 50 is searched, and is derived and determined as the attachment position P of the wire harness take-out portion 52. This is a processing step.

  Further, in the attachment angle search step (S104), the wire is formed at n angles θi (1 ≦ i ≦ n) at a predetermined position P on the electrical junction box 50 shown in FIG. In the case where the harness 61 is attached, the angle θm that most suppresses the resonance with respect to the external vibration of the electrical junction box 50 is derived and determined as the attachment angle θ of the wire harness take-out portion 52.

  In addition, the wire harness complex selecting step (S105) is based on the mounting constraint condition, and the composite system including the electrical connection box 50 and the wire harness complex 60 as shown in FIGS. 5 (d) and 6 is targeted. This is a processing step of selecting a configuration of the wire harness composite 60 having a rigidity value that is equal to or higher than the resonance frequency to be performed.

  Next, with reference to FIG.5 (b) and FIG. 8, the detailed procedure of an attachment position search process (S103) is demonstrated. FIG. 8 is a flowchart showing an example of the procedure of the attachment position searching step (S103). As shown in FIG. 8, first, either one of the frequency factor position examination step and the displacement factor location examination step is selected based on the attachment constraint condition for attaching the electrical junction box 50 in the external housing (S201). ).

  Here, the frequency factor position examination step derives and determines the position where the resonance frequency with respect to external vibration of the composite system composed of the electrical connection box 50 and the wire harness 61 becomes the highest frequency side or its vicinity by attaching the wire harness 61. It is a processing step. Further, the displacement factor position examination step is a processing step for deriving and determining a position where the displacement caused by the external vibration in the electrical connection box 50 is the smallest or the vicinity thereof with the wire harness 61 attached.

When selected process is the frequency factor position examination step (S202: Yes), based on the frequency analysis process, to calculate the resonance frequency f ₀ to the external vibration of the electric connection box 50 in a state where not installed wire harness 61 (S203). Next, as a frequency analysis step, the external vibration of the composite system composed of the electrical connection box 50 and the wire harness 61 when the wire harness 61 is attached to various positions Pi within the predetermined position range 53 a on the electrical connection box 50. The resonance frequency f (i) is calculated for (S204).

Next, as a mounting position determining process, a difference Delta] f (i) between the resonance frequency f ₀ which is calculated in step S203 and the resonance frequency f (i) calculated in step S204, the predetermined position range on the electrical connection box 50 The largest difference Δf (m) is selected from the calculated results Pi, and the position Pm at that time or the vicinity of the position Pm is optimally attached to the wire harness take-out portion 52. P is set (S205), and the frequency factor position examination process is terminated.

  When the selected process is the displacement factor position examination process (S202: No), the wire harness 61 is attached to various positions Pi within the predetermined position range 53a on the electrical connection box 50 as the displacement analysis processing process. In this case, the displacement u (i) generated by the composite system including the electrical junction box 50 and the wire harness 61 with respect to external vibration is calculated (S206).

  Next, as the attachment position determination step, the smallest displacement u (m) is selected from the results of the displacement u (i) calculated in step S206, and the position Pm at that time or the vicinity of the position Pm is the optimum wire harness. The attachment position P of the take-out portion 52 is set (S207), and the displacement factor position examination process is terminated.

  Next, with reference to FIG.5 (c) and FIG. 9, the detailed procedure of an attachment angle search process (S104) is demonstrated. FIG. 9 is a flowchart showing an example of the procedure of the attachment angle search step (S104). As shown in FIG. 9, first, one of the frequency factor position examination process and the displacement factor position examination process is selected based on the attachment constraint condition for attaching the electrical junction box 50 in the external housing (S301). ).

  Here, the frequency factor position examination step is a processing step of deriving and determining an angle at which the resonance frequency with respect to external vibration of the electrical connection box 50 is on the highest frequency side or its vicinity by attaching the wire harness 61 in FIG. It is. Further, the displacement factor position examination step is a processing step for deriving and determining an angle at which the displacement generated by the electrical connection box 50 with respect to external vibration becomes the smallest or the vicinity thereof in a state where the wire harness 61 is attached in FIG. It is.

When selected process is the frequency factor position examination step (S302: Yes), based on the frequency analysis process, to calculate the resonance frequency f ₀ to the external vibration of the electric connection box 50 in a state where not installed wire harness 61 (S303). Next, as a frequency analysis step, a resonance frequency f (i) with respect to external vibration of the electrical connection box 50 when the wire harness is attached to the attachment position P at various angles θi is calculated (S304).

Next, as a mounting position determining process, a difference Delta] f (i) between the resonance frequency _{f 0,} which is calculated by the resonance frequency f (i) and step S303 calculated in step S304, is calculated for all angles .theta.i, calculated The largest difference Δf (m) is selected from the results, and the angle θm at that time or the vicinity of the angle θm is set as the optimum mounting angle θ of the wire harness take-out portion 52 (S305), and the frequency factor position examination process is completed. To do.

  When the selected process is a displacement factor position examination process (S302: No), as a displacement analysis process, the outside of the electrical connection box 50 when the wire harness 61 is attached to the attachment position P at various angles θi. A displacement u (i) with respect to the vibration is calculated (S306).

  Next, as the attachment position determination step, the smallest displacement u (m) is selected from the results of the displacement u (i) calculated in step S306, and the angle θm at that time or the vicinity of the angle θm is the optimum wire. The attachment angle θ of the harness take-out portion 52 is set (S307), and the displacement factor position examination step is completed.

Next, with reference to FIG.5 (d), FIG.6 and FIG.10, the detailed procedure of a wire harness complex selection process (S105) is demonstrated. FIG. 10 is a flowchart showing an example of the procedure of the wire harness complex selecting step (S105). As shown in FIG. 10, first, as a rigidity value calculation step, the relationship between the rigidity value G of the composite system composed of the electrical junction box 50 and the wire harness composite 60 and the resonance frequency f of this composite system is obtained. It calculates the target stiffness value _{G d} of the wire harness complex 60 corresponding to the resonance frequency _{f d} of a target of the composite system (S401).

For example, when the target stiffness value of the composite system is G ′, the density of the wire harness composite 60 is ρ, and the constant term is C, the composite system satisfying the relational expression (1) described in FIG. calculates a target stiffness value G', calculates the target stiffness value G _d of the wire harness complex 60 from the target stiffness value G'the calculated composite systems.

  Further, for example, the computer calculates the eigenvalues of the casing 53 of the electrical junction box 50 and the wire harness complex 60, and determines the stiffness value of the wire harness complex 60 that is equal to or higher than a predetermined resonance frequency based on the result. To do.

  Next, as the configuration condition examination step, the configuration of the wire harness composite 60 that is equal to or higher than the rigidity value of the wire harness composite 60 calculated by the rigidity value calculation is examined based on the mounting constraint condition (S402).

  For example, as shown in FIG. 5 (d), the configuration of the wire harness composite 60 is provided with a support wire 62 made of a rigid body along the wire harness 61, and the wire harness 61 and the support wire 62 are provided in at least two places. A united or combined configuration. Further, for example, as shown in FIGS. 6A and 6B, the configuration of the wire harness composite 60 is based on the distance d between the tapes and the tape width w based on how the harness tape 63 is wound around the wire harness 61. The configuration is adjusted.

  The above-described frequency factor position examination step of the attachment position search step, displacement factor position examination step of the attachment position search step, frequency factor angle examination step of the attachment angle search step, displacement factor angle examination step of the attachment angle search step, and wire harness At least one process in the complex selection process is selected, and execution determination is appropriately performed by the person who designs the mounting structure of the electrical junction box, based on conditions such as the degree of freedom for attaching the wire harness to the electrical junction box And

  For example, when the resonance frequency can be sufficiently moved to the high frequency side simply by attaching the wire harness 61 to the attachment position searched in the frequency factor position examination process, only the frequency factor position examination process is executed. Moreover, when there is no freedom in the attachment position and the attachment angle, the wire harness composite selection process is executed to select the configuration of the wire harness composite 60 that has a rigidity value equal to or higher than the target resonance frequency.

  Based on the mounting position or mounting angle of the wire harness take-out portion 52 determined by the mounting structure design method as described above, or the configuration of the wire harness complex 60, the wire harness 61 (or the wire harness complex 60) is connected to the electrical junction box. By attaching to 50, resonance of the electrical junction box with respect to external vibration can be suppressed.

  Therefore, the wire harness 61 (or the wire harness complex 60) is attached to the electrical junction box 50, and the resonance frequency of the composite system composed of the electrical junction box 50 and the wire harness complex 60 is moved to the high frequency side, or resonant. By reducing the displacement caused by the above, the load on the bracket 51 fixed to the vehicle body can be reduced and the life of the electrical junction box 50 can be extended.

  Moreover, when designing the electrical junction box 50, the wire harness 61 (or the wire harness complex 60) can be considered as a part of the structure, so that the design range can be expanded and the design time can be shortened. . In addition, even if the electrical connection box resonates more than expected after mounting on the actual vehicle and the bracket 51 etc. is damaged or malfunctioned, the wire harness can be used without changing the design of the electrical connection box depending on the situation. This can be dealt with by reinforcing the wire 61 (or the wire harness composite 60) and changing the fixing position.

(Example 1) Effect on resonance of electric junction box due to difference in attachment angle The change in resonance with respect to external vibration of the electric junction box was examined by the difference in attachment angle at which the wire harness was attached. Drawing 11 is a figure for explaining the difference in the attachment angle which attaches a wire harness. FIG. 11A is a diagram in which the wire harness 61a is tilted and fixed to the bracket side, and FIG. 11B is a diagram in which the wire harness 61b is tilted and fixed to the side opposite to the bracket.

  The electrical connection box 80 shown in FIG. 11A is composed of a housing 83 and brackets 81a and 81b, and two wire harnesses 61a are attached to the attachment positions P1 and P2 of the electrical connection box 80. Yes. The electric connection box 80 shown in FIG. 11B is composed of a housing 83 and brackets 81a and 81b, and two wire harnesses 61b are attached to the attachment positions P1 and P2 of the electric connection box 80. Yes. As for the approximate dimensions of the housing 83 in FIGS. 11A and 11B, the long side is 160 mm, the short side is 150 mm, and the thickness is 60 mm.

  The approximate lengths of the two brackets 81a and 81b in FIGS. 11 (a) and 11 (b) are 30 mm and 20 mm, respectively. The weight of the housing 83 is about 600 g. The number of wires in the wire harness 61a is 50, and the length is 160 mm. Moreover, the number of electric wires of the wire harness 61b is 76, and the length is 160 mm.

FIG. 12 shows the result of the resonance point measurement of the electrical junction box 80 shown in FIG. Here, as one aspect of the present invention, the resonance acceleration is obtained. As can be seen from FIG. 12, when the wire harness 61a is tilted and fixed to the bracket side as shown in FIG. 11A (solid line), the primary resonance frequency is 55.6 Hz and the resonance acceleration is 45.0 m / s ² . The result was obtained. Further, when the wire harness 61b was tilted and fixed to the side opposite to the bracket as shown in FIG. 11B (dotted line), the primary resonance frequency was 53 Hz and the resonance acceleration was 26 m / s ² .

  From this result, compared with the case where the wire harness 61a is tilted and fixed to the bracket side as shown in FIG. 11A, the wire harness 61b is fixed to the side opposite to the bracket and fixed as shown in FIG. 11B. It has been found that the resonance acceleration is halved in the case of doing so. That is, it was confirmed that the resonance acceleration was reduced depending on the mounting angle of the wire harness coming out of the housing.

(Example 2) Effect on resonance of electric junction box due to difference in configuration of wire harness complex Aluminum wire is attached to the wire harness 61b of Fig. 11 (b) as a support line, and the rigidity value of the wire harness complex is changed. The change of resonance with respect to external vibration of the electrical junction box was investigated. FIG. 13 shows the result of examining the change in resonance with respect to external vibration of the electrical junction box due to the difference in the number of aluminum wires. Here, an aluminum wire having a diameter of 3 mm and a length of 160 mm is used. Moreover, the solid line of FIG. 13 shows the case where no aluminum wire is attached, the dotted line shows the case where one aluminum wire is attached, and the alternate long and short dash line shows the case where three aluminum wires are attached.

As can be seen from FIG. 13, when the aluminum wire is not attached, the primary resonance frequency is 55.6 Hz and the resonance acceleration is 45.0 m / s ^{2. When} the aluminum wire is attached, the primary resonance frequency is 55.0 Hz. The resonance frequency is 60.1 Hz and the resonance acceleration is 45.9 m / s ^{2. When} three aluminum wires are attached, the primary resonance frequency is 65.0 Hz and the resonance acceleration is 43.7 m / s ² . It became. From this result, it was confirmed that the primary resonance frequency moves to the high frequency side by reinforcing the aluminum wire and increasing the effective rigidity of the wire harness.

(Example 3) Effect on resonance of electrical junction box due to difference in attachment position and attachment angle of wire harness (calculation result by computer)
In the electrical junction box composed of the housing and the bracket, the primary resonance frequency of the electrical junction box was examined for four cases with different attachment positions and attachment angles of the wire harness. The approximate dimensions of the housing are 200 mm on a side and 30 mm in thickness. The weight of the housing is about 3.6 kg. The length of the wire harness is 200 mm, and the effective Young's modulus of the wire harness is 500 MPa.

  Table 2 shows the result of the primary resonance frequency of the electrical junction box simulated under the above-described conditions. FIG. 14 is a diagram showing four cases with different attachment positions and attachment angles of the simulated wire harness. In the following angles, the x-axis is 0 °, and the counterclockwise direction is positive.

  Case 1 has a wire harness attached at an angle of + 90 ° in the x direction from the apex B of the housing at an angle of + 90 °, and an angle of −90 ° at a position of 30 mm from the apex D of the housing in the x direction. This is the case with the wire harness attached to the. Case 2 has a wire harness attached at an angle of −90 ° in the x direction from the apex B of the housing at an angle of + 90 °, and an angle of 0 ° at a position of 30 mm from the apex C of the housing in the y direction. This is the case with the attached wire harness.

  Case 3 is attached to the wire harness attached at an angle of + 90 ° from the apex A of the housing at a position of 30 mm in the x direction, and attached at an angle of 0 ° at a position of 30 mm from the apex C of the housing to the y direction. This is the case with an attached wire harness. Case 4 has a wire harness attached at an angle of + 90 ° from the apex A of the housing at a position of 30 mm in the x direction and an angle of −55 ° at a position of 30 mm from the apex C of the housing in the y direction. This is the case with the attached wire harness. Note that “●” in FIG. 14 is a fixing point (a point where the casing is fixed to the bracket).

From the results in Table 2, it was confirmed that the primary resonance frequency varied depending on the attachment position and attachment angle of the wire harness attached to the housing.

(Example 4) Effect on resonance of electrical junction box due to difference in attachment position of wire harness (result by hand calculation)
In the electrical junction box composed of the housing and the bracket, the primary resonance frequency of the electrical junction box was examined for two cases with different attachment positions of the wire harness. Here, in the manual calculation, the position of the fixing point (the point where the housing is fixed to the bracket) and the attachment position of the wire harness are considered to be the same. In the manual calculation, the relational expression (1) described with reference to FIG. 4 is used. The constant term C is determined by factors relating to the dimensions of the housing and fixed boundary conditions. The approximate dimensions of the housing are 200 mm on a side and 30 mm in thickness. The weight of the housing is about 3.6 kg.

  Table 3 shows the result of the primary resonance frequency of the electrical junction box calculated manually under the above-described conditions. Moreover, FIG. 15 is a figure which showed two cases from which the attachment position of the wire harness calculated by hand differs. Note that “●” in FIG. 15 is a fixing point (a point where the casing is fixed to the bracket).

  Case 5 is a case where fixed points, that is, attachment positions of wire harnesses, are provided at vertex A, vertex C, and vertex D of the housing. The case 6 is provided with a fixing point, that is, a wire harness attachment position at a position 100 mm in the y direction from the apex A of the casing, and at a position 100 mm in the y direction from the apex D of the casing and the apex D of the casing. This is the case.

From the results in Table 3, it was confirmed that the primary resonance frequency changes depending on the attachment position of the wire harness attached to the housing.

(Embodiment 5) Effect on resonance of electrical junction box due to difference in rigidity of wire harness In electrical junction box composed of housing and bracket, the primary resonance frequency of electrical junction box for two cases with different stiffness of wire harness I investigated. The approximate dimensions of the housing are 200 mm on a side and 30 mm in thickness. The weight of the housing is about 3.6 kg. In case 4, the length of the wire harness is 200 mm, and the effective Young's modulus of the wire harness is 500 MPa. In case 7, the length of the wire harness is 200 mm, and the effective Young's modulus of the wire harness is 1000 MPa.

  Table 4 shows the result of the primary resonance frequency of the electrical junction box simulated under the above-described conditions. In addition, the attachment position and attachment angle of the wire harness which the case 7 simulated are the same as the case of the case 4 of FIG.

From the results in Table 4, it was confirmed that the primary resonance point moved to the high frequency side by increasing the effective rigidity of the wire harness.

It is a figure for demonstrating the electrical junction box which can apply this invention. It is a figure which shows an example of the detailed system configuration | structure of the attachment position search part 11 of the attachment structure design system 10. FIG. It is a figure which shows an example of the detailed system configuration | structure of the attachment angle search part 12 of the attachment structure design system 10. FIG. It is a figure which shows an example of the detailed system configuration | structure of the wire harness complex selection part 13 in the attachment structure design system 10. FIG. It is a figure for demonstrating the electrical junction box which can apply this invention. It is a figure for demonstrating how to wind the harness tape wound around a wire harness. It is a flowchart figure which shows an example of the procedure of the attachment structure design method of the electrical junction box. It is a flowchart figure which shows an example of the procedure of an attachment position search process (S103). It is a flowchart figure which shows an example of the procedure of an attachment angle search process (S104). It is a flowchart figure which shows an example of the procedure of a wire harness complex selection process (S105). It is a figure for demonstrating the difference in the attachment angle which attaches a wire harness. It is the result of having measured the resonance point of the electrical junction box 80 shown in FIG. It is the result of investigating the change of resonance with respect to external vibration of the electrical junction box due to the difference in the number of aluminum wires. It is the figure which showed four cases from which the attachment position and attachment angle of the simulated wire harness differed. It is the figure which showed two cases from which the attachment position of the wire harness calculated by hand differs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Attachment structure design system 11 Attachment position search part 12 Attachment angle search part 13 Wire harness complex selection part 14 Selection / execution part 15 Attachment restriction condition memory | storage part 21 Frequency factor position search part 22 Displacement factor position search part 23 Reference frequency analysis part 24 Frequency analysis unit 25 Mounting position determining unit 26 Displacement analyzing unit 27 Mounting position determining unit 31 Frequency factor angle searching unit 32 Displacement factor angle searching unit 33 Reference frequency analyzing unit 34 Frequency analyzing unit 35 Mounting angle determining unit 36 Displacement analyzing unit 37 Mounting Angle determination unit 41 Rigidity value calculation unit 42 Configuration condition selection unit

Claims (18)

An electrical junction box for mounting an electrical junction box having a fixed portion for fixing at least one place to an external casing and a wire harness takeout portion from which a wire harness composed of a plurality of electric wire bundles is drawn out in the outer casing. A mounting structure design system,
When the wire harness is attached to the electrical junction box, it is within a predetermined position range on the electrical junction box based on an installation restriction condition for attaching the electrical junction box in the external housing, and is free from external vibration. An attachment position search means for searching for an attachment position of the wire harness take-out portion that most suppresses resonance of the electrical junction box;
When the wire harness is attached to the electrical junction box, the wire harness is taken out to suppress the resonance of the electrical junction box with respect to external vibration most at a predetermined attachment position on the electrical junction box based on the attachment constraint condition. A mounting angle searching means for searching for a mounting angle of the part;
When the wire harness is attached to the electrical junction box, based on the attachment constraint condition, the wire harness composite having undergone a stiffness value change of the wire harness that most suppresses resonance of the electrical junction box with respect to external vibration. A wire harness complex selecting means for selecting a configuration;
Selection / execution means for selecting and executing at least one of the attachment position search means, the attachment angle search means, and the wire harness complex selection means based on the attachment constraint condition;
With
The attachment position search means includes
A reference frequency analysis means for calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in a state where there is no wire harness ;
When the wire harness is attached to various positions Pi within a predetermined position range on the electrical junction box, the resonance frequency f (i) that the composite system composed of the electrical junction box and the wire harness exhibits against external vibration. Frequency analysis means for calculating
Various positions Pm as the largest difference value among the results of calculating the difference Delta] f (i) between the resonance frequency f ₀ which is calculated from the reference frequency analysis means and the resonance frequency f (i) calculated from the frequency analysis means An attachment position determining means for extracting the position Pm or the vicinity of the position Pm as the attachment position of the wire harness take-out portion;
With
Search or selection result by at least one of the attachment position search means, the attachment angle search means, and the wire harness complex selection means selected and executed by the selection / execution means, and the attachment An electrical connection box mounting structure design system, wherein the mounting position or mounting angle of the wire harness take-out portion or the configuration of the wire harness complex is determined based on a constraint condition. The attachment position search means includes
Displacement caused by external vibration of resonance frequency f when the wire harness is mounted at various positions Pi within a predetermined position range on the electrical connection box, the composite system including the electrical connection box and the wire harness. displacement analysis means for calculating u (i);
The position Pm having the smallest displacement value among the results of the displacement u (i) calculated by the displacement analyzing means is extracted from the various positions Pi, and the extracted position Pm or the vicinity of the position Pm is extracted from the position Pm. Mounting position determining means for determining the mounting position of the wire harness take-out part;
The electrical connection box mounting structure design system according to claim 1, comprising: The mounting angle search means includes
A reference frequency analysis means for calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in a state where there is no wire harness ;
Resonance frequency f (i) that the composite system composed of the electrical junction box and the wire harness exhibits against external vibration when the wire harness is attached to the predetermined position P on the electrical junction box at various angles θi. Frequency analysis means for calculating
Various angles θm as a largest difference value among the results of calculating the difference Delta] f (i) between the resonance frequency f ₀ which is calculated from the reference frequency analysis means and the resonance frequency f (i) calculated from the frequency analysis means Mounting angle determining means for extracting from the angle θi, and determining the extracted angle θm or the vicinity of the angle θm as the mounting angle of the wire harness take-out portion;
The electrical connection box mounting structure design system according to claim 1, comprising: The mounting angle search means includes
In the case where the wire harness is attached at a predetermined position P on the electrical junction box at various angles θi, the electrical resistance against external vibration at the resonance frequency f of the composite system composed of the electrical junction box and the wire harness. Displacement analysis means for calculating the displacement u (i) generated by the connection box;
The angle θm that is the smallest displacement value among the results of the displacement u (i) calculated by the displacement analysis means is extracted from the various angles θi, and the extracted angle θm or the vicinity of the angle θm is Mounting angle determining means for determining the mounting angle of the wire harness take-out portion;
The electrical connection box mounting structure design system according to claim 1, comprising: The wire harness complex selecting means is:
The relationship between the effective stiffness value G of the composite system composed of the electrical junction box and the wire harness composite and the resonance frequency f of the composite system is obtained, and further corresponds to the target resonance frequency f _d of the composite system. and stiffness value calculating means for calculating a stiffness value G _d of the wire harness complex,
Said wire harness complex the wire harness complexes more rigidity stiffness values G _d is obtained a configuration which is calculated by the rigidity calculation means, and structure condition selecting means for selecting, based on said mounting constraints,
The electrical connection box mounting structure design system according to claim 1, comprising: The configuration of the wire harness complex includes the wire harness and a support line made of a rigid body that is provided along the wire harness and bound or combined with the wire harness in at least two places.
The structure condition selecting means, as the stiffness value above stiffness value G _d of the wire harness complexes calculated by the rigidity calculation means is obtained, the dimensions and material of the support wire, as well as binding portion or the number of binding points 6. The electrical connection box mounting structure design system according to claim 5 , wherein the number is adjusted . The configuration of the wire harness complex includes the wire harness and a harness tape wound around the wire harness.
The attachment of the electrical junction box according to claim 5 , wherein the configuration condition selection unit adjusts a winding method of the harness tape around the wire harness based on an inter-tape distance and a tape width of the harness tape . Structural design system. The rigidity value calculating means is set such that the resonance frequency of the composite system is f, the effective stiffness value of the composite system is G, the effective density of the composite system is ρ, and the constant term is C.
As basic equations, the the effective rigidity G of the composite system based on the correlation between the rigidity G ₀ of the wire harness complex, calculating the stiffness value G _d of the wire harness complexes targeted The electrical connection box mounting structure design system according to any one of claims 5 to 7 . Using the computer, an electrical junction box having a fixed portion that fixes at least one place to the external housing and a wire harness take-out portion from which a wire harness composed of a plurality of electric wire bundles is drawn is mounted in the external housing. An electrical junction box mounting structure design method for
The computer is
(A1) Based on the mounting constraint condition of the electrical connection box for mounting in the external casing acquired from the mounting condition storage unit, (b1) the mounting constraint when the wire harness is mounted on the electrical connection box Searching for the attachment position of the wire harness take-out portion that most suppresses resonance of the electrical junction box with respect to external vibrations within a predetermined range of positions on the electrical junction box based on conditions; and (b2) the wire When the harness is attached to the electrical junction box, the wire harness take-out portion that most suppresses the resonance of the electrical junction box with respect to external vibration at a predetermined attachment position on the electrical junction box based on the attachment constraint condition. Searching for the mounting angle; and (b3) taking the wire harness into the electrical junction box. From the step of selecting the configuration of the wire harness composite that has undergone the rigidity value change of the wire harness that most suppresses the resonance of the electrical junction box with respect to external vibration based on the mounting constraint condition. Selecting at least one process;
(A2) Execution order in which all processes selected by the step (a1) among the process (b1), the process (b2), and the process (b3) are determined based on the attachment constraint condition Steps to be performed according to
(A3) determining the attachment position or attachment angle of the wire harness take-out portion, or the configuration of the wire harness complex, based on the result executed in step (a2) and the attachment constraint condition;
With
The step (b1)
(C1) calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in the absence of the wire harness ;
(C2) Resonance frequency exhibited by the composite system composed of the electrical connection box and the wire harness with respect to external vibration when the wire harness is attached to various positions Pi within a predetermined position range on the electrical connection box calculating f (i);
(C3) the largest difference value among the step (c2) calculated resonance frequency f (i) and the step (c1) the difference Delta] f (i) was calculated result of the resonance frequency f ₀ which is calculated from from Extracting the position Pm from the various positions Pi, and determining the extracted position Pm or the vicinity of the position Pm as an attachment position of the wire harness extraction portion;
An electrical connection box mounting structure design method characterized by comprising: The step (b1)
(D1) When external vibration is generated at a resonance frequency f of a composite system including the electrical connection box and the wire harness when the wire harness is attached to various positions Pi within a predetermined position range on the electrical connection box. Calculating the displacement u (i) that occurs with respect to,
(D2) The position Pm having the smallest displacement value among the results of the displacement u (i) calculated in the step (d1) is extracted from the various positions Pi, and the extracted position Pm or the position Pm The step of determining the vicinity of the wire harness takeout position as an attachment position;
The mounting structure design method for an electrical junction box according to claim 9 . The step (b2)
(E1) calculating a resonance frequency f ₀ with respect to external vibration of the electrical junction box in the absence of the wire harness ;
(E2) Resonant frequency f that the composite system composed of the electrical junction box and the wire harness exhibits against external vibration when the wire harness is attached at a predetermined position P on the electrical junction box at various angles θi. Calculating (i);
(E3) the largest difference value among the step (e2) calculated resonance frequency f (i) and the step (e1) difference Delta] f (i) was calculated result of the resonance frequency f ₀ which is calculated from from Extracting the angle θm from the various angles θi, and determining the extracted angle θm or the vicinity of the angle θm as an attachment angle of the wire harness take-out portion;
The mounting structure design method for an electrical junction box according to claim 9 . The step (b2)
(F1) With respect to external vibration at a resonance frequency f of a composite system composed of the electrical connection box and the wire harness when the wire harness is attached at a predetermined position P on the electrical connection box at various angles θi. Calculating the displacement u (i) generated by the electrical junction box;
(F2) The angle θm that is the smallest displacement value among the results of the displacement u (i) calculated in the step (f1) is extracted from the various angles θi, and the extracted angle θm or the angle θm Determining the attachment angle of the wire harness take-out portion in the vicinity of
The mounting structure design method for an electrical junction box according to claim 9 . The step (b3)
(G1) The relationship between the effective stiffness value G of the composite system composed of the electrical junction box and the wire harness composite and the resonance frequency f of the composite system is obtained, and the target resonance frequency f _{d of the} composite system is obtained. calculating a stiffness value G _d of the wire harness complex corresponding to,
(G2 ₎ selecting a configuration of the wire harness complex that can obtain a rigidity value equal to or higher than the rigidity value Gd of the wire harness complex calculated in the step (g1) based on the mounting constraint condition;
The mounting structure design method for an electrical junction box according to claim 9 . The configuration of the wire harness complex includes the wire harness and a support line made of a rigid body that is provided along the wire harness and bound or combined with the wire harness in at least two places.
Wherein step (g2), the stiffness values described above stiffness value G _d of the wire harness complex calculated by step (g1) is obtained, the dimensions and materials of the support wire, as well as binding portion or the number of binding points 14. The method for designing an attachment structure for an electrical junction box according to claim 13 , wherein the number is adjusted . The configuration of the wire harness complex includes the wire harness and a harness tape wound around the wire harness.
The electrical connection box attachment according to claim 13 , wherein the step (g2) adjusts a winding method of the harness tape around the wire harness based on a distance between tapes and a tape width of the harness tape . Structural design method. In the step (g1), when the resonance frequency of the composite system is f, the effective stiffness value of the composite system is G, the effective density of the composite system is ρ, and the constant term is C,
As basic equations, the the effective rigidity G of the composite system based on the correlation between the rigidity G ₀ of the wire harness complex, calculating the stiffness value G _d of the wire harness complexes targeted The mounting structure design method for an electrical junction box according to any one of claims 13 to 15 . An electrical junction box for mounting an electrical junction box having a fixed portion for fixing at least one place to an external casing and a wire harness takeout portion from which a wire harness composed of a plurality of electric wire bundles is drawn out in the outer casing. A program that causes a computer to execute a process of mounting structure design,
A program for causing a computer to execute processing for realizing each means of the electrical connection box mounting structure design system according to any one of claims 1 to 8 . An electrical junction box for mounting an electrical junction box having a fixed portion for fixing at least one place to an external casing and a wire harness takeout portion from which a wire harness composed of a plurality of electric wire bundles is drawn out in the outer casing. Mounting structure,
The wire based on the mounting position or mounting angle of the wire harness take-out portion determined by the electrical connection box mounting structure design system according to any one of claims 1 to 8, or the configuration of the wire harness complex Electric junction box mounting structure, characterized by attaching a harness .