JP5330789B2 - Buffer parts analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a modeling of a buffer member for obtaining a highly precise analytic result, using a simple approximation method. <P>SOLUTION: In creating a model 60 for analysis of a top mount 17, an internal cylinder 17a and an external cylinder 17b which are rigid members are modeled by solid elements 61 and 62, and a mount rubber 17c which is an elastic member is modeled by three or more (for example, four) spring elements 63, so that it is possible to acquire a high-precision analysis result by a simple approximation method. That is, the solid elements 61 and 62 are restrained by the three or more spring elements 63 so that it is attainable to apply a pseudo rotational restraining force to the model 60 for analysis by a simple approximation. Hence, it is accurate analysis, such as characteristics, other than an axial O direction (expansion direction) as the characteristics of the twisting direction or thrust direction with respect to an axis O of a top mount 17. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for modeling a shock absorbing component in which an elastic member is interposed between a pair of rigid members facing each other, such as an engine mount applied to a vehicle and a top mount of a suspension device.

  In general, many cushioning parts typified by cushion rubber parts such as engine mounts and top mounts of suspension devices are used in vehicles. Therefore, for example, when performing CAE (Computer Aided Engineering) analysis at the time of such a vehicle collision, in order to improve the analysis accuracy of the vehicle body deformation and the vehicle body acceleration, in the vehicle model for analysis, each buffer component is It is important to model accurately in a state close to a real machine.

  In this case, in particular, in the vehicle model for collision analysis, it is necessary to model the shock-absorbing part in consideration of the analysis of the characteristic in the direction that does not need to be taken into consideration during normal traveling. For example, when modeling the top mount of a suspension apparatus, it is necessary to analyze not only the characteristics of the suspension apparatus in the axial direction (stretching direction) but also the characteristics in the torsional direction and the twisting direction with respect to the shaft. .

As a method for modeling this type of shock absorbing component, for example, Patent Document 1 discloses a plurality of elastic elements that are divided into at least three layers in the radial direction and divided at equal angles along the circumferential direction. A technique for modeling a cylindrical rubber bush member by elastically coupling a certain primary hexa element (solid element) is disclosed.
JP 2004-46495 A

  However, as in the technique disclosed in Patent Document 1 described above, in order to model a cushion rubber or the like using a solid element, it is necessary to acquire detailed actual machine material characteristics. Also, when analyzing soft cushion rubber etc. using solid elements, for example, errors are likely to occur in scenes where the nodes are bottomed out, and analysis conditions etc. are set in detail to ensure calculation stability There is a need to. Furthermore, in order to reproduce the initial load state generated in the vehicle mounted state, it is necessary to analyze the stress state of each element in advance.

  Therefore, when modeling a vehicle on which a considerable number of cushioning parts having different characteristics for each part are mounted, approximating all cushion rubbers and the like with solid elements is complicated and various settings work is not practical.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an analysis device for a shock absorber that can obtain an accurate analysis result by a simple approximation method.

A shock absorber analyzing apparatus according to an aspect of the present invention is a shock absorber analyzing apparatus in which an elastic member is interposed between a pair of rigid members facing each other, and each of the rigid members is a solid element or a shell element. Three or more spring elements having a three-axis translation characteristic which are modeled and the elastic members are arranged two-dimensionally or three-dimensionally between the solid elements or the shell elements modeling the rigid members. It is equipped with a model creation unit for modeling with .

According to the shock absorber analyzing apparatus of the present invention, an accurate analysis result can be obtained by a simple approximation method.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings relate to an embodiment of the present invention, FIG. 1 is a schematic configuration diagram showing a main part of a vehicle body, FIG. 2 is a cross-sectional perspective view showing a top mount main part of a suspension device, and FIG. 3 is a main part of a front side engine mount. 4 is a functional block diagram showing a schematic configuration of the analysis apparatus, FIG. 5 is a perspective view showing a top mount analysis model, and FIG. 6A is a side view showing the top mount analysis model. FIG. 7B is an explanatory view showing an example of the deformation state of the analysis model, FIG. 7A is a side view showing the analysis model of the front engine mount, and FIG. FIG. 8 is a side view showing a modified example of the top mount analysis model.

  In FIG. 1, reference numeral 1 denotes a vehicle body. An engine room 1 a is provided at the front part of the vehicle body 1, and the rear part of the engine room 1 a is partitioned from the cabin 2 by a toe board 3. A pair of left and right front side frames 4L, 4R are disposed on both sides of the engine room 1a in the vehicle width direction. The rear portions of the side frames 4L and 4R extend downward and rearward along the inclination of the toe board 3, and are front end portions of the side sills 5L and 5R disposed on both sides of the floor panel (not shown) in the vehicle width direction. Are connected to each other.

  The front end portions of the front side frames 4L and 4R are connected to each other via a cross member 6 such as a front cross member or a bumper beam. Further, a subframe 7 is disposed below the engine room 1a. The sub-frame 7 is arranged below the front side frames 4L and 4R and is connected to the pair of left and right sub-side members 8L and 8R extending in the longitudinal direction of the vehicle body and the front ends of the sub-side frames 8L and 8R. The sub-front cross member 9 and the sub-rear cross member 10 connected to the rear ends of the sub-side frames 8L and 8R are formed in a frame shape. Further, the front end portions of the sub-side frames 8L and 8R are connected to the front side frames 4L and 4R via the sub-frame support bracket 11, and the rear end portions are directly fixed to the front side frames 4L and 4R.

  A power unit 14 configured by combining an engine body 12 and a transmission 13 is mounted in the engine room 1a. In the present embodiment, a horizontally opposed engine is shown as the engine body 12, and the transmission 13 is connected to the rear portion of the engine body 12 and extends rearward of the vehicle body. The center of gravity of the power unit 14 is at the substantially central portion in the vehicle width direction on the engine body 12 side, and the three positions of the front end portion and both side portions surrounding the center of gravity are connected via the engine mounts 15F, 15L, and 15R as buffer parts. The frame 7 is supported and fixed.

  A suspension device 16 for the front wheels is disposed on the outer side in the vehicle width direction of each front side frame 4L, 4R, and a top mount 17 as a cushioning part provided on the top of the suspension device 16 is a vehicle side member ( (Not shown).

  Here, for example, as shown in FIG. 2, the top mount 17 is fastened and fixed to the vehicle body side member at the outer peripheral side of the inner cylinder 17a and the inner cylinder 17a as a rigid member fixed to the upper part of the shock absorber 16a. An outer cylinder 17b as a rigid member and a mount rubber 17c as an elastic member interposed between the inner cylinder 17a and the outer cylinder 17b are configured.

  For example, as shown in FIGS. 1 and 3, the front-side engine mount 15 </ b> F includes a mounting bracket 20 fixed to the engine body 12, an arm member 21 connected to the mounting bracket 20, and a tip of the arm member 21. And a mount member 22 as a cushioning part fixed to the portion. The mount member 22 is interposed between the outer cylinder 22a as a rigid member, the inner cylinder 22b as a rigid member coaxially disposed on the inner periphery of the outer cylinder 22a, and both the cylinders 22a and 22b. And a cushion rubber 22c as an elastic member. On the other hand, a vehicle body side bracket 23 is fixed at the center of the sub-front cross member 9 in the vehicle width direction. The vehicle body side bracket 23 has a pair of bracket members 24 that are opposed to each other at a predetermined interval, and a support hole 24 a is formed in the upper part of both the bracket members 24. Then, the mount member 22 is inserted between the bracket members 24, and is screwed into the support shaft 25 inserted into the inner cylinder 22b and the support hole 24a, and the screw provided at the tip of the support shaft 25. The mount member 22 is rotatably supported by the vehicle body side bracket 23 via the nut 26 that performs the above operation.

  For example, as shown in FIG. 4, the analysis device 50 that performs vehicle collision analysis or the like includes an input unit 51 for inputting information necessary to model each component of the vehicle, and an input unit. Based on the input information about each member from 51, a model creating unit 52 for modeling each member to be analyzed into an analysis model such as an FEM model, and a condition for simulation such as collision analysis are input. A condition input unit 53 for performing analysis, a simulation execution unit 54 for performing an analysis by a finite element method or the like by giving the condition input by the condition input unit 53 to the analysis model created by the model creation unit 52, and executing the simulation The main part is configured with an output unit 55 that performs an output process such as graphic display of the analysis result of the unit 54 on a display or printing of data with a printer. .

  In such an analysis apparatus 50, the model creating unit 52 approximates the shock absorbing component using a pair of solid elements or shell elements and three or more spring elements.

  More specifically, for example, as shown in FIG. 5, the model creation unit 52 creates a pair of rigid members, an inner cylinder 17 a and an outer cylinder, when creating the analysis model 60 of the top mount 17 of the suspension device 16. 17b is modeled using the solid elements 61 and 62, and the mount rubber 17c, which is an elastic member interposed between them, is modeled using the four spring elements 63.

  In this case, as shown in FIGS. 5 and 6A, the inner cylinder 17a and the outer cylinder 17b in a state where no load is applied are perpendicular to the axis O along the direction of expansion and contraction of the suspension device 16. It is approximated by a flat element, and it is desirable that the opposing surfaces of the solid elements 61 and 62 are arranged in parallel to each other. The spring elements 63 are preferably arranged orthogonally to the opposing surfaces of the solid elements 61 and 62, and the ends are coupled in the normal direction. Further, as shown in FIG. 5, the spring elements 63 are desirably arranged at equal intervals on the same circumference centered on the axis O. Further, it is desirable that each spring element 63 is equally provided with the translational characteristics in the respective axial directions as the entire mount rubber 17c. That is, if the translation characteristics Fa = (fax, fay, faz) in the respective axial directions of the mount rubber 17c as a whole, in the illustrated example, the translation characteristics Fm ′ = (fmx / 4, fmy / 4, fmz / 4) are preferably set.

  Further, for example, as shown in FIG. 7, the model creating unit 52 creates a pair of rigid members outer cylinder 22a and inner cylinder 22b as solid elements 71, when creating a model 70 for analysis of the front engine mount 15F. Each of the cushion rubbers 22c interposed between them is modeled by a multi-layer (for example, three layers) spring element 73 having a group of four.

  In this case, the outer cylinder 22a and the inner cylinder 22b in a state where no load is applied are approximated by concentric cylindrical elements, and the opposing surfaces of the solid elements 71 and 72 are arranged so as to be parallel to each other. It is desirable. The spring elements 73 are preferably arranged orthogonally to the opposing surfaces of the solid elements 71 and 72 and the ends thereof are coupled in the normal direction. Further, as shown in FIG. 7A, the spring elements 73 constituting each group are arranged radially at regular intervals with respect to the central axis O ′ of the solid elements 71 and 72, and FIG. ), It is desirable that the groups are arranged at equal intervals along the central axis O ′. In addition, it is desirable that each spring element 73 is equally provided with the translational characteristics in the respective axial directions of the cushion rubber 22c as a whole. That is, assuming that the translation characteristic Fb = (fbx, fby, fbz) as a whole of the cushion rubber 22c, in the illustrated example, the translation characteristic Fb ′ = (fbx / 12, fby / 12, fbz /) of each spring element 73. 12) is preferably set.

  According to such an embodiment, when the analysis model 60 of the top mount 17 is created, the inner cylinder 17a and the outer cylinder 17b that are rigid members are modeled by the solid elements 61 and 62, respectively, and the mount rubber that is an elastic member By modeling 17c with three or more (for example, four) spring elements 63, an accurate analysis result can be obtained by a simple approximation method. That is, by connecting the solid elements 61 and 62 so as to constrain them by three or more spring elements 63, a pseudo rotational restraining force can be applied to the analysis model 60 by simple approximation. Therefore, for example, characteristics other than the direction of the axis O (stretching direction) such as the characteristics of the top mount 17 with respect to the axis O and the direction of twisting can be accurately analyzed (for example, FIG. b)). Further, by approximating the mount rubber 17c with a simple combination of spring elements 63, it is not necessary to perform complicated detailed work or the like as compared with the case of approximating with a solid element or the like, and stable without causing an error or the like. Analysis can be realized.

  In this case, the opposing surfaces of the solid elements 61 and 62 are arranged in parallel, and the spring elements 63 are arranged orthogonally to these opposing surfaces, so that the actual material characteristics of the top mount 17 (that is, in the respective axial directions). The translation characteristics (fax, fay, faz)) can be easily divided and applied to each spring element 63. Furthermore, if the spring elements 63 are arranged at equal intervals on the same circumference, the distribution of the actual characteristics of the top mount 17 to the spring elements 63 can be easily set. Then, by giving the actual machine characteristics of the top mount 17 equally to each spring element 63, the analysis model 60 of the top mount 17 can be created more easily.

  Of course, the analysis model 70 of the front-side engine mount 15F described above can achieve the same effects as the analysis model 60 of the top mount 17.

  Here, in the above-described embodiment, an example in which the elastic member is approximated by only three or more spring elements has been described. However, by using a damper element together with the spring element, the elastic member is more closely approximated to the actual machine. Is also possible. In this case, for example, when approximating the top mount 17, as shown in FIG. 8A, it is possible to interpose a damper element 64 in series with each spring element 63. Further, for example, as shown in FIG. 8B, a damper element 64 can be interposed in parallel with each spring element 63. Then, as shown in FIGS. 8A and 8B, the elastic member is approximated more faithfully by appropriately inserting a damper element 64 according to the characteristics of the elastic member (top mount 17). It becomes possible to do.

  In the above-described embodiment, an example in which the top mount 17 and the front-side engine mount 15F are modeled as buffer parts has been described. However, the present invention is not limited to this, and a similar modeling method is used. Of course, the above may be applied to various other buffer parts. For example, the same modeling method can be suitably applied to the left and right engine mounts 15L and 15R.

Schematic configuration diagram showing the main parts of the car body Cross-sectional perspective view showing the main part of the top mount of the suspension device Exploded perspective view showing the main part of the front engine mount Functional block diagram showing the schematic configuration of the analyzer Perspective view showing top mount analysis model (A) is a side view which shows the model for analysis of a top mount, (b) is explanatory drawing which shows an example of the pressure and deformation | transformation state of a model for analysis (A) is a side view which shows the model for analysis of a front side engine mount, (b) is II sectional drawing of (a). Side view showing a variation of the top mount analysis model

Explanation of symbols

1 ... Body 1
DESCRIPTION OF SYMBOLS 1a ... Engine room 2 ... Cabin 3 ... Toe board 4L, 4R ... Front side frame 5L, 5R ... Side sill 6 ... Cross member 7 ... Sub frame 8L, 8R ... Sub side member 9 ... Sub front cross member 10 ... Sub rear cross member 11 ... Sub-frame support bracket 12 ... Engine body 13 ... Transmission 14 ... Power unit 15F, 15L, 15R ... Engine mount (buffer parts)
16 ... Suspension device 16a ... Shock absorber 17 ... Top mount (buffer part)
17a ... Inner cylinder (rigid member)
17b ... outer cylinder (rigid member)
17c: Mount rubber (elastic member)
20 ... Mounting bracket 21 ... Arm member 22 ... Mount member 22a ... Outer cylinder (rigid member)
22b ... Inner cylinder (rigid member)
22c ... Cushion rubber (elastic member)
DESCRIPTION OF SYMBOLS 23 ... Vehicle body side bracket 24 ... Bracket member 24a ... Support hole 25 ... Support shaft 26 ... Nut 50 ... Analyzing device 51 ... Input part 52 ... Model creation part 53 ... Condition input part 54 ... Simulation execution part 55 ... Output part 60 ... Analysis Model 61, 62 ... Solid element 63 ... Spring element 64 ... Damper element 70 ... Analytical model 71, 72 ... Solid element 73 ... Spring element

Claims (5)

A shock absorber analyzing device in which an elastic member is interposed between a pair of rigid members facing each other,
Each of the rigid members is modeled by a solid element or a shell element, and the elastic member is arranged in a two-dimensional or three-dimensional manner between the solid element or the shell element that models each of the rigid members. An apparatus for analyzing a shock absorbing component, comprising a model creation unit that models with three or more spring elements having a translational characteristic in a direction . The model creating unit arranges the opposing surfaces of the solid element or the shell element in which the rigid members are modeled in parallel,
Analyzer buffering component of claim 1, wherein the orthogonal arrangement of the respective spring element modeling said resilient member against the opposing surface. 3. The shock absorber analyzing apparatus according to claim 1 , wherein the model creating unit arranges the spring elements that model the elastic member at equal intervals on the same circumference. 4. The said model creation part provided the said translation characteristic of each axial direction of the said elastic member equally to each said spring element modeled, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. The shock absorber analysis device described in 1. It said model creating unit, analyzer buffering component according to any one of claims 1 to 4, characterized in that modeling the elastic member comprises a damper element added to the spring element.

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