JP5262488B2 - Method for creating assembly model and computer program for creating assembly model - Google Patents

Description

  The present invention relates to a tire / internal structure assembly in which an internal structure having a sound absorbing function is accommodated in a tire, and to an analysis model that can be analyzed by a computer.

  It has been proposed to reduce the resonance sound of air present in the cavity of a tire by housing a sound absorber inside the tire (for example, Patent Document 1). Patent Document 2 discloses a technique for evaluating tire characteristics by computer simulation using a finite element method.

JP-A-7-52616 JP 2006-72893 A

  By the way, when evaluating the characteristics of the assembly in which the sound absorber is housed in the tire as disclosed in Patent Document 1, the sound absorber, tire deformation, stress state, and the like when the tire is rotating are measured. It is difficult to ask for. Therefore, in such a case, a tire / internal structure assembly model configured by storing an internal structure model in which a sound absorber is modeled in the tire model is created, and the created tire / internal structure Perform rolling analysis to rotate the assembly model.

  However, when the internal structure is stored inside the tire, the internal structure is deformed. Accordingly, strain and stress are generated in the internal structure, and the tire that comes into contact with the internal structure is also affected. When the state in which the internal structure is stored inside the tire is simply modeled as an analytical model, it is difficult to reproduce the deformation state including the stress state of the internal structure, and there is room for improvement in this respect. The present invention has been made in view of the above, and in creating a tire / internal structure assembly model that can be analyzed by a computer and configured to contain an internal structure model in the tire model, The object is to reproduce the state of deformation of the structure.

  In order to solve the above-described problems and achieve the object, a method for creating an assembly model according to the present invention is a tire model that can be analyzed by a computer by analyzing the tire and an internal structure housed in the tire. And a procedure for creating a computer-analyzable fitting model used when arranging the internal structure model inside the tire model, and creating the fitting model into the internal structure A procedure for placing the internal structure model in the tire model by contacting the body model and moving the mounting tool model toward the inside of the tire model; and the mounting tool model and the internal structure A step of releasing contact with the model, and a step of setting contact between the internal structure model and the tire model. And wherein the door.

  As a preferred aspect of the present invention, in the method for creating the assembly model, the shape of the wearing tool model is an annular shape, and at least one of a circumferential direction of the wearing tool model and an axial direction of the wearing tool model. It is desirable that it is composed of two or more parts.

  As a preferred aspect of the present invention, in the method of creating the assembly model, it is desirable that the mounting tool model moves in at least one of an axial direction and a radial direction.

  As a preferred aspect of the present invention, in the assembly model creation method, it is desirable that a part of the mounting tool model is an analytical model of at least a part of the tire model or the inner surface of the tire.

  As a preferred aspect of the present invention, in the method of creating the assembly model, in the procedure of placing the internal structure model in the tire model, the mounting tool model is positioned from a position that does not interfere with the internal structure model. It is desirable to start moving.

  In order to solve the above-described problems and achieve the object, an assembly model creation computer program according to the present invention causes a computer to execute the assembly model creation method.

  In the simulation using a computer, when creating a tire / internal structure assembly model that can be analyzed by a computer, the internal structure model is configured by accommodating the internal structure model inside the tire model. Can be reproduced.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited by the following contents. The following constituent elements include those that can be easily assumed by those skilled in the art and those that are substantially the same. The application target of the present invention is not limited to pneumatic tires, and the present invention can be applied to tires in general.

  FIG. 1 is a cross-sectional view showing a meridional section through a rotation axis of a tire / internal structure assembly. FIG. 2 is a schematic view showing an example in which an internal structure is arranged inside the tire. The tire / internal structure assembly 100 is configured by disposing the internal structure 10 inside the tire 1. A carcass 2, a belt 3, a belt cover 4, and a bead core 5 appear on the meridional section of the tire 1. The tire 1 is a composite material structure in which rubber as a base material is reinforced by a reinforcing cord such as a carcass 2, a belt 3, or a belt cover 4 as a reinforcing material. Here, a layer made of a cord material such as a metal fiber or an organic fiber, such as the carcass 2, the belt 3, and the belt cover 4, is referred to as a cord layer.

  The carcass 2 is a strength member that serves as a pressure vessel when the tire 1 is filled with air. The carcass 2 supports a load by its internal pressure and withstands a dynamic load during traveling. The belt 3 is a layer of reinforcing cords in which rubberized cords arranged between the cap tread and the carcass 2 are bundled. In the case of a bias tire, it is called a breaker. In the radial tire, the belt 3 plays an important role as a shape retention and strength member.

  A belt cover 4 is disposed on the grounding surface side of the belt 3. The belt cover 4 is formed by arranging, for example, organic fiber materials in layers, and has a role as a protective layer for the belt 3 and a role as a reinforcing layer for the belt 3. The bead core 5 is a bundle of steel wires that supports the cord tension generated in the carcass 2 by internal pressure. The bead core 5 becomes a strength member of the tire 1 together with the carcass 2, the belt 3, the belt cover 4, and the tread. A groove 7 is formed on the ground surface G side of the cap tread 6. This improves drainage during rainy weather. The side portion of the tire 1 is called a sidewall 8 and connects between the bead core 5 and the cap tread 6. Further, a shoulder portion Sh is provided between the cap tread 6 and the sidewall 8.

  The internal structure 10 is a sound absorbing material, and is disposed in a space surrounded by an inner peripheral surface of the tire 1 and a rim to which the tire 1 is assembled, that is, inside the tire 1 and exists inside the tire 1. Reduce the resonance of air. The internal structure 10 is, for example, a material having sound absorption characteristics, such as urethane or sponge. As a material constituting the internal structure 10, a porous material is particularly preferable. As shown in FIG. 2, the internal structure 10 may be continuous toward the circumferential direction of the tire 1 or may be discontinuous. Next, an apparatus for executing the assembly model creation method according to the present embodiment will be described.

  FIG. 3 is an explanatory diagram showing a configuration of an assembly model creation method according to the present embodiment. An assembly model creation apparatus (hereinafter referred to as an assembly model creation apparatus) 50 shown in FIG. 3 executes the assembly model creation method according to the present embodiment. Here, the assembly is the tire / internal structure assembly 100 shown in FIGS. 1 and 2. The assembly model creation apparatus 50 includes a processing unit 50p and a storage unit 50m. The processing unit 50p and the storage unit 50m are connected via an input / output unit (I / O) 59.

  The processing unit 50p includes a model creation unit 51 and an analysis unit 52. These execute the assembly model creation method according to the present embodiment. The model creation unit 51, the analysis unit 52, and the condition determination unit 53 are connected to an input / output unit 59, and are configured to exchange data with each other.

Further, the terminal device 60 is connected to the input / output unit 59, and configures data necessary for executing the assembly model creation method according to the present embodiment, for example, the tire 1 and the internal structure 10. The physical property value of the material, the physical property value of the fiber material, the boundary condition in the analysis, the running condition, and the like are given to the assembly model creation device 50 by the input / output device 61 connected to the terminal device 60. Further, the tire model creation data is received from the assembly model creation device 50 and the analysis result is displayed on the display device 62 connected to the terminal device 60. Furthermore, various data servers 64 ₁ , 64 _2, etc. are connected to the input / output unit 59 via the network 63. In executing the assembly model creation method according to this embodiment, the processing unit 50p can be configured to use various databases stored in the various data servers 64 ₁ , 64 _2, and the like.

The storage unit 50m stores a computer program including a processing procedure of an assembly model creation method according to the present embodiment, which will be described later, and data such as material properties acquired from various data servers 64 ₁ and 64 _2. Yes. Note that data such as material properties are used when the assembly model creation method according to the present embodiment is executed. Here, the storage unit 50m can be configured by a volatile memory such as a RAM (Random Access Memory), a nonvolatile memory, a hard disk device, or a combination thereof. The processing unit 50p can be configured by a memory and a CPU (Central Processing Unit). The storage unit 50m may be built in the processing unit 50p or may be in another device (for example, a database server). Thus, the assembly model creation device 50 may access the processing unit 50p and the storage unit 50m from the terminal device 60 by communication.

  The computer program can realize the processing procedure of the assembly model creation method according to the present embodiment by combining with the computer program already recorded in the model creation unit 51, the analysis unit 52, and the like included in the processing unit 50p. It may be. The assembly model creation apparatus 50 realizes the functions of the model creation unit 51, the analysis unit 52, and the condition determination unit 53 provided in the processing unit 50p by using dedicated hardware instead of the computer program. There may be.

  The assembly model creation method according to the present embodiment creates a tire model and an internal structure model that can be analyzed by a computer by creating an analysis model of the tire 1 and the internal structure 10 housed in the tire 1, A fitting model that can be analyzed by a computer is used to place the internal structure model inside the tire model. Next, the created mounting tool model is brought into contact with the structure model, and the mounting tool model is moved toward the inside of the tire model, thereby accommodating the internal structure model inside the tire model. Then, an assembly model is created by setting the procedure for releasing the contact between the wearing tool model and the internal structure model and the contact between the internal structure model and the tire model.

  FIG. 4-1 is a meridional cross-sectional view illustrating a relationship between the internal structure and the tire before the internal structure is disposed inside the tire. FIG. 4-2 is a meridional cross-sectional view illustrating an actual shape of the internal structure after the internal structure is disposed inside the tire. In creating the assembly model 100M, the deformation state of the internal structure 10 having a sound absorbing function arranged inside the tire 1 constituting the tire / internal structure assembly 100 shown in FIGS. 1 and 2 is reproduced. There is a need. Usually, the internal structure 10 is disposed inside the tire 1, contacts the inner surface of the tire 1, and rotates together with the tire 1. However, in the design stage, the internal structure 10 is not in the shape after being arranged inside the tire 1, so the shape and deformation state after the internal structure 10 is arranged in the tire 1 are based on the specifications in the design stage. Cannot be obtained.

  On the other hand, as shown in FIG. 4A, in the production of the assembly model 100M, the internal structure model 10M before being arranged inside the tire model 1M is a portion that interferes with the inner surface IW of the tire model 1M (FIG. 4). -1)). Therefore, as shown in FIG. 4B, when the internal structure model 10M is arranged inside the tire model 1M, the internal structure model 10M is deformed, and the internal structure model 10M interferes with the inner surface IW of the tire model 1M. Will not do. The method for creating an assembly model in the present embodiment creates an assembly model that can be analyzed by a computer by simulating the process in which the internal structure model 10M is deformed and stored in the tire model 1M. It is.

  FIG. 5 is a flowchart showing a procedure of a method for creating an assembly model according to the present embodiment. FIG. 6A is a perspective view showing the tire model, FIG. 6B is a perspective view showing the internal structure model, and FIG. 6C is a perspective view showing the wearing tool model. FIG. 7 is a schematic diagram showing a tire model and an internal structure model. FIG. 8 is a partial cross-sectional view showing a part of the meridional section of the tire / internal structure assembly model. FIG. 9-1 is a side view showing the wearing tool model, and FIG. 9-2 is a front view showing the wearing tool model. FIG. 10-1 is a meridional cross-sectional view illustrating the shape of the wearing tool model, and FIG. 10-2 is a perspective view illustrating the shape of the wearing tool model.

  In creating the assembly model 100M by the assembly model creation method according to the present embodiment, in step S101, the model creation unit 51 included in the processing unit 50p of the assembly model creation device 50 shown in FIG. Based on the coordinate data and physical property values input by 61, a tire model 1M shown in FIG. 6A, an internal structure model 10M shown in FIG. 6B, and a fitting model 15M shown in FIG. The tire model 1M, the internal structure model 10M, and the wearing tool model 15M are all analysis models that can be analyzed by a computer.

  The tire model 1M and the internal structure model 10M constituting the assembly model 100M are models used for performing rolling analysis, deformation analysis, and the like using a numerical analysis method such as a finite element method or a finite difference method. It is a model that can be analyzed by, and includes a mathematical model and a mathematical discretization model. In the present embodiment, a finite element method (FEM) is used as an analysis method used for rolling simulation or the like using the created assembly model 100M. The analysis method applicable to the assembly model creation method according to the present embodiment is not limited to the finite element method, and a boundary element method (BEM), a finite difference method (FDM), or the like is also used. it can. Further, the most appropriate analysis method can be selected according to the boundary condition or the like, or a plurality of analysis methods can be used in combination. Since the finite element method is an analysis method suitable for structural analysis, it can be suitably applied particularly to a structure such as a tire.

  The assembly model 100M is configured by arranging an internal structure model 10M inside a tire model 1M. The model creation unit 51 divides the tire into a plurality and a finite number of elements En composed of a plurality of nodes to create a tire model 1M shown in FIGS. 7 and 8, and the internal structure at a plurality of nodes. The internal structure model 10M shown in FIGS. 7 and 8 is created by dividing into a plurality of finite elements Em. As described above, in the present embodiment, the tire model 1M and the internal structure model 10M are prepared separately, and the internal structure is formed inside the tire model 1M using the mounting tool model 15M shown in FIG. 6-3. An assembly model 100M is created containing the model 10M.

  The assembly model 100M may further include a rim model, a wheel model, and an axle model. In this case, the rim model and the wheel model are assembled to the tire model 1M constituting the assembly model 100M. The axle model is attached to the wheel model. In the present embodiment, rolling analysis or the like is performed using the assembly model 100M, and therefore the assembly model 100M and the tire model 1M and the internal structure model 10M constituting the assembly model 100M have a three-dimensional shape.

  The elements of the tire model 1M and the internal structure model 10M constituting the assembly model 100M include solid elements such as a quadrilateral element in a two-dimensional plane, a tetrahedral solid element, a pentahedral solid element, a hexahedral solid element in a three-dimensional body, for example. It is desirable to use an element that can be used by a computer, such as a shell element such as an element, a triangular shell element, or a quadrangular shell element, or a surface element. In the process of analysis, the elements thus divided are identified one by one by the model creation unit 51 using the three-dimensional coordinates in the three-dimensional model.

  The mounting tool model 15M shown in FIG. 6-3 is not used when the actual internal structure 10 is housed in the actual tire 1, but is used only in creating an assembly model using a computer. It is a virtual tool model inside. The wearing tool model 15M is, for example, an analysis model including a plurality of finite elements including a plurality of nodes, and a continuum element or a shell element can be used. The wearing tool model 15M may be configured using an analytical rigid surface or a discrete rigid surface element.

  As shown in FIGS. 6-3 and 9-1, the mounting tool model 15M has an annular shape and is composed of two or more parts in the circumferential direction (the direction indicated by the arrow C in FIG. 9-1). It is preferable. Further, as illustrated in FIG. 9B, the wearing tool model 15M includes two or more portions in the axial direction of the wearing tool model 15M (direction parallel to the Y axis that is the rotation axis of the tire model 1M). It is preferable. This is because the fitting model 15M is moved radially inward of the tire model 1M from the inner surface IW of the tire model 1M when the internal structure model 10M is accommodated in the tire model 1M.

  The wearing tool model 15M is composed of two or more parts in the circumferential direction, and by comprising two or more parts in parallel with the axial direction, the wearing tool model 15M is arranged in its radial direction (FIG. 9-1). It can be moved in the direction of arrow D) and in the direction parallel to the axial direction (direction of arrow A in FIG. 9-2). In addition, it is preferable that the wearing tool model 15M includes two or more portions in at least one of the circumferential direction and the direction parallel to the axial direction.

  As shown in FIGS. 10-1 and 10-2, the mounting tool model 15M having an annular shape is at least part of the inner surface IW of the tire 1 shown in FIG. 1 or the tire model 1M shown in FIG. 10-1. It is preferable to convert the shape into an analytical model. That is, the shape of the wearing tool model 15M is the shape of the inner surface IW within a predetermined range such as the tire 1 shown in FIG. 1 or the tire model 1M shown in FIG. 10-1. As a result, the internal structure model 10M can be reliably stored inside the tire model 1M.

  The inner surface IW as the fitting model 15M extends from the center CL in the width direction of the tire model 1M to the maximum cross-sectional width W of the inner surface IW of the tire model 1M and the like in the meridional section of the tire model 1M and the like. And a range up to a predetermined length (for example, a length corresponding to a range of 30 degrees to 120 degrees in the central angle). The shape of the inner surface IW of the tire model 1M or the like in this range is a part of the wearing tool model 15M. Then, a part of the wearing tool model 15M obtained in this way is combined in a plurality and in a ring shape to obtain the wearing tool model 15M.

  A virtual surface parallel to the inner surface IW of the tire model 1M or the like at a position slightly inside the inner surface IW of the tire model 1M or the like may be a part of the wearing tool model 15M. Further, as shown in FIG. 9B, the wearing tool model 15M is arranged so that the annular models face each other. When creating the wearing tool model 15M, one model of the wearing tool model 15M may be created, and this may be copied symmetrically to create the other model.

  FIG. 11 is a meridional sectional view showing initial positions of the tire model, the internal structure model, and the wearing tool model in the method for creating the assembly model according to the present embodiment. FIG. 12 is a meridional sectional view showing a state in which the internal structure model is housed in the tire model. FIG. 13 is a meridional sectional view showing a state in which the internal structure model is housed in the tire model and the wearing tool is released. When the tire model 1M, the internal structure model 10M, and the wearing tool model 15M are created, the model creation unit 51 stores them in the storage unit 50m. Next, it progresses to step S102. In step S102, the model creation unit 51 places the tire model 1M, the internal structure model 10M, and the wearing tool model 15M at predetermined initial positions.

  As shown in FIG. 11, before the internal structure model 10M is accommodated in the tire model 1M, the internal structure model 10M is disposed inside the tire model 1M. This position is the initial position of the internal structure model 10M. At this time, interaction such as contact is not defined between the internal structure model 10M and the tire model 1M, and there may be a portion that interferes between the internal structure model 10M and the tire model 1M. The wearing tool model 15M is disposed at a position where it does not interfere with the internal structure model 10M at the initial position. In this case, the wearing tool model 15M may be modeled at a position that does not interfere with the internal structure model 10M at the initial position.

  The model creation unit 51 reads the tire model 1M, the internal structure model 10M, and the wearing tool model 15M created in step S101 from the storage unit 50m. The model creation unit 51 reads the initial position of the tire model 1M and the like input from the input / output device 61 or the initial position of the tire model 1M and the like stored in advance in the storage unit 50m, and the tire model 1M and the internal structure The model 10M and the wearing tool model 15M are respectively arranged at predetermined initial positions. The model creation unit 51 associates the relationship between the tire model 1M, the internal structure model 10M, the wearing tool model 15M, and the respective initial positions, and stores them in the storage unit 50m.

  Next, in step S103, the model creation unit 51 stores the internal structure model 10M in the tire model 1M. Specifically, the model creation unit 51 defines contact between the wearing tool model 15M and the internal structure model 10M, and moves the wearing tool model 15M toward the inside of the tire model 1M (in the direction of arrow R in FIG. 11). Move. Then, the wearing tool model 15M starts moving from a position where it does not interfere with the internal structure model 10M. The model creation unit 51 moves the wearing tool model 15M to the same position as the inner surface IW of the tire model 1M or the inner side of the tire model 1M from the inner surface IW of the tire model 1M. As a result, the internal structure model 10M can be accommodated in the tire model 1M. At this time, as shown in FIG. 12, the internal structure model 10M is housed inside the tire model 1M together with the mounting tool model 15M in a deformed state.

  When the internal structure model 10M is stored inside the tire model 1M, the process proceeds to step S104, and the model creation unit 51 releases the wearing tool model. Specifically, the model creation unit 51 releases the contact between the wearing tool model 15M and the internal structure model 10M. For example, the model creating unit 51 deletes the wearing tool model 15M or prevents an interaction (for example, force interaction) between the wearing tool model 15M and the internal structure model 10M. .

  Next, it progresses to step S105 and the model preparation part 51 sets interaction with the tire model 1M and the internal structure model 10M. Specifically, the contact between the tire model 1M and the internal structure model 10M is defined. As a result, as shown in FIG. 13, the internal structure model 10M is housed inside the tire model 1M, and the internal structure model 10M deforms in contact with the inner surface IW of the tire model 1M. 100M is completed. Note that when the internal structure model 10M comes into contact with the inner surface IW of the tire model 1M, strain and stress are also generated in the tire model 1M.

  When the assembly model 100M is completed, the process proceeds to step S106, where the model creation unit 51 acquires information on the assembly model 100M and stores it in a predetermined storage area of the storage unit 50m. The information of the assembly model 100M includes, for example, displacements from the initial positions of the tire model 1M and the internal structure model 10M, and physical quantities such as contact force, stress, and strain between the tire model 1M and the internal structure model 10M. It is.

  As described above, according to the method for creating an assembly model according to the present embodiment, the internal structure model 10M is deformed inside the tire model 1M by the mounting tool model 15M. And stress is generated. As a result, the method for creating the assembly model according to the present embodiment allows the state of deformation of the internal structure 10 when the internal structure 10 is actually housed in the tire 1, for example, the strain of the internal structure 10 or the like. Since the stress state can be reproduced, the actual state in which the internal structure 10 is housed in the tire 1 can be reproduced.

  When the assembly model 100M is created, the analysis unit 52 included in the processing unit 50p of the assembly model creation apparatus 50 uses the created assembly model 100M to perform dynamic analysis or static analysis represented by rolling analysis, or Perform eigenvalue analysis, frequency response analysis, heat conduction analysis, etc. Then, based on the analysis result, the performance of the tire / internal structure assembly 100, the tire 1, or the internal structure 10 which is the basis of the created assembly model 100M is evaluated.

  As described above, the assembly model creation method and the assembly model creation computer program according to the present invention include a tire / internal structure in which an internal structure having a sound absorbing function is accommodated in a tire in a simulation using a computer. It is suitable for creating an analysis model of a structure assembly.

It is sectional drawing which shows the meridional section which passes along the rotating shaft of a tire / internal structure assembly. It is a schematic diagram which shows the example which has arrange | positioned the internal structure inside the tire. It is explanatory drawing which shows the structure of the preparation method of the assembly model which concerns on this embodiment. It is meridional sectional drawing which shows the relationship between an internal structure and a tire before arrange | positioning an internal structure inside a tire. It is meridional sectional drawing which shows the actual shape of an internal structure after arrange | positioning an internal structure inside a tire. It is a flowchart which shows the procedure of the preparation method of the assembly model which concerns on this embodiment. It is a perspective view which shows a tire model. It is a perspective view which shows an internal structure model. It is a perspective view which shows a mounting tool model. It is a schematic diagram which shows a tire model and an internal structure model. It is a fragmentary sectional view which shows a part of meridional section of a tire / internal structure assembly model. It is a side view which shows a mounting tool model. It is a front view which shows a mounting tool model. It is meridional sectional drawing which shows the shape of a mounting tool model. It is a perspective view which shows the shape of a mounting tool model. FIG. 6 is a meridional cross-sectional view showing initial positions of a tire model, an internal structure model, and a mounting tool model in the method for creating an assembly model according to the present embodiment. It is meridional sectional drawing which shows the state which accommodated the internal structure model inside the tire model. It is meridional sectional drawing which shows the state which accommodated the internal structure model inside the tire model, and released | released the wearing tool.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tire 1M Tire model 10 Internal structure 10M Internal structure model 15M Wearing tool model 50 Assembly model creation apparatus (assembly model creation apparatus)
50m storage unit 50p processing unit 51 model creation unit 52 analysis unit 59 input / output unit 60 terminal device 61 input / output device 62 display device 100 tire / internal structure assembly 100M assembly model

Claims (6)

A tire model and an internal structure model that can be analyzed by a computer by creating an analysis model of the tire and the internal structure housed in the tire, and creating the internal structure model inside the tire model The procedure to create a wearable model that can be analyzed by computer,
Placing the internal structure model in the tire model by contacting the mounting tool model with the internal structure model and moving the mounting tool model toward the inside of the tire model;
A procedure for releasing contact between the wearing tool model and the internal structure model;
A procedure for setting contact between the internal structure model and the tire model;
A method for creating an assembly model, comprising:   The shape of the wearing tool model is an annular shape, and at least one of a circumferential direction of the wearing tool model and an axial direction of the wearing tool model includes two or more portions. 2. A method for creating an assembly model according to 1.   The method of creating an assembly model according to claim 2, wherein the mounting tool model moves in at least one of an axial direction and a radial direction.   The method for creating an assembly model according to claim 2 or 3, wherein a part of the wearing tool model is an analytical model of a shape of at least a part of the tire model or an inner surface of the tire. In the procedure for accommodating the internal structure model inside the tire model,
5. The method of creating an assembly model according to claim 1, wherein the mounting tool model starts moving from a position that does not interfere with the internal structure model. 6.   A computer program for creating an assembly model, which causes a computer to execute the assembly model creation method according to any one of claims 1 to 5.

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