JP7375590B2 - Vehicle body manufacturing method and vehicle body structure - Google Patents

Description

The present invention relates to a method of manufacturing a vehicle body using a vehicle body member having a flange portion, and a vehicle body structure.

A body of a vehicle such as an automobile has a portion formed by joining one body member to another body member having a flange portion. Furthermore, a technique is known in which a vibration damping member is attached to the joint portion to damp vibration. The vibration damping member may be used in the form of an adhesive for bonding vehicle body members together. FIG. 9 of Patent Document 1 discloses a method of applying a vibration damping member made of an adhesive along the edge of the flange portion. As the vibration damping member, a thermosetting material is used exclusively. After the application of the vibration damping member, the vibration damping member is cured by providing an appropriate heat curing step.

JP2019-38364A

In the vehicle body structure of Patent Document 1, the assembled vehicle body structure is transferred to the processing zone for the thermosetting step with the vibration damping member exposed at the edge of the flange portion. During this transfer, there is a risk that other members may come into contact with the applied portion of the vibration damping member and be damaged. In addition, other processing steps such as a cleaning step may have to be performed during the heat curing step, and there is a risk that the applied portion of the vibration damping member will not be able to maintain its original applied shape due to execution of the other processing steps. be. In these cases, a problem may occur in which the vibration damping member cannot exhibit the desired damping effect.

An object of the present invention is to provide a vehicle body manufacturing method and a vehicle body structure in which a vibration damping member is attached to a joint portion between one vehicle body member and another vehicle body member having a flange portion, in which the vibration damping member The objective is to ensure that the damping effect is achieved.

A method for manufacturing a vehicle body according to one aspect of the present invention is a method for manufacturing a vehicle body using a first vehicle body member and a second vehicle body member having a flange portion, the method comprising: the first vehicle body member and the second vehicle body member having a flange portion. a polymerization step of overlapping the flange portion of the second vehicle body member, and applying a thermosetting vibration damping member to the edge of the flange portion so as to adhere to the first vehicle body member and the flange portion; a coating step, a temporary curing step of temporarily curing the applied vibration damping member, a main curing step of main curing the temporarily hardened vibration damping member by heat, and a temporary curing step and the main curing step. The present invention is characterized in that it includes another processing step performed on the first vehicle body member and the second vehicle body member in between .

According to this vehicle body manufacturing method, before the main curing process, a temporary curing process is performed in which the vibration damping member applied in the coating process is temporarily hardened. Therefore, even if the vibration damping member is applied in such a manner that it is exposed to the outside at the edge of the flange portion, the applied vibration damping member can maintain its original applied shape through temporary curing. Therefore, it is possible to manufacture a vehicle body in which the vibration damping member can exhibit the desired damping effect.

In the method for manufacturing a vehicle body described above, another treatment step for the first vehicle body member and the second vehicle body member may be performed between the temporary hardening step and the main hardening step.

In this car body manufacturing method, even if another treatment process such as a cleaning process is preceded to the main curing process, the temporary curing process has already been carried out, so the shape of the applied vibration damping member changes. will not occur.

In the method for manufacturing a vehicle body described above, it is preferable that the temporary curing step is a step of temporarily curing the vibration damping member by applying heat to the vibration damping member.

According to this method of manufacturing a vehicle body, a thermosetting vibration damping member can be quickly temporarily cured. Examples of methods for applying heat to the vibration damping member include heating from the outside by blowing hot air, heating from the inside by electromagnetic induction heating, and the like.

In the above method for manufacturing a vehicle body, the vibration damping member is a material that can be cured by irradiation with light, and the temporary curing step is a step of irradiating the vibration damping member with light to temporarily harden it. This is desirable.

According to this method of manufacturing a vehicle body, the vibration damping member can be quickly temporarily cured by irradiation with light. A specific example is a mode in which a vibration damping member made of a thermosetting material containing an ultraviolet curing agent is used and the vibration damping member is irradiated with ultraviolet rays to temporarily cure the vibration damping member.

In the method for manufacturing a vehicle body described above, the application step may be a step of applying the vibration damping member so that the vibration damping member is present on a part of the edge of the flange portion.

According to this method of manufacturing a vehicle body, the vibration damping member is not continuously applied along the edge of the flange portion, but an unrestricted portion where the vibration damping member is not applied is formed at the edge of the flange portion. Thereby, the flange portions of the first vehicle body member and the second vehicle body member are not restrained unnecessarily, and vibration energy can be concentrated on the applied portion of the vibration damping member, thereby making it possible to enhance the vibration damping effect.

In this case, it is preferable that the application step is a step of applying the vibration damping member so that the vibration damping member is scattered at an edge of the flange portion.

According to this method of manufacturing a vehicle body, it is possible to manufacture a vehicle body that exhibits the maximum vibration damping effect using a small amount of vibration damping members.

The method for manufacturing a vehicle body described above may further include, after the polymerization step, a welding step of spot welding the first vehicle body member and the flange portion.

According to this method of manufacturing a vehicle body, vibrations can be damped by providing a vibration damping member at the joint between the first vehicle body member and the flange portion, which are rigidly connected by spot welding.

A vehicle body structure according to another aspect of the present invention includes: a first vehicle body member; a second vehicle body member having a flange portion serving as a joint portion to the first vehicle body member; The present invention is characterized by comprising thermosetting vibration damping members capable of temporary curing and permanent curing by heat, which are arranged in a dotted manner so as to adhere to one vehicle body member and the flange portion.

According to this vehicle body structure, the vibration damping effect can be enhanced by concentrating vibration energy on the vibration damping members scattered at the edge of the flange portion.

In the vehicle body structure described above, the vibration damping member is scattered at one end and the other end in the flange width direction, when the direction along the edge of the flange portion of the second vehicle body member is defined as the flange width direction. It may also be configured as follows.

Generally, one end and the other end of the flange in the width direction are parts that are likely to swing when vibration is applied. By disposing vibration damping members in these parts in a scattered manner, the vibration damping effect can be further enhanced.

In the vehicle body structure described above, the vibration damping members may be scattered at positions spaced apart from one end and the other end in the width direction of the flange by a predetermined distance toward the center.

According to this vehicle body structure, the interval between the vibration damping member on one end side and the vibration damping member on the other end side in the flange width direction can be configured not to be too wide. Therefore, lifting of the flange portion in the central region in the width direction of the flange can be suppressed.

In the vehicle body structure described above, the vibration damping member may be disposed intermittently from one end to the other end in the width direction of the flange.

According to this vehicle body structure, the vibration damping effect can be further enhanced by identifying, for example, a location in the flange portion that is likely to swing, and disposing a vibration damping member intermittently at the location.

According to the present invention, in a case where a vibration damping member is attached to a joint portion between a first vehicle body member and a second vehicle body member having a flange portion, the vibration damping member can reliably exhibit a desired damping effect in a vehicle. It is possible to provide a car body manufacturing method and a car body structure.

FIG. 1 is a schematic side view of a vehicle body to which the present invention is applied. FIG. 2 is a schematic bottom view of a vehicle body to which the present invention is applied. FIG. 3 is a perspective view of a vehicle body structure that constitutes a frame having a closed cross section in the vehicle body. FIG. 4 is an exploded perspective view of the vehicle body structure shown in FIG. 3. FIG. 5(A) is a perspective view showing an example of a flange joint between a flat plate member and a reinforcing member, and FIG. 5(B) is a sectional view of the flange joint. FIG. 6(A) is a perspective view showing another example of a flange joint between a flat plate member and a reinforcing member, and FIG. 6(B) is a sectional view of the flange joint. FIG. 7 is a process chart showing the procedure of the vehicle body manufacturing method according to the embodiment of the present invention. FIGS. 8(A) to 8(C) are schematic diagrams for explaining each step of the vehicle body manufacturing method. FIGS. 9(A) and 9(B) are schematic diagrams for explaining a temporary curing step using heat in the vehicle body manufacturing method. FIG. 10 is a schematic diagram for explaining a temporary curing step by light irradiation in the vehicle body manufacturing method. FIG. 11 is a graph showing the amount of vibration reduction by the damping adhesive. FIG. 12 is a graph showing the amount of vibration reduction by the damping adhesive. FIG. 13 is a perspective view showing an example of a case where the damping adhesive is arranged in a scattered manner on the edge of the flange portion. FIG. 14 is a perspective view showing an example of the case where the damping adhesive is arranged in a scattered manner on the edge of the flange portion. FIG. 15 is a perspective view showing an example of a case where the damping adhesive is arranged in a scattered manner on the edge of the flange portion. FIG. 16 is a perspective view showing an example of a case where the damping adhesive is arranged in a scattered manner on the edge of the flange portion. FIG. 17 is a graph showing the amount of vibration reduction by the damping adhesive. FIG. 18 is a graph showing the amount of vibration reduction by the damping adhesive.

[Vehicle structure]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing a vehicle body and a vehicle body structure according to the present invention will be described in detail with reference to the drawings. First, the overall body structure of a vehicle to which the present invention is applied will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic side view of a vehicle body 1 of the vehicle, and FIG. 2 is a bottom view thereof. The vehicle body 1 illustrated in FIGS. 1 and 2 is a hatchback type four-wheel vehicle. Vehicles to which the present invention is applied are not limited to those illustrated here, and may be other types of four-wheeled vehicles, trucks, buses, various work vehicles, and the like.

The vehicle body 1 includes side frames 10 that constitute left and right side surfaces of the vehicle. As shown in FIG. 1, the side frame 10 includes a roof rail 11, a front pillar 12, a center pillar 13, a rear pillar 14, and a side sill 15. These constituent members of the side frame 10 are constituted by highly rigid frame members having a closed cross section. The roof rail 11 extends in the upper part of the vehicle, and the side sill 15 extends in the lower part of the vehicle in the longitudinal direction of the vehicle. The roof rail 11 and the side sills 15 are arranged as a pair on the left and right sides of the vehicle. The roof rail 11 and the side sill 15 are vertically connected to each other by a front pillar 12 on the front side, a rear pillar 14 on the rear side, and a center pillar 13 near the center in the longitudinal direction.

As shown in FIG. 2, a tunnel rain 16 extends in the front-rear direction in a central region in the vehicle width direction between the pair of side sills 15. A plurality of cross members 17 are arranged to cross the tunnel rain 16. Both ends of these cross members 17 are connected to left and right side sills 15, respectively. This cross member 17 is also made of a highly rigid frame member having a closed cross section. A flat floor panel 18 is disposed between the pair of side sills 15 and below the cross member 17. These floor panels 18, side sills 15, tunnel reins 16, and cross members 17 are interconnected to form a lower structure of the vehicle. Note that a roof rain (not shown) is constructed between the pair of roof rails 11.

[Vehicle body structure with closed cross section]
FIG. 3 is a perspective view of a vehicle body structure 2 that constitutes a frame having a closed cross section C in the vehicle body 1, and FIG. 4 is an exploded perspective view of the vehicle body structure 2. The vehicle body structure 2 includes a flat plate member 3 (first vehicle body member), a hat-shaped member 4, and a reinforcing member 5 (second vehicle body member). The vehicle body structure 2 illustrated here is a simplified representation of the structure of the roof rail 11, front pillar 12, center pillar 13, rear pillar 14, side sill 15, and cross member 17, each having a closed cross-section as described above. be. For example, in the case of the cross member 17, the floor panel 18 is attached to the flat plate member 3 in FIG. The rigid reinforcing bodies arranged correspond to the reinforcing members 5, respectively.

The flat member 3 is a flat member having a width equal to or greater than that of the hat-shaped member 4. Hat-shaped member 4 includes a hat main body portion 41 and a flange portion 42. The hat main body 41 includes a top plate 411 made of a flat plate, and a pair of side plates 412 extending from both side edges of the top plate 411, respectively. 3 and 4 show an example in which the top plate 411 extends horizontally and the side plates 412 extend vertically downward from the side edges of the top plate 411. The flange portion 42 is a thin strip-shaped flat plate portion formed by bending the lower edges of the pair of side plates 412 outward at a right angle.

The flange portion 42 becomes a joint portion to the flat plate member 3. The flange portion 42 is overlapped on the flat plate member 3 and joined to form a flange joint portion F1. That is, in the portion where the flange portion 42 and the flat plate member 3 overlap, a plurality of spot joint portions SW, in which the two are welded in a dotted manner, are formed at predetermined intervals. By integrating the flat plate member 3 and the hat-shaped member 4 at such a flange joint portion F1, a vehicle body structure 2 having a closed cross-section portion C having a rectangular cross-section is formed.

The reinforcing member 5 is a reinforcing member disposed within the closed cross section C to maintain the shape of the closed cross section C. In other words, the reinforcing member 5 acts on the deformation force that causes the top plate 411 and the flat plate member 3 in the vehicle body structure 2 to approach each other or the side plates 412 to approach each other, which causes the hat-shaped member 4 to be crushed, or to twist the hat-shaped member 4. It serves to increase resistance to deforming forces. The reinforcing member 5 is also called a joint member, and is formed by punching or bending a plate material having excellent rigidity, such as a steel material.

The reinforcing member 5 is formed by a base plate 51 made of a flat plate having a rectangular shape corresponding to the cross-sectional shape of the closed cross-section portion C, and by bending the lower side, the upper side, and a pair of side sides of the base plate 51 at approximately right angles. It includes a lower flange portion 52A, an upper flange portion 52B, and a pair of horizontal flange portions 52C. The base plate 51 has a surface that is generally perpendicular to the longitudinal direction of the vehicle body structure 2, which is the direction in which the closed cross-section portion C extends, and serves to receive the deformation force applied to the vehicle body structure 2. Note that an opening may be provided in the base plate 51 so that the inside of the closed section C is not completely partitioned in the longitudinal direction.

The lower flange portion 52A is joined to the flat plate member 3 to form a flange joint portion F21. The pair of horizontal flanges 52C are respectively joined to the pair of side plates 412 of the hat-shaped member 4, forming flange joints F22 and F23. The upper flange portion 52B is joined to the top plate 411 of the hat-shaped member 4, forming a flange joint portion F24. These flange joints F21 to F24 are joined together by spot joints SW.

In FIG. 3, among the flange joint parts F21 to F24, the flange joint part F21 of the lower flange part 52A shows an example in which a damping adhesive 6 (vibration damping member) is attached. The damping adhesive 6 is a member arranged to reduce vibrations applied to the vehicle body structure 2. In the flange joint part F21, even if the overlapping lower flange part 52A and the flat plate member 3 are joined together using the spot joint part SW and the damping adhesive 6 (hereinafter referred to as well bond joint), the damping adhesive is not applied. The material 6 may be joined (hereinafter referred to as overlapping joining) by only the material 6.

[Details of flange joint]
Next, the flange joint F21 to which the damping adhesive 6 is attached will be described in detail. The damping adhesive 6 is not particularly limited as long as it is a thermosetting material and has adhesive properties and a predetermined viscoelasticity. For example, a viscoelastic material made of a silicone material or an acrylic material may be used. can do. The physical properties of the damping adhesive 6 after curing are such that the storage modulus is within the range of 200 MPa to 3000 MPa, and the loss coefficient is 0.02 MPa under the conditions that the temperature is 20° C. and the frequency of the excitation force is 200 Hz. Those having two or more characteristics are preferred. Such a damping adhesive 6 absorbs vibration energy as strain energy, converts it into thermal energy, and dissipates it, thereby damping vibrations.

FIG. 5(A) is an enlarged perspective view of the flange joint portion F21, and FIG. 5(B) is a cross-sectional view of the flange joint portion F21. The lower flange portion 52A includes a root side edge 521 and a tip side edge 522. The root side edge 521 is an edge located at a bending point of the lower flange portion 52A with respect to the base plate 51, and is a portion continuous to the lower end of the base plate 51. The tip side edge 522 is an edge located at the tip of the lower flange portion 52A in the bending direction. That is, in the present invention, "the edge of the flange portion" means either the root side edge 521 or the tip side edge 522.

The lower flange portion 52A is directly overlapped with the flat plate member 3. In other words, the lower surface of the lower flange portion 52A is in contact with the upper surface of the flat plate member 3. That is, the damping adhesive 6 is not actively interposed between the lower flange portion 52A and the flat plate member 3. The damping adhesive 6 is continuously applied along the root side edge 521 of the lower flange portion 52A over the entire length of the lower flange portion 52A in the width direction (direction along the bending line of the lower flange portion 52A). There is. As shown in FIG. 5(B), the damping adhesive 6 is bonded to both the flat plate member 3 and the lower flange portion 52A at the root side edge 521.

FIG. 6(A) is an enlarged perspective view of a flange joint F21 according to another embodiment, and FIG. 6(B) is a cross-sectional view of the flange joint F21. The difference from the embodiment of FIGS. 5A and 5B is that the damping adhesive 6 is disposed on the tip end edge 522 of the lower flange portion 52A. The damping adhesive 6 is continuously applied along the tip end edge 522 over the entire length of the lower flange portion 52A in the width direction. Further, the damping adhesive 6 is bonded to both the flat plate member 3 and the lower flange portion 52A at the tip end edge 522.

[Flow of body manufacturing]
Next, a method for manufacturing the vehicle body 1 including the above-described vehicle body structure 2 will be described. A characteristic feature of the manufacturing method of this embodiment is that it includes a step of temporarily curing the applied damping adhesive 6 after applying the damping adhesive 6 to the required locations and before proceeding to the next step. be. Therefore, as the damping adhesive 6, a thermosetting damping adhesive 6 is used which can be temporarily cured by some means and can be permanently cured by heat.

FIG. 7 is a process chart showing the procedure of the vehicle body manufacturing method according to the embodiment of the present invention. First, a superposition step is performed in which vehicle body members to be joined are overlapped (step M1). In the case of the vehicle body structure 2, the flange portion 42 of the hat-shaped member 4 is aligned and overlapped at a predetermined position of the flat plate member 3. Further, the flange joint portions F21 to F24 of the reinforcing member 5 are also overlapped at predetermined positions of the flat plate member 3 and the hat-shaped member 4.

FIG. 8(A) is a diagram showing the execution status of step M1 in the flange joint F21 to which the damping adhesive 6 is attached. The lower flange portion 52A of the reinforcing member 5 (second vehicle body member) has a flange lower surface 52F that faces the upper surface 3F of the flat plate member 3 (first vehicle body member). The upper surface 3F and the flange lower surface 52F are flat surfaces. In the superposition step M1, the lower flange portion 52A is superimposed on the flat plate member 3 such that the flange lower surface 52F contacts the upper surface 3F at a predetermined position of the flat plate member 3.

Subsequently, a joining step is performed to join the overlapping vehicle body members to each other (step M2). Although there is no limitation on the form of the joining process M2, a preferred form is a welding process using spot welding. FIG. 8(B) shows the execution status of the joining process M2 at the flange joint part F21. Spot welding is performed by arranging a welding electrode at a predetermined position of the overlapped portion of the lower flange portion 52A and the flat plate member 3, and a spot joint SW is formed at the overlapped portion. This joining step M2 is a step performed when the flange joining portion F21 is well bonded. When the flange joint portion F21 is an overlap joint, the joining step M2 is skipped.

Thereafter, a coating step is performed in which a thermosetting damping adhesive 6 is applied to required locations (step M3). FIG. 8C shows the execution status of the coating process M3 at the flange joint F21. Here, as illustrated in FIG. 6, an example is shown in which the damping adhesive 6 is applied along the tip end edge 522 of the lower flange portion 52A. Of course, as illustrated in FIG. 5, the damping adhesive 6 may be applied along the root side edge 521. If desired, a damping adhesive 6 may be applied along both the proximal edge 521 and the distal edge 522.

In FIG. 8C, a coating machine 61 including a nozzle that discharges the damping adhesive 6 is schematically shown as an example of performing the coating process. The damping adhesive 6 is made of a thermosetting material and has fluidity that allows it to be extruded from the nozzle during the coating process. As described above, the damping adhesive 6 is applied so as to adhere to both the upper surface 3F of the flat plate member 3 and the tip end edge 522 of the lower flange portion 52A. The nozzle is positioned to perform such application, and the nozzle is moved along the direction in which the distal end edge 522 extends while discharging the damping adhesive 6. Incidentally, the damping adhesive 6 may be similarly applied to the overlapped portion of the flange portion 42 of the hat-shaped member 4 and the flat plate member 3.

Next, a temporary curing step M4 is performed in which the applied damping adhesive 6 is temporarily hardened. Since the damping adhesive 6 is a thermosetting material, it is not yet solidified at the stage where the coating process M3 is completed. Moreover, the damping adhesive 6 is not arranged so as to be sandwiched between the flat plate member 3 and the lower flange portion 52A, but is arranged adjacent to the side of the tip end edge 522 and exposed. . In this state, if the vehicle body 1 is transferred to a processing zone where the damping adhesive 6 is thermally cured, there is a risk that other members may come into contact with the applied portion of the damping adhesive 6 and be damaged. Further, due to the convenience of the vehicle manufacturing process, other processing steps (in this embodiment, steps M5 and M6, which will be described later) may have to be performed before the thermosetting step. In this case, the damping adhesive 6 in an uncured state may be damaged by contact with the damping adhesive 6 from processing equipment, etc. during the execution of the other processing steps, vibrations during processing, collision of sprayed objects, etc. There is a possibility that the shape may not be maintained. In view of this point, a temporary curing process M4 is performed after the coating process M3, in which the applied damping adhesive 6 is cured to such an extent that the applied shape can be maintained.

The temporary curing step M4 can be a step of applying heat to the applied damping adhesive 6 to temporarily harden it. FIGS. 9A and 9B are schematic diagrams for explaining the thermal temporary curing step M4. FIG. 9A shows an example in which the damping adhesive 6 is temporarily cured by blowing hot air HA onto the damping adhesive 6. Hot air HA generated by the hot air generator 62 is introduced into the closed section C from the opening 2A of the vehicle body structure 2. The introduced hot air HA blows against the damping adhesive 6. As a result, the damping adhesive 6 is temporarily cured. In addition, in this embodiment, a ventilation opening is provided in the base plate 51 of the reinforcement member 5 on the front stage side so that the hot air HA can easily be blown onto the reinforcement member 5 on the rear stage side (the side far from the hot air generator 62). is desirable.

FIG. 9B shows an example in which the damping adhesive 6 is temporarily cured by electromagnetic induction heating. In this embodiment, a heating device including an IH heating head 64 having an IH coil 63 and an IH power source 65 that supplies high frequency power to the IH coil 63 is used. The IH heating head 64 is positioned relative to the vehicle body structure 2 so that the magnetic flux φ generated by the IH coil 63 passes through the joint between the flat plate member 3 and the reinforcing member 5. The damping adhesive 6 is temporarily cured by the Joule heat accompanying the induced current induced in the joint portion. According to the above-described temporary curing step M4 of applying heat to the damping adhesive 6, the damping adhesive 6 can be quickly temporarily cured by utilizing the inherent property of being a thermosetting type.

The temporary curing step M4 may be a step of irradiating the applied damping adhesive 6 with light to temporarily harden it. FIG. 10 is a schematic diagram for explaining a temporary curing step M4 by irradiation with UV light (ultraviolet light) OP. In this embodiment, a UV light generation device including a UV light irradiation head 66 and a UV light source 67 that generates UV light OP is used. UV light OP generated by the UV light source 67 is sent to the UV light irradiation head 66 through an optical fiber bundle or the like, and is irradiated onto the attenuating adhesive material 6 .

In the embodiment of FIG. 10, a damping adhesive 6 made of a material that can be cured not only by heat but also by irradiation with light is used. For example, the damping adhesive 6 made of an acrylic resin that undergoes radical photopolymerization or an epoxy resin that undergoes cationic photopolymerization can be used. According to this embodiment, there is an advantage that the attenuation adhesive material 6 can be rapidly temporarily cured by irradiation with the UV light OP.

Returning to FIG. 7, after the temporary curing step M4, a cleaning step M5 of the vehicle body structure 2 and a rust preventive electrodeposition coating step M6 are sequentially performed. These steps M5 and M6 correspond to other processing steps performed between the temporary curing step M4 described above and the step of actually curing the damping adhesive 6 (step M7 to be described later). Even if such other processing steps are performed, the applied shape will not change because the damping adhesive 6 has already been temporarily cured.

The cleaning step M5 is a step of cleaning the surface of the vehicle body structure 2 to be coated with a rust preventive agent. A predetermined cleaning liquid is sprayed onto the surfaces of the flat plate member 3, hat-shaped member 4, and reinforcing member 5. At this time, the cleaning liquid is also sprayed onto the damping adhesive 6 applied to the lower flange portion 52A. If the damping adhesive 6 has not been temporarily cured, the damping adhesive 6 may be scattered due to the blowing of the cleaning liquid. However, in this embodiment, since the damping adhesive 6 has already been temporarily cured, scattering of the damping adhesive 6 and deformation of the applied shape can be suppressed.

The electrodeposition coating process M6 is a process in which the vehicle body structure 2 is immersed in an electrodeposition liquid containing a rust preventive agent. Specifically, the car body structure 2 and an electrode are placed in a tank filled with the electrodeposition liquid, and by generating a potential difference between the two, a rust preventive layer is deposited on the surface of the car body structure 2. let

After that, a coating drying step M7 is executed. The paint drying process M7 is a process in which the vehicle body structure 2 having the rust preventive layer coated in the process M6 is heated and dried at a predetermined temperature for a certain period of time. In this embodiment, this coating drying step M7 also serves as a main curing step in which the damping adhesive 6 is main hardened by heat. That is, the heat applied to the vehicle body structure 2 for drying the rust preventive layer is utilized as heat for permanently curing the damping adhesive 6. This makes it possible to reduce the number of heat treatment steps in manufacturing the vehicle body, thereby increasing manufacturing efficiency. Conversely, as a result of utilizing the coating drying process M7 for the main curing process of the damping adhesive 6, the applied damping adhesive 6 will be exposed to the cleaning process M5 and the electrodeposition coating process M6, resulting in a change in the applied shape. Problems such as deformation may occur. However, in this embodiment, since the damping adhesive 6 is temporarily cured in advance, the above problem can be avoided.

[Vibration damping effect of damping adhesive]
11 and 12 are graphs showing the amount of vibration reduction caused by the damping adhesive 6 attached to the lower flange portion 52A of the reinforcing member 5. FIG. FIG. 11 shows the amount of vibration reduction in the case of well bond bonding in which spot bonding portion SW is also used. The horizontal axis of the graph is the storage modulus [MPa] of the test material. The vertical axis of the graph indicates the strain energy sharing ratio, which indicates how much strain energy was shared by the test material during cross-sectional deformation of the vehicle body structure 2. The strain energy sharing rate [%] is an index indicating the amount of vibration reduction by the damping adhesive 6, and the higher the sharing rate, the greater the vibration reduction amount (excellent vibration damping properties) (see Figure 12 below). , the same applies to FIGS. 17 and 18).

A first characteristic P11 in FIG. 11 indicates the amount of vibration reduction at the flange joint of the comparative example. In the comparative example, a flange joint in which a damping adhesive is interposed between the lower flange portion 52A and the flat plate member 3 was used. The second characteristic P12 and the third characteristic P13 indicate the amount of vibration reduction at the flange joint F21 of this embodiment. The second characteristic P12 indicates the amount of vibration reduction when the damping adhesive 6 is attached to the tip end edge 522 of the lower flange portion 52A, as shown in FIG. Further, the third characteristic P13 indicates the amount of vibration reduction when the damping adhesive 6 is attached to the root side edge 521 of the lower flange portion 52A, as shown in FIG.

As is clear from the graph of FIG. 11, the second and third characteristics P12 and P13 in which the damping adhesive 6 is attached to the edge of the lower flange portion 52A are the same as those of the comparative example in the region where the storage modulus is 100 MPa or more. 1. It can be seen that the vibration reduction amount is better than that of the characteristic P11. It can also be seen that the third characteristic P13 of the root side edge 521 has a better vibration reduction amount than the second characteristic P12 of the tip side edge 522. In particular, the region around the storage modulus of 1000 MPa indicated by the symbol a in FIG. 11 is the range of the storage modulus of the damping adhesive 6 that is preferably used. In this range, the second and third characteristics P12 and P13 of the present embodiment show a better vibration reduction amount than the first characteristic P11 of the comparative example, and the flange joint F21 has excellent vibration damping properties. It turns out that it can be built.

FIG. 12 shows the amount of vibration reduction in the case of overlapping bonding in which bonding is performed using only the damping adhesive 6. Similarly to FIG. 11, the first characteristic P11 is a comparative example of the damping adhesive interposed type, the second characteristic P12 is when the damping adhesive 6 is attached to the tip side edge 522, and the third characteristic P13 is the case where the damping adhesive 6 is attached to the distal end edge 522. The amount of vibration reduction when the damping adhesive 6 is attached to the edge 521 is shown. In addition, since there is no spot joint SW and the relative movement between the flat plate member 3 and the lower flange 52A is likely to occur, the strain energy shared by the damping adhesive 6 is the same as that of the well bond joint type shown in FIG. It is an order of magnitude larger than that.

The overlapping bonding shown in FIG. 12 also produced similar results to the well bonding bonding shown in FIG. 11. The second and third characteristics P12 and P13 have a better vibration reduction amount than the first characteristic P11 of the comparative example in a region where the storage modulus is 100 MPa or more. Further, the third characteristic P13 of the root side edge 521 shows a better vibration reduction amount than the second characteristic P12 of the tip side edge 522. The same holds true in the region around the storage modulus of 1000 MPa, which is indicated by the symbol a. Therefore, it can be seen that, according to the present embodiment, the flange joint portion F21 having excellent vibration damping properties can be constructed even by overlapping joints.

[Scattered application of damping adhesive]
As illustrated in FIGS. 5 and 6, in the above embodiment, in the coating step M3 (FIG. 7), along the edge (base side edge 521 or tip side edge 522) of the lower flange portion 52A, An example is shown in which the damping adhesive 6 is applied continuously. Alternatively, the application step M3 may be a step of intermittently applying the damping adhesive 6 so that the damping adhesive 6 is present on a part of the edge of the lower flange portion 52A. In other words, a region where the damping adhesive 6 is not applied may be provided at the edge of the lower flange portion 52A. The area where the damping adhesive 6 is not applied becomes an unrestricted portion where the flat plate member 3 and the lower flange portion 52A are not restricted. This makes it possible to concentrate vibration energy on the portion to which the damping adhesive 6 is applied without unnecessarily restraining both, thereby increasing the vibration damping effect.

In particular, it is desirable that the coating step M3 be a step of coating the edge of the lower flange portion 52A in narrow dots. That is, it is desirable to apply the damping adhesive 6 so that one dotted damping adhesive 6 is provided on the edge, or a plurality of dotted damping adhesive 6 are scattered along the edge. With such a coating process M3, it is possible to manufacture the vehicle body 1 that exhibits the maximum vibration damping effect with a small amount of the damping adhesive 6 used.

FIG. 13 is a perspective view showing an example in which the damping adhesive 6 is arranged in a scattered manner on the edge of the lower flange portion 52A. In FIG. 13, directions of XYZ are indicated. The X direction in the figure is a direction along the bending line FA (edge of the flange portion 52A) of the lower flange portion 52A with respect to the base plate 51 in the reinforcing member 5. Hereinafter, the X direction will be treated as the flange width direction X. The +Y direction is a direction in which the lower flange portion 52A extends from the root side edge 521. The +Z direction is a direction in which the reinforcing member 5 is erected with respect to the flat plate member 3. The flat plate member 3 and the lower flange portion 52A exist in the XY plane, and the base plate 51 exists in the XZ plane.

In FIG. 13, an example is shown in which three dotted damping adhesives 6A, 6B, and 6C are arranged dotted (intermittently) in the flange width direction X on the root side edge 521 of the lower flange portion 52A. It shows. Specifically, the damping adhesive 6A is arranged at one end (-X end) of the root side edge 521, the damping adhesive 6B is arranged at the other end (+X end), and the damping adhesive 6C is arranged at the midpoint in the flange width direction X. has been done. Of course, the damping adhesives 6A, 6B, and 6C are applied so as to adhere to both the flat plate member 3 and the lower flange portion 52A. Furthermore, three dotted damping adhesives 6A, 6B, and 6C may be arranged on the distal end edge 522 (the same applies to the embodiments shown in FIGS. 14 to 16).

In addition, instead of being scattered, each damping adhesive 6A, 6B, and 6C is made wide, and the damping adhesive is intermittently bonded from the -X end to the +X end of the root side edge 521 so that the non-applied part is narrow. Materials may be placed. Furthermore, in the flange joint F21, the vibration mode is analyzed to identify a location that is likely to swing, and the damping adhesive 6 is placed at that location and not at other locations. It is desirable to do so. Thereby, the vibration damping effect of the flange joint portion F21 can be further enhanced.

14 to 16 are perspective views showing other examples in which the damping adhesive 6 is arranged in a scattered manner on the edge of the lower flange portion 52A. FIG. 14 shows an example in which only one point-like damping adhesive 6D is disposed at the midpoint in the flange width direction X on the root side edge 521 of the lower flange portion 52A. Note that the damping adhesive 6D may be arranged at a position away from the midpoint in the flange width direction X to the -X side or the +X end.

FIG. 15 shows an example in which damping adhesives 6E and 6F are scattered at both ends in the flange width direction X at the root side edge 521 of the lower flange portion 52A. Specifically, a dotted damping adhesive 6E is placed at the -X end of the root side edge 521, and a dotted damping adhesive 6F is placed at the +X end. Generally, in the joining flange of the lower flange portion 52A, one end and the other end in the flange width direction X are parts that are likely to swing when vibration is applied. By scatteredly arranging the damping adhesives 6E and 6F in these parts, it is possible to further enhance the vibration damping effect.

FIG. 16 shows an example in which damping adhesives 6G and 6H are scattered at positions spaced apart by a predetermined distance d toward the center from both ends in the flange width direction X on the root side edge 521 of the lower flange portion 52A. ing. Specifically, the dotted damping adhesive 6E is placed at a position spaced apart from the −X end of the root side edge 521 by a distance d toward the center in the flange width direction X. Further, dotted damping adhesive 6H is arranged at a position spaced apart from the +X end by a distance d toward the center in the flange width direction X. According to this embodiment, it is possible to prevent the gap between the damping adhesives 6G and 6H from becoming too large. Therefore, lifting of the lower flange portion 52A in the central region in the flange width direction X can be suppressed.

Even when the damping adhesives 6A to 6H are applied in a dotted manner as described above, the manufacturing method is the same as the process chart shown in FIG. That is, after finishing the coating step M3 in which the damping adhesives 6A to 6H are applied in a dotted manner, a temporary curing step M4 is performed to temporarily harden the damping adhesives 6A to 6H. After passing through the cleaning step M5 and the electrodeposition coating step M6, a drying step M7 which also serves as the main curing of the damping adhesives 6A to 6H is performed.

[Vibration damping effect of damping adhesive material arranged in a dotted manner]
17 and 18 are graphs showing the amount of vibration reduction when the damping adhesive 6 is disposed in a scattered manner on the lower flange portion 52A of the reinforcing member 5. FIG. 17 shows the amount of vibration reduction in the case of well bond bonding in which spot bonding portion SW is also used. FIG. 18 shows the amount of vibration reduction in the case of overlapping bonding in which bonding is performed using only the damping adhesive 6. As mentioned above, the horizontal axis of the graph is the storage modulus [MPa] of the test material, and the vertical axis of the graph is the strain energy sharing ratio [MPa], which is an index indicating the amount of vibration reduction during cross-sectional deformation of the vehicle body structure 2. %].

As illustrated in FIG. 5, the first characteristic P21 (continuous) in the figure indicates that the damping adhesive 6 is continuously applied over the entire length in the flange width direction X at the root side edge 521 of the lower flange portion 52A. This shows the amount of vibration reduction when The second characteristic P22 (intermittent) is obtained when three dotted damping adhesives 6A, 6B, and 6C are disposed intermittently in the flange width direction X on the root side edge 521, as shown in FIG. is the amount of vibration reduction. The third characteristic P23 (center) is the amount of vibration reduction when one point-shaped damping adhesive 6D is placed at the center of the flange width direction X, as shown in FIG. As shown in FIG. 15, the fourth characteristic P24 (end) is the vibration reduction when point-shaped damping adhesives 6E and 6F are placed at both ends of the root side edge 521 in the flange width direction X. It's the amount. As shown in FIG. 16, the fifth characteristic P25 (intermediate) has dotted damping adhesives 6G and 6H at positions spaced apart from each other by a distance d from both ends of the root side edge 521 in the flange width direction X. This is the amount of vibration reduction when installed.

As is clear from the graph in FIG. 17, in the case of well bond bonding, the second characteristic P22 (intermittent), the fourth characteristic It can be seen that P24 (end) and the fifth characteristic P25 (intermediate) have better vibration reduction amounts than the first characteristic P21 (continuous). In particular, the fourth characteristic P24 (end portion) shows an excellent amount of vibration reduction. Note that the third characteristic P23 (center) indicates a lower vibration reduction amount than the first characteristic P21 (continuous) near 1000 MPa. However, by changing the arrangement position of the damping adhesive 6D, or by changing the position of the spot joint SW or the shape of the flange, it is possible to achieve a good vibration reduction amount.

As is clear from the graph of FIG. 18, in the case of overlap bonding, all of the second to fifth characteristics P22 to P25, in which the damping adhesive 6 is arranged in a dotted manner, are better than the first characteristic P21 (continuous) at around 1000 MPa. It can be seen that the same has a good vibration reduction amount. Here, the third characteristic P23 (center) also shows a particularly excellent amount of vibration reduction, along with the fourth characteristic P24 (edge) and the fifth characteristic P25 (middle). This is because in overlapping joints that are not restrained by the spot joint SW, the lower flange portion 52A can move in parallel to the flat plate member 3, so strain energy tends to concentrate on the damping adhesives 6A to 6H. It is thought that this is because

According to the present embodiment described above, before the drying step M7 in which the damping adhesive 6 is fully cured, the temporary curing step M4 is performed in which the damping adhesive 6 applied in the coating step M3 is temporarily cured. Therefore, even if the damping adhesive 6 is exposed to the outside in a manner adjacent to the root side edge 521 or the tip side edge 522 of the lower flange portion 52A, the applied damping adhesive 6 is temporarily cured. This makes it possible to maintain the original coating shape. Therefore, it is possible to manufacture the vehicle body 1 in which the damping adhesive 6 can exhibit the desired damping effect.

Furthermore, if a configuration is adopted in which the damping adhesives 6A to 6H are arranged in a scattered manner on the root side edge 521 or the tip side edge 522 of the lower flange portion 52A, vibration energy can be transferred to these damping adhesives 6A to 6H. can be concentrated to further enhance the vibration damping effect.

[Modified example]
Although the embodiments of the present invention have been described above, the present invention is not limited thereto. For example, in the above-described embodiment, the rust preventive drying process M7 is used as the process of main curing the damping adhesive 6. Instead, a heating step for main curing of the damping adhesive 6 may be performed separately. For example, a main curing process of the damping adhesive 6 may be performed before the cleaning process M5.

1 Vehicle body 2 Vehicle body structure 3 Flat plate member (first vehicle body member)
4 Hat-shaped member 5 Reinforcement member (second vehicle body member)
51 Base plate 52A Lower flange part (flange part)
521 Root side edge (edge of flange part)
522 Tip side edge (edge of flange part)
6, 5A to 6H Damping adhesive (vibration damping member)
F21 Flange joint SW Spot joint C Closed section FA Bending line X Flange width direction

Claims (6)

A method for manufacturing a vehicle body using a first vehicle body member and a second vehicle body member having a flange portion, the method comprising:
a superposition step of overlapping the first vehicle body member and the flange portion of the second vehicle body member;
a coating step of applying a thermosetting vibration damping member to an edge of the flange portion so as to adhere to the first vehicle body member and the flange portion;
a temporary curing step of temporarily curing the applied vibration damping member;
a main curing step of curing the pre-hardened vibration damping member with heat;
Between the temporary curing step and the main curing step, another treatment step is performed on the first vehicle body member and the second vehicle body member;
A method for manufacturing a vehicle body, comprising: The method for manufacturing a vehicle body according to claim 1 ,
The method for manufacturing a vehicle body, wherein the temporary curing step is a step of applying heat to the vibration damping member to temporarily harden the vibration damping member. The method for manufacturing a vehicle body according to claim 1 ,
The vibration damping member is a material that can be cured by irradiation with light,
The method for manufacturing a vehicle body, wherein the temporary curing step is a step of irradiating the vibration damping member with light to temporarily harden it. In the method for manufacturing a vehicle body according to any one of claims 1 to 3 ,
The method for manufacturing a vehicle body, wherein the application step is a step of applying the vibration damping member so that the vibration damping member is present on a part of the edge of the flange portion. The method for manufacturing a vehicle body according to claim 4 ,
The method for manufacturing a vehicle body, wherein the application step is a step of applying the vibration damping member so that the vibration damping member is scattered at an edge of the flange portion. In the method for manufacturing a vehicle body according to any one of claims 1 to 5 ,
A method for manufacturing a vehicle body, further comprising a welding step of spot welding the first vehicle body member and the flange portion after the polymerization step.

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