JP5673469B2 - Connection structure and connection method - Google Patents

Description

  The present invention relates to a connection structure in which two or more members to be connected are connected via a self-piercing rivet, and a connection method of connecting using a self-piercing rivet.

  Fiber reinforced resin members (fiber reinforced plastics, FRP), in which fiber materials for reinforcement are mixed with resin, are lightweight and high in strength, so they are used in various industrial fields such as the automobile industry, construction industry, and aviation industry. ing.

  And about the joining method of fiber reinforced resin members, the method of joining via an adhesive agent, the joining method by a volt | bolt, Furthermore, the joining method etc. which combined them are generally used.

  By the way, regarding the joining of members, when the member to be joined is made of an aluminum plate, a steel plate or the like, there are various joining methods such as spot welding, friction stir welding, mechanical clinching, brazing, and screwing. May be applied.

  This self-piercing rivet joining method is a self-piercing rivet comprising, for example, two metal plates placed in a stacked posture on the top surface of a rivet die, and an end surface and a cylindrical body (pierce) protruding from the end surface. Is positioned above the metal plate and punched into the metal plate by punching the barrel into the upper plate. In this process, the tip of the barrel is expanded while plastically deforming outward, and the barrel is further expanded. By driving in, the tip is further expanded in the lower plate, and the upper and lower metal plates are also plastically deformed in the process of driving the barrel, and both are interlocked via the barrel.

  According to the joining method using the self-piercing rivet, for example, it is not necessary to make a hole in advance on the metal upper plate, and further, it is possible to join three or four metal plates to each other. These metal members can be joined with high strength. For example, Patent Document 1 discloses a technique in which the thickness of the front end portion of the body portion is relatively thinner than the root portion in order to enhance the caulking effect by the self-piercing rivet.

  By the way, an attempt has been made to apply the joining method by the self-piercing rivet having various merits as described above to joining two or more members made of the above-described resin members (including fiber reinforced resin members).

  However, when the joining method using the self-piercing rivet is applied to the connection between the connected members made of two resin members in this way, the matrix resin is broken by the piercing of the tip of the rivet, and the rivet and the resin member are like a metal plate. It becomes difficult to be fixed enough. One of the causes of the matrix resin cracking caused by the rivet tip is that the tip of the barrel fixed inside the lower connected member does not curl sufficiently (does not roll up sufficiently), so It is considered that the distance between the lower surface and the front end of the body portion becomes too short inside the connecting member, and the pressure from the front end of the body portion acts on the distance.

  Further, due to the lack of curling at the tip of the body portion, the caulking effect by the self-piercing rivet tends to be insufficient, which leads to a problem that it is difficult to obtain a desired connection strength. In addition, when the thing of the variable cross-section structure where the trunk | drum which comprises a self-piercing rivet becomes thin from the middle position as disclosed by patent document 1 mentioned above is applied, since the front-end | tip of a trunk | drum is thin. However, the self-piercing rivet with a variable cross-section structure has a structural mechanics problem that stress tends to concentrate in the cross-section change area, and this can easily lead to damage to the body itself. It is hard to say that it is a preferred self-piercing rivet.

JP 2007-64439 A

  The present invention has been made in view of the above-described problems, and relates to a connection structure and a connection method in which two or more members to be connected are connected via a self-piercing rivet, and sufficient winding of a body portion constituting the self-piercing rivet. It is an object of the present invention to provide a connection structure and a connection method in which a high connection strength can be obtained by a high caulking effect due to rising, and there is no risk of damage to a body portion which is a component due to stress concentration or the like.

  In order to achieve the above object, the connection structure according to the present invention has a double tube structure in which the ends of the two trunks have peaks and valleys alternately, and the peaks of the trunks overlap each other. Self-piercing rivets that are arranged so as not to be displaced are driven into the overlapping positions of the plurality of connected members, and inside the connected members at the final position in the driving direction, The overlapping portions are connected so as to spread radially so that the peaks do not intersect.

  The connection structure of the present invention relates to a structure in which two or more members to be connected are connected by a self-piercing rivet having a cylindrical body (pierce), and the body has a double-pipe structure, and each tip has a mountain. It is connected with a self-piercing rivet with a novel structure that has never existed so that the crests and troughs are alternately arranged and the crests of both are arranged so as not to overlap. .

  The shape of the ridge at the tip of the torso can be a shape that is sharp in the direction of driving the torso (triangle, semi-elliptical, sharp shape at the tip of the semi-ellipse, etc.). The number of crests and troughs provided alternately in the circumferential direction (for example, the pitch between the crests) is less likely to interfere with the outer trunk when the crests of the inner trunk that has been driven in spread radially. That is, it can be set from the viewpoint of having a number of peaks that can achieve a desired caulking effect.

  According to the connection structure of the present invention, the crests at the tips of both the outer and inner body parts are shifted, and both crests are radially expanded (opened) to the final position in the driving direction. Because it stays inside a certain connected member, it tends to be plastically deformed and spread inside the connected member as compared to the cylindrical barrel portion that constitutes a conventional self-piercing rivet, and more easily curls. High caulking effect can be expected.

  In addition, since the barrel itself does not have a variable cross-sectional structure (a structure with different wall thickness), there is no part where stress is concentrated when driving, and the problem is that the barrel is damaged due to stress concentration. It cannot happen.

  In addition to the double-pipe structure, it is easier to curl the peaks by adjusting the outer and inner barrels to be thinner than the conventional barrel. From the viewpoint of For example, when the thickness of the body part constituting a conventional self-piercing rivet is about 1 mm, both the outer body part and the inner body part can be set to have a thickness of about 0.5 mm.

  Moreover, although it is based on a double tube structure, modifications such as a triple tube structure or a quadruple tube structure in which body portions having different diameters are arranged on the outside or the inside thereof may be used. Thus, even in the case of a barrel portion such as a triple tube structure, the ridges of each of the plurality of trunk portions that are constituent members are shifted from each other, for example, when the ridge portion of the innermost barrel tip spreads radially, It is desirable to adjust the size, pitch, and the like of the ridges at the front ends of the respective body parts so as not to interfere with the two outer body parts.

  In addition, “a plurality of connected members” forming a connection structure means that, for example, two connected members are both metal members (two aluminum (alloy) plates, aluminum (alloy) plate and copper (alloy) plate, steel plate and aluminum). (Alloy), etc.) One of the two connected members is a metal member and the other is a resin member (a thermosetting resin member or a thermoplastic resin member that is not mixed with fiber material, continuous fiber, long fiber, short fiber, etc. The fiber reinforced resin member in which a fiber material such as fiber is mixed) and the like. In addition, three or more connected members are also targets, and either one of the above-described metal members or resin members, or a form in which both are mixed (the uppermost layer is made of a metal member, and the intermediate layer and the lowermost layer are made of a thermoplastic resin. Fiber reinforced resin member).

  The present invention also extends to a connection method. In this connection method, each tip of a plurality of trunks forming a double tube structure has peaks and valleys alternately, Prepare a self-piercing rivet that is shifted so that the peaks do not overlap, and drive the outer body part ahead of the place where the multiple connected members overlap, leaving the time difference inside. The body portions are driven in such a manner that the overlapped portions are radially connected so as not to intersect the crests at the front ends of the respective body portions within the connected member at the final position in the driving direction.

  In the connection method of the present invention, a time difference is provided in driving the inner and outer barrels of the double pipe structure, the outer barrel is driven in advance, and the crests at the tip thereof are radially spread, By driving the inner torso and expanding the crest at its tip radially, the inner torso does not interfere with the outer torso when it expands, making it difficult to interfere. In addition, it is possible to effectively widen the ridges of both the outer and outer body portions radially.

  Here, “with a time lag” means that after the outer body is driven and the crest is completely expanded, the inner body is driven and expanded, and the outer crest is plastic. It also means that the inner body starts to be driven while deforming and spreading, and the time difference is set in a manner that can avoid interfering with each other with respect to the spread of both the inner and outer ridges. Is.

  Here, as an embodiment in which the outer and inner body portions are driven in with a time difference, the following two embodiments can be given.

  One of the forms is characterized by a punch for punching the barrel. In the punch for punching the barrel, the central region is used for driving the inner barrel, and the outer region is provided with an elastic member. An annular punch is provided so as to protrude from the central region, and when the punch is slid toward the connected member side, the annular punch precedes and pushes the outer body, leaving a time difference. The center area of the punch pushes the inner body part.

  As a form of the punch to be used, one punch is a basic structure, the central region is driven into the inner barrel, and an annular punch is arranged on the outer region of the punch via an elastic member such as a spring. The form currently provided in the position which protruded in the self-piercing rivet side rather than the center area | region of this can be mentioned. The term “elastic member” as used herein includes a piston that slides in the cylinder by hydraulic pressure or air pressure. An annular cylinder mechanism is built in the outer peripheral area of the punch, and the piston is in the central area of the punch. The form which is the attitude | position which protruded from the self-piercing rivet side can be mentioned.

  Further, the punch may have a double tube structure, and the inner and outer punches may be pushed into the inner and outer barrels, respectively.

  On the other hand, another embodiment in which the outer and inner barrels are driven with a time lag is a feature in which the punch is driven by a double tube structure, and the inner barrel is pressed by the punch. The surface has fallen to the connected member side from the pressing surface of the outer body part, and when the punch is slid to the connected member side, the outer body part is pushed in first, leaving a time difference inside. This is a form in which the body part of the body is pushed.

  Regardless of the form with the above-mentioned punch structure or the form with the double-pipe structure body, the inner body is placed with a desired time difference after the outer body is driven. , And the crests at both the inner and outer body tips can be effectively spread radially.

  According to the connection method of the present invention described above, while adopting the body portion of the double-pipe structure, it is possible to effectively widen the ridges at both ends radially, and plastic deformation so as to wind up further upward. Therefore, cracks are unlikely to occur at the tip of the crest in the connected member at the final position in the driving direction, and the overlapping portions of two or more connected members are connected with high connection strength by the caulking effect. be able to.

  As can be understood from the above description, according to the connection structure of the present invention, it is composed of two barrels forming a double tube structure, and the tips of both the inner and outer barrels alternate between peaks and valleys. And connecting the overlapping portions of two or more connected members by applying a self-piercing rivet that is arranged so as to be shifted so that both peak portions do not overlap with each other. It is possible to expect plastic deformation such that the crests are effectively plastically deformed and spread radially and curl, and a connection structure having excellent caulking effects and high connection strength can be obtained. Further, according to the connection method of the present invention, when the outer body portion is driven and the inner body portion is driven with a time difference, the outer body portion is expanded when the mountain portion of the inner body portion is plastically deformed and spreads. Without being interfered with, the crests of both the inner and outer body portions can be effectively spread radially, and a connection structure having high connection strength can be formed.

It is a perspective view of one embodiment of the self-piercing rivet forming one embodiment of the connection structure of the present invention. It is the II-II arrow line view of FIG. 1, and is a longitudinal cross-sectional view of one embodiment of the self-piercing rivet. (A), (b), (c) is the schematic diagram which showed embodiment of the peak part and trough part formed in the front-end | tip of a trunk | drum. It is a figure explaining one Embodiment of the connection method of this invention. (A) is the Va-Va arrow directional view of FIG. 4, (b) is the Vb-Vb arrow directional view of FIG. It is the figure explaining the connection method of this invention following FIG. It is the figure explaining the connection method of this invention following FIG. (A) is the schematic diagram explaining the connection structure formed with the connection method of this invention, (b) is a bb arrow line view of FIG. 8a. It is a longitudinal cross-sectional view of other embodiment of the self-piercing rivet which forms other embodiment of the connection structure of this invention. It is a figure explaining other embodiment of the connection method of this invention.

  Embodiments of a connection structure and a connection method of the present invention will be described below with reference to the drawings. Although the illustrated example shows the connection structure and connection method of two connected members, it is needless to say that the connection structure and connection method of three or more connected members may be used.

(Embodiment 1 of self-piercing rivet)
1 is a perspective view of Embodiment 1 of a self-piercing rivet forming Embodiment 1 of the connection structure of the present invention, and FIG. 2 is a view taken along the line II-II of FIG. It is a longitudinal cross-sectional view of the first embodiment.

  The illustrated self-piercing rivet 10 has a double-pipe structure composed of an outer tube 1 and an inner tube 2 formed of aluminum, an alloy thereof, steel, or the like, and is configured as a whole.

  The outer tube 1 is alternately formed in the circumferential direction at the head 1d that is directly pushed by a punch (not shown), the cylindrical body 1a integrated with the head 1d, and the front end of the body 1a. It is comprised from the peak part 1b and the trough part 1c.

  The basic structure of the inner tube 2 is the same as that of the outer tube 1, and the head 2d, the cylindrical body 2a integrated with the head 2d, and the tip of the body 2a are alternately arranged in the circumferential direction. It is comprised from the formed peak part 2b and the trough part 2c.

  Then, in the double tube structure of the outer tube 1 and the inner tube 2, as shown in FIG. 1, the peak portion 1b of the tip portion of the barrel portion 1a of the outer tube 1 and the peak portion 2b of the tip portion of the barrel portion 2a of the inner tube 2 are provided. Are positioned so as not to cross each other (therefore, when viewed from the outside as shown in FIG. 1, the peak 2b at the tip of the barrel 2a is separated from the trough 1c at the tip of the barrel 1a. Visible).

  Thus, since both peak parts 1b and 2b are mutually shifted, both the trunk parts 1b and 2b are driven into the overlapping part of two to-be-connected members so that it may mention later. It is possible to effectively eliminate the interference between the crest 2b that tends to spread outward and the body 1a of the outer tube 1 when plastically deformed and spread in the radial direction.

  3a, 3b, and 3c are all schematic views showing an embodiment of a crest and a trough formed at the tip of the trunk.

  The peak 1b and the valley 1c shown in FIG. 3a are forms corresponding to FIG. 1, and the peak 1b and the valley 1c are formed so as to form a triangle. On the other hand, each of the crest 1b 'and the trough 1c' shown in FIG. 3b has a semi-elliptical shape with a sharpened tip. Further, the peak 1b ″ shown in FIG. 3c has a semi-elliptical shape, and the valley 1c ″ has a semi-circular shape.

  In any form, the number of crests and troughs (pitch of crests) is such that when the crests 2b, 2b ', 2b' 'of the inner cuff 2a that has been driven open, the outer trunk 1a And a structure having a number of peaks 1b, 2b, 1b ′, 2b ′, 1b ″, 2b ″ that can obtain a desired caulking effect.

  Further, both the outer body portion 1a and the inner body portion 2a are thinner than the body portion of the conventional structure, and it is easy to curl the mountain portions 1b, 2b, etc. (to be rolled up by plastic deformation). From the above viewpoint, for example, when the thickness of the body part constituting a conventional general self-piercing rivet is about 1 mm, both the outer body part and the inner body part are set to have a thickness of about 0.5 mm. Is good.

  A method for connecting two connected members using such a self-piercing rivet 10 having a double-pipe structure and a connection structure formed by this method will be described below.

(Embodiment 1 of connection method and connection structure)
4, 6, and 7 are flowcharts for explaining a connection method of two connected members in this order, and FIG. 8 a shows a connection structure formed by this connection method.

  First, an overlapping portion of the two connected members W1 and W2 is placed on the top surface 5a of the rivet die 5, and a cylinder mechanism in which the punch 3 can slide in the cylinder 4 is placed above the overlapping portion. Arrange.

  The rivet die 5 has a circular planar shape (not shown), and an annular concave groove 5b is formed on the top surface 5a on which the connected member W2 is placed. Moreover, the form which incorporated heating means, such as a heater, in the inside may be sufficient. The annular concave groove 5b serves to guide plastic deformation (direction) of the crests 1b and 2b of the outer and inner body parts 1a and 2a constituting the self-piercing rivet 10.

  5a is a view taken along the line Va-Va in FIG. 4, and FIG. 5b is a view taken along the line Vb-Vb in FIG. 4, in which the punch 3 is viewed in a separate plane section.

  The punch 3 has a circular shape and is complementary to the hollow shape of the cylindrical cylinder 4. Furthermore, it comprises a central region 3a for pushing the head 2d of the inner pipe 2 constituting the self-piercing rivet 10 and an outer region 3b on the outer periphery thereof, and an annular groove 3b ′ is formed in the outer region 3b. Here, a plurality of springs 3c (elastic members) are provided, and an annular punch 3d is attached to the springs 3c.

  As shown in FIG. 4, in the initial stage of pushing the punch 3, the annular punch 3 d protrudes toward the self-piercing rivet 10 as compared with the central region 3 a of the punch 3. The center region 3 a of the punch 3 is separated from the head portion 2 a of the inner tube 2, while being in contact with the head portion 1 d of one.

  The connected members W1 and W2 to be connected are both metal members (both aluminum (alloy) plate, aluminum (alloy) plate and copper (alloy) plate, steel plate and aluminum (alloy) plate, etc.)), one of which is metal Either the member may be a resin member or the other may be a resin member.

  In the case of a resin member, the matrix resin includes crystalline plastics such as polyethylene (PE), polypropylene (PP), polyamide (PA: nylon 6, nylon 66, etc.), polyacetal (POM), polyethylene terephthalate (PET), Thermosetting resins such as polystyrene (PS), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), ABS resin, amorphous plastic such as thermoplastic epoxy, epoxy resin, phenol resin, polyurethane, etc. A material obtained by mixing any one of the resins, or a mixture of two or more of the thermoplastic resins and the thermosetting resins can be used.

  When the matrix resin contains a fiber material (short fiber, long fiber, continuous fiber) (therefore, the connected member is a fiber reinforced resin member), the fiber material may be boron, alumina, silicon carbide. , Ceramic fiber such as silicon nitride and zirconia, inorganic fiber such as glass fiber and carbon fiber, metal fiber such as copper, steel, aluminum and stainless steel, organic fiber such as polyamide and polyester, or a mixture of two or more kinds Can be applied.

  When the preparation for driving the self-piercing rivet 10 is completed as shown in FIG. 4, the punch 3 is slid in the cylinder 4 and pushed down with a pressing force Q as shown in FIG. The head 1d of the outer tube 1 with which the annular punch 3d is in contact is pushed downward through the spring 3c (pushing force Q1).

  Until the outer tube 1 is pushed to some extent, the central region 3a of the punch 3 does not come into contact with the head 2d of the inner tube 2, so that the inner tube 2 is not pushed.

  FIG. 6 shows a state in which the outer tube 1 is pushed to some extent and the crest 1b at the tip of the body 1a is plastically deformed while receiving pressure q from the inside, and radially spreads outward. At this stage, The central region 3a of the punch 3 contacts the head 2d of the inner tube 2 with a time difference. In this way, the plurality of springs 3c have a rigidity that allows the outer tube 1 to be pushed into the two connected members W1 and W2 via the annular punch 3d, as shown in FIG. As shown by the above, the elastic member is elastic so as to be accommodated in the concave groove 3b ′ while contracting in the annular concave groove 3b ′ by the acting pressure.

  When the punch 3 is further pushed in, as shown in FIG. 7, the central region 3a of the punch 3 pushes the head 2d of the inner tube 2 (pushing force Q2), and the inner tube 2 is placed with a time difference from the driving of the outer tube 1. Are driven into the two connected members W1 and W2, and the crest 2b at the tip thereof is plastically deformed, spreads radially beyond the trough 1c at the tip of the outer tube 1, and further curled and fixed as shown in the figure. The

  The self-piercing rivet 10 is driven in until the heads 1d and 2d are flush with the upper surface of the upper connected member W1, and the outer and inner peaks 1b and 2b are sufficiently plastically deformed (curled) and lowered. After fixing in the connected member W2, the connecting structure 100 shown in FIG. 8a is formed by taking it out from the manufacturing system.

  If the rivet die 5 has a built-in heater, the connected member W2 made of, for example, a thermoplastic resin is preheated and softened by the heater, and then the sliding of the punch 3 is performed. May be.

  FIG. 8B is a view taken along the line bb in FIG. 8A and is a view of the inner and outer peaks 1b and 2b in the formed connection structure 100 as viewed from below.

  As shown in FIG. 8b, both the crests 1b and 2b are displaced from each other, so that both crests 1b and 2b are radially plastically deformed and curled further without interfering with each other. Thus, it is fixed in the lower connected member W2.

  As is apparent from the figure, the outer and inner ridges 1b and 2b are plastically deformed and spread radially, so that the tip of the cylindrical barrel is plasticized like a conventional self-piercing rivet. Compared with the case of deforming and expanding radially, the tip of the body portion is deformed smoothly, and the upward curling (curl) is likely to be curled.

(Embodiment 2 of self-piercing rivet and connection method)
FIG. 9 is a longitudinal sectional view showing a second embodiment of the self-piercing rivet forming another embodiment of the connection structure of the present invention, and FIG. 10 is a diagram for explaining the second embodiment of the connection method. is there.

  In the self-piercing rivet 10A shown in FIG. 9, the head part of the inner trunk part 2A falls to the connected member side with respect to the head part of the outer trunk part 1A. It is formed shorter than the portion 1A.

  By applying this self-piercing rivet 10A, as shown in FIG. 10, the outer tube 1A is first pushed by sliding it continuously in the cylinder 4 using a conventional general punch 3A, Next, the inner tube 2A is pushed in with a time lag, and the crests at the tips of both barrels are plastically deformed radially to form a connection structure (not shown).

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

DESCRIPTION OF SYMBOLS 1,1A ... Outer pipe | tube, 1a ... Outer trunk | drum, 1b, 1b ', 1b "... Mountain part, 1c, 1c', 1c" ... Valley part, 1d ... Head part, 2, 2A ... Inner pipe | tube, 2a ... Inner trunk, 2b ... mountain, 2c ... valley, 2d ... head, 3 ... punch, 3a ... central region, 3b ... outer region, 3b '... annular groove, 3c ... elastic member (spring), 3d ... annular punch, 4 ... cylinder, 5 ... rivet die, 5a ... top surface, 5b ... concave groove, 10, 10A ... self-piercing rivet, 100 ... connection structure, W1, W2 ... connected member

Claims (5)

  Self-piercing rivets in which the tip of each of the two barrels forming a double-pipe structure has ridges and valleys alternately, and are shifted so that the ridges of each barrel do not overlap. Is driven into the overlapping location of a plurality of connected members, and the overlapping is performed by spreading radially so that the crests at the ends of the respective body portions do not intersect within the connected member at the final position in the driving direction. Connection structure that connects locations.   The connection structure according to claim 1, wherein each of the plurality of connected members is made of any one of a resin member and a fiber reinforced resin material. Self-piercing rivets in which the tip of each of the two barrels forming a double-pipe structure has ridges and valleys alternately, and are shifted so that the ridges of each barrel do not overlap. Prepare
For each overlapped portion of the plurality of connected members, the outer body portion is driven in advance, the inner body portion is driven with a time difference, and each of the connection members at the final position in the driving direction A connection method in which the overlapping portions are connected in a radial manner so as not to intersect the crests at the tip of the trunk.   In the punch for driving the body portion, the central region is used for driving the inner body portion, and an annular punch is provided in the outer region so as to protrude from the central region via an elastic member. The connecting method according to claim 3, wherein when the slidable member is slid toward the member to be connected, the annular punch precedes and pushes the outer barrel, and the central region of the punch pushes the inner barrel with a time lag. . The pressing surface by the punch of the inner trunk part falls to the connected member side than the pressing surface of the outer trunk part,
The connection method according to claim 3, wherein when the punch is slid toward the connected member side, the outer body part is pushed in first, and the inner body part is pushed with a time lag.

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