Resistance rivet, connector and method of connecting

Abstract

The present application relates to a kind of resistance rivet welding rivets, including riveting part, the riveting part is used to with the first plate material puncture riveting, and forms the excess fit connection;Welding part, the welding part is from the second end surface of the riveting part outwardly protruding, and the second end surface of the welding part is set as circular arc surface, the circular arc surface is used to contact with the second plate material before welding, to push away the non-conductive structural glue coated on the first end surface of the second plate material along radial;Wherein, the outer diameter of the riveting part is greater than the outer diameter of the welding part.The present application can be achieved by the fastening of the first plate material in the radial inner recess of the anti-drop groove, and the effect of anti-loosening is good, and the welding quality is improved by pushing away the non-conductive structural glue by the welding part of local setting and additional protrusion.

Description

Technical Field

[0001] This invention relates to an automotive fastener, and more particularly to a resistance-welded rivet. Background Technology

[0002] The description in this section provides only background information related to the disclosure of this invention and does not constitute prior art.

[0003] Resistance spot welding is a common welding technique used to join two metal workpieces together, typically found on assembly lines in industries such as automobiles, fans, and trains. Resistance spot welding involves applying high pressure and a large current between the contact surfaces of two metal workpieces. The heat generated by the contact resistance melts the metal or brings it to a plastic state, forming a weld point. After the power is turned off, the weld point becomes firm under continued pressure, connecting the metal workpieces together. This process usually includes stages such as pre-pressing, welding, holding, and resting.

[0004] Existing resistance riveting technology has several drawbacks in application: First, after the rivet pierces the sheet metal, the bonding force between its root and the sheet metal is limited, making it prone to loosening during transport or press-fitting of the workpiece after riveting. Second, to meet the sealing, corrosion protection, and impact resistance requirements of components such as automotive battery packs, non-conductive structural adhesive is usually coated on the welding surface. Since non-conductive structural adhesive is a non-conductive medium, the presence of adhesive at the welding point will severely interfere with current conduction, leading to quality defects such as spattering of the weld nugget, burn-through, or poor welding.

[0005] It should be noted that the above description of the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of the present invention and facilitating understanding by those skilled in the art. It should not be assumed that the above technical solutions are known to those skilled in the art simply because they have been described in the background section of this invention. Summary of the Invention

[0006] The purpose of this invention is to provide a resistance welding rivet that can fasten the first plate through the radially concave anti-loosening groove of the riveting part, with good anti-loosening effect, and improve the welding quality by using a locally set, additionally protruding welding part to push away non-conductive structural adhesive.

[0007] To achieve the above objectives, the present invention discloses a resistance welding rivet for connecting a first plate and a second plate, the rivet having a first end and a second end disposed opposite to each other along an axial direction, wherein the resistance welding rivet comprises: The riveting part is used for piercing and riveting with the first plate to form an interference fit connection; The welding part protrudes outward from the second end face of the riveting part, and the second end face of the welding part is set as an arc surface. The arc surface is used to contact the second plate before welding so as to push the non-conductive structural adhesive coated on the first end face of the second plate radially away. The outer diameter of the riveted part is larger than the outer diameter of the welded part.

[0008] As a further description of the above technical solution, at least a portion of the sidewall of the riveting part is radially recessed to form an anti-detachment groove, which is used to accommodate at least a portion of the first plate and prevent detachment after the riveting part is riveted to the first plate.

[0009] As a further description of the above technical solution, the welding part protrudes outward from the middle position of the second end face of the riveting part.

[0010] As a further description of the above technical solution, an upper welding point is provided at the middle position of the first end face of the riveting part, and a lower welding point is provided on the second end face of the welding part.

[0011] As a further description of the above technical solution, the welded part has a preset axial thickness, so that after welding, the welded part collapses and deforms along the axial direction to form a molten nugget, and just so that the second end face of the riveted part comes into contact with the second plate.

[0012] As a further description of the above technical solution, the arc of the welded part is set to be between 0° and 1°.

[0013] As a further description of the above technical solution, the riveting part has a preset axial thickness, so that after riveting with the first plate, the first end face of the riveting part is flush with the first end face of the first plate, the second end face of the riveting part is in contact with the second end face of the second plate, and a preset gap is maintained between the first plate and the second plate.

[0014] As a further description of the above technical solution, the anti-detachment groove wall includes a first inclined wall and a second inclined wall connected from the first end to the second end, wherein the included angle between the first inclined wall and the second inclined wall is not 0° or 180°.

[0015] As a further description of the above technical solution, neither the first inclined wall nor the second inclined wall is parallel to the axial direction.

[0016] As a further description of the above technical solution, the outer diameter of the welded part is half the outer diameter of the riveted part, and the outward protrusion of the welded part is between 0.2mm and 0.3mm.

[0017] The present invention also discloses a connector, wherein the connector includes a resistance-welded rivet, a first plate and a second plate, the riveting part of the resistance-welded rivet is riveted to the first plate, the welding part in the middle of the second end of the second end of the resistance-welded rivet is welded to the second plate, the second end face of the riveting part is provided with non-conductive structural adhesive in the annular space between the periphery of the welding part and the second plate, the weld nugget formed by the welding part does not have non-conductive structural adhesive, the first plate and the second plate are arranged in parallel, and the resistance-welded rivet is in a flat state relative to the first plate and the second plate.

[0018] This invention also discloses a method for connecting rivets by resistance welding, comprising the following steps: A first plate is provided, and a rivet is pierced through the first plate in a direction from the first end to the second end; Continuously apply pressure to the rivet, causing the rivet's riveting portion to embed into the first plate, and causing at least a portion of the first plate to enter the anti-dislodgement groove of the riveting sidewall; A second plate is provided, and a non-conductive structural adhesive is coated on the first end face of the second plate. The welded part of the second end of the rivet is attached to the non-conductive structural adhesive. Pressure is applied to the first end face of the riveting part, causing the arc surface of the second end face of the welding part to push the non-conductive structural adhesive away radially and into contact with the second plate. Pressure and current are continuously applied to the first end face of the riveting part, so that the welding part is connected to the second plate and forms a weld nugget connection.

[0019] As a further description of the above technical solution, after the step of "continuously applying pressure and current to the first end face of the riveting part, so that the welding part is connected to the second plate and forms a fusion nugget connection", the second end face of the riveting part is in contact with the first end face of the second plate.

[0020] By employing the above technical solutions, the beneficial effects of the present invention are as follows: The resistance-welded rivet of this invention can securely fasten the first plate through a radially concave anti-loosening groove in the riveting part, providing excellent anti-loosening effect. Furthermore, the locally designed, additionally protruding welding part pushes away non-conductive structural adhesive, improving welding quality. Specifically, the flared anti-loosening groove in this invention utilizes the plastic flow of the material to achieve a strong physical anti-loosening effect, significantly superior to traditional grooveless designs. Simultaneously, thanks to the special structure of the arc-shaped surface of the welding part and the design of the lower welding point with a specific micro-arc, non-conductive structural adhesive can be forcibly expelled during adhesive-bearing welding, ensuring stable electrical signal conduction. This results in extremely high process stability and sealing protection capabilities in mass automated production.

[0021] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a front view of a resistance-welded rivet provided in the embodiments of this specification; Figure 2 This is a schematic diagram of a resistance-welded rivet provided in the embodiments of this specification before welding; Figure 3 This is a schematic diagram of a resistance-welded rivet provided in the embodiments of this specification after welding; Figure 4 This is a three-dimensional schematic diagram of a resistance-welded rivet provided in the embodiments of this specification; Figure 5 This is a schematic diagram of the second plate adhesive application for a resistance riveting rivet provided in the embodiments of this specification; Figure 6 This is a schematic diagram of the welding part of a resistance riveting rivet pushing glue onto a second plate, as provided in the embodiments of this specification. In the picture: 100, First sheet material; 200, Second sheet material; 300, Non-conductive structural adhesive; 1. Riveting part; 11. Anti-detachment groove; 111. First inclined wall; 112. Second inclined wall; 12. Upper weld point; 2. Welding section; 21. Arc surface; 22. Lower weld point; 3. Circular space. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this specification.

[0025] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Furthermore, the accompanying drawings of the present invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of protection of the present invention.

[0026] It should be understood that while terms such as "first," "second," and "third" may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another, or one signal from another. Furthermore, the term "or" as used herein should, as appropriate, include any combination of one or more of the related listed items.

[0027] Please see Figure 1-4 This embodiment provides a resistance welding rivet for connecting a first plate 100 and a second plate 200. The rivet has a first end and a second end disposed opposite to each other along the axial direction. The resistance welding rivet includes: The riveting part 1 is used to pierce and rivet with the first plate 100 to form an interference fit connection; specifically, the side wall of the riveting part 1 is radially recessed to form an anti-detachment groove 11, which is used to accommodate at least a portion of the first plate 100 and prevent detachment after the riveting part 1 is riveted with the first plate 100. Welding part 2, the welding part 2 protrudes outward from the second end face of the riveting part 1, and the second end face of the welding part 2 is set as an arc surface 21. The arc surface 21 is used to contact the second plate 200 before welding, so as to push the non-conductive structural adhesive 300 coated on the first end face of the second plate 200 away radially. Wherein, the outer diameter of the second end of the riveting part 1 is larger than the outer diameter of the welding part 2.

[0028] Based on the above-described process of the present invention, installation can be achieved using the following method, specifically including the following steps: A first plate 100 is provided, and a rivet is pierced into the first plate 100 along the direction from the first end to the second end; pressure is continuously applied to the rivet, causing the riveting portion 1 of the rivet to embed into the first plate 100, and causing at least a portion of the first plate 100 to enter the anti-dislodgement groove 11 of the riveting sidewall; a second plate 200 is provided, and a non-conductive structural adhesive 300 is coated on the first end face of the second plate 200, and the protruding welding portion 2 of the second end of the rivet is attached to the non-conductive structural adhesive 300; pressure is applied to the first end face of the riveting portion 1, causing the arc surface 21 of the second end face of the welding portion 2 to push the non-conductive structural adhesive 300 radially away and contact the second plate 200; pressure and current are continuously applied to the first end face of the riveting portion 1, causing the welding portion 2 to conduct with the second plate 200 and form a fusion nugget connection.

[0029] In the above steps, the welding part 2 can gradually soften into a molten nugget under extrusion and electric welding. After the welding part 2 becomes conductive with the second plate 200 and forms a molten nugget connection, the second end face of the riveting part 1 fits against the first end face of the second plate 200. That is, in the final stage of the above connection method, when the welding pressure and current are stopped, the second end face of the riveting part 1 and the first end face of the second plate 200 are tightly fitted together. This state marks the completion of the connection process. At this time, the first plate 100 is clamped between the rivet head and the second plate 200, and is fully fixed axially and radially by the anti-disengagement groove 11.

[0030] Of course, the second end face of the riveting part 1 mentioned above is in contact with the first end face of the second plate 200, which means that they are physically adjacent and have a micro gap between them in an annular space 3, which is used to store non-conductive structural adhesive 300 as a medium for contact.

[0031] In the above embodiments, the resistance-welded rivet serves as a connecting medium, used to achieve a dual mechanical and metallurgical connection between the first plate 100 and the second plate 200. The first plate 100 is typically an aluminum alloy plate or a composite material plate, while the second plate 200 is typically a steel plate. That is, the first plate 100 is generally set to be a plate with a lower material strength than the second plate 200, and the connection between the two different plates is achieved by means of a rivet.

[0032] Specifically, an upper weld point 12 is provided at the middle position of the first end face of the riveting part 1 for contacting the upper electrode. A lower weld point 22 is provided on the second end face of the welding part 2 for conducting with the second plate 200 and the lower electrode circuit. The upper weld point 12 and the lower weld point 22 together form the main path for current flow.

[0033] Specifically, please see Figure 5-6The initial state of the non-conductive structural adhesive is as follows: Figure 5 The uniform coating with a certain gentle slope shown is applied to the surface of the second plate 200. Figure 6 In the middle, the arc surface of the welding part 2 presses the non-conductive structural adhesive, causing it to be squeezed away from both sides in the horizontal direction.

[0034] The riveting part 1 serves as the main support structure for the rivet, and its sidewall is radially recessed to form an anti-loosening groove 11. In this embodiment, the anti-loosening groove 11 adopts a flared, tapered anti-loosening groove design. During the process of the resistance-welded rivet piercing the first plate 100, the material of the first plate 100 undergoes plastic deformation and is squeezed into the anti-loosening groove 11 at the root by the mechanical extrusion action of the external mold. The above structural design enables the rivet to be physically locked after riveting, and can withstand a large axial pull-out force, effectively preventing the workpiece from loosening during subsequent transportation and press-fitting production lines.

[0035] Since the surface of the second plate 200 is typically coated with non-conductive structural adhesive, during the initial welding stage, the arc surface 21 gradually expands the contact area through point contact. The resulting pressure gradient can smoothly expel the structural adhesive sandwiched between the arc surface 21 and the second plate 200 radially outward. Compared to traditional pure planar designs, this micro-arc structure ensures direct contact between metals, thereby greatly improving the success rate of welding conductivity and avoiding molten metal spatter or incomplete welding caused by adhesive obstruction. Compared to directly creating a complete large arc surface design at the bottom of the riveting part 1, the raised small arc surface structure of this embodiment can also avoid the situation where the second end face of the riveting part 1 and the second plate 200 are not connected smoothly.

[0036] In other words, in the solution of this invention, the first plate 100 can be fastened by the radially concave anti-loosening groove 11 of the riveting part 1, which has a good anti-loosening effect. Furthermore, the non-conductive structural adhesive 300 is pushed away by the locally set, additionally protruding welding part 2, thereby improving the welding quality. Specifically, the anti-loosening groove 11 set in this invention can achieve a very strong physical anti-loosening effect by utilizing the plastic flow of the material, which is significantly better than the traditional grooveless design. At the same time, with the special structure of the arc surface 21 of the welding part 2 and the design of the lower welding point 22 with a specific micro-arc, the non-conductive structural adhesive 300 can be forcibly discharged under adhesive welding conditions, ensuring stable electrical signal conduction and providing extremely high process stability and sealing protection capabilities in mass automated production.

[0037] In one preferred embodiment, the welding part 2 protrudes outward from the middle position of the second end face of the riveting part 1. The centering design of this embodiment ensures that the current can spread evenly from the center to the outer periphery during the welding process, and also ensures the axial consistency of the mechanical pressure, avoiding the rivet from deflecting during the pressing process.

[0038] Furthermore, the welding portion 2 has a preset axial thickness, so that after welding, the welding portion 2 collapses and deforms axially to form a molten nugget, and just so that the second end face of the riveting portion 1 comes into contact with the second plate 200. During the electric welding stage, the welding portion 2 undergoes controlled plastic collapse deformation under the combined action of high temperature and axial pressure and finally forms a molten nugget. Since the size of the welding portion 2 in this embodiment only occupies a small part of the space at the bottom of the riveting portion 1, it can avoid affecting the fit between the bottom of the riveting portion 1 and the second plate 200 after the molten nugget is formed.

[0039] In the specific design of the welding part 2, the convex curvature of the arc surface 21 of the welding part 2 is set between 0° and 1°. This angle range can form a pressure gradient from the center to the edge when the rivet is pressed down, which can push away the uneven thickness of the non-conductive structural adhesive 300, without causing the initial contact area of ​​the weld to be too small due to excessive curvature, thereby avoiding spatter caused by local overheating.

[0040] Furthermore, after the piercing and riveting is completed with the first plate 100, the first end face of the riveting part 1 remains flush with the first end face of the first plate 100, while the second end face of the riveting part 1 is fitted to the second plate 200 after welding. This dimensional fit ensures a predetermined physical gap between the first plate 100 and the second plate 200, guaranteeing that the main bodies of the first plate 100 and the second plate 200 do not contact each other. Of course, in other embodiments, the spacing can be adjusted as needed.

[0041] In the specific design of the anti-pull-out groove 11, the wall surface of the anti-pull-out groove 11 includes a first inclined wall 111 and a second inclined wall 112 connected from the first end to the second end. The included angle between the first inclined wall 111 and the second inclined wall 112 is set to be neither 0° nor 180°. The non-collinear wall design of this embodiment forms a flared shape. When the material of the first plate 100 flows into this area under the action of the mold, it will generate a multi-directional biting force. Neither the first inclined wall 111 nor the second inclined wall 112 is parallel to the axial direction. Therefore, the pull-out resistance can be improved in both the upper and lower directions, and the processing cost is low.

[0042] Specifically, the present invention also discloses a connector structure, which is a combination structure of the first plate, the second plate, and the resistance-welded rivet in the above structure. The connector includes a resistance-welded rivet and a connection between the first plate 100 and the second plate 200. The riveting part 1 of the resistance-welded rivet is riveted to the first plate 100. The welding part 2 on the middle of one side of the second end of the riveting part 1 of the resistance-welded rivet is welded to the second plate 200. The second end face of the riveting part 1 is provided with non-conductive structural adhesive 300 in the annular space 3 between the periphery of the welding part 2 and the second plate 200. There is no non-conductive structural adhesive 300 at the weld nugget position formed by the welding part 2. The first plate 100 and the second plate 200 are arranged in parallel. The resistance-welded rivet is in a flat state relative to the first plate 100 and the second plate 200.

[0043] Specifically, in terms of size design, the diameter of the lower welding point 22 is set to about half the diameter of the riveting part 1. This ratio ensures that the welding current can be highly concentrated in the central area, thereby generating sufficient heat at the moment of arc initiation. Considering that the surface of the second plate 200 may have flatness deviations, the axial protrusion height of the welding part 2 relative to the second end face of the riveting part 1 is set to be between 0.2mm and 0.3mm to achieve reliable point contact with the substrate of the second plate 200.

[0044] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention specification and drawings are included in the scope of the patent application of the present invention.

[0045] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0046] Although this application has been described by way of examples, those skilled in the art will know that this application has many modifications and variations without departing from the spirit of this application, and it is intended that the appended embodiments include these modifications and variations without departing from this application.

Claims

1. A resistance-welded rivet for connecting a first plate and a second plate, the rivet having a first end and a second end disposed opposite to each other along an axial direction, characterized in that... The resistance welding rivet includes: The riveting part is used for piercing and riveting with the first plate to form an interference fit connection; The welding part protrudes outward from the second end face of the riveting part, and the second end face of the welding part is set as an arc surface. The arc surface is used to contact the second plate before welding so as to push the non-conductive structural adhesive coated on the first end face of the second plate radially away. The outer diameter of the riveted part is larger than the outer diameter of the welded part.

2. The resistance-welded rivet according to claim 1, characterized in that: At least a portion of the sidewall of the riveting part is radially recessed to form an anti-detachment groove, which is used to accommodate at least a portion of the first plate and prevent detachment after the riveting part is riveted to the first plate.

3. The resistance-welded rivet according to claim 1, characterized in that: The welded portion protrudes outward from the middle position of the second end face of the riveted portion.

4. The resistance-welded rivet according to claim 1, characterized in that: An upper weld point is provided at the middle position of the first end face of the riveting part, and a lower weld point is provided at the second end face of the welding part.

5. The resistance-welded rivet according to claim 1, characterized in that: The welded part has a preset axial thickness so that after welding, the welded part collapses and deforms axially to form a weld nugget, and just so that the second end face of the riveted part comes into contact with the second plate.

6. The resistance-welded rivet according to claim 1, characterized in that: The arc of the welded part is set to be between 0° and 1°.

7. The resistance-welded rivet according to claim 1, characterized in that: The riveting part has a preset axial thickness, so that after being riveted to the first plate, the first end face of the riveting part is flush with the first end face of the first plate, the second end face of the riveting part is in contact with the second end face of the second plate, and a preset gap is maintained between the first plate and the second plate.

8. The resistance-welded rivet according to claim 2, characterized in that: The anti-detachment groove includes a first inclined wall and a second inclined wall connected from the first end to the second end, wherein the included angle between the first inclined wall and the second inclined wall is not 0° or 180°.

9. The resistance-welded rivet according to claim 8, characterized in that: Neither the first inclined wall nor the second inclined wall is parallel to the axial direction.

10. The resistance-welded rivet according to claim 1, characterized in that: The outer diameter of the welded part is half the outer diameter of the riveted part, and the outward protrusion of the welded part is between 0.2 mm and 0.3 mm.

11. A connector, characterized in that, The connector includes a resistance-welded rivet, a first plate, and a second plate. The riveting part of the resistance-welded rivet is riveted to the first plate. The welding part on one side of the second end of the riveting part of the resistance-welded rivet is welded to the second plate. Non-conductive structural adhesive is provided in the annular space between the outer periphery of the welding part and the second plate. There is no non-conductive structural adhesive at the weld nugget position formed by the welding part. The first plate and the second plate are arranged in parallel. The resistance-welded rivet is flat relative to the first plate and the second plate.

12. A method for connecting rivets by resistance welding, characterized in that, Includes the following steps: A first plate is provided, and a rivet is pierced through the first plate in a direction from the first end to the second end; Continuously apply pressure to the rivet, causing the rivet's riveting portion to embed into the first plate, and causing at least a portion of the first plate to enter the anti-dislodgement groove of the riveting sidewall; A second plate is provided, and a non-conductive structural adhesive is coated on the first end face of the second plate. The welded part of the second end of the rivet is attached to the non-conductive structural adhesive. Pressure is applied to the first end face of the riveting part, causing the arc surface of the second end face of the welding part to push the non-conductive structural adhesive away radially and into contact with the second plate. Pressure and current are continuously applied to the first end face of the riveting part, so that the welding part is connected to the second plate and forms a weld nugget connection.

13. The method for connecting rivets by resistance riveting according to claim 12, characterized in that: After the step of "continuously applying pressure and current to the first end face of the riveting part so that the welding part is connected to the second plate and forms a fusion nugget connection", the second end face of the riveting part is in contact with the first end face of the second plate.

Images