A spin riveting welding nail and a spin riveting resistance welding device and method thereof

Abstract

The application discloses a spin riveting welding nail and a spin riveting resistance welding device and method thereof, the spin riveting welding nail is vertically arranged between the upper tool head and the upper layer connected component, the lower layer connected component is connected to the bottom side of the upper layer connected component, and the lower electrode is arranged directly below the lower layer connected component. The spin riveting welding nail and the spin riveting resistance welding device can realize the connection between different materials, and can generate metallurgical connection between the spin riveting nail and the lower layer connected component through resistance heating after penetrating the upper layer connected component in the mode of milling and drilling, meanwhile, a mechanical riveting structure is formed between the nail cap and the upper layer connected material, so that the double connection structure of welding and mechanical riveting is considered, and then it is convenient to penetrate higher strength material, the spin riveting welding is not limited by material hardness, and the structure of the spin riveting welding is more stable.

Description

Technical Field

[0001] This invention relates to the field of resistance riveting technology, specifically to a rotary riveting stud and its rotary resistance riveting device and method. Background Technology

[0002] The connection of dissimilar materials in passenger car bodies mainly employs two methods: self-piercing riveting and rotary tapping riveting. Both methods require the rivet to penetrate into the underlying material being connected. However, with the development of ultra-high-strength steel, the strength of steel used in car bodies has gradually increased. When using self-piercing riveting or rotary tapping riveting to connect high-strength, difficult-to-deform materials like ultra-high-strength steel plates, the high deformation resistance of the materials makes it easy for the rivets to bulge or even break. This makes it difficult to penetrate the plate and form an effective mechanical self-locking, thus causing the plate connection to fail.

[0003] Based on the above situation, a resistance riveting welding method has been proposed in China. This method uses a pointed riveting rivet with a rivet head. Pressure is applied to force the tip of the rivet into the upper material to be riveted. After penetrating the upper material, it comes into contact with the lower material to be riveted. Then, an electric current is applied, generating heat at the contact surface between the rivet and the lower material, causing a metallurgical connection between the rivet and the lower material. In this way, the upper material is riveted by the rivet, and a welded metallurgical connection is formed between the lower material and the head of the rivet, thus completing the riveting connection between the upper and lower materials. However, this connection method has a problem: when the upper material is thick, the pointed riveting rivet is not easy to penetrate the upper material. At the same time, when the rivet head is pressed in, the upper material is squeezed to the periphery of the rivet, which causes the upper material around the rivet to bulge.

[0004] In the prior art, according to the riveting machine and its riveting head disclosed in Chinese Patent CN204338778U, its structure includes a connecting part and a rolling head that contacts the rivet. The connecting part is used to connect with the riveting head connector of the riveting machine. The connecting part is fixedly connected to the rolling head, which is a tungsten steel rolling head. The above structure can extend the service life of the rolling head by using tungsten steel with high hardness, thereby increasing the service life of the riveting head. However, the connection part between the riveting head and the riveting machine in the above structure is simple, so the load-bearing capacity is insufficient and it is prone to breakage. In view of the above problems, there is an urgent need for innovative design based on the original riveting resistance welding device. Summary of the Invention

[0005] The purpose of this invention is to provide a riveting stud and a riveting resistance welding device and method thereof, in order to solve the problems mentioned in the background art. In the existing riveting resistance welding device, the riveting stud is not easy to pierce high-strength plates, and when the stud head is pressed into the plate, the connection strength between the riveting stud and the welding device is insufficient and it is easy to break. In addition, after the original rivet is pressed into the plate, the upper material is squeezed to the periphery of the rivet to form a protrusion, which is not conducive to improving the quality of resistance welding.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a riveting resistance welding device, wherein the riveting stud is vertically arranged between the upper tooling head and the upper connected part, and the lower connected part is connected to the bottom side of the upper connected part, and the lower electrode is arranged directly below the lower connected part.

[0007] The above structure allows the riveting stud to be connected to the lower connected parts by resistance welding, and the riveting stud is not easily restricted by the lower connected parts, thus facilitating the connection of higher strength materials. At the same time, while resist welding the materials, a dual connection structure of welding metallurgy and mechanical riveting is formed, which makes the connection strength of riveting resistance welding higher.

[0008] Preferably, the upper tooling head is made of hard alloy steel, and a concave groove is provided in the center of the bottom end of the upper tooling head. A concentric annular heat dissipation groove is also provided at the bottom of the upper tooling head. At the same time, a conductive post is vertically nested in the center of the interior of the upper tooling head. The above structure makes the upper tooling head stronger, can stably match the riveting welding studs to mill and drill the plate, and can accelerate the heat dissipation efficiency of the riveting resistance welding device.

[0009] Preferably, the conductive post is made of copper alloy and has a hollow cooling water channel inside. The above structure facilitates cooling and heat dissipation of the conductive post, thereby improving the service life and quality of the riveting resistance welding device.

[0010] Preferably, the rivet is provided with a head, a cap, and a body in sequence from top to bottom, and the head, cap, and body together form an integrated structure with the rivet. The head and the concave groove are matched in shape, and the head and the bottom side of the upper tooling head are fitted together through the concave groove. The above structure allows the rivet to be firmly fitted at the bottom of the upper tooling head, which makes the rivet pressure strength greater and can prevent the rivet from loosening and breaking.

[0011] Preferably, the nail head is provided with a wedge-shaped notch for rotational drive, and the wedge-shaped notch is formed by the intersection of a first plane and a second plane, and the angle between the first plane and the second plane and the intersection line of the nail head upper surface is 25-80°. The above structure allows the nail head to be more firmly embedded in the bottom of the upper tooling head, so that the wedge-shaped notch is accurately matched in the groove at the bottom of the upper tooling head.

[0012] Preferably, the first plane is perpendicular to the upper surface of the nail head and is used to bear axial torque, and the second plane is inclined downward along the upper surface of the nail head and is used for dynamic engagement. The nail head realizes the rotation drive function through the cooperation of the first plane and the second plane with the concave groove. The above structure enables the upper tooling head to drive the riveting nail to rotate and move synchronously towards the connected part, thereby performing milling and drilling on the connected part.

[0013] Preferably, the nail head is a disc-shaped structure with an indentation towards the nail head, and the nail head is perpendicular to the upper surface of the nail head. It is used to cooperate with the upper tooling head to play a limiting role. The above structure enables the nail head to strengthen the mechanical connection strength of the rivet and weld nail, and effectively prevent the rivet from loosening and falling off.

[0014] Preferably, the nail body has a cylindrical or frustum-shaped structure, and the bottom of the nail body is surrounded by milled grooves. The included angle between the two intersecting planes of the milled grooves is 10-180°, and the included angle between the two intersecting planes of the milled grooves and the plane where the bottom of the nail body is located is 5-90°. The above structure allows the grooves on the nail body to mill and drill holes in the upper connected component, thereby quickly contacting the lower connected component.

[0015] Preferably, the deepest part of the bottom of the milling groove can reach the central axis of the nail body, and the depth of the milling groove gradually becomes shallower from bottom to top. The above structure makes the drilling strength of the milling groove higher, and can drill holes on the surface of the plate more quickly and stably.

[0016] Preferably, the lower electrode is made of copper alloy and has a hollow cooling water channel inside. The above structure enables the lower electrode to be used with a tooling head to form a riveting and welding device, which can then be continuously heated until the welding point cools and solidifies to form a strong riveting and welding structure.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: the riveting welding stud and its riveting resistance welding device, through the riveting welding stud structure with milled grooves, penetrate the upper connected part by milling and drilling, and then, in conjunction with resistance heating, achieve riveting and welding connection between the riveting welding stud and the connected part, so as to facilitate the connection between dissimilar materials. The specific details are as follows:

[0018] 1. The riveting welding stud and its riveting resistance welding device have a structure in which a matching riveting welding stud, a stud head, a first plane and a second plane are embedded in a concave groove at the bottom of the upper tooling head. The wedge-shaped notch formed by the first plane and the second plane complements the protruding shape in the concave groove, thereby firmly fitting the stud head of the riveting welding stud to the bottom end of the upper tooling head, so that the upper tooling head can stably drive the riveting welding stud to achieve the rotation drive function, so as to facilitate high-speed milling and drilling.

[0019] 2. The riveting welding stud and its riveting resistance welding device have a structure with a stud head, a stud body, and a milled groove on the riveting welding stud. The stud head, in conjunction with the tooling head, acts as a limit, making the connection between the riveting welding stud and the connecting part more secure. The riveting welding stud is rotated and pressed down, and then the milled groove on the stud body is used to complete the milling and drilling. Compared with other riveting and welding methods where the riveting welding stud is forced to penetrate the upper connected part, it can avoid the deformation of the upper connected part when it is pressed through, and reduce the internal stress of the upper connected part. At the same time, the method of quickly contacting the lower connected part by milling and drilling saves the original pre-drilling processing steps, so that the rivet is not limited by the size and position of the opening. Attached Figure Description

[0020] Figure 1 This is a front view structural diagram of the present invention;

[0021] Figure 2 This is a schematic diagram of the front cross-sectional structure of the tooling head of the present invention;

[0022] Figure 3 This is a front view schematic diagram of the swivel-riveted welding stud of the present invention;

[0023] Figure 4 This is a schematic diagram of the three-dimensional structure of the nail head of the present invention;

[0024] Figure 5 This is a schematic diagram of the front section of the rivet welding stud of the present invention;

[0025] Figure 6 This is a top view of the nail head structure of the present invention;

[0026] Figure 7 This is a schematic diagram of the three-dimensional structure of the nail body of the present invention;

[0027] Figure 8 This is a schematic diagram of the steps of the riveting resistance welding method of the present invention.

[0028] In the diagram: 1. Upper tooling head; 101. Concave groove; 102. Heat dissipation groove; 103. Conductive post; 2. Screw-on welding stud; 201. Stud head; 201a. First plane; 201b. Second plane; 202. Stud head; 203. Stud body; 203a. Milled groove; 3. Upper connected component; 4. Lower connected component; 5. Lower electrode. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Please see Figure 1-7 The present invention provides a technical solution: a riveting resistance welding device, wherein the riveting welding stud 2 is vertically arranged between the upper tooling head 1 and the upper connected part 3, and the lower connected part 4 is connected to the bottom side of the upper connected part 3, and the lower electrode 5 is arranged directly below the lower connected part 4.

[0031] When using the device, the upper connected part 3 and the lower connected part 4 are overlapped and placed between the upper tooling head 1 and the lower electrode 5. The riveting welding nail 2 is installed in the concave groove 101 on the bottom side of the upper tooling head 1, with the nail body 203 of the riveting welding nail 2 facing the connected plate. Then, the upper tooling head 1 controls the riveting welding nail 2 to move closer to the connected part, while the lower electrode 5 also moves closer to the connected part until it contacts the connected part and stops moving. Then, the lower electrode 5 and the upper tooling head 1 continuously press the riveting welding nail 2.

[0032] When using the device for riveting and welding, specifically, according to Figure 1 , Figure 2 and Figure 3 As shown, the upper tooling head 1 is made of hard alloy steel, and a concave groove 101 is provided in the center of the bottom end of the upper tooling head 1. The riveting welding nail 2 is provided with a nail head 201, a nail cap 202 and a nail body 203 in sequence from top to bottom. The nail head 201, nail cap 202 and nail body 203 together form an integrated structure with the riveting welding nail 2. The external dimensions of the nail head 201 and the concave groove 101 are matched with each other. At the same time, the nail head 201 forms an interlocking structure with the bottom side of the upper tooling head 1 through the concave groove 101. First, the upper tooling head 1 is controlled to rotate, which in turn drives the riveting welding nail 2 that is interlocked at its bottom to rotate in the same direction, and gradually controls the riveting welding nail 2 to approach the upper surface of the upper connected part 3.

[0033] When the nail head 201 rotates at high speed driven by the upper tooling head 1, the nail head 201 can be firmly engaged at the bottom of the upper tooling head 1, and is not prone to shaking or breakage. Specifically, according to Figure 3 , Figure 4 and Figure 6As shown, the nail head 201 is provided with a wedge-shaped notch for rotary drive, and the wedge-shaped notch is formed by the intersection of a first plane 201a and a second plane 201b. The angle between the intersection line of the first plane 201a and the second plane 201b and the upper surface of the nail head 201 is 25-80°. The first plane 201a is perpendicular to the upper surface of the nail head 201 and is used to bear axial torque. The second plane 201b is inclined downward along the upper surface of the nail head 201 and is used for dynamic engagement. The nail head 201 realizes the rotary drive function through the cooperation of the first plane 201a and the second plane 201b with the concave groove 101. The wedge-shaped notch formed by the first plane 201a and the second plane 201b matches the wedge-shaped protrusion inside the concave groove 101, so that the nail head 201 can be firmly and accurately installed on the upper tooling head 1, so as to form a high-strength rotary drive structure.

[0034] When the body 203 of the riveting stud 2 contacts the upper surface of the first plane 201a, the upper tooling head 1 continues to drive the riveting stud 2 downwards. Specifically, according to... Figure 3 , Figure 5 and Figure 7 As shown, the nail body 203 has a cylindrical or frustum-shaped structure, and the bottom of the nail body 203 is surrounded by milled grooves 203a. The included angle between the two intersecting planes of the milled grooves 203a is 10-180°, and the included angle between the two intersecting planes of the milled grooves 203a and the plane where the bottom of the nail body 203 is located is 5-90°. The deepest part of the bottom of the milled grooves 203a can reach the central axis of the nail body 203, and the depth of the milled grooves 203a gradually becomes shallower from bottom to top. At this time, the milled grooves 203a on the nail body 203 will mill and drill holes in the upper connected part 3. The riveting nail 2 continues to move downward until the nail body 203, through the milling and drilling action, mills off the excess material and contacts the upper surface of the lower connected part 4. The length of the nail body 203 is related to the thickness of the upper connected part 3, and the nail body length is ≥ the thickness of the upper connected part.

[0035] When the bottom end of the nail body 203 contacts the upper surface of the lower connected part 4, the lower electrode 5 is energized, thus forming a current path between the lower electrode 5, the lower connected part 4, the riveting nail 2, and the upper tooling head 1, and forming a weld nugget on the contact surface between the riveting nail 2 and the lower connected part 4. Specifically, according to... Figure 1 and Figure 2As shown, the bottom of the upper tooling head 1 is provided with a concentric ring-shaped heat dissipation groove 102. Simultaneously, a conductive post 103 is vertically nested in the center of the upper tooling head 1. The conductive post 103 is made of copper alloy, and its interior is a hollow cooling water channel. The lower electrode 5 is also made of copper alloy, and its interior contains a hollow cooling water channel. The nail head 202 is a disc-shaped structure with its interior recessed towards the nail head 201, and it is perpendicular to the upper surface of the nail head 201. It serves to limit the movement of the upper tooling head 1, allowing for simultaneous rotation of the riveting welding nail 2, or energizing without rotating the riveting welding nail 2. The riveting stud 2 can be rotated only for a short period of time before the power is applied, and then the rotation can be stopped in the later stage of the power application process. Whether to rotate or not can be implemented according to the actual effect after riveting and welding. Different methods can be selected for different materials. During the welding process, the resistance in the circuit generates heat, thereby creating a metallurgical connection between the stud body 203 and the lower connected material 4. At the same time, a mechanical riveting structure is formed between the stud head 202 and the upper connected material 3, so that it can take into account both the welding metallurgy and mechanical riveting dual connection modes. Finally, the lower electrode 5 ends the power application, while the upper tooling head 1 and the lower electrode 5 continue to press the riveting stud 2 until the weld nugget cools and solidifies into a strong riveting structure.

[0036] A method for using a riveting resistance welding device: When using this device, according to... Figure 8 As shown, firstly, the upper tooling head 1 drives the riveting welding nail 2 to approach the stacked upper connected part 3 and lower connected part 4. Then, through the rotation of the riveting welding nail 2, the milling groove 203a on the nail head 201 mills and drills a hole, penetrating the upper connected part 3, and thus contacting the lower connected part 4. At this time, the lower electrode 5 is energized and heated between the upper tooling head 1, so that a weld nugget is formed at the connection point between the nail body 203 of the riveting welding nail 2 and the lower connected part 4. Finally, the weld nugget cools and solidifies to form a strong riveting structure. This is the working principle of the riveting welding nail and its riveting resistance welding device.

[0037] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A riveting resistance welding apparatus, the welding apparatus comprising an upper tooling head (1), an upper connected component (3), a lower connected component (4), and a lower electrode (5), characterized in that, The riveting stud (2) is vertically arranged between the upper tooling head (1) and the upper connected part (3), and the lower connected part (4) is connected to the bottom side of the upper connected part (3), and the lower electrode (5) is arranged directly below the lower connected part (4). The riveting stud (2) is provided with a stud head (201), a stud head (202) and a stud body (203) from top to bottom. The stud head (201), stud head (202) and stud body (203) together form an integrated structure with the riveting stud (2). The external dimensions of the stud head (201) and the concave groove (101) are matched with each other. At the same time, the stud head (201) forms an interlocking structure with the bottom side of the upper tooling head (1) through the concave groove (101). The nail head (201) is provided with a wedge-shaped notch for rotational drive, and the wedge-shaped notch is formed by the intersection of a first plane (201a) and a second plane (201b), and the angle between the first plane (201a) and the second plane (201b) and the line of intersection with the upper surface of the nail head (201) is 25-80°. The first plane (201a) is perpendicular to the upper surface of the nail head (201) and is used to bear axial torque. The second plane (201b) is inclined downward along the upper surface of the nail head (201) and is used for dynamic engagement. The nail head (201) achieves the rotation drive function through the cooperation of the first plane (201a) and the second plane (201b) with the concave groove (101). The nail head (202) is a disc-shaped structure with its interior recessed towards the nail head (201), and the nail head (202) is perpendicular to the upper surface of the nail head (201). It is used to cooperate with the upper tooling head (1) to play a limiting role. The nail body (203) has a cylindrical or frustum-shaped structure, and the bottom of the nail body (203) is surrounded by a milled groove (203a). The included angle between the two intersecting planes of the milled groove (203a) is 1-180°, and the included angle between the two intersecting planes of the milled groove (203a) and the plane where the bottom of the nail body (203) is located is 5-90°.

2. The riveting resistance welding device according to claim 1, characterized in that: The upper tooling head (1) is made of hard alloy steel, and a concave groove (101) is provided at the center of the bottom end of the upper tooling head (1), and a concentric ring-shaped heat dissipation groove (102) is provided at the bottom of the upper tooling head (1). At the same time, a conductive post (103) is vertically nested in the center of the interior of the upper tooling head (1).

3. The riveting resistance welding device according to claim 2, characterized in that: The conductive post (103) is made of copper alloy and has a hollow cooling water channel inside; the lower electrode (5) is made of copper alloy and has a hollow cooling water channel inside.

4. The riveting stud for a riveting resistance welding device according to claim 1, characterized in that: The deepest part of the bottom of the milled groove (203a) can reach the central axis of the nail body (203), and the depth of the milled groove (203a) gradually becomes shallower from bottom to top.

5. A welding method based on the riveting resistance welding device according to claim 1, characterized in that, The steps include: placing the upper connected part (3) and the lower connected part (4) overlapping between the upper tooling head (1) and the lower electrode (5), and installing the riveting nail (2) in the concave groove (101) on the bottom side of the upper tooling head (1), with the nail body (203) of the riveting nail (2) facing the connected plate. Then, the upper tooling head (1) controls the riveting nail (2) to move closer to the connected part, while the lower electrode (5) also moves closer to the connected part until it contacts the connected part and stops moving. Then, the lower electrode (5) and the upper tooling head (1) continuously press the riveting nail (2). Control the upper tooling head (1) to rotate, thereby driving the bottom-fitted riveting nail (2) to rotate in the same direction, and gradually control the riveting nail (2) to approach the upper surface of the upper connected part (3); When the body (203) of the swivel welding stud (2) contacts the upper surface of the first plane (201a), the upper tooling head (1) continues to drive the swivel welding stud (2) to move downward. The milling groove (203a) on the body (203) will mill and drill the upper connected part (3). The swivel welding stud (2) continues to move downward until the body (203) mills away excess material through the milling and drilling action and contacts the upper surface of the lower connected part (4). The length of the body (203) is related to the thickness of the upper connected part (3), and the length of the body is greater than or equal to the thickness of the upper connected part. When the bottom end of the nail body (203) contacts the upper surface of the lower connected part (4), the lower electrode (5) is energized, so that a current path is formed between the lower electrode (5), the lower connected part (4), the riveting nail (2) and the upper tooling head (1), and a weld nugget is formed on the contact surface between the riveting nail (2) and the lower connected part (4). Finally, the lower electrode (5) stops being energized, while the upper tooling head (1) and the lower electrode (5) continue to press the riveting nail (2) until the weld nugget cools and solidifies into a strong riveting weld.

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