Aluminum nut for self-piercing riveting of aluminum sheet metal

Abstract

The utility model discloses an aluminum sheet metal self-piercing riveting aluminum nut, which relates to the technical field of aluminum nuts, and comprises a riveting aluminum nut, the riveting aluminum nut consists of a flange and trapezoidal teeth, the trapezoidal teeth are circumferentially distributed on the circumferential surface of the flange at equal intervals, the circumferential surface of the lower end of the flange is provided with a groove, and the lower end of the flange is provided with a through hole. According to the novel riveting aluminum nut, the structure of the trapezoidal teeth in the riveting aluminum nut is optimized, the structural strength of the single tooth is improved, guarantee is provided for achieving self-piercing riveting and riveting performance, the riveting structure and a riveting die of a product are matched, holes do not need to be formed in the lower end face of an aluminum metal plate, and the riveting quality is improved. The riveting aluminum nut is directly riveted in a self-puncturing mode to be connected with the aluminum metal plate, the problem that the matching precision of a riveting area of the riveting aluminum nut and the hole diameter of an open hole is poor is solved, the riveting die is provided with a cutting boss, and the fine boss height is amp; the diameter design ensures that the aluminum metal plate is effectively sheared without burrs, meanwhile, the nut riveting containing groove formed in the aluminum metal plate is filled with materials, and the riveting performance is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of aluminum nuts, in particular to an aluminum nut for self-piercing riveting of aluminum sheet metal. Background Art

[0002] Lightweighting is an important development trend in the automotive industry. Aluminum alloys are widely used in automobiles, and a large number of steel-aluminum dissimilar material connections and aluminum-aluminum connections appear on the body of the car. Traditional welding cannot be applied or the welding effect is poor. Riveting is usually used to achieve the above connection. Compression rivet nuts are a very important connection method used on sheet metal parts. At present, compression rivet nuts are basically made of carbon steel and electroplated to meet the above connection. However, even if the steel compression rivet nuts are treated with surface protection, potential corrosion cannot be avoided when connected with aluminum sheet metal; in addition, due to the different thermal expansion coefficients of steel and aluminum, the riveting points of aluminum plates connected with steel compression rivet nuts may be affected by temperature changes, which may cause connection failure and create safety hazards; at the same time, steel compression rivet nuts do not meet the design principles of lightweighting, and the aluminum compression rivet nuts seen on the market, because their structure and materials are not enough to meet the self-piercing riveting, the sheet metal needs to be opened, which makes the matching requirements between the sheet metal and the nut riveting area extremely demanding, otherwise it is easy to cause insufficient riveting performance. Utility Model Content

[0003] 1. Technical issues to be solved

[0004] In view of the deficiencies in the prior art, the utility model provides an aluminum nut for self-piercing riveting of aluminum sheet metal, which solves the problem of aluminum self-rivet nuts seen on the market. Since their structure and materials are not sufficient to meet the requirements of self-piercing riveting, holes need to be opened in the sheet metal, which results in extremely stringent matching requirements between the sheet metal and the nut riveting area, otherwise it is easy to cause technical problems such as insufficient riveting performance.

[0005] (II) Technical solution

[0006] In order to achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] A self-piercing riveted aluminum nut for aluminum sheet metal includes a riveted aluminum nut, which is composed of a flange and trapezoidal teeth. The trapezoidal teeth are equidistantly distributed on the circumferential surface of the flange. A groove is provided on the circumferential surface of the lower end of the flange. A marking line is provided on the circumferential inner surface of the flange. A threaded groove is provided inside the flange. Aluminum sheet metal is provided on the flange.

[0008] Preferably, the riveted aluminum nut is clamped in and matched with the aluminum sheet metal, and a riveting die is provided at the lower end of the aluminum sheet metal.

[0009] Preferably, a material cutting hole is provided through the middle of the riveting die, and a material cutting boss is provided on the riveting die, and the material cutting boss is used to cut the waste material of the riveting on the aluminum sheet metal.

[0010] (III) Beneficial effects

[0011] 1. The processing efficiency of the riveted aluminum nut in the present invention is improved by more than 100 times, and the material utilization rate is increased by more than 50%. The self-developed high-strength aluminum alloy wire is used to realize the cold heading of the riveted aluminum nut. After aging treatment, it reaches ultra-high strength and hardness, which provides a guarantee for the self-piercing riveting of common aluminum sheet metal (6000 series); and the structure of the trapezoidal teeth in the riveted aluminum nut is optimized to improve the structural strength of the single tooth, which provides a guarantee for the self-piercing riveting and riveting performance. With the riveting structure and riveting die of the product, there is no need to open a hole on the lower end face of the aluminum sheet metal. The riveted aluminum nut can be directly connected to the aluminum sheet metal by self-piercing riveting, which solves the anxiety of poor matching accuracy between the riveting area of ​​the riveted aluminum nut and the aperture of the opening. The riveting die is provided with a cutting boss. The fine boss height & diameter design ensures that the aluminum sheet metal is effectively sheared without burrs, and at the same time, the material is prompted to fill the nut riveting groove opened by the aluminum sheet metal to ensure the riveting performance.

[0012] Second, the new invention has a marking line marked on the inner wall of the flange, so that when the riveted aluminum nut needs to be disassembled, the lower end of the marking line can be grinded, and the groove opened at the lower end of the flange can be completely grinded off, thereby facilitating the removal of the riveted aluminum nut from the aluminum sheet metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the utility model in conjunction with the accompanying drawings.

[0014] Figure 1 It is a structural diagram of the entire utility model;

[0015] Figure 2 This is a structural diagram of the aluminum sheet metal of the utility model;

[0016] Figure 3 This is a structural diagram of the riveted aluminum nut of the utility model;

[0017] Figure 4 This is a structural diagram of a riveted aluminum nut of the same type as the utility model.

[0018] Legend: 11. Riveted aluminum nut; 12. Flange; 13. Trapezoidal teeth; 15. Marking line; 16. Groove; 21. Aluminum sheet metal; 22. Riveting die; 23. Cutting boss. DETAILED DESCRIPTION

[0019] The embodiment of the present application effectively solves the problem of aluminum pressure rivet nuts seen on the market by providing an aluminum nut for self-piercing riveting of aluminum sheet metal. Since the structure and material of the aluminum nut are not sufficient to meet the requirements of self-piercing riveting, holes need to be made in the sheet metal, which results in extremely stringent requirements for matching the riveting area between the sheet metal and the nut, otherwise it is easy to cause insufficient riveting performance. The present invention optimizes the structure of the trapezoidal teeth in the riveted aluminum nut, improves the structural strength of the single tooth, and provides a guarantee for achieving self-piercing riveting and riveting performance. In combination with the riveting structure and riveting die of the product, there is no need to make a hole on the lower end face of the aluminum sheet metal, and the riveted aluminum nut can be directly connected to the aluminum sheet metal by self-piercing riveting, which solves the problem of poor matching accuracy between the riveting area of ​​the riveted aluminum nut and the aperture of the hole. The riveting die is provided with a cutting boss, and the fine boss height & diameter design ensures that the aluminum sheet metal is effectively sheared without burrs, and at the same time encourages the material to fill the nut riveting groove opened in the aluminum sheet metal to ensure riveting performance.

[0020] Example

[0021] like Figure 1 , Figure 2 and Figure 3 As shown, the technical solution in the embodiment of the present application is to effectively solve the problem that the aluminum self-clinching nut seen on the market has a structure and material that are not sufficient to meet the requirements of self-piercing riveting, and the sheet metal needs to be opened, which results in extremely demanding matching requirements between the sheet metal and the nut riveting area, otherwise it is easy to cause the technical problem of insufficient riveting performance. The overall idea is as follows:

[0022] In view of the problems existing in the prior art, the utility model provides an aluminum nut for self-piercing riveting of aluminum sheet metal, including a riveted aluminum nut 11, which is composed of a flange 12 and trapezoidal teeth 13. The trapezoidal teeth 13 are equidistantly distributed on the circumferential surface of the flange 12. A groove 16 is provided on the circumferential surface of the lower end of the flange 12. The trapezoidal teeth 13 in the riveted aluminum nut 11 are used to improve the strength of a single tooth. The trapezoidal teeth 13 and the groove 16 provided at the lower end of the riveted aluminum nut 11 are directly cold-forged without the need for additional machining. The riveted aluminum nut 11 cooperates with a rivet die 22 to directly self-pierce and rivet to achieve connection with the aluminum sheet metal 21. , which solves the anxiety of poor matching accuracy between the riveting area and the aperture of the opening of the riveted aluminum nut 11; the rivet die 22 is provided with a cutting boss 23, and the fine boss height & diameter design ensures that the aluminum sheet metal 21 is effectively sheared without burrs, and at the same time prompts the material to fill the nut riveting groove 24 opened by the aluminum sheet metal 21 to ensure the riveting performance. The material of the riveted aluminum nut 11 is selected from high-strength aluminum alloy (such as CN110066931B disclosed in Chinese patent). After annealing treatment, the cold heading of the riveted aluminum nut 11 can be directly realized, and then after multi-stage solid solution + artificial aging treatment, the hardness can reach 170HV, which meets the self-piercing riveting requirements.

[0023] The inner surface of the circumference of the flange 12 is provided with a marking line 15, the interior of the flange 12 is provided with a thread groove, the flange 12 is provided with an aluminum sheet metal 21, and the riveted aluminum nut 11 is clamped in the aluminum sheet metal 21 and adapted. To ensure that the riveted aluminum nut 11 realizes self-piercing riveting with the aluminum sheet metal 21, the ultra-high strength and hardness of the riveted aluminum nut 11 are required to be significantly higher than the aluminum sheet metal 21, so as to ensure that the trapezoidal teeth 13 and the grooves 16 in the riveting area of ​​the riveted aluminum nut 11 are not deformed during riveting, and the aluminum sheet metal 21 is effectively self-pierced and cut. The mass percentage of each component of the riveted aluminum nut 11 in the device is The ratio is: 2-6wt% Zn, 0.2-6wt% Mg, 0.2-3wt% Mn, 0.2-3wt% Cu, 0.1-2wt% Sc, 0.1-2wt% Yb, 0.1-1wt% Tb, 0.2-2wt% Zr, and the balance is Al. The alloy is subjected to a double-stage homogenization treatment, firstly homogenized at 350-460°C for 4-36h, and then homogenized at 470-510°C for 1h-20h. The aluminum material after homogenization treatment meets the requirement of cold forging 1 / 4 without cracking, thereby ensuring cold heading forming. Then the alloy wire is cold headed, and the riveted aluminum nut 11 is cold headed by a multi-station cold heading machine. The flange 12, trapezoidal teeth 13 and grooves 16 are all cold headed. The cold headed blank is degreased and cleaned, and then a double-stage aging treatment is performed, first at 70-120°C for 4-36h, and then at 130-210°C for 1h-36h, to meet the yield strength of the riveted aluminum nut 11 of more than 450MPa and the hardness of more than 170HV, and finally the required high-strength riveted aluminum nut 11 is obtained.

[0024] A rivet die 22 is provided at the lower end of the aluminum sheet metal 21, a feed hole is provided through the middle of the rivet die 22, a cutting boss 23 is provided on the rivet die 22, and the cutting boss 23 is used to cut the waste riveted on the aluminum sheet metal 21. The processing efficiency of the riveted aluminum nut 11 in the new type is improved by more than 100 times, and the material utilization rate is improved by more than 50%. The self-developed high-strength aluminum alloy wire is used to realize the cold heading forming of the riveted aluminum nut 11, and after aging treatment, it reaches ultra-high strength and hardness, which provides a guarantee for the self-piercing riveting of common aluminum sheet metal 21 (6000 series), and optimizes the structure of the trapezoidal teeth 13 in the riveted aluminum nut 11, improves the structural strength of the single tooth, and provides a guarantee for the self-piercing riveting and riveting performance. With the product riveting structure and the rivet die 22, the aluminum There is no need to open a hole on the lower end surface of the sheet metal 21, and the riveted aluminum nut 11 can be directly connected to the aluminum sheet metal 21 by self-piercing riveting, which solves the anxiety of poor matching accuracy between the riveting area of ​​the riveted aluminum nut 11 and the aperture of the opening. The rivet die 22 is provided with a cutting boss 23. The fine boss height & diameter design ensures that the aluminum sheet metal 21 is effectively sheared without burrs, and at the same time prompts the material to fill the nut riveting groove 24 opened on the aluminum sheet metal 21 to ensure the riveting performance. The new model uses a marking line 15 marked on the inner wall of the flange 12, so that when the riveted aluminum nut 11 needs to be disassembled, the lower end position of the marking line 15 can be polished, which can just completely grind off the groove 16 opened at the lower end of the flange 12, thereby facilitating the removal of the riveted aluminum nut 11 from the aluminum sheet metal 21.

[0025] The shapes of riveted aluminum nuts are of various types, such as Figure 4 The shapes in are all the same type of structures in this application document.

[0026] Working principle:

[0027] In the first step, the trapezoidal teeth 13 in the riveted aluminum nut 11 are to improve the strength of a single tooth. The trapezoidal teeth 13 and the grooves 16 opened at the lower end of the riveted aluminum nut 11 are directly cold-forged without additional machining. The riveted aluminum nut 11 cooperates with the rivet die 22 to directly self-pierce and rivet to achieve connection with the aluminum sheet metal 21, which solves the anxiety of poor matching accuracy between the riveting area of ​​the riveted aluminum nut 11 and the aperture of the opening; the rivet die 22 is provided with a cutting boss 23, and the fine boss height & diameter design ensures that the aluminum sheet metal 21 is effectively sheared without burrs, and at the same time, the material is prompted to fill the nut riveting groove 24 opened by the aluminum sheet metal 21 to ensure the riveting performance. The material of the riveted aluminum nut 11 is selected from high-strength aluminum alloy (such as CN110066931B disclosed in Chinese patent). After annealing, the cold forging of the riveted aluminum nut 11 can be directly realized, and then after multi-stage solution + artificial aging treatment, the hardness can reach 170HV, which meets the self-piercing riveting requirements.

[0028] In the second step, to ensure that the riveted aluminum nut 11 realizes self-piercing riveting with the aluminum sheet metal 21, the ultra-high strength and hardness of the riveted aluminum nut 11 must be significantly higher than that of the aluminum sheet metal 21, so as to ensure that the trapezoidal teeth 13 and the grooves 16 in the riveting area of ​​the riveted aluminum nut 11 do not deform during riveting, and the aluminum sheet metal 21 is effectively self-pierced and cut. The mass percentage of each component of the riveted aluminum nut 11 in the device is: 2-6wt% Zn, 0.2-6wt% Mg, 0.2-3w t% Mn, 0.2-3wt% Cu, 0.1-2wt% Sc, 0.1-2wt% Yb, 0.1-1wt% Tb, 0.2-2wt% Zr, and the balance is Al. The alloy is subjected to a double-stage homogenization treatment, firstly homogenized at 350-460°C for 4-36h, and then homogenized at 470-510°C for 1h-20h. The aluminum material after homogenization treatment meets the requirement of cold forging 1 / 4 without cracking, thereby ensuring cold heading forming. Then the alloy wire is cold headed, and the riveted aluminum nut 11 is cold headed by a multi-station cold heading machine. The flange 12, trapezoidal teeth 13 and grooves 16 are all cold headed. The cold headed blank is degreased and cleaned, and then a double-stage aging treatment is performed, first at 70-120°C for 4-36h, and then at 130-210°C for 1h-36h, to meet the yield strength of the riveted aluminum nut 11 of more than 450MPa and the hardness of more than 170HV, and finally the required high-strength riveted aluminum nut 11 is obtained.

[0029] The third step is that the processing efficiency of the riveted aluminum nut 11 in the new type is improved by more than 100 times, and the material utilization rate is increased by more than 50%. The self-developed high-strength aluminum alloy wire is used to realize the cold heading of the riveted aluminum nut 11. After aging treatment, it reaches ultra-high strength and hardness, which provides a guarantee for the self-piercing riveting of common aluminum sheet metal 21 (6000 series). In addition, the structure of the trapezoidal teeth 13 in the riveted aluminum nut 11 is optimized to improve the structural strength of the single tooth, which provides a guarantee for the self-piercing riveting and riveting performance. With the product riveting structure and the riveting die 22, the lower end surface of the aluminum sheet metal 21 does not need to be opened, and the riveted aluminum nut 11 can directly self-pierce the riveted aluminum nut 11 to achieve the self-piercing riveting with the aluminum sheet metal. The connection of the aluminum sheet metal 21 solves the anxiety of poor matching accuracy between the riveting area of ​​the riveted aluminum nut 11 and the aperture of the opening. The riveting die 22 is provided with a cutting boss 23. The fine boss height & diameter design ensures that the aluminum sheet metal 21 is effectively sheared without burrs, and at the same time prompts the material to fill the nut riveting groove 24 opened on the aluminum sheet metal 21 to ensure the riveting performance. The new type uses a marking line 15 marked on the inner wall of the flange 12, so that when the riveted aluminum nut 11 needs to be disassembled, the lower end position of the marking line 15 can be grinded, which can just grind off the groove 16 opened at the lower end of the flange 12, thereby facilitating the removal of the riveted aluminum nut 11 from the aluminum sheet metal 21.

[0030] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present invention.

Claims

1. An aluminum nut for self-piercing riveting of aluminum sheet metal, comprising a riveted aluminum nut (11), characterized in that: The riveted aluminum nut (11) is composed of a flange (12) and trapezoidal teeth (13), wherein the trapezoidal teeth (13) are equidistantly distributed on the circumferential surface of the flange (12), a groove (16) is provided on the circumferential surface of the lower end of the flange (12), a marking line (15) is provided on the circumferential inner surface of the flange (12), and a thread groove is provided inside the flange (12); Wherein, the flange (12) is provided with an aluminum sheet metal (21).

2. The aluminum nut for self-piercing riveting of aluminum sheet metal according to claim 1, characterized in that: The riveted aluminum nut (11) is clamped in the aluminum sheet metal (21) and is compatible with it.

3. The aluminum nut for self-piercing riveting of aluminum sheet metal according to claim 2, characterized in that: A riveting die (22) is provided at the lower end of the aluminum sheet metal (21).

4. The aluminum nut for self-piercing riveting of aluminum sheet metal according to claim 3, characterized in that: A material discharge hole is provided through the middle of the riveting die (22).

5. The aluminum nut for self-piercing riveting of aluminum sheet metal according to claim 4, characterized in that: The riveting die (22) is provided with a material cutting boss (23).

6. The aluminum nut for self-piercing riveting of aluminum sheet metal according to claim 5, characterized in that: The cutting boss (23) is used for cutting the riveted waste on the aluminum sheet metal (21).

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