A high-efficiency ring groove rivet and riveting method

Abstract

The present invention provides an efficient annular groove rivet and riveting method, comprising: a rivet body, the rivet body comprising a rivet head, an annular groove locking part, a neck portion, and a threaded tail portion connected in sequence, the threaded tail portion being provided with a thread structure, and the cross-sectional area of ​​the neck portion being calculated according to the thread median diameter of the threaded tail portion; and a collar, the inner diameter of the collar being greater than the outer diameter of the annular groove locking part. The present invention has the following beneficial effects: compared with the traditional riveting method of combining a hydraulic station and a rivet gun, the present invention can complete the riveting operation by setting a threaded tail portion and rotating a threaded sleeve with a torque wrench, with high installation efficiency, small installation space, wider application range, and low installation equipment cost.

Description

Technical Field

[0001] The invention belongs to the technical field of riveting, and in particular relates to a high-efficiency ring groove rivet and a riveting method. Background Art

[0002] Ring groove rivets are a new type of riveting structure widely used in the automotive industry, construction field, heavy machinery, aerospace and other scenarios. The rivet consists of two parts, namely the high-strength nail body and the ring. When connecting, both sides of the connected parts are open environments. The high-strength core rod is inserted into the prefabricated hole from one side of the workpiece, and the ring is put on the high-strength core rod from the other side. Under the action of axial tensile force and radial extrusion force, the ring is plastically extruded into the annular groove of the core rod to form a permanent and non-detachable connection.

[0003] Since the riveting of ring groove rivets requires a large tensile load, except for ring groove rivets with a nominal diameter of 6mm, rivets of other specifications need to be assembled through a hydraulic station and a rivet gun.

[0004] The following problems exist in the use of traditional ring groove rivets: First, the installation equipment cost is high. Due to its structural limitations, ring groove rivets are installed with hydraulic rivet guns. The price of a hydraulic station and rivet gun on the market is about 150,000 yuan. If installation points need to be set up on multiple production lines or multiple workstations, the cost will increase exponentially, which is unaffordable for general civilian industrial products. Second, the scope of application is narrow. In some work scenarios, there are high requirements for the portability of installation tools. For example, in the installation of tower structures, photovoltaic bracket structures, railway hanging strings and other scenes that require aerial assembly or on-site assembly, it is obviously impossible to lift the bulky hydraulic station into the air or carry it with you, resulting in the limitation of the scope of application of rivets. Third, the riveting speed is slow and the riveting quality is insufficient. The higher the strain rate of the plastic deformation of the material during the riveting process, the more uniform the plastic deformation of the riveting area, and the less thermal deformation and performance degradation of the material, the better the performance of the riveting point. Traditional ring groove rivets are installed by hydraulic pull rivets. The riveting time usually takes 0.5s-1s, and the material strain rate is low, so there is a lot of room for improvement in riveting quality. Summary of the invention

[0005] In view of this, the present invention aims to provide a high-efficiency ring groove rivet and riveting method, in order to solve at least one of the above-mentioned technical problems.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] A high-efficiency ring groove rivet, comprising:

[0008] A nail body, the nail body comprising a rivet head, a ring groove locking portion, a neck portion, and a threaded tail portion connected in sequence, the threaded tail portion being provided with a thread structure, and the cross-sectional area of ​​the neck portion being calculated according to the thread median diameter of the threaded tail portion;

[0009] The inner diameter of the collar is larger than the outer diameter of the ring groove locking portion.

[0010] Furthermore, the thread structure of the threaded tail portion is an external thread on the outer side wall of the threaded tail portion.

[0011] Furthermore, the thread structure of the thread tail portion is a thread groove, and the thread groove and the thread tail portion are coaxially arranged.

[0012] Furthermore, a lubricating layer is provided on the surface of the thread tail portion.

[0013] Furthermore, the thread structure of the thread tail portion is a multi-thread thread;

[0014] The number of threads in a multithreaded thread is determined by the nominal rivet diameter.

[0015] Furthermore, an anti-slip structure is provided on the supporting surface of the rivet head.

[0016] Furthermore, the minimum diameter of the rivet head bearing surface is calculated based on the thread pitch diameter, and the formula is as follows:

[0017] ;

[0018] in, is the equivalent friction diameter of the rivet head, The thread diameter at the end of the thread. is the thread profile angle, is the pitch of the thread end, is the thread friction coefficient, is the friction coefficient between the rivet support surface and the parts to be connected, is the anti-slip safety factor.

[0019] Furthermore, the rivet head is connected to the annular groove locking portion through a rivet rod.

[0020] A second aspect of the present invention provides an efficient riveting method, comprising the following steps:

[0021] S1. Insert the rivet body through the riveting hole;

[0022] S2. Install the collar on the outer side of the ring groove locking portion of the rivet;

[0023] S3, the threaded sleeve is threadedly connected with the threaded tail of the nail body;

[0024] S4, rotating the threaded sleeve in the tightening direction, the threaded sleeve squeezes the collar to deform the locking ring groove locking part until the broken neck of the nail body breaks;

[0025] The rivet is the high-efficiency ring groove rivet described in one aspect.

[0026] Compared with the prior art, the high-efficiency ring groove rivet and riveting method described in the present invention have the following beneficial effects:

[0027] (1) Compared with the traditional riveting method of combining a hydraulic station and a rivet gun, the high-efficiency ring groove rivet described in the present invention can be riveted by setting a threaded tail and rotating the threaded sleeve with a torque wrench. It has high installation efficiency, small installation space, wider application range, and low installation equipment cost.

[0028] (2) The high-efficiency ring groove rivet described in the present invention increases the diameter of the broken neck, and the preload force of the high-efficiency ring groove rivet that breaks under tensile and torsion loads is consistent with that of national standard products.

[0029] (3) In the high-efficiency riveting method described in the present invention, the thread structure of the thread tail portion adopts a multi-thread design, which can increase the riveting speed.

[0030] (4) The high-efficiency riveting method described in the present invention can complete the riveting operation by rotating the threaded sleeve, thereby improving work efficiency, occupying less space and expanding the scope of application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 A schematic diagram of the three-dimensional structure of the nail body according to an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of a cross-sectional structure of a nail body according to an embodiment of the present invention;

[0034] Figure 3 A schematic cross-sectional view of the use status of the high-efficiency ring groove rivet according to an embodiment of the present invention;

[0035] Figure 4 The figure is a schematic flow chart of the riveting method according to an embodiment of the present invention.

[0036] Description of reference numerals:

[0037] 1. Nail body; 2. Ring; 3. Part to be connected; 4. Threaded sleeve; 101. Rivet head; 102. Nail rod; 103. Ring groove locking part; 104. Broken neck; 105. Threaded tail; 401. Deformation groove. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0041] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0042] like Figure 1-3 As shown, a high-efficiency ring groove rivet comprises:

[0043] The nail body 1 includes a rivet head 101, a ring groove locking portion 103, a neck portion 104, and a threaded tail portion 105 which are connected in sequence. The threaded tail portion 105 is provided with a thread structure. The cross-sectional area of ​​the neck portion 104 is calculated according to the thread median diameter of the threaded tail portion 105.

[0044] The inner diameter of the collar 2 is larger than the outer diameter of the annular groove locking portion 103 .

[0045] The hardness and strength of the collar 2 are respectively lower than the hardness and strength of the nail ring groove locking portion 103 .

[0046] In some embodiments, the thread structure of the thread tail portion 105 is an external thread on the outer wall of the thread tail portion 105. The thread tail portion adopts a metric thread, and other threads such as an imperial thread, an MJ thread, a trapezoidal thread, a rectangular thread, a serrated thread, etc., although the screwing performance and the torque-tensile force conversion relationship are slightly different, the improvement ideas are similar to the calculation method involved in the present invention.

[0047] In other embodiments, the thread structure of the thread tail portion 105 is a thread groove, and the thread groove and the thread tail portion 105 are coaxially arranged.

[0048] A lubricating layer is provided on the surface of the thread tail portion 105 , and the lubricating layer adopts but is not limited to the existing MoS2 coating.

[0049] The thread structure of the thread tail portion 105 is a multi-thread thread;

[0050] The number of threads in a multithreaded thread is determined by the nominal rivet diameter.

[0051] When the number of threads is higher than three, the processing is more difficult, so threads higher than three are not considered. The thread structure of the thread tail adopts a multi-thread design, which can increase the riveting speed.

[0052] Since multi-threaded screw tails increase the rivet assembly torque, for larger rivets, if the required assembly torque is close to the limit of the portable tightening tool, multi-threaded design should not be used. According to calculations, the recommended screw tail threads for different specifications of I-type ring groove rivets are as follows:

[0053] Table 1 Recommended screw tail threads for high-efficiency ring groove rivets of different specifications

[0054] Rivet nominal diameter (mm) Number of screw tail threads 6~10 3 12~14 2 ≥16 1

[0055] The supporting surface of the rivet head is provided with an anti-skid structure, which may be an anti-skid pattern or anti-skid rubber.

[0056] The material of the rivet remains unchanged, and the equivalent uniaxial stress of the high-efficiency ring groove rivet that breaks under tension and torsion load should be equal to the cross-sectional area of ​​the broken neck of the national standard ring groove rivet:

[0057] ;

[0058] In order to ensure the same riveting quality, the riveting loads of the two must be the same, that is, , combined to get:

[0059] ;

[0060] For the same cross-sectional area, the tensile stress Torsional shear stress The relationship satisfies the formula: ;

[0061] When the bolt connection structure is installed by the tightening method, if there is no restriction on the bolt head, the bolt may rotate when tightening the nut, resulting in the inability to complete the assembly. Therefore, an additional wrench is usually required to impose restrictions on the bolt head. The head of the ring groove rivet is a rotationally symmetrical figure, and the rotation direction of the rivet head cannot be restricted during the assembly process. Since the assembly process of ordinary ring groove rivets is a pure tensile assembly, there is no need to consider the problem of rivet rotation. Since the high-efficiency ring groove rivets of this application modify the assembly method to tightening assembly, if the rivet rotation problem occurs, the assembly cannot be completed.

[0062] Friction torque at the rivet head for:

[0063] ;

[0064] Friction torque at the thread taking into account the thread lead angle for:

[0065] :

[0066] The basic conditions for the rivet to not rotate are:

[0067] ;

[0068] The minimum diameter of the rivet head bearing surface is calculated based on the thread pitch diameter, and the formula is as follows:

[0069] ;

[0070] in, is the equivalent friction diameter of the rivet head, The thread diameter at the end of the thread. is the thread profile angle, is the pitch of the thread end, is the thread friction coefficient, is the friction coefficient between the rivet support surface and the parts to be connected, The anti-slip safety factor ranges from 1 to 2.

[0071] The equivalent friction diameter of the rivet head can be simplified as the diameter of the contact area between the rivet head and the parts to be connected.

[0072] Taking the extreme case where the surface of the connected parts is relatively smooth as an example, the friction coefficient between the rivet head and the connected parts is Only 0.08. Take the anti-slip safety factor Assuming that the screw tail is sprayed with MoS2 coating, the friction coefficient The value is 0.11. At this time, the equivalent friction diameter of the rivet head required for some specifications of rivets not to rotate Minimum value and equivalent friction diameter of rivet head of national standard ring groove rivet of the same specification As shown in Table 2.

[0073] Table 2 Minimum friction coefficient of rivet head of some specifications of I-type TP rivets without rotation

[0074] Rivet nominal diameter (mm) d2(mm) μs α(°) P(mm) μw dw,TP(mm)(when SS=1) National standard ring groove rivet dw, Huck (mm) 6 5.35 0.11 30 1 0.08 12.47 13 8 7.188 0.11 30 1.25 0.08 16.39 16 10 9.026 0.11 30 1.5 0.08 20.30 19 12 10.863 0.11 30 1.75 0.08 24.21 22 14 12.701 0.11 30 2 0.08 28.12 25

[0075] According to the calculation results, the friction coefficient between the rivet head 101 and the part to be connected 3 is

[0076] When the diameter is only 0.08, if the rivet head size 101 of the national standard ring groove rivet is still used, except for the rivet with a nominal diameter of 6mm, other models will fail due to rivet rotation.

[0077] The size of the rivet head 101 of the present invention needs to be designed according to a formula, and the head size specified in the national standard ring groove rivet cannot be directly adopted. The equivalent friction diameter of the rivet head 101 is calculated by the thread median diameter of the thread tail 105, which can effectively prevent the rivet from rotating.

[0078] The rivet head 101 is connected to the annular groove locking portion 103 via the rivet rod 102 .

[0079] like Figure 4 As shown, an efficient riveting method comprises the following steps:

[0080] S1, inserting the rivet body 1 through the riveting hole;

[0081] S2, installing the collar 2 on the outer side of the ring groove locking portion 103 of the rivet;

[0082] S3, the threaded sleeve 4 is threadedly connected to the threaded tail portion 105 of the nail body 1;

[0083] S4, the threaded sleeve 4 is rotated in the tightening direction, and the threaded sleeve 4 squeezes the collar 2 to deform the locking ring groove locking portion 103 until the broken neck 104 of the nail body 1 breaks;

[0084] The rivet is the above-mentioned high-efficiency ring groove rivet.

[0085] When the thread structure of the threaded tail portion 105 is an external thread, a threaded hole matching the threaded tail portion 105 is provided in the threaded sleeve 4, and a deformation groove 401 corresponding to the ring 2 is opened at one end of the threaded sleeve 4 near the rivet, and the inner diameter of the deformation groove 401 is smaller than the outer diameter of the ring 2.

[0086] When the thread structure of the threaded tail portion 105 is a thread groove, a stud matching the threaded tail portion 105 is provided in the threaded sleeve 4, and a deformation groove 401 corresponding to the ring 2 is opened at one end of the threaded sleeve 4 near the rivet, and the inner diameter of the deformation groove 401 is smaller than the outer diameter of the ring 2.

[0087] Beneficial effects:

[0088] First, the installation cost of rivets is reduced. National standard ring groove rivets need to be installed using a hydraulic station + rivet gun. According to the purchase price of this unit, the cost of a single installation equipment is about 150,000 yuan. The rivet proposed by the present invention only requires a threaded sleeve 4 during the installation process, which is relatively low in cost. When used with a common 300Nm~500Nm electric tightening gun on the market, the cost of a single installation point is about 400 yuan, which saves 99.7% of the installation cost compared to traditional hydraulic riveting, greatly improving the economy and applicability of ring groove riveting in engineering applications.

[0089] Second, the portability of the installation tools is improved, and they are suitable for different on-site working environments. The national standard ring groove rivets need to be installed using a hydraulic station + rivet gun. According to the parameter information of the equipment purchased by this unit, the weight of the rivet gun is about 3kg, the weight of the hydraulic station is about 100kg, and the weight of a single installation point is about 103kg; the weight of the threaded sleeve 4 of the present invention is about 200g, and the weight of the common 300Nm~500Nm electric tightening gun on the market is about 1kg, and the weight of a single installation point is about 1.2kg. Compared with traditional hydraulic riveting, the weight is reduced by 98.8%, which greatly improves the convenience of ring groove riveting, so that ring groove riveting can be applied to scenes such as on-site assembly and high-altitude assembly.

[0090] Third, the riveting speed is greatly improved, the strain rate is increased, and the quality of the riveting points is improved. When using a traditional hydraulic riveting gun for riveting, the riveting time is about 0.5s or more. The riveting time of the high-efficiency ring groove rivet in the present invention is 0.136s, and the riveting time of the three-thread screw tail TP rivet is 0.0454s. The riveting time is shortened by 72.8% to 90.92%, and the riveting speed is increased by about 4 to 10 times. The riveting speed is greatly improved, and the quality of the riveting points is improved simultaneously.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

[0092] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-efficiency ring groove rivet, characterized in that: include: A nail body (1), the nail body (1) comprising a rivet head (101), a ring groove locking portion (103), a neck portion (104), and a threaded tail portion (105) connected in sequence, the threaded tail portion (105) being provided with a thread structure, and the cross-sectional area of ​​the neck portion (104) being calculated based on the thread median diameter of the threaded tail portion (105); A collar (2), wherein the inner diameter of the collar (2) is larger than the outer diameter of the annular groove locking portion (103); The minimum diameter of the support surface of the rivet head (101) is calculated based on the thread pitch diameter, and the formula is as follows: ； in, is the equivalent friction diameter of the rivet head (101), is the thread pitch diameter of the thread end (105), is the thread profile angle, is the pitch of the thread end (105), is the thread friction coefficient, is the friction coefficient between the rivet support surface and the parts to be connected, is the anti-slip safety factor.

2. A high-efficiency ring groove rivet according to claim 1, characterized in that: The thread structure of the threaded tail portion (105) is an external thread on the outer side wall of the threaded tail portion (105).

3. The high-efficiency ring groove rivet according to claim 1, characterized in that: The thread structure of the threaded tail portion (105) is a thread groove, and the thread groove and the threaded tail portion (105) are arranged coaxially.

4. The high-efficiency ring groove rivet according to claim 1, characterized in that: A lubricating layer is provided on the surface of the thread tail portion (105).

5. The high-efficiency ring groove rivet according to claim 1, characterized in that: The thread structure of the thread tail portion (105) is a multi-thread thread; The number of threads in a multithreaded thread is determined by the nominal rivet diameter.

6. The high-efficiency ring groove rivet according to claim 1, characterized in that: An anti-slip structure is provided on the supporting surface of the rivet head (101).

7. The high-efficiency ring groove rivet according to claim 1, characterized in that: The rivet head (101) is connected to the annular groove locking portion (103) via a rivet rod (102).

8. An efficient riveting method, characterized in that: The following steps are involved: S1, inserting the rivet body (1) through the riveting hole; S2, installing the collar (2) on the outer side of the annular groove locking portion (103) of the rivet; S3, the threaded sleeve (4) is threadedly connected to the threaded tail portion (105) of the nail body (1); S4, the threaded sleeve (4) is rotated in the tightening direction, and the threaded sleeve (4) squeezes the collar (2) to deform the locking ring groove locking portion (103), until the broken neck (104) of the nail body (1) is broken; The rivet is a high-efficiency ring groove rivet as described in any one of claims 1-7.

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