Threaded connecting piece and threaded connecting assembly
By designing the first transition connection section, the first arc-shaped section and the second transition connection section on the cross section of the thread groove, the problems of poor thread connection strength and small application range are solved, and a tighter and stronger thread connection is achieved.
Patent Information
- Application Number
- CN202422217741.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-10
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-09-10
AI Technical Summary
In the prior art, the strength of the threaded connection is poor and the scope of application is small, mainly because the trapezoidal structure corners of the internal thread and the external thread are easily interfered, resulting in a lack of tight connection.
The cross-sectional shape of the designed thread groove includes a first transition connection section, a first arc-shaped section and a second transition connection section. The radius of the first arc-shaped section is related to the thread pitch, with a range of 0.15P-0.22P, ensuring smoothness at the connection, avoiding corner interference, and improving strength.
Through the design of smooth connection, the interference between the thread groove and other thread corners is avoided, the tightness and strength of the thread connection is improved, and the application range of threaded connections is expanded.
Smart Images
Figure CN223062852U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the technical field of threaded connections, and particularly relates to a threaded connector and a threaded connection assembly. Background Art
[0002] Threaded connection is a common connection method in industry. Specifically, a threaded connection assembly includes a first threaded connector and a second threaded connector. The first threaded connector is provided with an external thread, the second threaded connector is provided with a threaded hole, and an internal thread is provided in the threaded hole. The internal thread cooperates with the external thread.
[0003] In the related art, as shown in Figure 1 the internal thread and the external thread generally include multiple turns of thread protrusions. A thread groove is formed between two adjacent turns of thread protrusions. The cross-sectional shape of the thread groove in the axial direction of the internal thread or the external thread is a trapezoidal structure. The trapezoidal structure of the internal thread cooperates with the trapezoidal structure of the external thread. In this way, the matching degree requirement for the corners of the trapezoidal structure of the internal thread and the corners of the trapezoidal structure of the external thread is relatively high, so that the corners of the trapezoidal structure of the internal thread are prone to interference with the corners of the trapezoidal structure of the external thread, resulting in insufficient tightness of the threaded connection and poor strength of the threaded connection. Utility Model Content
[0004] The purpose of the embodiments of this application is to provide a threaded connector and a threaded connection assembly, which can solve the problem of poor strength of threaded connection in the related art.
[0005] In a first aspect, the embodiments of this application provide a threaded connector, including a connection body. The connection body is provided with a thread. The thread includes multiple turns of thread protrusions. A thread groove is formed between two adjacent turns of the thread protrusions. In the axial direction of the thread, the cross-sectional shape of the thread groove includes a first transition connection section, a first arc section, and a second transition connection section. The two ends of the first arc section are respectively connected to the first transition connection section and the second transition connection section.
[0006] The radius R of the first arc section is related to the pitch P of the thread, and the radius R of the first arc section = 0.15P - 0.22P.
[0007] In a second aspect, the embodiments of this application further provide a threaded connection assembly, including a connected first threaded connector and a second threaded connector. At least one of the first threaded connector and the second threaded connector is the above-mentioned threaded connector.
[0008] In the embodiments of the present application, the cross-sectional shape of the thread groove includes a first arc segment. The first arc segment is smoothly connected to the first transition connection segment, and the first arc segment is also smoothly connected to the second transition connection segment, so that the corner positions at the joints of the thread groove are smoothly connected. In this way, when the threaded connection member is connected to other threaded structures, the thread groove is not easily interfered with the corner positions of other threads, which is beneficial to making the threaded connection tighter and improving the strength of the threaded connection. Moreover, the radius dimension of the first arc segment is related to the pitch of the thread. The radius of the first arc segment is not too large, effectively avoiding interference between the thread groove and the corner positions of other threads, and the radius of the first arc segment is not too small to avoid affecting the strength of the threaded connection member. Description of the Drawings
[0009] Figure 1 is a connection schematic diagram of a threaded connection assembly disclosed in the related art;
[0010] Figure 2 is a cross-sectional view of a threaded connection member disclosed in an embodiment of the present application;
[0011] Figure 3 is a cross-sectional view of a threaded connection member disclosed in another embodiment of the present application;
[0012] Figure 4 is a connection schematic diagram of a threaded connection member with an external thread in an embodiment of the present application and a threaded connection member in the related art;
[0013] Figure 5 is a connection schematic diagram of a threaded connection member with an internal thread in an embodiment of the present application and a threaded connection member in the related art;
[0014] Figure 6 is a connection schematic diagram of a threaded connection assembly disclosed in an embodiment of the present application;
[0015] Figure 7 is a connection schematic diagram of a threaded connection assembly disclosed in another embodiment of the present application;
[0016] Figure 8 is a connection schematic diagram of a threaded connection member in an embodiment of the present application and a threaded connection member in the related art when R is relatively large;
[0017] Figure 9 is a connection schematic diagram of a threaded connection member in an embodiment of the present application and a threaded connection member in the related art when R is relatively small;
[0018] Figure 10 is a simulation schematic diagram of the stresses received by a threaded connection member (when R = 0.15P) in an embodiment of the present application and a threaded connection member in the related art.
[0019] Description of the Reference Numerals:
[0020] 100 - Connecting body,
[0021] 110 - First threaded connector, 111 - External thread,
[0022] 120 - Second threaded connector, 121 - Internal thread,
[0023] 200 - Threaded protrusion, 210 - Third transition connection section, 220 - Second arc section,
[0024] 300 - Threaded groove, 310 - First transition connection section, 320 - First arc section, 330 - Second transition connection section. Detailed implementation mode
[0025] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.
[0026] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same type, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / ", generally represents an "or" relationship between the associated objects before and after.
[0027] In the related art, referring to Figure 1 As shown, the threaded connection assembly includes a first threaded connector and a second threaded connector. The first threaded connector is provided with an internal thread, and the second threaded connector is provided with an external thread. Both the internal thread and the external thread include multiple turns of threaded protrusions. A threaded groove is formed between two adjacent turns of threaded protrusions. The threaded protrusions of the internal thread cooperate with the threaded grooves of the external thread, and the threaded grooves of the internal thread cooperate with the threaded protrusions of the external thread. Moreover, the shapes of the cross-sections of the threaded grooves and the threaded protrusions in the axial direction of the internal thread or the external thread are both trapezoidal structures, that is to say, the shape of the cross-section includes three straight-line connection sections connected in sequence.
[0028] In this way, the matching degree requirements for the corners of the trapezoidal structure of the internal thread and the corners of the trapezoidal structure of the external thread are relatively high, making it easy for the corner positions of the trapezoidal structure of the internal thread to interfere with the corner positions of the trapezoidal structure of the external thread, resulting in insufficient tightness of the thread connection and poor strength of the thread connection. Moreover, the internal thread with a trapezoidal cross-section can only be matched with the external thread with a trapezoidal cross-section, making the application of the thread connection components relatively single and the applicable range relatively small.
[0029] Based on this, the embodiments of the present application relate to a thread connection component and a thread connection assembly to solve the problems of relatively poor thread connection strength and relatively small applicable range of the thread connection components.
[0030] The following will combine the accompanying drawings and use specific embodiments and their application scenarios to describe in detail the thread connection component and the thread connection assembly provided by the embodiments of the present application.
[0031] Please refer to Figures 2 - 10 As shown, the thread connection component disclosed in the embodiments of the present application includes a connection body 100. The connection body 100 is provided with threads, and the thread connection component is connected to other components through the threads. Optionally, the thread connection component can be a flange, a control valve, a connecting pipe fitting, etc. The embodiments of the present application do not limit the specific structure and type of the thread connection component. The threads here can be external threads 111 or internal threads 121.
[0032] Refer to Figure 2 and Figure 3 As shown, the thread includes multiple turns of thread protrusions 200. A thread groove 300 is formed between two adjacent turns of thread protrusions 200, that is, a thread groove 300 is respectively formed between any two adjacent turns of thread protrusions 200. The thread has multiple turns of thread protrusions 200 and also has multiple thread grooves 300. In the axial direction of the thread, that is, Figure 2 and Figure 3 the direction shown by the center lines in, the cross-sectional shape of the thread groove 300 includes a first transition connection section 310, a first arc section 320, and a second transition connection section 330. The two ends of the first arc section 320 are respectively connected to the first transition connection section 310 and the second transition connection section 330. That is to say, the first transition connection section 310, the first arc section 320, and the second transition connection section 330 are connected in sequence. The first transition connection section 310 and the second transition connection section 330 are located on the groove side walls of the thread groove 300, the first arc section 320 is located on the groove bottom wall of the thread groove 300, and the first transition connection section 310 and the second transition connection section 330 are respectively part of the cross-sections of two adjacent thread protrusions 200.
[0033] The radius R of the first arc segment 320 is related to the pitch P of the thread, and the radius R of the first arc segment 320 = 0.15P - 0.22P. It should be noted that the pitch P refers to the distance between the same positions of two adjacent thread protrusions 200 in the axial direction of the thread, that is, the distance between the same positions of two adjacent thread grooves 300 in the axial direction of the thread. Further, it can be understood as the distance between the first ends of two adjacent first transition connection segments 310 in the axial direction of the thread.
[0034] In an embodiment where the radius R of the first arc segment 320 is greater than 0.22P, refer to Figure 8 As shown, when the threaded connector is mated with the threaded structure in the related art, since the connection between the first arc segment 320 and the first transition connection and the connection between the first arc segment 320 and the second transition connection segment 330 are relatively smooth, these two connection positions are prone to interference with the corners of the existing threaded structure and cannot be stably connected. Therefore, the radius R of the first arc segment 320 cannot be too large.
[0035] In an embodiment where the radius R of the first arc segment 320 is less than 0.15P, refer to Figure 9 As shown, it will undoubtedly extend the lengths of the first transition connection segment 310 and the second transition connection segment 330, making the thread groove 300 deeper. Then, more material needs to be removed from the threaded connector, resulting in a weakened strength of the threaded connector. Therefore, the radius R of the first arc segment 320 cannot be too small.
[0036] Optionally, the radius R of the first arc segment 320 = 0.15P. Refer to the simulation schematic diagram shown in Figure 10 As shown, at point A is the threaded structure in the related art, and at point B is the threaded structure disclosed in the embodiment of the present application. Under the same load condition, the root stress at point A is 963 MPa, and the root stress at point B is 642 MPa. Therefore, by using the threaded connector in the embodiment of the present application, the root stress can be effectively reduced, stress concentration can be avoided, the load-bearing capacity and fatigue resistance are stronger, and the performance of the threaded connection is improved.
[0037] In the embodiment of the present application, the cross-sectional shape of the thread groove 300 includes the first arc segment 320. The first arc segment 320 is smoothly connected to the first transition connection segment 310, and the first arc segment 320 is also smoothly connected to the second transition connection segment 330, so that the corner positions at the connection of the thread groove 300 are smoothly connected. In this way, when the threaded connector is connected to other threaded structures, the thread groove 300 is not easily interfered with the corner positions of other threads, which is beneficial to making the threaded connection tighter and improving the strength of the threaded connection.
[0038] Moreover, the radius dimension of the first arc segment 320 is related to the pitch of the thread. The radius of the first arc segment 320 is not too large, effectively avoiding interference at the corner positions between the thread groove 300 and other threads. Also, the radius of the first arc segment 320 is not too small, preventing the strength of the threaded connector from being affected.
[0039] Existing thread specifications usually include three types. The first type has 4 thread protrusions 200 per inch in the axial direction of the thread, that is, the pitch P = 6.35 mm, and the radius R of the first arc segment 320 = 1.0 mm - 1.35 mm; the second type has 3 thread protrusions 200 per inch in the axial direction of the thread, that is, the pitch P = 8.467 mm, and the radius R of the first arc segment 320 = 1.3 mm - 1.85 mm; the third type has 3.5 thread protrusions 200 per inch in the axial direction of the thread, that is, the pitch P = 7.257 mm, and the radius R = 1.1 mm - 1.59 mm.
[0040] In an alternative embodiment, the radius R of the first arc segment 320 = 0.2P - 0.22P. In the range of radius R = 0.15P - 0.22P, the larger the radius R of the first arc segment 320, the better. Therefore, the radius R = 0.2P - 0.22P, indicating that within a suitable range, the radius of the first arc segment 320 is relatively large, which can not only avoid interference at the corner positions with other threads and prevent stress concentration, but also effectively improve the strength of the threaded connector.
[0041] Of course, in other embodiments, the radius R of the first arc segment 320 can be 0.15P - 0.2P.
[0042] In an alternative embodiment, the first end of the first arc segment 320 is smoothly and transitionally connected to the first transition connection segment 310, and the second end of the first arc segment 320 is smoothly and transitionally connected to the second transition connection segment 330. That is to say, the tangential direction of the first end of the first arc segment 320 is parallel to the extension direction of the first transition connection segment 310, and the tangential direction of the second end of the first arc segment 320 is parallel to the extension direction of the second transition connection segment 330.
[0043] Adopting this embodiment, the connection between the first arc segment 320 and the first transition connection segment 310 and the connection between the first arc segment 320 and the second transition connection segment 330 are more natural, and can more effectively avoid the problem of stress concentration.
[0044] Of course, in other embodiments, the first end of the first arc segment 320 and the first transition connection segment 310 may not be smoothly transition-connected. That is to say, the tangential direction of the first end of the first arc segment 320 is different from the extension direction of the first transition connection segment 310; the second end of the first arc segment 320 and the second transition connection segment 330 may not be smoothly transition-connected. That is to say, the tangential direction of the second end of the first arc segment 320 is different from the extension direction of the second transition connection segment 330.
[0045] In an alternative embodiment, in the axial direction of the thread, the cross-sectional shape of some of the thread grooves 300 includes a first transition connection segment 310, a first arc segment 320, and a second transition connection segment 330.
[0046] In another embodiment, in the axial direction of the thread, the cross-sectional shape of each of the thread grooves 300 includes a first transition connection segment 310, a first arc segment 320, and a second transition connection segment 330.
[0047] With this embodiment, each thread groove 300 of the threaded connector adopts the above structure, so that the corner positions at the joints of the respective thread grooves 300 are all smoothly connected, and the corner positions of each thread groove 300 are not likely to interfere with the corner positions of other threads, which is more conducive to making the threaded connection tighter and is conducive to further improving the strength of the threaded connection.
[0048] In an alternative embodiment, both the first transition connection segment 310 and the second transition connection segment 330 are linear structures. Optionally, the first transition connection segment 310 and the second transition connection segment 330 have the same length, and their inclination angles with respect to the first arc segment 320 are equal.
[0049] According to the foregoing, the thread structure in the related art is usually a trapezoidal structure. With this embodiment, the first transition connection segment 310 and the second transition connection segment 330 can respectively directly cooperate with the thread protrusions 200 of the thread in the prior art, which is conducive to making the threaded connection tighter and improving the strength of the threaded connection.
[0050] Of course, in other embodiments, the first transition connection segment 310 and the second transition connection segment 330 may also be other structures.
[0051] In an alternative embodiment, the cross-sectional shape has a symmetry plane. The first transition connection segment 310 and the second transition connection segment 330 are symmetric about the symmetry plane, and the first arc segment 320 is symmetric about the symmetry plane. That is to say, the cross-sectional shape of the thread groove 300 in the axial direction of the thread is a symmetric structure.
[0052] It should be noted that the symmetry plane is perpendicular to the axial direction of the thread, and the symmetry plane passes through the midpoint of the first arc segment 320.
[0053] According to this embodiment, in the axial direction of the thread, the cross-sectional shape of the thread groove 300 is a symmetrical structure. Therefore, not only can the threaded connector be matched with the thread structure in the related art, but also, with reference to Figure 6 As shown, the threaded connector with the internal thread 121 as the thread structure can be matched with the threaded connector with the external thread 111 as the thread structure, that is, the internal thread 121 and the external thread 111 with the same thread structure can be directly matched, so that the application range of the threaded connector is wider and the applicable types are increased.
[0054] Of course, in other embodiments, the cross-sectional shape of the thread groove 300 in the axial direction of the thread may adopt an asymmetric structure.
[0055] In an optional embodiment, reference Figure 2 As shown, in the axial direction of the thread, the cross-sectional shape of the thread protrusion 200 includes a third transition connecting section 210. In two adjacent thread grooves 300, the first transition connecting section 310 of one thread groove 300 is connected to the second transition connecting section 330 of the other thread groove 300 through the third transition connecting section 210, and the third transition connecting section 210 is a linear structure. Optionally, in the axial direction of the thread, the cross-sectional shape of the thread protrusion 200 is also a symmetrical structure.
[0056] refer to Figure 4 As shown, when the thread of the threaded connector is an external thread 111, it can cooperate with the thread structure with an internal thread 121 in the related art, and the third transition connection section 210 cooperates with the groove bottom of the thread structure in the related art; Figure 5 As shown, when the thread of the threaded connector is an internal thread 121, it can cooperate with the thread structure with an external thread 111 in the related art, and the third transition connection section 210 cooperates with the groove bottom of the thread structure in the related art; Figure 6 As shown, the threaded connector with the external thread 111 can be matched with the threaded connector with the internal thread 121, and there is a gap between the third transition connection section 210 and the first arc section 320 of the threaded structure, and the third transition connection section 210 avoids the first arc section 320 to avoid mutual influence. In other words, whether the threaded structure is the external thread 111 or the internal thread 121, the threaded connector can be matched with at least two types of threaded structures, that is, the threaded connector can be matched with the threaded structure in the related art and the threaded structure in the embodiment of the present application.
[0057] With this embodiment, since the third transition connection section 210 is a linear structure, the third transition connection section 210 can not only cooperate with the bottom of the groove of the existing thread structure, but also avoid the first arc section 320 of the thread structure in the embodiment of the present application, increasing the matching types of the threaded connector and making the application range of the threaded connector wider.
[0058] In another embodiment, as shown in Figure 3 In the axial direction of the thread, the cross-sectional shape of the thread protrusion 200 includes a second arc section 220. Among two adjacent thread grooves 300, the first transition connection section 310 of one thread groove 300 is connected to the second transition connection section 330 of the other thread groove 300 through the second arc section 220. The second arc section 220 has the same structure as the first arc section 320. Optionally, the cross-sectional shape of the thread protrusion 200 is the same as the cross-sectional shape of the thread groove 300. Optionally, in the axial direction of the thread, the cross-sectional shape of the thread protrusion 200 is also a symmetric structure.
[0059] As shown in Figure 7 The threaded connector with the above thread structure as the external thread 111 can cooperate with the threaded connector with the above thread structure as the internal thread 121. In this way, there is no gap between the external thread 111 and the internal thread 121, which is beneficial to the closer cooperation between the external thread 111 and the internal thread 121 and improves the strength of the thread connection.
[0060] Based on the threaded connector disclosed in the present application, an embodiment of the present application also discloses a thread connection assembly. The thread connection assembly includes a first threaded connector 110 and a second threaded connector 120. The first threaded connector 110 and the second threaded connector 120 are connected. At least one of the first threaded connector 110 and the second threaded connector 120 is the threaded connector in the above embodiment. The first threaded connector 110 and the second threaded connector 120 are connected through the external thread 111 and the internal thread 121. It can be that only the first threaded connector 110 or only the second threaded connector 120 is the threaded connector in the above embodiment, or both the first threaded connector 110 and the second threaded connector 120 are the threaded connectors in the above embodiment.
[0061] With this embodiment, the threaded connector of the thread connection assembly can not interfere with other thread structures, which is beneficial to closer thread connection and improves the strength of the thread connection.
[0062] In an alternative embodiment, the connecting body 100 of the first threaded connector 110 is provided with an external thread 111, and the connecting body 100 of the second threaded connector 120 is provided with an internal thread 121. The external thread 111 cooperates with the internal thread 121, and the external thread 111 or the internal thread 121 is the thread of the threaded connector in the above embodiment. That is to say, only the first threaded connector 110 or only the second threaded connector 120 adopts the threaded connector in the above embodiment.
[0063] In another embodiment, referring to Figure 6 and Figure 7 the structure shown, both the external thread 111 and the internal thread 121 are the threads of the threaded connector in the above embodiment. That is to say, both the first threaded connector 110 and the second threaded connector 120 are the threaded connectors in the above embodiment.
[0064] By adopting this embodiment, the thread structures of the two components connected by the threaded connection assembly both adopt structures that are not prone to interference, which is more conducive to making the threaded connection tighter and is beneficial to further improving the strength of the threaded connection.
[0065] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose of the present application and the scope protected by the claims, and all of them fall within the protection scope of the present application.
Claims
1. A threaded connector, characterized in that, It includes a connecting body (100). The connecting body (100) is provided with threads. The threads include multiple turns of thread protrusions (200). A thread groove (300) is formed between two adjacent turns of the thread protrusions (200). In the axial direction of the threads, the cross-sectional shape of the thread groove (300) includes a first transition connection section (310), a first arc section (320), and a second transition connection section (330). The two ends of the first arc section (320) are respectively connected to the first transition connection section (310) and the second transition connection section (330). The radius R of the first arc section (320) is related to the pitch P of the threads, and the radius R of the first arc section (320) = 0.15P - 0.22P.
2. The threaded connector according to claim 1, wherein, The first end of the first arc section (320) is smoothly and transitionally connected to the first transition connection section (310), and the second end of the first arc section (320) is smoothly and transitionally connected to the second transition connection section (330).
3. The threaded connector according to claim 1, characterized in that, In the axial direction of the threads, the cross-sectional shape of each thread groove (300) includes the first transition connection section (310), the first arc section (320), and the second transition connection section (330).
4. The threaded connector according to claim 1, wherein, Both the first transition connection section (310) and the second transition connection section (330) are linear structures.
5. The threaded connector according to claim 1, characterized in that, The cross-sectional shape has a symmetry plane. The first transition connection section (310) and the second transition connection section (330) are symmetric about the symmetry plane, and the first arc section (320) is symmetric about the symmetry plane.
6. The threaded connector according to claim 1, characterized in that, In the axial direction of the threads, the cross-sectional shape of the thread protrusion (200) includes a second arc section (220). Among two adjacent thread grooves (300), the first transition connection section (310) of one thread groove (300) is connected to the second transition connection section (330) of the other thread groove (300) through the second arc section (220). The second arc section (220) has the same structure as the first arc section (320).
7. The threaded connector according to claim 1, characterized in that, In the axial direction of the threads, the cross-sectional shape of the thread protrusion (200) includes a third transition connection section (210). Among two adjacent thread grooves (300), the first transition connection section (310) of one thread groove (300) is connected to the second transition connection section (330) of the other thread groove (300) through the third transition connection section (210). The third transition connection section (210) is a linear structure.
8. The threaded connector according to claim 1, characterized in that, The radius R of the first arc section (320) = 0.2P - 0.22P.
9. A threaded connection assembly, characterized in that, It includes a first threaded connector (110) and a second threaded connector (120). At least one of the first threaded connector (110) and the second threaded connector (120) is the threaded connector according to any one of claims 1 - 8.
10. The threaded connection assembly according to claim 9, characterized in that, The connecting body (100) of the first threaded connector (110) is provided with an external thread (111), the connecting body (100) of the second threaded connector (120) is provided with an internal thread (121), the external thread (111) is matched with the internal thread (121), and both the external thread (111) and the internal thread (121) are the threads of the threaded connector according to any one of claims 1-8.