Low cost self locking lock nut

Abstract

This utility model discloses a low-cost self-locking anti-loosening nut, comprising a nut component and a locking component. The nut component is located within the locking component and is closed by a protruding buckle on a non-contact surface. The nut component includes a concentric outer cone and an outer hexagonal body, with the outer cone at the bottom and its outer circumferential surface being conical, and the outer hexagonal body at the top and its outer circumferential surface being regular hexagonal. The nut component has a notch that runs from top to bottom through the outer hexagonal body and the outer cone; there can be one or two notches, or three or more symmetrical notches. The locking component is hexagonal in shape and includes a concentric inner hexagonal body and an inner cone, with a stepped hole machined in its center. The central hole of the inner hexagonal body is a regular hexagonal hole, and the central hole of the inner cone is a conical hole. A reinforcing ring is provided at the bottom of the locking component to increase strength. This utility model has a simple structure, short production process, low manufacturing cost, full contact between the inner and outer nuts, and good anti-loosening effect.

Description

Technical Field

[0001] This utility model applies to the field of fasteners, specifically to fastening nuts, and more specifically to a nut with anti-loosening function. Background Technology

[0002] Nuts and bolts are widely used fasteners. The thread allows the rotational movement of the nut to be converted into linear movement along the bolt, thus securing the object. However, under vibration or when the elastic preload gradually disappears, the nut can loosen. To prevent loosening, many patent applications for anti-loosening nuts exist. CN2692401Y discloses a spring-loaded anti-loosening nut, which has a crescent-shaped groove machined on the internal thread of the nut, and a spring and ball bearings placed in the groove, using the ball bearings to prevent loosening. CN2851697Y discloses an anti-loosening and anti-dislodging nut, whose principle is the same as the above patents, consisting of a nut body and an outer sleeve, except that the blind hole for placing the spring and ball bearings is machined on the outer cylindrical surface of the nut body. CN2918843Y discloses an anti-loosening and anti-theft one-way bolt nut, which uses the fact that the bolt and nut can only rotate in one direction to achieve anti-loosening and anti-theft. CN211474633U A nut with a self-locking function includes a nut body and a locking component. The locking component is located in the middle of the nut body, and a clamping component is sleeved around the locking component. The locking component includes an outer hexagonal pyramidal edge and a limiting block. A pressure-reducing groove is formed between the upper end face of the outer hexagonal pyramidal edge and the bottom end face of the limiting block. A contraction groove is formed between the two sets of outer hexagonal pyramidal edges. Threaded strips are evenly distributed on the inner wall of the outer hexagonal pyramidal edge, and a threaded groove is formed between the two sets of threaded strips. When the nut is loosened, the inner hexagonal pyramidal edge of the clamping component can abut against the outer hexagonal pyramidal edge of the locking component. Under the compression of the reaction force, the outer hexagonal pyramidal edge of the locking component moves towards the center, completing the automatic locking of the locking component. When the locking component is locked by the pressure of the clamping component, the contraction groove plays a contraction role. At the same time, it can effectively reduce resistance when the clamping component touches the locking component, realizing the fixed positioning of the clamping component and the locking component. The applicant's application CN116428261A describes an anti-loosening nut that utilizes the elasticity of a spring to engage with the external thread of a bolt to prevent loosening. This nut has the advantages of good anti-loosening effect and low production cost.

[0003] The applicant previously applied for a self-locking anti-loosening nut (application number 2025221984004). During the test, it was found that the outer cone of a small number of nuts would undergo plastic deformation, which would make it difficult to reuse. Therefore, some structures were modified and manufacturing processes were reduced to lower production costs and enhance market competitiveness. Utility Model Content

[0004] The technical problem solved by this utility model is to provide a low-cost self-locking anti-loosening nut, which utilizes the contraction of the nut under external force to make the nut and bolt fully threaded into contact, thereby increasing friction and achieving anti-loosening.

[0005] The technical solution adopted in this utility model is as follows: This low-cost self-locking anti-loosening nut includes a nut component and a locking component. The nut component is placed inside the locking component and is closed by a protrusion on the non-contact surface of the locking component. The nut component includes a concentric outer cone and an outer hexagonal body. The outer cone is at the bottom, and its outer circumferential surface is conical. The outer hexagonal body is at the top, and its outer circumferential surface is regular hexagonal. The nut component has a notch that penetrates from top to bottom through the outer hexagonal body and the outer cone. The locking component is regular hexagonal in shape and includes a concentric inner hexagonal body and an inner cone with a stepped hole machined in the center. The inner hexagonal body is at the top, and its central hole is a regular hexagonal hole corresponding to its shape. The inner cone is at the bottom, and its central hole is a conical hole. A side ring is provided on the non-contact surface, and the side ring is pressure-machined into a protrusion.

[0006] Furthermore, the notch can be one or two. It can also be three or more symmetrically arranged. In this case, a flat washer should be provided between the nut and the protrusion to prevent the nut from detaching and to facilitate threaded connection.

[0007] Furthermore, the lower part of the locking member is provided with a reinforcing ring integrally formed with the locking member. The diameter of the reinforcing ring is not less than the circumcircle diameter of the regular hexagonal shape of the locking member. The reinforcing ring increases the strength of the locking member and prevents deformation. The lower end face of the reinforcing ring is flush with the contact surface of the locking member and can also serve as a flat washer.

[0008] Furthermore, the edge ring consists of multiple arc edges located at the corners of the inner hexagon, with the number of arc edges ranging from 2 to 6.

[0009] Furthermore, the vertical distance H between the lower end face of the nut and the contact surface of the locking component is not less than the vertical distance L between the lower end face of the outer hexagon and the lower end face of the inner hexagon. This is to prevent damage to the bolt threads caused by continuing to tighten the locking component after the lower end face of the nut contacts the surface of the object.

[0010] The beneficial effects of this utility model are: it has a simple structure, short production process, does not require special equipment, and has low manufacturing cost. After being tightened with the bolt thread, the inner and outer nuts are in full contact, increasing the thread friction and achieving an anti-loosening effect. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of Embodiment 1, and also... Figure 2 AA sectional view; Figure 2 yes Figure 1 A top-down view; Figure 3 This is a front view schematic diagram of the nut component in Example 1; Figure 4 yesFigure 3 A top-down view; Figure 5 This is a front view schematic diagram of the locking component in Embodiment 1, and also... Figure 6 BB cross-sectional diagram; Figure 6 yes Figure 5 A top-down view; Figure 7 This is a schematic diagram of the structure of Embodiment 2, and also... Figure 8 CC cross-sectional view; Figure 8 yes Figure 7 A top-down view; Figure 9 This is a schematic diagram of the structure of Embodiment 3; Figure 10 yes Figure 9 A top-down view; In the diagram: 1-nut, 2-locking component, 3-flat washer; 11-External cone, 12-External hexagon, 13-Notch, 14-Cone angle; 21-Inner cone, 22-Inner hexagon, 23-Side ring, 24-Convex buckle, 25-Reinforcing ring. Detailed Implementation

[0012] The following "above and below" are attached. Figure 1 and attached Figure 7 In terms of their relative positions, attached Figure 1 The object below needs to be tightened. The anti-loosening nut of this utility model is installed by screwing from top to bottom. Example

[0013] The structure of the anti-loosening nut in this embodiment is shown in the attached figure. Figure 1 and attached Figure 2 As shown, it includes a nut 1 and a locking member 2. The nut 1 is placed inside the locking member 2 and is closed by a protrusion 24 to prevent the nut 1 from detaching from the locking member 2. The lower end face of the locking member 2 is the contact surface with the object to be fastened, and the protrusion 24 is located on the upper end face (non-contact surface) of the locking member 2.

[0014] The structure of nut 1 is shown in the attached figure. Figure 3 and attached Figure 4 The nut component has an internal thread machined into its center hole to mate with the bolt. The nut component comprises an integrally formed outer cone 11 and an outer hexagon 12. The outer circumferential surface of the outer cone 11 is conical, and the outer circumferential surface of the outer hexagon 12 is a regular hexagon. The outer cone 11 is located below the outer hexagon 12 (see attached diagram). Figure 3 It is attached Figure 1 The purpose of turning the nut is to display the attached... Figure 4The two are concentric. A notch 13 is provided on the nut part 1, which penetrates from top to bottom through the outer hexagon 12 and the outer cone 11.

[0015] The structure of locking component 2 is shown in the appendix. Figure 5 and attached Figure 6 The locking component is hexagonal in shape, with its bottom surface serving as the contact surface for fastening the object. A side ring 23 is provided on the top non-contact surface, which can be pressure-processed into a protruding buckle 24. The inner cavity of the locking component 2 includes an integrally structured internal hexagonal body 22 and an internal cone 21. The inner cavity is a stepped hole, with the internal hexagonal body 22 located above the internal cone 21, and both concentric. The central hole of the upper internal hexagonal body 22 is a regular hexagonal hole corresponding to its shape, while the central hole of the lower internal cone 21 is a circular conical hole.

[0016] During assembly in this embodiment, as shown in the attached... Figure 1 As shown, the nut 1 is inserted into the center hole of the locking member 2. The outer conical surface of the outer cone 11 of the nut contacts the conical hole of the inner cone 21 of the locking member. The outer hexagon 12 of the nut fits into the inner hexagon 22 of the locking member, and the two are properly matched. Finally, the edge ring 23 is compressed and deformed into a protruding buckle 24 on a press.

[0017] When using this embodiment, the attached document will be... Figure 1 The anti-loosening nut engages with the bolt thread. Rotating the outer hexagonal locking element causes the inner hexagonal body 22 to rotate, which in turn drives the outer hexagonal body 12 of the nut to rotate, causing the nut and locking element 2 to move downwards simultaneously. When the lower end face (contact surface) of the locking element 2 contacts the object, the locking element continues to rotate. At this point, the locking element is blocked by the object and cannot move downwards, so it can only rotate on the surface of the object. Meanwhile, the nut continues to move downwards under the action of the thread as it rotates. At this time, the inner conical surface of the inner cone 21 presses against the outer conical surface of the outer cone 11, causing the nut to be squeezed by the locking element 2 and move horizontally in the radial direction, producing elastic deformation. The notch size decreases, increasing the contact area of ​​the inner and outer threads, thereby eliminating the fit clearance between the inner and outer threads. When the inner and outer threads are fully in contact, they cannot be tightened. At this point, the friction of the threaded fit is at its maximum, achieving the anti-loosening effect.

[0018] The structural description and dimensional relationship of the nut and locking parts are as follows: 1) Before using the self-locking anti-loosening nut, the vertical distance H between the lower end face of the nut and the contact surface of the locking part is not less than the vertical distance L between the lower end face of the outer hexagon of the nut and the lower end face of the inner hexagon of the locking part. That is, when the lower end face of the hexagon prevents the nut from moving down, the lower end face of the nut does not contact or just contacts the surface of the object, to prevent the lower end face of the nut from contacting the surface of the object and continuing to tighten the locking part, which would damage the bolt threads. 2) The notch 13 on the nut is a clearance space provided to ensure that the internal thread fully contacts the external thread. Usually, the size of the notch 13 is within the range of 0.3-1.5mm to meet the requirements. 3) The angle of the cone angle of the outer cone 11 and the inner cone 21 is related to the thread specification. It is advisable that the locking part can achieve full contact between the internal and external threads in less than one rotation. In other words, when the inner cone of the locking component presses against the outer cone of the nut component, the nut component should move downwards by no more than one thread pitch to eliminate the clearance between the internal and external threads and achieve full contact between them. From a dimensional design perspective, H should preferably be no less than one thread pitch, and L should preferably be no more than one thread pitch, consistent with the downward movement dimension of the nut component to achieve anti-loosening.

[0019] The preparation process of the anti-loosening nut in this embodiment is as follows: 1) Using different molds on a cold or hot heading machine, the locking part and nut blank are upset; 2) The nut blank is tapped to produce internal threads, becoming a semi-finished nut part; 3) The semi-finished nut part is sawn with notches to become a nut part; 4) On an assembly static press, the nut part is placed in the locking part, and the edge ring is cold-pressed into a protruding buckle, becoming the finished product. The assembly static press is the production equipment for producing anti-loosening nuts with plastic rings. It can be seen that the production of the anti-loosening nut does not use specialized equipment; only the mold needs to be modified. Although the notch processing step is added compared to anti-loosening nuts with plastic rings, this anti-loosening nut can be reused, while anti-loosening nuts with plastic rings can only be used once, and the plastic ring needs to be replaced the second time. Compared with a previously applied self-locking anti-loosening nut (application number 2025221984004), the machining process of the reducing groove is eliminated. For anti-loosening nuts produced in large quantities, this not only reduces the production cost of one process, but also reduces transportation and labor costs, thus lowering the overall production cost.

[0020] In this embodiment, the notch size is small, and the nut part can elastically deform within the assembly tolerance range of the internal and external threads, avoiding the plastic deformation of the outer cone and enabling the reuse of the anti-loosening nut. Example

[0021] The structure of the anti-loosening nut in this embodiment is shown in the attached figure. Figure 7 and attached Figure 8 As shown, it differs from Example 1 in the following ways: 1) An integral reinforcing ring 25 is added to the lower part of the locking component. The function of this reinforcing ring is to increase the strength of the inner cone 21 and prevent local deformation of the inner cone due to the reaction force of the outer cone, especially in areas where the outer straight edge of the inner cone is thinner. To enhance the reinforcing effect, the diameter of the reinforcing ring 25 is not less than the circumscribed circle diameter of the regular hexagonal shape of the locking component. Furthermore, the lower end face of the reinforcing ring 25 should preferably be flush with the lower end face (contact surface) of the locking component, also functioning as a washer.

[0022] 2) The edge ring 23 is not a complete circle, but rather 2-6 rounded edges located at the corners of the internal hexagon. The multiple protrusions 24 after the rounded edges are upset also serve the function of preventing the nut from coming off. Compared with embodiment 1, the protrusion material at the straight edge of the internal hexagon that does not contact the nut is eliminated, resulting in less material usage and reduced cost.

[0023] 3) In this embodiment, the nut is divided into two symmetrical parts. When the nut is placed in the locking mechanism, the fit between the inner and outer cones ensures that the nut has no gaps. Therefore, to facilitate connection with the bolt, a cone angle 14 is machined at the lower end of the internal thread of the nut. The contact between the cone angle 14 and the bolt shank causes the nut to rise while its sides expand. Under the positioning action of the snap 24, tightening connects the nut to the bolt thread. The fit clearance between the outer cone 11 and the inner cone 21 meets the requirements for internal and external thread connection.

[0024] Example 1 is applicable to small nuts, while this example is applicable to large nuts. During installation, the two half-nut pieces are respectively connected to the external threads of the bolt, and the two half-nut pieces are interchangeable. The production process of this example is the same as that of Example 1, and no special equipment is used. The process flow is consistent, except that the notch processing is changed from processing one notch to processing two symmetrical notches, both of which are done in one cut, without increasing costs.

[0025] In this embodiment, there are two notches and two half-nut parts. In the later stage of tightening, the inner cone of the locking part presses against the outer cone of the two half-nut parts, eliminating the fit gap between the inner and outer threads, realizing full contact between the inner and outer threads, and achieving the purpose of preventing loosening. Example

[0026] The structure of the anti-loosening nut in this embodiment is shown in the attached figure. Figure 9 and attached Figure 10As shown, the difference from Embodiment 2 is that the nut component is divided into three or more symmetrical pieces. To facilitate the threaded connection between the divided nut components and the bolt, and to prevent them from detaching within the locking component, a flat washer 3 is placed above the nut component. This flat washer 3 is located below the protrusion 24 and is installed within the locking component together with the nut component. The function of the flat washer 3 is to: 1) reduce the size of the upper opening of the locking component, preventing the nut component from detaching from the locking component; 2) ensure that the lifting and expansion actions of the nut component are consistent when the bolt shank lifts and expands the divided nut component, avoiding uneven force on the nut component caused by the protrusion and ensuring smooth threaded connection. Even if the protrusion 24 is a complete circle, it is advisable to install and use a flat washer to facilitate threaded connection. The shape of the flat washer 3 is not limited; it can be circular or hexagonal.

[0027] The production and installation of this embodiment are the same as in embodiment 2. After the anti-loosening nut and bolt are tightened, the inner and outer nuts are in full contact, and the nut does not undergo elastic deformation or plastic deformation, which facilitates the repeated use of the anti-loosening nut.

[0028] This invention features a simple structure. The locking component is formed by one-time upsetting, and the nut component, after being upsetting, has internal threads and notches machined. Then, the nut component is fitted into the locking component, and the upsetting protrusion is formed into the finished product. The production process is short, no special equipment is used, and the manufacturing cost is low.

Claims

1. A low-cost self-locking anti-loosening nut, comprising a nut component and a locking component, characterized in that: The nut is placed inside the locking member and is closed by the buckle (24) of the locking member; the buckle (24) is located on the non-contact surface of the locking member; The nut component includes a concentric outer cone (11) and an outer hexagon (12), with the outer cone (11) at the bottom and its outer circumferential surface being a cone, and the outer hexagon (12) at the top and its outer circumferential surface being a regular hexagon; the nut component is provided with a notch (13), which penetrates from top to bottom through the outer hexagon (12) and the outer cone (11). The locking component is hexagonal in shape, with a side ring (23) on its non-contact surface. The side ring (23) is pressure-processed into the buckle (24). The locking component includes an inner hexagon (22) and an inner cone (21) with a concentric integrated structure, and a stepped hole is machined in the center. The inner hexagon (22) is on top, and its central hole is a regular hexagonal hole corresponding to its shape. The inner cone (21) is on the bottom, and its central hole is a conical hole.

2. The low-cost self-locking anti-loosening nut according to claim 1, characterized in that: The gap (13) is one or two.

3. The low-cost self-locking anti-loosening nut according to claim 1, characterized in that: The notch (13) is three or more symmetrical; a flat washer (3) is provided between the nut and the buckle (24).

4. A low-cost self-locking anti-loosening nut according to claim 1, characterized in that: The lower part of the locking member is provided with a reinforcing ring (25) that is integral with the locking member.

5. A low-cost self-locking anti-loosening nut according to claim 4, characterized in that: The lower end face of the reinforcing ring (25) is flush with the contact surface of the locking member; the diameter of the reinforcing ring (25) is not less than the circumscribed circle diameter of the regular hexagonal shape of the locking member.

6. A low-cost self-locking anti-loosening nut according to claim 1, characterized in that: The edge ring (23) is a rounded edge located at the corner of the inner hexagon (22), and the number of the rounded edges is 2 to 6.

7. A low-cost self-locking anti-loosening nut according to claim 1, characterized in that: The vertical distance H between the lower end face of the nut and the contact surface of the locking member is not less than the vertical distance L between the lower end face of the outer hexagon (12) and the lower end face of the inner hexagon (22).

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