Single-head locking bolt

Abstract

A single head anti-loose locking bolt is used for locking a locking member on a base member at a locking hole of the base member, and is composed of a single head bolt, a nut, a ratchet washer, and a knurled layer of the locking member in sequence. The ratchet washer is provided with a knurled layer close to the end face of the nut. The ratchet washer is matched with the knurled layers on both sides, the ratchet washer is provided with ratchets protruding on both sides in the axial direction, the ratchets are respectively embedded in the knurled grooves of the knurled layers, and the interference fit is formed under the tightening pressure, so that the nut and the adjacent locking member are integrated. Since the ratchets are embedded in the knurled grooves to connect the components on both sides and cannot rotate relative to each other, the locking member and the base member cannot be loosened, so that the anti-loose effect is achieved.

Description

Technical Field

[0001] This utility model relates to mechanical fasteners, specifically a single-headed anti-loosening locking bolt. Background Technology

[0002] The most convenient and quickest way to fasten fasteners is usually with screws or bolts. However, these fasteners are prone to loosening after a period of vibration, losing their tightening function, which can pose a safety hazard, especially in critical applications. Traditional methods for preventing bolt loosening include using reverse threads, Tang bolts with a pair of interlocking washers, eccentric nuts, spring washers, winged washers, double nuts, adhesive application, or nylon threaded pairs. These methods are not only complex to operate, but also fail to meet the residual torque requirements for high-specification applications after lateral vibration, such as the anti-loosening requirements for high-speed rail contact networks. The highest current standard is ISO 16130:2015, which requires the ratio of residual axial force to initial axial force after lateral vibration to be greater than 85%.

[0003] In its invention application "Locking Device for Railway Contact Network" (application number 2024115046919), the applicant disclosed a fastening device with high anti-loosening performance. A key technology disclosed in this application involves using a ratchet washer and the knurled end faces of the nuts on both sides of the ratchet washer to secure the device together. However, this requires a pair of nuts with opposite rotation directions. If space constraints prevent sufficient bolt length, the use of a pair of nuts is limited. Summary of the Invention

[0004] The technical problem to be solved by this utility model is to provide a single-headed anti-loosening locking bolt that further compresses the space requirements in the axial direction, simplifies the structure and operation, while maintaining the anti-loosening effect at a high level that meets ISO16130:2015.

[0005] The single-headed anti-loosening locking bolt is characterized in that it is used to lock the locking device onto the base component at the locking hole of the base component, and is characterized in that it is composed of a single-headed bolt, a nut, a ratchet washer, and a knurled layer of the locking device in sequence, wherein the end face of the nut adjacent to the ratchet washer is provided with a knurled layer.

[0006] Furthermore, the single-ended bolt is threaded to the locking fastener, and the threads at the mating nut and the locking fastener have opposite directions of rotation. This significantly enhances the anti-loosening effect.

[0007] The ratchet washer has ratchet teeth on its radial inner or outer ring. The ratchet teeth are twisted, and the two sides of the ratchet teeth protrude from the two end surfaces of the washer.

[0008] As an example, the knurled layer is provided with a spiral knurled groove, and the width of the knurled groove is interference-fitted with the protruding ratchet teeth of the ratchet washer.

[0009] Alternatively, the knurled layer may have bidirectional spiral knurled grooves, the width of which smoothly narrows from the outer ring to the inner ring.

[0010] This invention achieves high fastening and anti-loosening effects with a minimalist structure, fewer parts, and smaller axial space requirements. Sample testing showed that when the tightening torque is 44 Newtons, the loosening torque is no less than 60 Newtons, far exceeding the industry standard requirement that the loosening torque should not be less than the tightening torque. After lateral vibration testing, the residual axial force exceeded the international standard ISO16130:2015 requirement that the ratio of residual axial force to initial axial force after lateral vibration be greater than 85%, with actual measurements exceeding 90%. This surpasses current anti-loosening bolt technology.

[0011] This utility model features a ratchet washer that fits into the knurled layers on both sides. The ratchet washer has ratchet teeth protruding from both sides axially, with each side of the ratchet teeth embedded in the knurled grooves of the knurled layers. Under tightening pressure, an interference fit is formed, securing the nut and the adjacent locking component together. Because the ratchet teeth embedded in the knurled grooves connect the components on both sides and prevent relative rotation, the locking component and the base component cannot be loosened, thus providing an anti-loosening function.

[0012] When the bolt and locking fastener are threadedly connected and the threads at the locking fastener and nut rotate in opposite directions, the nut, unable to move forward due to its clamping force, will rotate in the same direction as the locking fastener, causing it to move backward. However, this rotation only propels the locking fastener forward, clamping the nut even tighter and preventing it from loosening. In contrast, if the locking fastener is a large structural component that cannot rotate on its own, the ratchet knurled structure directly secures the fastener and nut together, preventing loosening even with a single-ended bolt. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view of the utility model in use.

[0014] Figure 2 This is a view of the knurled end face of the lock nut.

[0015] Figure 3 This is a planar structural diagram of a ratchet washer.

[0016] Figure 4 yes Figure 3 Side view.

[0017] Figure 5 This is a planar structural diagram of another type of ratchet washer.

[0018] Figure 6 yes Figure 5 AA section view.

[0019] In the diagram: 1-Nut, 2-Ratchet washer, 3-Knurled layer, 4-Locking component, 5-Base component, 6-Single-ended bolt, 7-Bolt head, 8-Locking hole, 9-Knurled groove, 10-Ratchet. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments: One end of the single-headed bolt of the present invention is integrally provided with a radially expanded bolt head 7. The bolt head is usually hexagonal columnar, and the part outside the bolt head is a stud.

[0021] The single-headed anti-loosening locking bolt is used to lock the locking member 4 onto the base member 5 at the locking hole 8, such as... Figure 1 The bolt fastening system shown consists of a single-ended bolt 6, a base component 5, a locking component 4, a knurled layer 3 on the locking component 4, a ratchet washer 2, and a nut 1. The end face of the nut 1 adjacent to the ratchet washer 2 is provided with the knurled layer 3, and the base component 5 is adjacent to the bolt head 7.

[0022] The ratchet washer 2 has ratchet teeth 10 on its radial inner or outer ring, such as... Figure 3-6 The figures shown are examples of two types of ratchet washers. Figure 3 , 4 For ratchet 10 on the outer ring of the washer, Figure 5 , 6 The ratchet 10 is an inner ring structure of the washer, with the ratchet distributed around the circumference. Each piece of the ratchet 10 is twisted relative to the plane of the washer, so that the two sides of the ratchet 10 protrude from the two end surfaces of the washer.

[0023] The knurled layer 3 is provided with spiral knurled grooves 9, such as... Figure 2As shown, in the installed state, the width of the knurled groove 9 is in an interference fit with the protruding ratchet teeth 10 of the ratchet washer 2. Preferably, the knurled layer 3 has a bidirectional spiral knurled groove 9, and in the part state, the width of the knurled groove 9 smoothly narrows from the outer circle to the inner circle. The width of the knurled groove 9 is wider on the outer circle of the spiral and narrower on the inner circle, with a smooth change in width, and the narrower part is in an interference fit with the protruding ratchet teeth 10 of the ratchet washer. The bidirectional spiral knurled groove 9 has two advantages: when tightening, some of the ratchet teeth 10 are embedded in the knurled groove 9 and then pressed into the narrower knurled groove 9, forming an interference fit, and fixing the nut 1 and the locking fastener 4 together. During vibration, the reverse spiral knurled groove 9 makes the fit between the ratchet teeth 10 and the knurled groove 9 even tighter. Although some of the ratchet teeth 10 are located in the knurled grooves 9, there is a tendency for them to loosen during reverse movement. However, some ratchet teeth 10 remain within the narrower knurled grooves 9 during reverse movement, thus restraining the tendency to loosen and preventing the fastener 1 and the locking fastener 4 from shaking. Therefore, the fastener can still be prevented from loosening during vibration. As an example, the ratchet washer is made of Q235A steel, and the nut and bolt that mate with the ratchet washer are made of 45# steel. The ratchet washer is less hard than the nut, and under the pressure of the nut, the ratchet washer deforms and partially embeds itself into the knurled grooves, significantly increasing the friction.

[0024] In a preferred embodiment, the inner wall of the locking hole 8 of the base component 5 is a smooth, unthreaded hole. The single-headed bolt 6 is threadedly connected to the locking fastener 4, and the threads at the mating nut 1 and locking fastener 4 have opposite directions of rotation. When the threads of the nut 1 and locking fastener 4 are opposite and tightened, for example, the locking fastener 4 is tightened to the right, pressing against the base component 5, and the nut 1 is tightened to the left, securing the nut 1 and locking fastener 4 together via the ratchet 10. During lateral vibration, if the nut 1 exhibits a left-hand rotation tendency, it will press the locking fastener 4 forward. If it exhibits a right-hand rotation tendency, since the nut 1 and locking fastener 4 are secured together, it will cause the locking fastener 4 to rotate to the right. The right-hand rotation of the locking fastener 4 will only cause it to press against the base component 5, resulting in a further tightening tendency. Therefore, the entire system cannot be loosened. To loosen it manually, a torque exceeding the initial axial force must be used to forcibly unlock the ratchet connection. When using a bolt with bidirectional threads, it is necessary to select a bolt whose length from the bidirectional thread dividing line to the screw head 7 matches the thickness of the locking fastener 4 plus the base component 5.

[0025] The above embodiments can be used in combination as needed.

[0026] For tightening, a knurled layer 3 needs to be pre-made on one end face of the opening of the fastener by extrusion or turning. During operation, the base component 5, the fastener 4, the knurled layer 3 of the fastener 4, the ratchet washer 2, and the nut 1 are sequentially placed on the outside of the stud of the single-ended bolt 6. Tighten the nut 1 with a torque wrench to the initial torque to achieve sufficient loosening effect. The operation is simple and effective. To disassemble, loosen the nut 1 with a force exceeding the initial torque.

Claims

1. A single-headed anti-loosening locking bolt, characterized in that: Used to lock the fastener (4) onto the base (5) at the locking hole (8), characterized in that: it is composed of a single-headed bolt (6), a nut (1), a ratchet washer (2), and a knurled layer (3) of the fastener (4) in sequence, wherein the end face of the nut (1) adjacent to the ratchet washer (2) is provided with a knurled layer (3).

2. The single-headed anti-loosening locking bolt according to claim 1, characterized in that: The single-headed bolt (6) is threaded to the locking fastener (4), and the threads at the mating nut (1) and the locking fastener (4) are opposite in direction.

3. The single-headed anti-loosening locking bolt according to claim 1, characterized in that: The ratchet washer (2) has ratchet teeth (10) on the radial inner or outer ring of the washer. The ratchet teeth (10) are twisted and the two sides of the ratchet teeth (10) protrude from the two end surfaces of the washer.

4. The single-headed anti-loosening locking bolt according to claim 3, characterized in that: The knurled layer (3) is provided with a spiral knurled groove (9), and the width of the knurled groove (9) is interference-fitted with the protruding ratchet (10) of the ratchet washer (2).

5. The single-headed anti-loosening locking bolt according to claim 3, characterized in that: The knurled layer (3) is provided with bidirectional spiral knurled grooves (9), the width of which smoothly narrows from the outer ring to the inner ring.

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