Single-head anti-loosening fastening device

Abstract

A single-head anti-loosening fastening device comprises a bolt and a bolt clamping screw. The non-overlapping part of the bolt head and the bolt body in the axial direction is provided with two or more through bolt clamping screw holes parallel to the axial direction, and the bolt clamping screw holes are used for being connected with bolt clamping screws in a threaded fit mode; the diameter of the bolt clamping tail of the bolt clamping screw shrinks towards the tail end, and the bolt clamping screw is used for being embedded into a locking groove of a contacted fastening object. On the premise that the single-head fastening device is convenient and reliable to install, the requirements of railway industry standards are met and exceeded, the loosening torque is larger than the fastening torque, mucilage glue does not need to be smeared, use is convenient, the single-head fastening device can be put into use immediately after being fastened, and loosening and disassembling are easy, convenient and rapid compared with an existing fastening device.

Description

Technical Field

[0001] The utility model relates to a mechanical fastening device, in particular to a single-head anti-loosening fastening device. Background Art

[0002] According to industry technical standards, the anti-loosening fasteners of the bearing oil box of my country's railway locomotive motors require that the loosening torque be no less than the tightening torque. The current method is to apply a special glue to the threaded part before installation and tightening. This imported glue is very expensive and has a limited use and storage period. The key is that it is very troublesome to use. The workpiece must be thoroughly cleaned and dried before applying the glue. After construction, it cannot be put into use immediately. It must wait until the glue is thoroughly solidified before it can withstand the vibration force during operation. When the motor malfunctions and needs to be repaired, the fasteners must be loosened and retightened. Such screws coated with glue are difficult to loosen with a wrench, and the residual glue is extremely difficult to deal with. In other words, there is currently no fastening device that is easy to use, avoids the above-mentioned defects, and meets the technical standards of the railway industry. Summary of the Invention

[0003] The technical problem to be solved by the utility model is to provide a single-head anti-loosening fastening device, which can be used easily, can be put into use immediately after fastening, is reliable in use, and is relatively convenient to loosen and release.

[0004] A single-head anti-loosening fastening device, characterized in that: the fastening device includes a bolt and a locking screw;

[0005] The bolt comprises a cylindrical bolt body with threads and an integrally formed bolt head. The circumscribed diameter of the bolt head is 1.4 to 2.8 times the outer diameter of the bolt body. The bolt head is provided with two or more through and parallel bolt-clamping screw holes in the axial direction in the non-overlapping portion with the bolt body for connection with the bolt-clamping screw thread.

[0006] The bolt clamping screw is coaxially and integrally provided with a bolt clamping head, a bolt clamping body and a bolt clamping tail in sequence in the axial direction. The bolt clamping body is provided with an external thread. The diameter of the bolt clamping tail shrinks towards the tail end and is used to be embedded in the locking groove of the fastener it contacts.

[0007] Furthermore, a binding wire is provided, and a binding hole is passed through the bolt clamp head perpendicular to the axial direction of the bolt clamp screw. The binding wire passes through the binding hole of each bolt clamp screw in turn and is fixed in a closed loop.

[0008] Furthermore, an independent annular sheet-shaped ratchet washer is provided, which is sleeved outside the bolt body and embedded between the bolt head and the fastener; the end faces of both sides of the ratchet washer are provided with annularly distributed ratchets, and the ratchet is formed by the intersection of the ratchet back side and the ratchet front side protruding from the surface of the washer body to form an acute angle.

[0009] Preferably, the cross section of the bolt clamp head of the bolt clamp screw is square, the maximum outline perpendicular to the axial direction does not exceed the bolt clamp body, and the binding hole opening is staggered with the square edge of the bolt clamp head.

[0010] Preferably, the tail end of the locking screw is contracted to a 90° top angle.

[0011] As an embodiment, the bolt screw is made of 35CrMoA quenched and tempered steel, and the quenched and tempered hardness of the tail end is HRc45-50.

[0012] Preferably, the angle between the back side of the ratchet and the tightening direction of the bolt is 20° to 30°, the angle between the front side of the ratchet and the tightening direction of the bolt is 80° to 95°, and the ratchet height is 2±0.5 mm.

[0013] The inner circle of the fitting surface between the ratchet washer and the bolt head is provided with a chamfer to improve the fitting degree between the ratchet washer and the bolt head.

[0014] As an embodiment, the ratchet washer is made of 65Mn with a quenching and tempering hardness of HRc40-52.

[0015] The ratchet washer is only one independent piece.

[0016] The utility model realizes for the first time that the fastening device is easy and reliable to install, meets and exceeds the requirements of railway industry standards, the loosening torque is greater than the tightening torque, no adhesive is required, it is easy to use, can be put into use immediately after tightening, and loosening and removing are simpler and faster than existing fastening devices.

[0017] The utility model inserts a locking screw through the bolt head, and the tip of the tail end of the locking screw is embedded in the locking groove of the fastener, which restricts the rotation and outward movement of the bolt. Since it is fastened to the machine body as a whole, it does not affect the strength of the fastener. Therefore, the locking is very stable and reliable.

[0018] Using binding wire to fix multiple bolt screws together limits the rotation of any bolt screw while increasing the friction between the bolt and the bolt, further limiting the rotation of the bolt screw, thereby also resisting the influence of vibration on the loosening of the bolt.

[0019] The use of ratchet washers allows the tips of the ratchet teeth to pass smoothly when tightening the bolts, while both sides provide resistance when loosening. The metal elasticity of the washers themselves also provides pre-tightening force, further enhancing the anti-loosening performance. Installation and removal are simple and quick.

[0020] Existing bolt locking systems often use a hole punched through the center of the bolt (e.g., self-retracting, expansion, tensioning, etc.), which significantly reduces the strength of the bolt itself. This new design maintains a solid bolt structure, preserving its strength. The locking screws mutually constrain each other, preventing them from rotating or coming out of the recess, ensuring the bolt's stability and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the utility model in use state.

[0022] Figure 2 yes Figure 1 Right view of .

[0023] Figure 3 It is the main view of the single-head bolt structure schematic diagram.

[0024] Figure 4 yes Figure 3 Right view of .

[0025] Figure 5 It is the main view of the structural diagram of the bolt screw.

[0026] Figure 6 yes Figure 5 Right view of .

[0027] Figure 7 It is the main view of the ratchet washer structure schematic diagram.

[0028] Figure 8 yes Figure 7 AA section view of the .

[0029] Figure 9 yes Figure 7 rear view.

[0030] Figure 10 yes Figure 7 Middle BB cross-section view.

[0031] In the figure: 1-machine body, 2-fastener, 3-locking slot, 4-bolt head, 5-bolt screw, 6-binding hole, 7-bolt screw hole, 8-ratchet washer, 9-bolt head, 10-binding wire, 11-bolt body, 12-bolt tail, 13-bolt body, 14-bolt, 15-transition arc, 16-ratchet, 17-back side of ratchet, 18-front side of ratchet, 19-chamfer. DETAILED DESCRIPTION

[0032] The present invention is further described below with reference to the accompanying drawings and embodiments: Figure 1 In the description of this manual, Figure 1 The right side of each component is described as the head of the corresponding component, and the direction toward the body 1 is the tail.

[0033] Attachment Figure 1 This is a schematic diagram of the overall use and installation status of the fastening device. Figure 1 It can be seen that the single-head anti-loosening fastening device fastens the fastener 2 and the body 1 into one through the preset threaded hole of the body 1. The single-head anti-loosening fastening device does not contain a nut, but only has a single-head bolt 4. The core components of the single-head anti-loosening fastening device are the bolt 14 and the clamping screw 5.

[0034] like Figure 3 、 4 As shown, the structure of the bolt 14 is a single component, the head is the bolt head 4, the head is an integrally formed cylindrical bolt body 13 with threads, the tail is threaded, and there may be a polished rod between the thread and the bolt head. The typical structure of the bolt head 4 is columnar, with Figure 3 、 4 The bolt head 4 is a common hexagonal head with a hexagonal cross-section. Other shapes are permitted, provided the thickness is not less than the nominal thickness of the bolt head. The bolt head 4 and the bolt body 13 are coaxial. The circumscribed circle diameter of the bolt head 4 is 1.4 to 2.8 times the outer diameter of the bolt body 13. The bolt head 4 axially overlaps with the projection of the bolt body on the shank. The non-overlapping portion of the circle is provided with two or more through-holes 7 extending parallel to the axial direction for threaded engagement with the bolt screw 5. In this embodiment, there are three equally spaced holes 7.

[0035] The connection between the bolt head 4 and the bolt body 13 has a transitional R arc, such as Figure 3 The transition arc 15 shown by the reference numeral 15 in the figure is beneficial to improving the torsional strength during twisting.

[0036] As an embodiment, the material of the bolt 14 is 35CrMoA, which has been quenched and tempered.

[0037] like Figure 5 、 6 As shown, the bolt screw 5 is threadedly connected to the bolt hole 7 and partially embedded in the fastener 2 under the guidance of the bolt hole 7. The bolt screw 5 is coaxially provided with a bolt head 9, a bolt body 11 and a bolt tail 12 in the axial direction from the head to the tail.

[0038] The bolt clamp head 9 is designed to be clamped and twisted, driving the bolt clamp body 11 to rotate and push the bolt clamp tail 12. In this embodiment, the bolt clamp head 9 of the bolt clamp screw 5 has a square cross-section to facilitate clamping and twisting. The maximum profile perpendicular to the axial direction does not exceed the bolt clamp body 11. The lashing hole 6 has a flat opening on the side, which is staggered with the square edge of the bolt clamp head 9.

[0039] The bolt body 11 is provided with an external thread from the head to the middle thereof, which matches the bolt screw hole 7. The diameter of the bolt tail 12 shrinks toward the tail end, so as to be embedded in the locking groove 3 of the fastener in contact. Figure 5 In the embodiment, the tail end of the locking screw 5 is contracted to a 90° top angle.

[0040] As an application example, the clamping screw 5 is made of 35CrMoA quenched and tempered steel, and the quenching and tempering hardness of the tail end is HRc45-50.

[0041] The tip of the tail end of the bolt is embedded in the locking groove 3 at the corresponding position of the fastener, which limits the rotation and outward movement of the bolt. Since it is fastened to the body 1 as a whole, it does not affect the strength of the fastener. Therefore, the locking is very stable and reliable.

[0042] As a further example, Figure 2 As shown, the bolt clamp 9 is provided with a binding hole 6 extending perpendicularly to the axis of the bolt screw, for passing a binding wire 10. The bolt clamp 9 has a square cross-section to facilitate clamping and twisting. The binding wire 10 passes through the binding hole 6 of each bolt screw 5 in sequence, securing the ends of the binding wires 10 in a closed loop. The binding wires secure the multiple bolt screws together, limiting the rotation of any individual bolt screw and increasing friction with the bolts, further limiting rotation and thus preventing vibration from loosening the bolts.

[0043] In a further embodiment, an independent annular ratchet washer 8 is provided, such as Figure 7-10 As shown, the ratchet washer 8 is sleeved outside the bolt body 13 and embedded between the bolt head 4 and the fastener 2. The end faces of the ratchet washer 8 are provided with annularly distributed ratchet teeth 16, and the ridges of the ratchet teeth 16 are radially distributed with the axis as the center, as shown in FIG. Figure 10The surface of each ratchet 16 is composed of a ratchet back side 17 and a ratchet front side 18 protruding from the surface of the washer body. The angle between the ratchet back side 17 and the tightening direction of the bolt 14 is 20° to 30°, and the angle between the ratchet front side 18 and the tightening direction of the bolt 14 is 80° to 95°. The ratchet height is 2±0.5mm. The ridges on the top of the ratchet are sharp, which is sufficient to block the rotation of the bolt head 4 in the loosening direction. In the tightening direction, the bolt head 4 can easily sweep over the ratchet back side 17. In the embodiment, the ratchet has 32 evenly distributed rings. In order to increase the one-way rotation effect, radial grooves or protrusions can also be provided on the inner end face of the bolt head. When in use, when the bolt is tightened in the right direction, the lower end face of the bolt head 4 is gently scratched from the ratchet back side. When the bolt is loosened in the left direction, the lower end face of the bolt head 4 is pressed against the ratchet tip. The ratchet teeth are positioned in the direction of loosening, facing the bolt head. During normal operation, any vibration-induced reverse rotation of the bolt, preventing it from loosening, is blocked by the teeth. However, this situation is different during manual disassembly. To loosen the bolt, a wrench is used to forcefully twist the bolt counterclockwise, causing it to rotate in the loosening direction. If the force is too great, the ratchet teeth will deform slightly, causing the bolt to retreat slightly. Continued force causes further deformation and further retreat, ultimately loosening the threads. This process, called "unlocking," is manually applied with a wrench. During normal operation, even vibration alone cannot naturally exert such a high loosening torque on the nut, preventing the mechanism from naturally unlocking. This is because the ratchet teeth resist, requiring significantly greater force to loosen the bolt than a standard nut. Therefore, the anti-loosening device is completely safe and reliable in use.

[0044] like Figure 7 、 8 As shown, the inner circle of the contact surface between the ratchet washer 8 and the bolt head 4 is provided with a chamfer. The chamfer can just make room for the transition arc 15 between the bolt head 4 and the bolt body 13, so that the ratchet washer 8 and the bolt head 4 have a better fit.

[0045] As an embodiment, the ratchet washer 8 is made of 65Mn and has a quenching and tempering hardness HRc of 40-52.

[0046] exist Figure 1 In the embodiment, the ratchet washer 8 is only one independent piece. It is not excluded that a pair of ratchet washers 8 are used to cooperate with each other.

[0047] The typical application of this utility model is the loosening of the oil box of the bearing bush of the railway motor. Figure 1During use, the bearing housing serves as the fastener 2, securing it to the motor body. Ratchet washer 8 is inserted into bolt body 13, which is then inserted into the through-hole of fastener 2 and screwed into the pre-set screw hole in motor body 1. After bolt 14 has been tightened to the preset torque, a pistol drill (with a drill bit diameter slightly smaller than the inner diameter of bolt screw hole 7) is used to drill a small hole in ratchet washer 8. This drill then penetrates and leaves a locking groove 3 in fastener 2. The taper angle and depth of locking groove 3 match those of the tail end of bolt screw 5. Once all bolt screws 5 are screwed into bolt screw holes 7 and their tail ends are firmly seated in locking groove 3, tie wire 10 is passed through the lashing hole 6 of bolt clamp head 9 and tightened, securing all bolt screws 5 together. This method secures bolt 14 to fastener 2 and motor body 1, preventing loosening despite continued vibration. Can be put into use immediately after installation. During disassembly, earlier the binding wire 10 is removed, and after unscrewing the bolt 5, the bolt 14 can be easily unloaded.

[0048] The above embodiments can be used interchangeably or simultaneously in actual applications. The above examples do not impose any form of limitation on the essential content of the utility model. Any simple modifications or deformations made by ordinary technicians in the relevant technical field to the above specific implementation methods based on the technical essence of the utility model after reading this specification, as well as equivalent embodiments that may be changed or modified into equivalent changes using the technical content disclosed above, still fall within the scope of protection of the technical solution of the utility model.

Claims

1. A single-head anti-loosening fastening device, characterized in that: The fastening device comprises a bolt (14) and a latching screw (5); The bolt (14) is provided with a cylindrical bolt body (13) with threads and a bolt head (4) integrally formed at the head, the circumscribed circle diameter of the bolt head (4) is 1.4 to 2.8 times the outer diameter of the bolt body (13), and the bolt head (4) is provided with two or more through and parallel bolt-clamping screw holes (7) in the axial direction of the non-overlapping portion with the bolt body, for threaded connection with the bolt-clamping screw (5); The bolt clamping screw (5) is coaxially and integrally provided with a bolt clamping head (9), a bolt clamping body (11) and a bolt clamping tail (12) in sequence in the axial direction. The bolt clamping body (11) is provided with an external thread. The diameter of the bolt clamping tail (12) shrinks towards the tail end and is used to be embedded in the locking groove (3) of the fastener in contact.

2. The single-head anti-loosening fastening device according to claim 1, characterized in that: A binding wire (10) is provided, and the bolt clamp head (9) is provided with a binding hole (6) perpendicular to the axial direction of the bolt clamp screw. The binding wire (10) passes through the binding hole (6) of each bolt clamp screw (5) in sequence and is fixed in a closed loop.

3. The single-head anti-loosening fastening device according to claim 1, characterized in that: An independent annular sheet-shaped ratchet washer (8) is provided. The ratchet washer (8) is sleeved outside the bolt body (13) and embedded between the bolt head (4) and the fastener (2). The end faces of both sides of the ratchet washer (8) are provided with annularly distributed ratchet teeth (16). The ratchet teeth (16) are formed by the intersection of the ratchet back side surface (17) and the ratchet front side surface (18) protruding from the washer body surface to form an acute angle.

4. The single-head anti-loosening fastening device according to claim 2, characterized in that: The cross section of the bolt clamp head (9) of the bolt clamp screw (5) is square, and the maximum outline perpendicular to the axial direction does not exceed the bolt clamp body (11), and the opening of the binding hole (6) is staggered with the square edge of the bolt clamp head (9).

5. The single-head anti-loosening fastening device according to claim 1, characterized in that: The tail end of the latching screw (5) is contracted to a 90° top angle.

6. The single-head anti-loosening fastening device according to claim 1, characterized in that: The bolt (5) is made of 35CrMoA quenched and tempered steel, and the quenched and tempered hardness of the tail end is HRc45-50.

7. The single-head anti-loosening fastening device according to claim 3, characterized in that: The angle between the back side surface (17) of the ratchet and the tightening direction of the bolt (14) is 20° to 30°, the angle between the front side surface (18) of the ratchet and the tightening direction of the bolt (14) is 80° to 95°, and the ratchet height is 2±0.5mm.

8. The single-head anti-loosening fastening device according to claim 3, characterized in that: The inner circle of the contact surface between the ratchet washer (8) and the bolt head (4) is provided with a chamfer (19).

9. The single-head anti-loosening fastening device according to claim 3, characterized in that: The ratchet washer (8) is made of 65Mn and has a quenching and tempering hardness of HRc40-52.

10. The single-head anti-loosening fastening device according to claim 3, characterized in that: The ratchet washer (8) is only one independent piece.

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