An energy-saving self-tapping screw for high-altitude operations

Abstract

This invention proposes an energy-saving self-tapping screw for high-altitude operations, aiming to solve the problems of low positioning reliability, easy damage to fasteners, and insufficient pull-out resistance of existing self-tapping screws. It consists of a screw head, a screw shank, and a screw tail. The head has a tightening groove and a connecting section with reinforcing ribs. The shank has a smooth shank and a threaded section. The threaded section features alternating high and low threads, with the high thread having a sharp angle and a large diameter, and the low thread having a small diameter. First and second limiting protrusions are respectively provided between adjacent high and low threads. The tail end face has a V-shaped notched groove that extends inwards. The high and low threads work together to reduce torque and the risk of sheet metal breakage. The limiting protrusions enhance mechanical engagement, improving pull-out resistance and anti-loosening performance. The V-shaped groove efficiently removes chips, enabling rapid insertion. This invention offers efficient installation, reliable locking, reduces the number of times high-altitude re-tightening is required, and improves construction safety and efficiency. It is suitable for various self-tapping screw applications with different requirements.

Description

Technical Field

[0001] This utility model relates to the field of self-tapping screw technology, and in particular to an energy-saving locking self-tapping screw for high-altitude operations. Background Technology

[0002] The existing quick-acting self-tapping screws on the market have many technical defects in high-altitude operations and urgently need to be improved. Currently, when using an electric drill to assemble these screws, if the operator applies too much axial force or sets the electric drill speed too high, it is very easy to cause a series of construction quality problems.

[0003] The utility model authorized by announcement number CN202082238U relates to a "self-tapping screw", particularly a self-tapping screw with a guide. The self-tapping screw has a columnar guide portion at the head of its thread, with a tapered end. This addition of a columnar guide portion to the thread head of an existing self-tapping screw allows for easy insertion. During use, the cylindrical guide portion of the self-tapping screw is first driven in vertically with a hammer, and then the screw is screwed in with a screwdriver. This effectively solves the problem of axial misalignment when ordinary self-tapping screws are screwed into wooden components. Simultaneously, it strengthens the wood material through compression, ensuring the strength of the connection. This utility model features a reasonable structure, convenient installation and disassembly, and a firm connection. However, this utility model uses a single thread profile. In high-altitude operations, if the operator applies excessive axial force or sets the drill speed too high, positional shift and tilting may occur during insertion, leading to inaccurate tightening and difficulty in withstanding large pull-out forces.

[0004] In summary, existing self-tapping screws typically have the following disadvantages: 1) Low positioning reliability: Some existing quick-tapping self-tapping screws typically use continuous, single-start, and symmetrical tooth profiles. The cutting resistance is concentrated and released along a spiral line, and the torque peak increases instantaneously. When using an electric drill to assemble screws in high-altitude operations, if the operator applies excessive axial force or sets the electric drill speed too high, positional shift and tilt will occur during the tapping process, resulting in inaccurate fastening position. 2) Fasteners are easily damaged: When working at heights, if the operator applies excessive driving torque during the application of axial force, some existing self-tapping screws may cause damage to the surface of the fastened parts, seriously affecting the structural integrity. 3) Insufficient pull-out resistance: Screws in high-altitude environments need to withstand greater pull-out forces, but the thread structure design of some existing self-tapping screws is not able to withstand large pull-out forces, which may pose a safety hazard. Summary of the Invention

[0005] The purpose of this invention is to solve the problems in the prior art by proposing an energy-saving self-tapping screw for high-altitude operations, which can solve the problems of low positioning reliability, easy damage to fasteners, and insufficient pull-out force.

[0006] To achieve the above objectives, this utility model proposes an energy-saving self-tapping screw for high-altitude operations, comprising a screw head, a screw shank, and a screw tail. The screw head includes a nut and a connecting section. The top surface of the screw head has an inwardly recessed tightening groove. The bottom end of the screw head is fixedly connected to the connecting section, which has several reinforcing ribs. The bottom end of the connecting section is connected to the screw shank. The screw shank includes a smooth section and a threaded section. The threaded section has axially alternating first and second threads. The outer diameter of the first thread is larger than the outer diameter of the second thread. A first limiting protrusion is provided between two adjacent first threads, and a second limiting protrusion is provided between two adjacent second threads. The end face of the screw tail has at least one V-shaped notched groove penetrating the end face. The width of the V-shaped notched groove gradually decreases from the end face towards the screw shank, and the two side walls of the V-shaped notched groove extend symmetrically in a V-shape.

[0007] Preferably, the smooth rod portion and the threaded portion are integrally formed, the tooth profile angle of the first thread is an acute angle, and the first thread and the second thread are equidistant from each other along the axial direction of the screw rod.

[0008] Preferably, the first limiting protrusion protrudes outward in a radial direction, and the two circumferential ends of the first limiting protrusion are connected to the tooth sides of two adjacent first threads. The height of the top surface of the first limiting protrusion is less than the height of the tooth crest of the first thread.

[0009] Preferably, the upper end of the second limiting protrusion is connected to the tooth side of a second thread, the lower end of the second limiting protrusion extends to the bottom of the adjacent second thread, the bottom surface of the second limiting protrusion forms a radial step with the outer peripheral surface of the screw shank, and the height of the top surface of the second limiting protrusion is greater than the tooth crest height of the second thread.

[0010] Preferably, the tightening groove is one of a cross shape, a star shape, or an internal hexagon.

[0011] Preferably, the outer peripheral surface of the connecting section is provided with a beveled surface that transitions in a tapered shape around the axis, and a number of radially extending reinforcing ribs are provided between the beveled surface and the nut.

[0012] The beneficial effects of this utility model are: 1) Overall performance improvement: The high and low tooth staggered double thread structure adopts a large outer diameter and sharp angle high thread design, which significantly reduces rotational torque and tapping resistance, improves self-tapping efficiency, and reduces the risk of plate breakage; at the same time, the high and low tooth cooperative structure design allows the high thread to cut the material quickly, while the low thread can accommodate and tighten the debris, enhance the friction and locking force between the thread and the plate, improve the pull-out strength, and ensure that it will not loosen during long-term use; 2) Stable and reliable: The rectangular protrusion limiting structure of the threaded ring sets a rectangular protrusion on the threaded ring, with adjacent high or low teeth as the limiting boundary, which enhances the mechanical engagement between the thread and the plate, making the connection more secure and preventing it from coming off. This structure also has a limiting and locking function, effectively suppressing screw loosening and improving stability in high-altitude vibration environments. 3) Easy installation: The V-shaped notched groove at the tail of the screw allows for quick cutting of the board and chip removal during insertion, greatly improving the insertion speed, optimizing self-tapping performance, and making installation more efficient.

[0013] The features and advantages of this utility model will be described in detail through embodiments and accompanying drawings. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 yes Figure 1 Enlarged schematic diagram of the threaded portion; Figure 3 yes Figure 1 Enlarged schematic diagram of the screw tail; Figure 4 This is a top view of the present invention.

[0015] The numbers in the diagram are: 1-Screw head; 2-Nut; 3-Connecting section; 21-Tightening groove; 3-Connecting section; 31-Bevel; 32-Reinforcing rib; 4-Screw shank; 5-Smooth shank; 6-Threaded section; 61-First thread; 62-Second thread; 63-First limiting protrusion; 64-Second limiting protrusion; 65-Step; 7-Screw tail; 71-V-shaped missing tooth groove. Detailed Implementation

[0016] Example 1: See Figures 1 to 4 This utility model discloses an energy-saving self-tapping screw for high-altitude operations, comprising a screw head 1, a screw shank 4, and a screw tail 7. The screw head 1 includes a nut 2 and a connecting section 3, as shown below. Figure 1 As shown, the top surface of the screw head 1 is provided with an inwardly recessed tightening groove 21, and the bottom end of the screw head 1 is fixedly connected to a connecting section 3. The connecting section 3 is provided with several reinforcing ribs 32, and the bottom end of the connecting section 3 is connected to the screw shank 4. The screw shank 4 includes a smooth shank portion 5 and a threaded portion 6, as shown. Figure 2 As shown, the threaded portion 6 is provided with axially alternating first threads 61 and second threads 62. The outer diameter of the first thread 61 is larger than the outer diameter of the second thread 62. A first limiting protrusion 63 is provided between two adjacent first threads 61, and a second limiting protrusion 64 is provided between two adjacent second threads 62; Figure 3As shown, at least one V-shaped notched groove 71 is provided on the end face of the screw tail 7, which runs through the end face. The width of the groove opening of the V-shaped notched groove 71 gradually decreases from the end face to the screw rod 4, and the two side walls of the V-shaped notched groove 71 extend symmetrically in a V shape.

[0017] The smooth rod portion 5 and the threaded portion 6 are integrally formed. The tooth angle of the first thread 61 is an acute angle. The first thread 61 and the second thread 62 are equidistant along the axial direction of the screw rod 4. The first limiting protrusion 63 protrudes radially outward. The two circumferential ends of the first limiting protrusion 63 are connected to the tooth sides of two adjacent first threads 61. The top surface height of the first limiting protrusion 63 is less than the tooth crest height of the first thread 61. The upper end of the second limiting protrusion 64 is connected to the tooth side of a second thread 62. The lower end of the second limiting protrusion 64 extends to below the adjacent second thread 62. The bottom surface of the second limiting protrusion 64 forms a radial step 65 with the outer circumferential surface of the screw rod 4. The top surface height of the second limiting protrusion 64 is greater than the tooth crest height of the second thread 62. Figure 4 As shown, the tightening groove 21 is one of a cross shape, a star shape, or an internal hexagon; the outer peripheral surface of the connecting section 3 is provided with a bevel 31 that transitions in a conical shape around the axis, and a number of radially extending reinforcing ribs 32 are provided between the bevel 31 and the nut 2.

[0018] In this embodiment, the nut 2 has a conventional hexagonal outer edge, and the tightening groove 21 adopts a cross-shaped countersunk hole; the outer periphery of the connecting section 3 is provided with a continuous conical bevel 31, and six radial reinforcing ribs 32 are evenly distributed; the threaded part 6 has alternating threads of unequal height; the first limiting protrusion 63 and the second limiting protrusion 64 are both rectangular protrusions, and the end face of the tail 7 has a through-type V-shaped missing tooth groove 71. The whole is made of SUS410 martensitic stainless steel material, which is quenched and tempered. The screw in this embodiment is easy to drive in, reliable to lock, and highly corrosion resistant. It is especially suitable for rapid installation on high-altitude metal roofs along the coast. It can be locked in one screwing, reducing the number of times to tighten at high altitudes.

[0019] Example 2: This embodiment is basically the same as Embodiment 1, except that: the first limiting protrusion 63 adopts a spiral cutting edge, which extends continuously along the tooth side of the first thread 61 to form a short-pitch secondary thread; the second limiting protrusion 64 adopts a barbed ratchet, which is inclined towards the tail along the tooth back of the second thread 62 and has a sharp end; the spiral cutting edge performs secondary cutting like a fine tap when it is driven in, which significantly reduces the peak torque, while the barbed ratchet is driven into the hole wall in the opposite direction after being screwed in, forming a one-way anti-reverse. The whole assembly does not require any additional parts, and can achieve the effect of tightening more and more in the high-altitude locking of thin steel plates, reducing re-tightening.

[0020] Example 3: This embodiment is basically the same as embodiment 1, except that the original single V-shaped missing tooth groove 71 is replaced with a double V-shaped cross groove. The two V-shaped grooves are arranged at a 90° angle to each other on the end face of the screw tail 7. The groove width still gradually decreases from the end face inward. The double V-shaped cross groove forms four cutting edges, increasing the chip removal area and further reducing the driving resistance. At the same time, the cross structure gives the tail better radial elasticity. After screwing in, the groove wall opens slightly outward, providing additional mechanical locking. It is suitable for hardwood high-altitude walkways, achieving rapid driving and reliable anti-loosening without the need for pre-drilling.

[0021] Working principle: First, the operator aligns the screwdriver tip with the tightening groove 21 on the top surface of the screw head 1 and applies torque. Under the action of torque, the screw shank 4 rotates while tapping into the hole of the substrate, and the screw tail 7 contacts the substrate first. The V-shaped notched groove 71 divides the end face into several elastic petals that can shrink radially towards the center, so that the outer diameter of the tail end is reduced immediately, achieving low resistance introduction. As it goes deeper, the threaded part 6 begins to participate in cutting and forming: the first thread 61 taps out the main thread groove with a larger outer diameter, providing the main bearing tooth profile, and the second thread 62 performs secondary finishing on the groove formed with a smaller outer diameter, reducing the resistance of the remaining material and improving the surface quality of the thread. The first thread 61 and the second thread 62, which are arranged alternately in the axis, form a main-secondary double diameter structure, which disperses the peak of the tapping torque while ensuring the connection strength, achieving an energy-saving effect. When the screw reaches the predetermined depth, the two work together to form a locking-anti-loosening double limit mechanism to resist loosening caused by high-altitude vibration. The nut 2 is pressed against the surface of the connected part by the tapered inclined surface 31 and the reinforcing rib 32 on the connecting section 3, forming a surface-to-surface contact seal.

[0022] The above embodiments are illustrative of the present invention and are not intended to limit the present invention. Any simple modifications to the present invention are within the protection scope of the present invention.

Claims

1. An energy-saving self-tapping screw for high-altitude operations, comprising a screw head (1), a screw shank (4), and a screw tail (7), characterized in that: The screw head (1) includes a nut (2) and a connecting section (3). The top surface of the screw head (1) is provided with an inwardly recessed tightening groove (21). The bottom end of the screw head (1) is fixedly connected to the connecting section (3). The connecting section (3) is provided with several reinforcing ribs (32). The bottom end of the connecting section (3) is connected to the screw rod (4). The screw rod (4) includes a smooth rod part (5) and a threaded part (6). The threaded part (6) is provided with an axially alternating first thread (61) and a second thread (62). The outer diameter of the first thread (61) is larger than the outer diameter of the second thread (62). A first limiting protrusion (63) is provided between two adjacent first threads (61), and a second limiting protrusion (64) is provided between two adjacent second threads (62). At least one V-shaped toothed groove (71) is provided on the end face of the screw tail (7). The width of the groove opening of the V-shaped toothed groove (71) gradually decreases from the end face to the screw rod (4). The two sides of the groove wall of the V-shaped toothed groove (71) extend symmetrically in a V shape.

2. The energy-saving self-tapping screw for high-altitude operations as described in claim 1, characterized in that: The smooth rod part (5) and the threaded part (6) are integrally formed structures. The tooth angle of the first thread (61) is an acute angle. The first thread (61) and the second thread (62) are equidistant along the axial direction of the screw rod (4).

3. The energy-saving self-tapping screw for high-altitude operations as described in claim 1, characterized in that: The first limiting protrusion (63) protrudes outward in the radial direction. The two circumferential ends of the first limiting protrusion (63) are connected to the tooth sides of the two adjacent first threads (61). The height of the top surface of the first limiting protrusion (63) is less than the height of the tooth crest of the first thread (61).

4. The energy-saving self-tapping screw for high-altitude operations as described in claim 1, characterized in that: The upper end of the second limiting protrusion (64) is connected to the tooth side of a second thread (62), the lower end of the second limiting protrusion (64) extends to the bottom of the adjacent second thread (62), the bottom surface of the second limiting protrusion (64) forms a radial step (65) with the outer peripheral surface of the screw rod (4), and the height of the top surface of the second limiting protrusion (64) is greater than the tooth crest height of the second thread (62).

5. The energy-saving self-tapping screw for high-altitude operations as described in claim 1, characterized in that: The tightening groove (21) is one of the following: cross-shaped, star-shaped, or internal hexagonal.

6. The energy-saving self-tapping screw for high-altitude operations as described in claim 1, characterized in that: The outer peripheral surface of the connecting section (3) is provided with a bevel (31) that is tapered around the axis, and a number of radially extending reinforcing ribs (32) are provided between the bevel (31) and the nut (2).

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