Novel pre-drilling-free board surface damage-free deck screw for hardwood

Abstract

The utility model discloses a novel deck screw used for hardwood and free of pre-drilling and damage to the surface of a wood board. The novel deck screw comprises a screwing head, a main body rod, a square conical tail, sawtooth threads and a chip guide groove. According to the screw, on one hand, in the process that the square cone tail is screwed into wood, compared with screws of the same type, the hole diameter is enlarged, and the situation that the surface of a high-density solid wood board cracks and tilts to form burrs due to the fact that the high-density solid wood board is affected by stress concentration is facilitated; on the other hand, the sawtooth threads are beneficial to smashing thick and large wood chip particles into fine wood chip particles, burrs and hard blocks in the hole diameter are removed in the screwing-in process, the situation that wood chips block the hole, the screwing-in difficulty is increased is avoided, meanwhile, more fine wood chip particles are adsorbed, the fastening degree of connection between the screw and the high-density solid wood board is improved, and the service life of the screw is prolonged. And the use stability of the high-density solid wood board is greatly improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of fastener, specifically relates to a deck screw for hard wood new type pre-drilling hole free surface of wood board free damage. BACKGROUND

[0002] Screw is a kind of commonly used fastener, it can be directly drilled into object, need not pre-opening hole.When drilling into object is high-density solid wood, thread will cause wood fiber to crack and form burr in the process of being screwed in, seriously endanger personnel safety, so need to regrind the surface of wood board, seriously improve cost. CONTENT OF UTILITY MODEL

[0003] The utility model discloses a deck screw for hard wood new type pre-drilling hole free surface of wood board free damage, a special sawtooth thread is designed at tail tip, solve the process that the deck nail screw is locked in high-density solid wood board in prior art needs to regrind the surface of wood board.

[0004] Technical scheme: a deck screw for hard wood new type pre-drilling hole free surface of wood board free damage, including screwing head, main body rod, square taper tail, sawtooth thread and chip removal groove;

[0005] The upper half of the main body rod is provided with first external thread and first chip removal groove, and the first external thread is spiral;The middle section of the main body rod is a smooth cylinder;The lower half of the main body rod is provided with second external thread and second chip removal groove, and the second external thread is spiral;A plurality of sawtooth threads are distributed on the second external thread;

[0006] The chip removal groove is connected to the top of the square taper tail, and the chip removal groove and the second chip removal groove are interconnected;

[0007] The screwing head drives the square taper tail at the bottom of the main body rod to be screwed down into wood, the square taper tail first enlarges the hole diameter to avoid the surface wood fiber cracking to form burr, and then cooperates with the sawtooth thread to accelerate the destruction of high-density solid wood fiber structure, to form fine wood particles along the spiral direction into the chip removal groove.

[0008] As optimization: the screwing head is provided with screwing groove.

[0009] As optimization: the first external thread is angle 30 ° tooth profile thread.

[0010] As optimization: the second external thread is angle 50 ° tooth profile thread.

[0011] As optimization: the sawtooth thread is angle 50 ° tooth profile thread.

[0012] As an optimization: the sawtooth thread thoroughly breaks up the burrs entering the chip guide groove to form fine wood chips, while removing hard lumps from the holes and improving the smoothness of the hole surface.

[0013] As an optimization: the first external thread continues to grind the surface of the hole with the downward axial force, so that it adsorbs more fine wood chips in the chip removal groove and the hole, making the connection between the high-density solid wood board and the screw more secure.

[0014] Beneficial effects: On the one hand, the square conical tail of this screw, compared with similar screws, enlarges the hole diameter during the screwing process into the wood, which helps to prevent stress concentration in the high-density solid wood board, thus preventing the surface of the high-density solid wood board from cracking, warping, and forming burrs. On the other hand, the serrated thread helps to break large wood chips into fine wood chips, and removes burrs and hard lumps from the hole during the screwing process, preventing wood chips from clogging the hole and increasing the difficulty of screwing in. At the same time, it adsorbs more fine wood chips, improves the tightness of the connection between the screw and the high-density solid wood board, and greatly improves the stability of the high-density solid wood board in use. Attached Figure Description

[0015] Fig. 1 This is a schematic diagram of the overall structure of this utility model;

[0016] Fig. 2 This is a cross-sectional structural diagram of the present invention;

[0017] Fig. 3 This is a partial structural schematic diagram of the present invention. Detailed Implementation

[0018] Example

[0019] like Figs. 1-3 As shown, a new type of deck screw for hardwood that requires no pre-drilling and does not damage the surface of the wood board includes a screwing head 1, a main body 2, a square conical tail 3, a serrated thread 4, and a chip guide groove 5. The screwing head 1 is provided with a screwing groove 11.

[0020] The upper half of the main body rod 2 is provided with a first external thread 21 and a first chip removal groove 22. The first external thread 21 is helical and has a 30° angle thread profile. The middle section of the main body rod 2 is a smooth cylinder. The lower half of the main body rod 2 is provided with a second external thread 23 and a second chip removal groove 24. The second external thread 23 is helical and has a 50° angle thread profile. Several sawtooth threads 4 are distributed on the second external thread 23, and the sawtooth threads 4 have a 50° angle thread profile.

[0021] The square conical tail 3 is provided with a chip guide groove 5 at the top.

[0022] The deck screw is driven by the driving head 1 to rotate the square conical tail 3 at the bottom of the main body rod 2 into the wood downward, the square conical tail 3 first expands the hole diameter to avoid the surface wood fiber cracking to form burrs, and then cooperates with the sawtooth thread 4 with an angle of 50° to accelerate the destruction of the high-density solid wood fiber structure, so that fine wood chip particles enter the chip guide groove 5 in the spiral direction; meanwhile, in the process of destroying the wood fiber structure, the fine wood chip burrs are adsorbed in the hole diameter and go upward along the chip groove, and finally accumulate on the surface of the solid wood board to form burr and edge lifting, and the sawtooth thread 4 fully crushes the burrs in the chip guide groove 5 to form fine wood chip particles, and at the same time, the small convexes in the hole are removed, the smoothness of the hole surface is improved, the wood chip is prevented from being blocked at the burr or small convex, and the rotation difficulty is increased. Finally, the first external thread 21 with a 30° tooth type continues to polish the hole surface with the downward axial force, so that more fine wood chip particles are adsorbed in the chip groove and the hole, the connection between the high-density solid wood board and the screw is more firm, and the stability of the high-density solid wood board is greatly improved.

[0023] The screw of the utility model on one hand expands the hole diameter in the process of rotating into the wood compared with the same type of screw, which is helpful for the high-density solid wood board to be affected by stress concentration, causing the surface of the high-density solid wood board to crack and form burrs; on the other hand, the sawtooth thread is helpful for crushing the coarse wood chip particles into fine wood chip particles, removing the burrs and small convexes in the hole diameter in the process of rotating in, preventing the wood chip from being blocked in the hole, increasing the rotation difficulty, and at the same time, adsorbing more fine wood chip particles, improving the fastening degree of the connection between the screw and the high-density solid wood board, and greatly improving the stability of the high-density solid wood board.

[0024] The above description clearly and completely describes the technical scheme in the embodiments of the utility model, so that the person skilled in the art can better understand the advantages and features of the utility model, and the protection scope of the utility model is more clearly defined. The embodiments described in the utility model are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.

Claims

1. A deck screw for hardwoods that is new and predrill free and surface damage free, characterized by: It comprises a screwing head (1), a main body rod (2), a square taper tail (3), a sawtooth thread (4) and a chip guide groove (5). The upper half of the main body rod (2) is provided with a first external thread (21) and a first chip guide groove (22), the first external thread (21) is helical; the middle section of the main body rod (2) is a smooth cylinder; the lower half of the main body rod (2) is provided with a second external thread (23) and a second chip guide groove (24), the second external thread (23) is helical; a plurality of sawtooth threads (4) are distributed on the second external thread (23); The top of the square taper tail (3) is connected with a chip guide groove (5), and the chip guide groove (5) and the second chip guide groove (24) are in communication with each other; The screwing head (1) drives the square taper tail (3) at the bottom of the main body rod (2) to screw down into the wood, the square taper tail (3) first expands the hole diameter to avoid the surface wood fiber cracking to form burrs, and then cooperates with the sawtooth thread (4) to accelerate the destruction of the high-density solid wood fiber structure, forming fine wood particles along the spiral direction into the chip guide groove (5).

2. The deck screw for hardwoods of claim 1, wherein: The screwing head (1) is provided with a screwing groove (11).

3. The deck screw for hardwoods of claim 1, wherein: The first external thread (21) is an angle 30° tooth type thread.

4. The deck screw for hardwoods of claim 1, wherein: The second external thread (23) is an angle 50° tooth type thread.

5. The deck screw for hardwoods that does not require pre-drilling and does not damage the surface of the wood plank according to claim 1, wherein: The sawtooth thread (4) is an angle 50° tooth type thread.

6. The deck screw for hardwoods that does not require pre-drilling and does not damage the surface of the wood plank according to claim 1, wherein: The sawtooth thread (4) fully stirs the burrs entering the chip guide groove (5) to form fine wood particles, and at the same time removes hard blocks in the hole, improving the smoothness of the hole surface.

7. The deck screw for hardwoods that does not require pre-drilling and does not damage the surface of the wood plank according to claim 1, wherein: The first external thread (21) continues to polish the hole surface with the downward axial force, so that more fine wood particles are adsorbed in the chip guide groove and the hole, and the connection between the high-density solid wood board and the screw is more firm.

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