TWI408292B - Screw - Google Patents

Abstract

The present invention relates to a screw including a shank and a thread formed on the shank. The shank has an insertion end. The thread is in the helical form surrounding an outer circumference of the shank and includes a plurality of convolutions each having a front flank facing the insertion end and a rear flank facing away from the insertion end. The screw further includes at least one groove. The groove is formed on the outer circumference of the shank and extends helically along a bottom edge of one of the front and rear flanks of each convolution of the thread. The groove is adapted for receiving chippings produced when the screw is screwed into articles which need to be interlocked together, so that the screwing speed of the screw can be enhanced. Further, the groove can be used for enhancing the interlocking function of the screw.

Description

Screw

The present invention provides a screw, and more particularly a screw suitable for use in wood, building materials or the like.

On wood objects including furniture, decoration and construction, wood is used in large quantities or composite wood made of plastic resin and wood chips. The connection between the wooden objects is usually locked by a screw having an insertion end at the end, the screw comprising a rod and at least one thread wound around the rod, so that the screw is rotatably screwed into the locked to be connected Within the compound. Furthermore, in order to increase the speed at which the screw is locked into the interlocking compound, for example, the design of the groove on the shaft of the screw or the crest of the thread has been proposed to collect or accommodate the residue. Chips. To be clear, when the screw thread is screwed into the lock compound, the wood is cut to produce debris (wood chips), and the groove can be used to contain debris, so that the screw is less likely to be trapped during the locking process. It is also hindered and the lock compound is less likely to crack. However, the conventional groove for accommodating the debris extends in the longitudinal direction of the screw shaft and intersects the thread of the screw, which is not only cumbersome to manufacture but also does not contribute to the bonding ability of the screw; likewise, the thread peak of the thread ( The groove is provided on the crest to accommodate the debris, and the coupling ability of the screw is not substantially helpful. In addition, the groove provided on the screw peak can accommodate a limited amount of debris.

Accordingly, it is an object of the present invention to provide a screw suitable for use in wood or building materials, the screw having a groove for receiving debris, so that the screw can be smoothly screwed into the interlocking compound, and the groove has It is easy to manufacture and can improve the bonding force between the screw and the lock compound.

A screw constructed in accordance with the present invention includes a shaft, at least one thread disposed on the shaft, and a first groove. The shaft includes an outer periphery and an insertion end and a head end spaced apart on a longitudinal axis, the insertion end forming a drill bit pattern. The thread is helically wound around the outer periphery of the shaft, the thread comprising a plurality of threads, each thread having a front screw facing the insertion end and a rear screw facing away from the insertion end. The first groove is disposed at an outer periphery of the rod body and spirally extends along a bottom edge of one of a screw nose and a rear screw body of the screw thread of the thread.

In a preferred embodiment, the screw further includes a second groove disposed around the outer periphery of the rod and spirally along the thread of the thread before the screw or the back screw The bottom edge of the other one extends. The rod body has a straight section between the insertion end and the head end, and the rod body further includes a longitudinal slit extending from the insertion end toward the head end for a length, the first groove and the first groove The second groove is wound in parallel on a straight section between the upper end of the slot of the rod and the head end.

The first groove is recessed along a radial direction of the rod by a first depth, the first depth preferably being 10-25% of the height of the screw; the second groove is along a radial direction of the rod The recess is recessed to a second depth which is preferably 10-25% of the height of the thread.

Preferably, the cross section of the first trench and the second trench are U-shaped or V-shaped.

Other objects, advantages and features of the present invention will become apparent from

The preferred structural aspects of the present invention will now be described by way of example only, and not by way of limitation,

The first to fifth figures show a screw 10 constructed in accordance with a preferred embodiment of the present invention. The screw 10 includes a shaft 12 and a thread 14 disposed on the shaft 12. The shaft 12 includes an outer periphery (root) 15 and an insertion end 16 and a head end 18 spaced apart on a longitudinal axis. The insertion end 16 forms a drill bit pattern. In the present embodiment, the shaft 12 further includes a slot 20 extending a length from the insertion end 16 toward the head end 18. The outer diameter of the head end 18 is larger than the diameter of the shaft 12, and the upper surface of the head end 18 has a bearing hole 22 for insertion by a driver (not shown). Furthermore, the shaft 12 has a straight section 23 of equal outer diameter between the insertion end 16 and the head end 18.

The thread 14 is helically disposed on the outer periphery 15 of the shaft 12 and extends from the insertion end 16 toward the head end 18. In the present embodiment, the thread 14 is looped between the insertion end 16 and the head end 18. The thread 14 includes a plurality of threads 24, each thread 24 having a height of thread 26 and a substantially equal pitch between adjacent two threads 24. Furthermore, each of the threads 24 of the thread 14 has a front flank 28 on the locking side (i.e. facing the insertion end 16) and a rear flank 30 on the exit side (backward insertion end 16).

In the embodiment, the screw 10 of the present invention further includes a first groove 32 and a second groove 34. The first groove 32 is disposed at the outer periphery 15 of the rod body 12 and spirally extends along the bottom edge of the screw nose 28 of the thread 24 of the thread 14 , and the second groove 34 is disposed on the rod body 12 . The outer periphery 15 extends helically along the bottom edge of the thread 30 of the thread 24 of the thread 14. Preferably, the first groove 32 and the second groove 34 are wound in parallel on the straight section 23 between the upper end of the slot 20 of the rod 12 and the head end 18; further, the first groove The cross section of the second groove 34 and the second groove 34 is U-shaped, that is, the first groove 32 and the second groove 34 have a concave surface 36 having a circular arc shape (see the third figure). However, in another preferred embodiment, the first trench 32 and the second trench 34 have a V-shaped cross section.

The screw 10 of the present invention, in implementation (see Figure 5), is locked into the two interlocking compounds 38, 40, such as wood, with the insertion end 16. When the insertion end 16 of the screw 10 is screwed into the lock compound 38, 40, the thread 14 and the slot 20 of the insertion end 16 will cut the lock compound 38, 40 and the debris 42 will be generated. The generated debris 42 will be squeezed into the first groove 32 and the second groove 34, so that the resistance of the screw 10 in the locking direction is reduced, thereby increasing the screwing speed, and the locking compound 38, 40 It is also less prone to rupture. Furthermore, the first groove 32 and the second groove 34 are disposed and can strengthen the bonding force between the screw 10 and the lock compound 38, 40. Specifically, the first and second grooves 32, 34 are Individually spirally extending along the bottom edges of the thread 24 of the thread 14 before and after the threaded webs 28, 30 such that the threaded teeth 24 of the thread 14 have a larger diameter in the radial direction. length. Therefore, when the screw 10 is locked into the lock compound 38, 40, the nip area between the thread 14 of the screw 10 and the lock compound 38, 40 is increased, and the effect of increasing the locking force of the screw 10 is achieved. In addition, the first groove 32 and the second groove 34 extend in a spiral shape along the bottom edge of the screw 24 of the thread 14 and the bottom edge of the rear screw body 28, 30. Therefore, the first groove 32 and the first groove 32 The two grooves 34 are relatively convenient to manufacture and can reduce manufacturing costs.

In the present embodiment, the first groove 32 is recessed along the radial direction of the rod 12 by a first depth 44 which is approximately equal to 10-25% of the screw height 26. The second groove 34 is recessed along the radial direction of the shaft 12 by a second depth 46 which is approximately equal to 10-25% of the screw height 26. When the first and second depths 44, 46 are greater than 10% of the screw height 26, the effect of accommodating the debris 42 is better, and when the first and second depths 44, 46 are greater than 25% of the screw height 26, This will negatively affect the structural strength of the shaft 12.

It is understood that the screw 10 of the present invention may comprise only the first groove 32 or the second groove 34. In addition, please understand that the first trench 32 and the second trench 34 disposed on the rod 12 are not limited to a single continuous spiral groove; in a feasible embodiment, the first trench 32 may be a plurality of discontinuous A trench segment is formed, and the second trench 34 can be composed of a plurality of discontinuous second trench segments.

In the foregoing specification, the invention has been described in terms of a particular embodiment, and various changes or modifications may be Therefore, obvious substitutions and modifications may be made by those skilled in the art, and will still be incorporated in the scope of the claimed invention.

10. . . Screw

12. . . Rod body

14. . . Thread

15. . . Outer circumference

16. . . Insertion end

18. . . Head end

20. . . Grooving

twenty two. . . Hole

twenty three. . . Straight section

twenty four. . . Screw

26. . . Screw height

28. . . Front snail

30. . . Posterior

32. . . First groove

34. . . Second groove

36. . . Concave surface

38.40. . . Locked complex

42. . . Scrap

44. . . First depth

46. . . Second depth

The first figure is a perspective view of a screw constructed in accordance with an embodiment of the present invention.

The second figure shows a plan view of the screw of the first figure.

The third figure shows a partially enlarged plan view of the screw of the second figure.

The fourth figure shows a partial enlarged cross-sectional view of the screw of the second figure.

The fifth figure shows a schematic view of the screw-bonded two-locked compound of the first figure.

10. . . Screw

12. . . Rod body

14. . . Thread

15. . . Outer circumference

16. . . Insertion end

18. . . Head end

20. . . Grooving

twenty three. . . Straight section

twenty four. . . Screw

28. . . Front snail

30. . . Posterior

32. . . First groove

34. . . Second groove

Claims (4)

A screw comprising: a rod body comprising an outer periphery and an insertion end and a head end spaced apart on a longitudinal axis, the insertion end forming a drill bit type; a thread wound in a spiral shape around the rod The outer circumference of the body, the thread includes a plurality of threaded teeth, each thread has a front screw belly facing the insertion end and a rear screw belly facing the insertion end; and a first groove disposed outside the rod body Surroundingly and spirally extending along a bottom edge of one of the screw front and the rear screw front of the thread of the thread; wherein each thread has a thread height, the first groove along The rod is radially recessed to a first depth which is 10-25% of the height of the thread. A screw according to the first aspect of the patent application, wherein the first groove has a U-shaped or V-shaped cross section. According to the screw of the first aspect of the patent application, a second spiral groove is further disposed, and the second groove is disposed around the outer periphery of the rod and spirally follows the screw and the back screw of the screw thread of the thread. a bottom edge of the other of the abdomen; wherein each of the threads has a thread height, the second groove is recessed along a radial direction of the rod to a second depth, the second depth being the height of the thread 10-25%. According to the screw of item 3 of the patent application, wherein the first groove and the first The cross section of the two grooves is U-shaped or V-shaped.