TWM547605U - Screw with cutting thread - Google Patents

Description

Screw with cutting teeth

The present invention relates to a screw suitable for a wood workpiece or a cement workpiece, and more particularly to a screw having a cutting tooth.

On wooden workpieces 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 workpieces is usually locked by screws. Conventional screws generally include a rod and a thread wound around the rod, which are screwed into the two workpieces so that the two workpieces can be screwed together. However, when the material of the wooden workpiece is very hard, the thread of the conventional screw generates considerable frictional resistance during the reaming process of screwing into the workpiece, which is laborious and time consuming to operate, and is liable to cause cracking of the workpiece. Moreover, when the screw is applied to a hard cement workpiece, it also has the problem of laborious operation and slow screwing speed.

Accordingly, the main object of the present invention is to provide a screw having a cutting tooth which can be quite smooth during the reaming process of screwing into the workpiece, and has the effect of high screwing speed and low effort, and does not reduce the effect. The bonding force between the screw and the workpiece prevents cracking of the workpiece.

The screw of the present invention comprises a rod body and a thread, the rod body comprising a front section, a rear section and an intermediate section between the front section and the rear section, the upper end of the rear section forming a head, the front section and the front section The rear section is separated by a longitudinal axis of the shaft, the intermediate section having a circular transverse section, the front section having a generally triangular transverse section, and the front section being provided with a plurality of spaced apart teeth. The thread is wound around the shaft and includes a plurality of threads, and a pitch is defined between adjacent two threads. The front section extends along the longitudinal axis of the shaft for at least two pitch lengths, each of the protruding teeth projecting outwardly from the periphery of the front section and positioned between adjacent two threads, each of the teeth being along the rod The longitudinal axis extends for at least one pitch length.

In one embodiment, the front section includes an upper portion adjacent the intermediate section and a lower portion spaced from the upper portion at the longitudinal axis, the lower portion extending along at least one pitch of the longitudinal axis of the shaft, and the plurality of convexities The tooth is disposed at a lower portion of the front portion, and the upper portion is between the lower portion and the intermediate portion and no protrusion is disposed around the upper portion. The lower portion of the front section is provided with three spaced apart teeth, and the tips of the respective teeth are pointed and protruded outwardly to a height smaller than the height of the thread.

In an embodiment, the front section has three arcuate corners spaced apart, the three arc angles being staggered with the three teeth. In another embodiment, the three dentitions are individually overlapped with the three arcuate angles.

In an embodiment, the lower portion of the front section extends a drill tail end having a triangular cross section, the drill tail end having three sharp corners, the three sharp corners and the three circles of the front section The arc angles are staggered or aligned on the longitudinal axis.

In an embodiment, the rod diameter of the intermediate section is larger than the rod diameter of the front section, and the tips of the plurality of teeth define a convex outer diameter, and the convex outer diameter is larger than the rod diameter of the intermediate section. The rear section is provided with a plurality of spaced ribs, and the angle between each rib and the longitudinal axis is between 10-30 degrees.

Other objects, advantages and features of the present invention will be apparent from the description of the appended claims appended claims

The preferred embodiment of the present invention will now be described by way of example only, but not by way of limitation,

Referring to Figures 1 through 7, there is shown a screw 10 constructed in accordance with a first embodiment of the present invention. The screw 10 includes a shaft 12 that includes a front section 14, a rear section 16, and a position between the front section 14 and the rear section 16. An intermediate segment of 18. The front section 14 and the rear section 16 are separated by a longitudinal axis (X) of the shaft 12. In the present embodiment, the lower end of the front section 14 extends a tapered tapered end 20 having a triangular cross section, and the screw 10 having the trailing end 20 is adapted for screwing into a workpiece such as wood. In another embodiment, the lower end of the front section 14 does not have a trailing end (see Figure 9), and the screw 10 without the trailing end is suitable for screwing into a workpiece such as cement (the cement workpiece has been pre-drilled).

The intermediate section 18 and the rear section 16 have a circular cross section and the outer diameter of the rear section 16 is slightly larger than the outer diameter of the intermediate section 18. The upper end of the rear section 16 has a head 22 having an upper surface 24 for insertion of a driver (not shown). The screw 10 further includes a thread 26 that is helically disposed on the shaft 12 and includes a plurality of threads 28 with a pitch (P) between adjacent two threads 28. In the present embodiment, the threads 26 extend from the drill tail end 20 to the intermediate section 18, and in the embodiment illustrated in Figure 9, the threads 26 extend from the front section 14 to the intermediate section 18. In a possible embodiment, the threads 26 can extend from the front section 14 to the rear section 16.

The present invention is characterized in that the front section 14 of the screw 10 is designed to have a substantially triangular cross section, and a plurality of spaced apart teeth 30 are provided around the front section 14, each of the teeth 30 being around the front section 14. Protruding outwardly and positioned between adjacent two threads 28, the height of each of the teeth 30 projecting outward is smaller than the height of the teeth 28 (see Fig. 2). In the present embodiment, the tips of the respective teeth 30 are pointed, so that the lateral cross sections of the respective teeth 30 are saw-toothed (see Fig. 6). Furthermore, the front section 14 includes a lower portion 32 adjacent the drill tail end 20 and an upper portion 34 adjacent the intermediate section 18. In the present embodiment, the axial length (L) of the front section 14 is about four pitches (P), and the crown 30 The length of the lower portion 32 of the front section 14 and extending in the longitudinal axis (X) direction is about two pitches (P), and the upper portion 34 between the lower portion 32 and the intermediate portion 18 is not provided with the teeth 30, and the upper portion 34 is The length extending in the longitudinal axis (X) direction is approximately two pitches (P).

In the present embodiment, the circumference of the front section 14 has three arc angles 36 (see FIG. 6) separated by about 120 degrees, and the front section 14 is provided with three teeth 30 separated by about 120 degrees, the three protrusions. The teeth 30 are offset from the three arcuate angles 36. However, in another embodiment, each of the teeth 30 is overlapped by a corresponding arcuate angle 36 and is within a range defined by the two tangent lines 38 extending from the corresponding arcuate angle 36 (see Figures 8 and 8a). . Furthermore, the drill tail end 20 has a triangular cross section (see FIG. 7). In the present embodiment, the drill tail end 20 has three sharp corners 40, and the three sharp corners 40 and the front circle 14 have three circles. The arc angle 36 is staggered on the longitudinal axis (X). However, in a possible embodiment, the three sharp corners 40 of the drill tail end 20 are aligned with the three arcuate corners 36 of the front section 14 on the longitudinal axis (X).

In the present embodiment, the thread 28 in the intermediate section 18 has the same circular cross-section as the shaft, while the thread 28 in the front section 14 and the trailing end 20 has the same triangular cross-section as the shaft. Furthermore, the rod diameter of the rod body 12 gradually increases from the drill tail end 20 to the rear section 16, that is, the rod diameter D1 of the rear section 16 is larger than the rod diameter D2 of the intermediate section 18, and the rod diameter D2 of the intermediate section 18 is larger than the front section 14 The rod diameter D3, the rod diameter D3 of the front section 14 is larger than the rod diameter of the drill tail end 20, and the tip end of the convex tooth 30 provided at the front section 14 defines a convex outer diameter D4 (see Fig. 3), the convex outer diameter D4 is larger than The rod diameter D3 of the front section 14 and the rod diameter D2 of the intermediate section 18, according to which the screw 10 can reduce the contact area with the workpiece when locked into the workpiece (the coating on the surface can also prevent the coating from being damaged), In turn, the screwing resistance is reduced and the anti-rotation effect is improved.

In the present embodiment, the rear section 16 is provided with a plurality of spaced apart ribs 42. The angle (A) of each of the ribs 42 and the longitudinal axis (X) is between 10 and 30 degrees, and the number of ribs 42 is defined. An outer diameter D5 (see Fig. 3), the outer diameter D5 being greater than the rod diameter D1 of the rear section 16 to facilitate the insertion of the rear section 16 into the workpiece.

The screw 10 of the first embodiment of the present invention is implemented by inserting the drill tail end 20 into a workpiece such as a wooden board, and inserting the through hole 24 of the head 22 with a hand tool or a power tool (not shown) to turn the screw 10 The three sharp corners 40 of the drill tail end 20 are initially cut and reamed by the workpiece, and the thread 26 is screwed into the workpiece. During the reaming of the thread 26 into the workpiece, the frictional resistance of the reaming can be reduced by the small contact area of the front section 14 of the triangular section with the workpiece, and the teeth 30 around the front section 14 can assist the thread 26 to cut. The workpiece is such that the resistance of the screw 10 in the locking direction is effectively reduced, thereby increasing the screwing speed; in addition, the waste generated by cutting the workpiece can be discharged along the space around the front section 14 of the triangular section to reduce the resistance when the debris is discharged. So that the screw itself will not break and the workpiece will not break. Furthermore, when the screw 10 screwed into the workpiece will reach the intermediate section 18 of the circular section from the front section 14 of the triangular section, the buffer zone is formed by the upper portion 34 where the crown 30 is not provided, so that the intermediate section 18 of the circular section It can also be smoothly screwed into the object, and the screw 10 is quite smooth in the whole process of the lock, so that the operation is labor-saving and time-saving. Further, since the intermediate portion 18 of the screw 10 has a circular cross section, the crest of the thread 26 can exert a high-strength biting force on a workpiece such as wood to achieve an effect of improving the bonding strength. The above-mentioned effects can also be achieved by the screw 10 (see FIG. 9) of the second embodiment of the present invention. Specifically, when the screw 10 of the second embodiment is screwed into the cement workpiece, the front section 14 of the triangular section can be utilized. The effect of cutting and reaming is achieved by matching a plurality of teeth 30 around the front section 14.

The above description of the preferred embodiments of the present invention is not intended to limit the scope of the present invention, and the scope of the invention should be limited to the following claims. And the approximate structure should be included in the new model.

10‧‧‧ screws
12‧‧‧ rod body

14‧‧‧
16‧‧‧After

18‧‧‧ Middle section
20‧‧‧Drilling end

22‧‧‧ head
24‧‧‧ hole

26‧‧‧ thread
28‧‧‧ threaded teeth

30‧‧ ‧ convex teeth
32‧‧‧ lower

34‧‧‧ upper
36‧‧‧Arc angle

38‧‧‧ Tangent
40‧‧‧ sharp corner

42‧‧‧ ribs

1 is a perspective view of a screw of an embodiment of the present invention.

Figure 2 shows a front view of the screw of Figure 1.

Figure 3 is a longitudinal cross-sectional view taken along line 3-3 of Figure 1.

Figure 4 is a transverse cross-sectional view taken along line 4-4 of Figure 2.

Figure 5 is a cross-sectional view taken along line 5-5 of Figure 2.

Figure 6 is a cross-sectional view taken along line 6-6 of Figure 2.

Figure 7 is a cross-sectional view taken along line 7-7 of Figure 2.

Figure 8 is a cross-sectional view similar to Figure 6 showing another embodiment of the presently disclosed crown.

Figure 8a is a partial enlarged view of Figure 8.

Figure 9 is a front elevational view of the screw of another embodiment of the present invention.

10‧‧‧ screws

12‧‧‧ rod body

14‧‧‧

16‧‧‧After

18‧‧‧ Middle section

20‧‧‧Drilling end

22‧‧‧ head

26‧‧‧ thread

28‧‧‧ threaded teeth

30‧‧ ‧ convex teeth

32‧‧‧ lower

34‧‧‧ upper

42‧‧‧ ribs

Claims (9)

A screw having a cutting tooth, comprising: a rod body including a front section, a rear section and an intermediate section between the front section and the rear section, the upper end of the rear section forming a head portion, the front section and the rear section Separating a longitudinal axis of the shaft, the intermediate section having a circular transverse section, the front section having a generally triangular transverse section, the front section being provided with a plurality of spaced apart teeth; and a thread Provided on the rod body and comprising a plurality of threaded teeth, a pitch defined between adjacent two threads, wherein the front section extends along the longitudinal axis of the rod body by at least two pitch lengths, and each of the protruding teeth is from the front section The periphery projects outwardly and is positioned between adjacent two threads, each of the teeth extending along the longitudinal axis of the shaft for at least one pitch length. A screw having a cutting lug according to claim 1, wherein the front section includes an upper portion adjacent to the intermediate section and a lower portion spaced apart from the upper axis by the longitudinal axis, the lower portion extending at least along a longitudinal axis of the shaft The length of a pitch, the plurality of teeth are disposed at a lower portion of the front portion, and the upper portion is between the lower portion and the intermediate portion and no protrusion is disposed around the upper portion. According to the second aspect of the patent application, the screw having the cutting teeth, wherein the lower portion of the front section is provided with three spaced apart teeth, the tips of the respective teeth are pointed and the convex teeth protrude outwardly to a height smaller than the snail. The teeth are high. A screw having a cutting lug according to claim 3, wherein the front section has three arc angles spaced apart, and the three arc angles are arranged or overlapped with the three teeth. A screw having a cutting tooth according to claim 4, wherein a lower portion of the front portion extends a drill tail end, the drill end has a triangular cross section, and the drill end has three sharp corners, the three The sharp corners are aligned with the three arcuate corners of the front section on the longitudinal axis. A screw having a cutting tooth according to claim 4, wherein a lower portion of the front portion extends a drill tail end, the drill end has a triangular cross section, and the drill end has three sharp corners, the three The sharp corners and the three arc angles of the front section are staggered on the longitudinal axis. The screw having a cutting tooth according to claim 3, wherein a rod diameter of the middle portion is larger than a rod diameter of the front portion, and a top end of the plurality of convex teeth defines a convex outer diameter, the convex outer diameter being larger than the rod diameter The diameter of the middle section. The screw having a cutting tooth according to claim 7, wherein the rear section has a circular cross section, and the outer diameter of the rear section is larger than an outer diameter of the intermediate section, the thread extending from the tail end of the drill to the Middle section. A screw having a cutting tooth according to the eighth aspect of the patent application, wherein the rear section is provided with a plurality of spaced apart ribs, and the angle of each of the ribs to the longitudinal axis is between 10 and 30 degrees.