TW201918642A - Self-tapping screw head structure capable of effectively discharging chips and dispersing a pressure between an object and the screw - Google Patents

Abstract

A self-tapping screw head structure comprises a screw head, a rod body, a cone, and a thread. A direction along which the thread surrounds the cone and the rod body determines a tapping direction. The screw head includes a top portion; a first neck portion connected to the top portion and provided with a circumferential diameter gradually decreased toward a direction away from the top portion; a plurality of recessed portions recessed from a surface of the first neck portion; and a second neck portion connected to the first neck portion and provided with a circumferential diameter gradually decreased toward a direction away from the first neck portion. Each of the recessed portions includes a cutting blade end; a chips guide end away from the cutting blade end; a first accommodation slot disposed between the cutting blade end and the chips guide end; and a second accommodation slot disposed between the cutting blade end and the chips guide end, and adjacent to the first accommodation slot and away from the top portion, wherein a recess depth of the first accommodation slot is deeper than that of the second accommodation slot.

Description

Self-tapping screw head structure

The invention relates to a self-tapping screw head structure, in particular to a self-tapping screw head structure capable of preventing a split material after locking.

The width of the self-tapping screw head is usually wider than that of the screw, and forms a funnel-like shape to facilitate the locking of the screw after the screw is locked into the object, thereby achieving a better bonding effect. However, for wood with higher hardness, due to the high density and strong resistance, the screw is more difficult to screw in, and the wood chips generated during the screwing process are not effectively discharged, so that the wood chips remain in the wood. Wood chips are pressed by the pressure of the screw, which is liable to cause cracking of the wood.

Referring to the Taiwan Patent Publication No. I496997, a screw for accommodating wood chips is provided, which is mainly provided with a plurality of auxiliary blocks protruding outwardly from the bottom surface of the screw head, and an accommodating area is formed between the two adjacent auxiliary blocks. Each of the auxiliary blocks has a side wall on one side of the accommodating area and extends upwardly from the bottom surface to form a wall surface, and a wall surface is formed to be connected to the other side of the adjacent accommodating area. a wall and a cutting edge formed by contacting the wall with the top wall. Therefore, the auxiliary cutting by the auxiliary blocks enables the fastener to be quickly cut when it is locked into the lock compound, and the accommodating area can also be supplemented by the cutting chip after the cutting, thereby The lock compound produces a tight fit.

However, the screw is not ideal because of the chip removal speed, and the resistance is too high, so that the screw head is not easy to rotate. In actual use, the edge of the object is easily expanded and the screw hole is cracked. Therefore, how to improve the lack of prior technology is indeed an issue that the industry wants to overcome.

The object of the present invention is to solve the problem that the conventional screw cannot provide effective chip evacuation to disperse the pressure between the object and the screw.

In order to achieve the above object, the present invention provides a self-tapping screw head structure, comprising a screw head, a rod body connecting the screw head, a cone connecting the rod body away from one end of the screw head, and a cone from the cone a thread extending to the rod body, the thread surrounding the cone and the direction of the rod body determines a direction of penetration around the screw head forming a circumferential path, wherein the screw head includes a top portion, and the top portion is coupled to the top portion a first neck portion whose circumference is gradually decreased away from the top direction, a plurality of recesses recessed from the first neck surface and having a recessed depth along the tapping direction, and a first neck connected thereto and a circumferential path thereof a second neck portion that is gradually away from the first neck direction, wherein each of the recess portions respectively includes a chip end located at a shallowest depth of the recess, a cutting edge end away from the chip guide end and having the shallowest recess depth; a first pocket located between the cutting edge end and the chip guide end and adjacent to the top portion, and a first portion between the cutting edge end and the chip guide end and adjacent to the first pocket and away from the top Two pockets, the recess depth of the first pocket is relatively The second receiving groove deeper.

Further, a bottom surface of the first pocket forms a first plane, and a bottom of the second pocket forms a second plane, and the first plane and the second plane have an obtuse angle.

Further, each of the recesses respectively includes a third pocket between the cutting edge end and the chip guide end and adjacent to the second pocket and away from the first pocket, and the second pocket The depth of the depression is deeper than the third pocket.

Further, the bottom of the third pocket forms a third plane, and the third plane has an obtuse angle with the second plane.

Further, the decreasing rate of the first neck circumference is greater than the decreasing rate of the second neck circumference.

Further, the first neck has a longer length than the second neck.

Further, the cutting edge end and the chip guiding end are offset from the portion of the first receiving groove toward the tapping direction.

Therefore, the present invention has the following beneficial effects over the prior art:

1. In the process of the invention, the second neck with a small circumference will contact the object first, and then the first neck with a larger circumference will continue to avoid the resistance caused by the working process and reduce the cracking. The probability of damage, and the recessed area can accommodate and discharge wood chips, which can avoid hindering the tapping, and the wood chips will be accommodated in the receiving groove at the end of the tapping process, thereby increasing the bonding force with the object to achieve stable solidification effect. .

For a more detailed description of the technical features and operation modes of the present application, and with reference to the illustrations, please refer to the review. In addition, the drawings in this creation are not necessarily drawn to scale in order to facilitate the description, and the proportions in the drawings are not intended to limit the scope of the claimed invention.

Regarding the technique of the present invention, please refer to Figs. 1-1 to 1-4. The invention provides a self-tapping screw head structure 100 for tapping and locking an object 200 such as wood or plastic that does not require a predetermined drilling. The self-tapping screw head structure 100 includes a screw head 10, a rod body 20 connecting the screw head 10, a cone 30 connecting the rod body 20 away from the end of the screw head 10, and an extension from the cone 30. To the thread 40 of the rod 20, the direction of the thread 40 around the cone 30 and the rod 20 determines a direction of penetration 50 that forms a circumferential path around the head 10. The technical term "scraping direction 50" of the present invention can be specifically referred to in Figure 3-1. One of the operating slots 15 of the screw head 10 can be connected by a tool such as a screwdriver (not shown), and from the right side of the figure to the left side. Rotating, the screw as a whole is drilled and moved toward the object 200 on the lower side of the figure, wherein the direction in which the screw head 10 is rotated (from the right side to the left side of the drawing) is the tapping direction 50 of the present invention.

More specifically, referring to Figures 2-1 to 2-2, the screw head 10 includes a top portion 11, a first neck connected to the top portion 11 and having a circumferential diameter that decreases toward the front portion 11 12, a plurality of recesses 13 recessed from the surface of the first neck portion 12 and having a recessed depth along the tapping direction 50, and a connecting portion of the first neck portion 12 and a circumferential diameter thereof decreasing toward the first neck portion 12 The second neck 14 is. Further, the decreasing rate of the circumference of the first neck portion 12 is greater than the decreasing rate of the circumference of the second neck portion 14, and the length of the first neck portion 12 is longer than the length of the second neck portion 14. Therefore, during the tapping process, the second neck portion 14 having a smaller circumference will contact and tighten the object 200 first, and then the first neck portion 12 having a larger circumference will be connected to avoid excessive work. Resistance to reduce the chance of drilling cracks.

Each of the recesses 13 respectively includes a chip end 131 at a shallowest depth of the recess, a cutting edge end 132 away from the chip end 131 and having the shallowest depth, and a cutting edge end 132 and the guiding chip a first pocket 133 between the ends 131 and adjacent to the top portion 11, and a second pocket between the cutting edge end 132 and the chip guide end 131 and adjacent to the first pocket 133 and away from the top portion 11 134, the recessed depth of the first pocket 133 is deeper than that of the second pocket 134. In the embodiment, the bottom of the first pocket 133 forms a first plane 1331, and the bottom of the second pocket 134 forms a first The second plane 1341, and the first plane 1331 and the second plane 1341 have an obtuse angle. Therefore, referring to Figures 3-1 to 3-3, during the tapping process, the cutting edge end 132 will shave the wood fibers of the edge of the drill and produce wood chips (or plastic chips, depending on the object 200) After the wood chips enter the second volume 134 having a small volume, the reaction force due to the screwing will be along the first plane 1331 and the second plane 1341 toward the first volume having a larger volume. 133 move, in order to achieve the effect of chip removal and avoid cracking.

In addition, each of the recesses 13 includes a third receptacle 135 between the cutting edge 132 and the chip guide end 131 and adjacent to the second pocket 134 and away from the first pocket 133. The recessed depth of the second recess 134 is deeper than that of the third recess 135. The bottom of the third recess 135 forms a third plane 1351, and the third plane 1351 and the second plane 1341 have an obtuse angle. The third receiving groove 135 is used as a buffer before the wood chips enter the second receiving groove 134, and is placed at a lower end of the screw head 10 at a steep angle after the completion of the tapping, thereby reducing the pair of objects after the tapping. The screw 10 causes a reaction force.

The cutting edge end 132 and the chip guiding end 131 are offset from the portion of the first receiving groove 133 toward the tapping direction 50. In this embodiment, the cutting edge end 132 has a slight offset. Therefore, during the tapping process, the drilling is not subjected to the pulsed high pressure and causes cracking and the like, and the offset of the leading end 131 is more significant, and the purpose is to enable the wood chips to travel a long distance and make the wood chips It is evenly dispersed without causing wood chips to accumulate in the portion of the depressed portion 13.

In summary, the present invention provides a plurality of groove structures of different inclination degrees on the screw head 10, so that the waste materials generated during the tapping process can be accommodated in the plurality of pockets, and the reinforcement effect is generated when the tapping is completed. . In addition, a chip evacuation passage may be provided during the tapping process to disperse the compressive stress between the article 200 and the screw.

The content of the present invention has been described in detail above, but the above is only the preferred embodiment of the present invention, and the scope of the present invention cannot be limited by this, that is, the equal change of the scope of patent application according to the present invention is Modifications shall remain within the scope of the patents of this creation.

100‧‧‧ Self-tapping screw head structure

10‧‧‧ screw head

20‧‧‧ rod body

30‧‧‧ cone

40‧‧‧ thread

50‧‧‧In the direction of the attack

11‧‧‧ top

12‧‧‧First neck

13‧‧‧Depression

131‧‧‧guide ends

132‧‧‧ cutting edge

133‧‧‧first capacity

1331‧‧‧ first plane

134‧‧‧Second capacity

1341‧‧‧ second plane

135‧‧‧ third cavity

1351‧‧‧ third plane

14‧‧‧ Second neck

15‧‧‧Operation slot

200‧‧‧ objects

Figure 1-1 is a plan view showing a first embodiment of the present invention. Figure 1-2: is a cross-sectional view of the 1-1 figure at the A-A position. Figure 1-3: is a cross-sectional view of the 1-2 figure at the B-B position. Figure 1-4: is a cross-sectional view of the 1-2 position at the C-C position. Figure 2-1 is a perspective view of the screw head portion of the present invention. Fig. 2-2 is a partial enlarged view of the screw head portion of the present invention. Figures 3-1 to 3-3 are schematic views showing the continuous operation of the first embodiment of the present invention.

Claims (7)

A self-tapping screw head structure comprising a screw head, a rod body connecting the screw head, a cone connecting the rod body away from one end of the screw head, and a thread extending from the cone to the rod body, The thread surrounds the cone and the direction of the rod to determine a direction of penetration around the thread forming a circumferential path, wherein: the screw head includes a top portion, a top portion connected to the top portion and a circumferential direction away from the top direction a gradually decreasing first neck portion, a plurality of recesses recessed from the first neck surface and having a recessed depth gradually decreasing along the tapping direction, and a connecting to the first neck portion and a circumferential diameter thereof decreasing toward the first neck portion a second neck portion, wherein each of the recessed portions respectively includes a chip end located at a shallowest depth of the recess, a cutting edge end away from the chip guiding end and having the shallowest depth of the recess, one at the cutting edge end and the a first pocket between the chip ends and adjacent to the top, and a second pocket between the cutting edge end and the chip end and adjacent to the first pocket and away from the top, the first volume The recessed depth of the groove is deeper than the second recess. The self-tapping screw head structure according to the first aspect of the invention, wherein a first plane is formed at a bottom of the first pocket, a second plane is formed at a bottom of the second pocket, and the first plane and the first plane The two plane clips have an obtuse angle. The self-tapping screw head structure of claim 2, wherein each of the recesses respectively includes a gap between the cutting edge end and the chip guide end and adjacent to the second pocket and away from the first a third cavity of the cavity, and the second cavity has a recess depth deeper than the third cavity. The self-tapping screw head structure according to claim 3, wherein the third groove forms a third plane, and the third plane has an obtuse angle with the second plane. The self-tapping screw head structure according to claim 1, wherein a decreasing rate of the first neck circumference is greater than a decreasing rate of the second neck circumference. The self-tapping screw head structure of claim 1, wherein the first neck portion has a longer length than the second neck portion. The self-tapping screw head structure according to claim 1, wherein the cutting edge end and the chip guiding end are offset from the tapping direction by a portion corresponding to the first receiving groove.