TWI683711B - Cone hole drill - Google Patents

Abstract

This case is a tapered hole drill for drilling screw countersunk holes on an object. The tapered hole drill includes a front drill bit, a tapered portion, a rear drill bit, and a polygonal rod body located at the rear end of the rear drill bit. The outer diameter is smaller than the outer diameter of the rear drill bit, and the connection between the end of the front drill bit and the rear drill bit is a tapered portion with a set inclination angle. The front drill bit has more than two spiral cutting edges and more than two spiral chip removal grooves. The spiral cutting edge and spiral chip removal groove directly extend to the tapered part and the rear drill bit at the same spiral angle, so that the front bit, the tapered part and the rear drill bit have the same spiral angle and spiral chip removal groove that continue with each other ; The tapered part between the two spiral chip flutes next to each other forms a chamfered surface. The left side of the chamfered surface is shorter than the right side, so that the right chamfered area of the chamfered surface extends into the rear bit Within the range of the front end of the screw bit, and the front end of the spiral bit of the rear bit, which is connected to the end of the spiral chip ditch of the tapered part, is larger than the distance between the end of the spiral bit of the rear bit; The drill bit and the tapered part and the rear drill bit, as well as the spiral blade and spiral chip removal groove that continue with each other and have the same spiral angle, can indeed achieve the practical benefits of smooth chip removal, light drilling and fast saving.

Description

Cone hole drill

A tapered hole drill bit for drilling a countersunk screw hole on an object.

Generally, to complete the traditional processing steps of the countersunk head screw hole, it is necessary to use a small-diameter drill bit to drill a through hole in the processed object first, and then remove the drill bit and replace it with a predetermined larger-diameter milling cutter At the center of the originally drilled through hole, the milling cutter is used to complete the production of the countersunk head screw. This requires two steps and two drill changes to complete the countersunk head processing. This kind of processing has the following disadvantages in use:

(1) The conventional processing method needs to be processed twice, so the processing quality is more unstable due to human factors.

(2) The conventional processing method needs to be processed twice, so it is more time-consuming and labor-intensive, and the processing yield is slower.

Based on this, the related industry has improved a combined drill bit in which two drill bits with different outer diameters are connected in series and fixed to each other on the same axis, in order to simplify the step of drilling a countersunk screw hole on an object. Combined drills for countersunk head screws, as known bulletin No. M472573 "Drill structure device capable of forming countersunk head holes at one time", are assembled at the back of the drill bit with smaller outer diameter at the front end, and are combined by the fixing method of positioning bolt Large outer diameter drill bit on the same axis. However, this kind of drill bit connected in series has the following disadvantages in practical use:

(1) Combined with the fixing method of the positioning bolt, the overall drill bit has poor structural strength and limited service life.

(2) The cutting edges and chip removal groove of the two front and back drill bits do not continue with each other, resulting in unsmooth chip removal and high resistance to debris. In turn, it directly affects the drilling speed and productivity.

Therefore, how to create a drill with strong drill structure, long service life, accurate and rapid drilling, and fast production yield is the goal to be improved by technical creation.

The purpose of the creation of the "cone hole drill" in this case is to provide a drill with strong drill structure, long service life, accurate and rapid drilling, and fast processing and production efficiency.

The feature of this case is that it includes an integrally formed front drill bit at the front end, a tapered portion, a rear drill bit and a polygonal rod body located at the rear end of the rear drill bit, wherein the outer diameter of the front drill bit is smaller than the outer diameter of the rear drill bit, and the end of the front drill bit is set with a The tapered part of the inclination angle is connected to the rear drill bit. The front end of the tapered part has a minimum outer diameter that is the same as the outer diameter of the front end of the front bit, and the end of the tapered part is a maximum outer diameter that is the same as the outer diameter of the front end of the rear bit. ; The front drill bit has more than two spiral cutting edges and more than two spiral chip removal grooves. The spiral cutting edge of the front drill bit and the spiral chip removal groove continue directly to the tapered part and the rear drill bit at the same spiral angle, so that the front drill bit It has a helical cutting edge and a spiral chip groove with the same spiral angle as the tapered portion and the rear drill bit; the tapered portion between the two adjacent spiral chip grooves forms a chamfered surface, the left side of the chamfered surface The side length is shorter than the side length of the right side, so that the part of the chamfered area on the right side of the chamfered surface extends into the front end of the rear drill bit; the front end of the spiral bit of the rear bit connected to the end of the spiral chip groove of the tapered part is longer than the continuation The distance to the end of the spiral chip flute of the rear drill bit.

By forming the front drill bit, the tapered part and the rear drill bit integrally formed at the front end of the tapered hole drill bit, and the spiral blade and spiral chip removal groove that are continuous with each other and have the same spiral angle, the chip removal can be achieved Practical benefits of smooth, light drilling and fast saving.

1‧‧‧cone drill

11‧‧‧Front bit

12‧‧‧Cone

121‧‧‧Bevel

121A‧‧‧The length of the left side

121B‧‧‧The length of the right side

13‧‧‧Drill

14‧‧‧bar

2‧‧‧Screw blade

3‧‧‧Screw removal groove

3A‧‧‧Front pitch of the back chip spiral chip removal groove

3B‧‧‧End spacing of the back chip spiral chip ditch

Figure 1: The three-dimensional view of the best example of creation in this case (with three spiral blades and three spiral chip grooves).

Figure 2: Front view of Figure 1.

Figure 3: The right side view of Figure 2.

Figure 4: Another example of the creation of this case (with two spiral blades and two spiral chip grooves).

Figure 5: Right side view of Figure 4.

Please refer to the different embodiments of the creation of the "cone hole drill" shown in Figures 1 and 4 of the drawings, and the examples are only for the purpose of fully illustrating the preferred embodiment of the creation of this case. The scope of protection is not limited to this. All equivalent substitutions or transformations made by those skilled in the art based on the creation of this technology are within the protection scope of the creation of this case, and they are first declared.

Please refer to Figures 1 to 3 for the best embodiment of the tapered hole drill (with three spiral blades and three spiral chip removal grooves), including: a front bit 11 integrally formed at the front end of the tapered hole drill 1, The tapered portion 12, the rear drill bit 13, and the polygonal rod body 14 at the rear end of the rear drill bit 13. The outer diameter of the front drill bit 11 is smaller than the outer diameter of the rear drill bit 13, and the end of the front drill bit 11 is connected to the rear drill bit 13 with a tapered portion 12 having a set inclination angle. The front end of the tapered portion 12 is an outer diameter and a front The minimum outer diameter of the end of the drill bit 11 is the same, and the end of the tapered portion 12 is a maximum outer diameter that is the same as the outer diameter of the front end of the rear drill 13.

As shown in FIGS. 1 to 3, the front drill bit 11 has more than two spiral cutting edges 2 and more than two spiral chip flutes 3, and the spiral cutting edge 2 and the spiral chip fluting 3 of the front bit 11 are directly The same helical angle continues to the tapered portion 12 and the rear drill bit 13, so that the front bit 11 and the tapered portion 12 and the rear drill bit 13 have the helical cutting edge 2 and the helical chip removal groove 3 that are mutually continuous and have the same helical angle; The tapered portion 12 between the two spiral chip grooves 3 forms a chamfered surface 121 whose side length 121A on the left side is shorter than the side length 121B on the right side so that the chamfered surface 121 is partially chamfered on the right side It extends into the front end of the rear drill bit 13. However, the front end pitch 3A of the helical chip groove 3 of the rear drill bit 13 connected to the end of the helical chip groove 3 of the tapered portion 12 is greater than the end pitch 3B of the helical chip groove 3 continued to the rear bit 13.

As shown in FIGS. 4-5, another embodiment of the present tapered hole drill bit (with two spiral cutting edges and two spiral chip removal grooves) includes: a front drill bit 11 integrally formed at the front end of the tapered hole drill bit 1, The tapered portion 12, the rear drill bit 13, and the polygonal rod body 14 at the rear end of the rear drill bit 13. The outer diameter of the front drill bit 11 is smaller than the outer diameter of the rear drill bit 13, and the end of the front drill bit 11 is connected to the rear drill bit 13 with a tapered portion 12 having a set inclination angle. The front end of the tapered portion 12 is an outer diameter and a front The minimum outer diameter of the end of the drill bit 11 is the same, and the end of the tapered portion 12 is a maximum outer diameter that is the same as the outer diameter of the front end of the rear drill 13.

As shown in FIGS. 4 to 5, the front drill bit 11 has two spiral cutting edges 2 and two spiral chip flutes 3, and the spiral cutting edge 2 and the spiral chip fluting 3 of the front bit 11 continue directly at the same spiral angle To the tapered portion 12 and the rear drill bit 13, the front drill bit 11 and the tapered portion 12 and the rear drill bit 13 have a spiral blade 2 and a spiral chip groove 3 that are continuous with each other and have the same spiral angle; The tapered portion 12 between the chip grooves 3 forms a chamfered surface 121 whose side length 121A on the left side is shorter than the side length 121B on the right side so that a part of the chamfered surface 121 on the right side extends into the rear bit 13 Within the front end. However, the front end pitch 3A of the helical chip groove 3 of the rear drill bit 13 connected to the end of the helical chip groove 3 of the tapered portion 12 is greater than the end pitch 3B of the helical chip groove 3 continued to the rear bit 13.

With this case, the front bit, the tapered part and the rear bit, which are integrally formed on the front end of the tapered hole bit, as well as the spiral blade and spiral chip removal groove that are continuous and have the same spiral angle, can achieve smooth chip removal, light drilling and fast and practical benefit.

1‧‧‧cone drill

11‧‧‧Front bit

12‧‧‧Cone

121‧‧‧Bevel

121A‧‧‧The length of the left side

121B‧‧‧The length of the right side

13‧‧‧Drill

14‧‧‧bar

2‧‧‧Screw blade

3‧‧‧Screw removal groove

3A‧‧‧Front pitch of the back chip spiral chip removal groove

3B‧‧‧End spacing of the back chip spiral chip ditch

Claims (2)

A tapered hole drill is characterized by comprising a front drill bit, a tapered part, a rear drill bit and a polygonal rod body located at the rear end of the rear drill head, the outer diameter of the front drill bit is smaller than the outer diameter of the rear drill bit, and the end of the front drill bit is A tapered part with a set inclination angle is connected to the rear drill bit; the front drill bit has more than two spiral cutting edges and more than two spiral chip removal grooves, the spiral cutting edge of the front drill bit and the spiral chip removal groove are directly at the same spiral angle Continue to the tapered part and the rear drill bit, so that the front bit, the tapered part and the rear drill bit have a spiral blade and a spiral chip groove that are mutually continuous and have the same spiral angle; the cone between the two adjacent spiral chip grooves The shape part forms a chamfered surface, the left side of the chamfered side is shorter than the right side, so that the chamfered area of the right side of the chamfered surface extends into the front end of the rear drill; The distance between the front end of the spiral chip flute of the rear drill bit at the end is greater than the distance between the ends of the spiral chip flute which continues to the rear bit. According to the taper hole bit in item 1 of the patent application scope, the front end of the tapered portion connected between the front end of the front bit and the front end of the rear bit is a minimum outer diameter equal to the outer diameter of the front end of the front bit. The end is a maximum outer diameter with the same outer diameter as the outer diameter of the front end of the rear bit.

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