JP2700074B2 - Drill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drill used for metal working, crushing of a tap broken in a screw hole, drilling of concrete, and the like.

[0002]

2. Description of the Related Art FIGS. 16 and 17 show a drill 1 according to a conventional example. The drill 1 is made of a powdered high-speed sintered material. Reference numeral 2 denotes a quadrangular prism-shaped main body, and a quadrangular pyramid-shaped blade portion 3 is integrally formed at a lower end portion of the main body 2. The blade portion 3 moves the main body 2 from the ridge 2a to the axis (rotation axis).
It is formed by removing in a plane toward L.

[0003]

However, in the above-mentioned conventional drill 1, the vertex 3a of the blade 3 is located at the axis L of the main body 2.
Since it is located on the upper side, the vertex 3a hardly rotates, and does not perform the cutting function. Therefore, as shown in FIG.
When the blade 3 is to be crushed, the vertex 3a of the blade 3
And the tap 5 cannot be efficiently cut.

If the pressing force of the drill 1 is increased in order to increase the cutting performance of the drill 1, the apex 3a may slide in the lateral direction, causing the drill 1 to break or damaging the female screw of the screw hole 4. There is. The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide a drill having a high cutting ability.

[0005]

According to a first aspect of the present invention, there is provided a holding portion, a prism-shaped main body formed in the holding portion, and a cross section gradually reduced toward an end formed at an end of the main body. In a drill having a blade portion, the blade portion has a plurality of ridges, and a pyramid portion provided at a position where the plurality of ridges are continuous with the ridge of the main body; And a cut surface that crosses the rotation axis at a predetermined angle with respect to the orthogonal line.

A second aspect of the present invention is the drill according to the first aspect, wherein a groove is formed in the cut surface.

According to a third aspect of the present invention, there is provided the drill according to the second aspect, wherein a communication groove which communicates with the groove and extends so as to be continuous with the main body is formed.

[0008] The invention of claim 4 is the invention of claim 1, 2, or 3.
The drill according to any one of claims 1 to 3, wherein a discharge groove continuous with the main body and the pyramid portion is formed.

According to a fifth aspect of the present invention, there is provided the drill according to any one of the first to third aspects, wherein a hole communicating with the pyramid portion and the end surface of the holding portion is formed.

The invention according to claim 6 is the invention according to claims 1, 2, 3, and 4.
Or The drill according to 5, wherein at least a part of the holding portion is formed to have a smaller diameter than the main body.

[0011]

According to the first aspect of the present invention, since the apex of the drill is deviated with respect to the rotation axis, the apex turns when the drill rotates, so that the cutting can be performed efficiently.

According to the second aspect of the present invention, since the grooves are formed, the contact area with the workpiece is reduced, and the chips are discharged through the grooves.

According to the third aspect of the present invention, the cutting chips are discharged from the groove through the communication groove.

According to the fourth aspect of the invention, the cutting chips are discharged through the discharge grooves.

According to the fifth aspect of the present invention, the chips can be sucked out from the holes, and air can be sent from the holes to blow the chips.

According to the sixth aspect of the present invention, the cutting chips are discharged through a portion having a smaller diameter than the main body of the holding portion.

[0017]

An embodiment of the present invention will be described with reference to the drawings. 1 to 3 show a drill 1 according to a first embodiment.
1 will be described. The drill 11 is made of a cemented carbide or powdered high-speed sintered material. In addition, the drill 11 can also be manufactured by using a blade or a tip. Reference numeral 13 denotes a columnar holding portion.
Is integrally formed with a hexagonal prism-shaped main body 15. A blade portion 17 is integrally provided at a distal end portion of the main body 15, and the blade portion 17 is formed in a shape whose cross section gradually decreases toward the distal end side (left side in the drawing). The blade portion 17 includes a hexagonal pyramid-shaped pyramid portion 19 and a cut section 2 obtained by cutting the top of the pyramid portion 19.
1 and a V-shaped groove 27 extending longitudinally through the cut surface 21.

The pyramid portion 19 is provided with a plurality of ridges 31,
The ridge 31 is provided at a position continuous with the plurality of ridges 35 of the corresponding main body 15. The pyramid surface 29 of the pyramid portion 19 is formed in an arc shape having a radius equal to a half of the diameter of the main body 15, and the ridge 31 is formed with a predetermined curvature. The cut surface 21 is constituted by a surface 23 on the outer peripheral side and a surface 25 on the axial center side, and is formed in the pyramid portion 19. The cut surface 21 is formed from the main body 15 side to the front end (left side in the drawing). The inclination angle α1 of the outer peripheral surface 23 is set to about 45 degrees, the inclination angle α2 of the axial surface 25 is set to approximately 15 degrees, and the axial surface 25 crosses the rotation axis L. In FIG. 1, it is formed to a region below the rotation axis L. Therefore, the vertex 37 is offset with respect to the rotation axis L of the main body 15.

As shown in FIG. 2 and FIG.
7, the cutting surface 21 is longitudinally cut in the longitudinal direction. The groove 27 has a length dimension reaching the corner A which is the base end of the pyramid portion 19, and the angle θ of the groove 27 is set to about 90 degrees.

In the drill 11, the apex 37 is deviated from the rotation axis L, so that when the drill 11 rotates, the apex 3
7 turns around the rotation axis L. Therefore, the object to be cut can be efficiently cut. Groove 2
Since 7 is formed, the contact area of the cut surface 21 with the object to be cut becomes small, and the cutting resistance is reduced. Cutting chips are discharged through the groove 27.

A drill 41 according to a second embodiment will be described with reference to FIGS. Reference numeral 45 denotes a hexagonal column-shaped main body, and a blade portion 47 is integrally provided at a front end portion of the main body 45, and the blade portion 47 is formed in a shape whose cross section gradually decreases toward the front end side (left side in the drawing). ing. Blade 4
7 is a hexagonal pyramid-shaped pyramid portion 49, a cut section 51 obtained by cutting the top of the pyramid section 49, and a V that cuts the cut section 51 longitudinally.
And a groove 57 in the shape of a circle.

The pyramid surface 59 and the ridge 61 of the pyramid portion 49 are
It corresponds to the main surface 63 and the ridge 65 of the main body 45. Further, the twill 61 is inclined with respect to the orthogonal line of the main body 45 with a straight line. The cut surface 51 is constituted by a surface 53 on the outer peripheral side and a surface 55 on the axial center side, and the surface 55 is formed by being cut deeper than the rotation axis L. The inclination angle α3 of the outer peripheral surface 53 is set to approximately 35 degrees, the inclination angle α4 of the axial center surface 55 is set to approximately 15 degrees, and the vertex 37 is biased with respect to the rotation axis L of the main body 45. I have.

As shown in FIG. 2 and FIG.
The cut surface 51 is longitudinally cut from the vertex 67 of 7 in the longitudinal direction. The groove 57 has a length dimension reaching the corner A which is the base end of the pyramid 49, and the angle θ of the groove 57 is set to about 90 degrees. This drill 41 also exhibits the same operation and effect as the drill 11 according to the first embodiment.

The drill according to the embodiment described below has the same components as the drill 11 according to the first embodiment.
Portions having the same configuration are denoted by the same reference numerals as in the first embodiment, and description thereof is omitted. A drill 71 according to a third embodiment will be described with reference to FIGS. The configuration of the drill 71 is the same as that of the drill 11 according to the first embodiment except that a communication groove 73 is provided. The communication groove 73 is
The holding portion 13 communicates with the groove 27, extends along the main body 15, and is formed up to a boundary position between the holding portion 13 and the main body 15. The drill 71 discharges cutting chips through the groove 27 and the communication groove 73. Therefore, the cutting waste can be discharged more efficiently.

A drill 81 according to a fourth embodiment will be described with reference to FIGS. The drill 81 according to the first embodiment is the same as the drill 1 except that four drill grooves 83 are provided.
1 and its configuration are the same. The discharge groove 83 communicates with the groove 27. In the drill 81, the cutting chips are formed in the groove 27 and the discharge groove 8
It is discharged through 3. Further, the discharge groove 83 may not be connected to the groove 27.

A drill 91 according to a fifth embodiment will be described with reference to FIG. The drill 91 has the same configuration as the drill 11 according to the first embodiment except that the pyramid surface 94 of the pyramid portion 93 and the main surface 96 of the main body 95 are formed to be curved toward the rotation axis L. I do. In this drill 91, the rake angle of the blade portion 97 is smaller than in the drill of the above embodiment, and the cutting ability is improved. Further, since the contact area with the workpiece is reduced, the cutting resistance of the blade portion 97 is further reduced.

A drill 101 according to a sixth embodiment will be described with reference to FIG. Drill 101 is pyramid 103
And except that the main body 105 is formed in a twisted shape,
The configuration is the same as that of the drill 11 according to the first embodiment. In this drill 101, the pyramid portion 103 and the main body 1
Since 05 is formed in a twisted shape, the cutting resistance is further reduced.

A drill 111 according to a seventh embodiment will be described with reference to FIGS. Drill 111 is hole 1
The drill 1 according to the first embodiment, except that the drill 16 is formed.
1 and its configuration are the same. The opening of the hole 116 is the pyramid 1
9 are formed on the pyramidal surface 29 of the ninth and the end surface of the holding portion 13 and
Reference numeral 16 communicates with the pyramid surface 29 and the end surface of the holding portion 13.

In this drill 111, a suction device is connected to the opening of the hole 116 formed on the end face of the holding portion 13,
The cutting chips are sucked and removed from the holes 116. Alternatively, an air injection device is connected to the opening of the hole 116 formed on the end surface of the holding portion 13, and air is sent from the hole 116 to blow off and remove cutting chips.

A drill 121 according to an eighth embodiment will be described with reference to FIG. Drill 121 is holding part 123
The configuration is the same as that of the drill 11 according to the first embodiment except that the diameter of the drill 11 is smaller than that of the main body 15. In the drill 121, since the diameter of the holding portion 123 is formed smaller than the diameter of the main body 15, cutting chips are removed from the holding portion 123.
Is discharged around the area. It is possible to improve the dischargeability of cutting chips. Note that only a part of the holding unit 123 is
5 may be smaller than the diameter.

Although the embodiment of the present invention has been described in detail above, the specific configuration is not limited to this embodiment, and even if there is a change in the design without departing from the gist of the present invention, the present invention is not limited to this embodiment. Included in the invention. For example, drills 71, 81, 91, 10 according to the fourth to eighth embodiments.
Drills 71 according to the third embodiment are provided at 1, 111 and 121.
The groove 27 may be formed as shown in FIG.

In the drills 11, 41, 71, 81, 91, 101 and 111 according to the first to seventh embodiments, similarly to the drill 121 according to the eighth embodiment, the holding portion has a smaller diameter than the main body. May be formed. In the above embodiment, the pyramid portion and the main portion are hexagonal, but the present invention is not limited to this, and may be triangular, square, pentagonal, or heptagon or more. In the above embodiment, the grooves 27 and 57 are V
Although formed in a shape, the present invention is not limited to this, and may be another shape such as a U shape. The number of the discharge grooves 83 according to the fourth embodiment is not limited to four, and may be less or more than four.

[0033]

As described above, according to the present invention, the cutting ability of the drill is dramatically improved. Further, cutting resistance can be reduced. Cutting chips can be efficiently discharged.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a drill according to a first embodiment of the present invention.

FIG. 2 is a front view of the drill according to the first embodiment of the present invention.

FIG. 3 is a sectional view taken along line DD of FIG. 2;

FIG. 4 is a side view of a main part of a drill according to a second embodiment of the present invention.

FIG. 5 is a front view of a drill according to a second embodiment of the present invention.

FIG. 6 is a sectional view taken along line DD of FIG. 5;

FIG. 7 is a side view of a main part of a drill according to a third embodiment of the present invention.

FIG. 8 is a front view of a drill according to a third embodiment of the present invention.

FIG. 9 is a side view of a main part of a drill according to a fourth embodiment of the present invention.

FIG. 10 is a front view of a drill according to a fourth embodiment of the present invention.

FIG. 11 is a front view of a drill according to a fifth embodiment of the present invention.

FIG. 12 is a side view of a main part of a drill according to a sixth embodiment of the present invention.

FIG. 13 is a side view of a main part of a drill according to a seventh embodiment of the present invention.

FIG. 14 is a front view of a drill according to a seventh embodiment of the present invention.

FIG. 15 is a side view of a drill according to an eighth embodiment of the present invention.

FIG. 16 is a side view of a drill according to a conventional example.

FIG. 17 is a front view of a drill according to a conventional example.

[Explanation of symbols]

 11, 41, 71, 81 Drill 91, 101, 111, 121 Drill 13, 123 Holding part 15, 45, 95, 105 Main body 17, 47, 97 Blade part 19, 49, 93, 103 Pyramid part 21, 51 Trimming section 23, 25, 53, 55 surface 27, 57 groove 29, 59, 94, 96 pyramid surface 31, 61 pyramid ridge 33, 63 main surface 35, 65 main ridge 37, 67 vertex 73 communication groove 83 discharge groove 116 Hole A Corner L Rotation axis

Claims (6)

(57) [Claims] 1. A drill comprising: a holding portion; a prismatic main body formed in the holding portion; and a blade portion formed at an end of the main body and having a cross section that gradually decreases toward a tip. Having a plurality of ridges, a pyramid portion provided at a position where the plurality of ridges are continuous with the ridge of the main body, formed at the pyramid portion, at a predetermined angle with respect to an orthogonal line of the main body, A drill characterized by comprising a cutting surface crossing a rotation axis. 2. The drill according to claim 1, wherein a groove is formed in the cut surface. 3. The drill according to claim 2, further comprising a communication groove communicating with the groove and extending extending from the main body. 4. The drill according to claim 1, wherein a discharge groove continuous with the main body and the pyramid portion is formed. 5. The drill according to claim 1, wherein a hole communicating with the pyramid portion and a terminal surface of the holding portion is formed. 6. The method of claim 1, 2, 3, 4, or 5,
A drill, wherein at least a part of the holding portion is formed to have a smaller diameter than the main body.