JP4233575B2 - Core cutter - Google Patents

Description

  The present invention relates to a core cutter, and more particularly to a core cutter that is most suitable for drilling work on a workpiece such as metal, resin material, polymer material, stone material, cement, and wood.

  The core cutter is used for various drilling (drilling) operations because of its good drilling efficiency and good drilling shape of the circular hole. For example, the core cutter is used when a through hole for piping of an air conditioner is drilled in a wall of a building or the like, or when a drain pipe is penetrated later into the soil (floor) where concrete is placed, or This is used when a through hole is formed in a metal member.

In such a core cutter, a blade part for cutting an object to be drilled is formed at the tip of a cylindrical body part. And, the core cutter is an electric drill through the attachment part formed at the base end of the core cutter itself or the attachment part formed at the base end of the attachment for attaching the core cutter. Attached to a rotary drive tool. And in order to improve cutting performance, the said blade body part may be comprised with a hard material compared with the material of a trunk | drum, for example, a cemented carbide alloy in recent years.
In the case of the core cutter having such a configuration, a concave portion is formed at an appropriate interval in the distal end portion of the trunk portion, and the blade body portion is fixed to the concave portion by means such as brazing, so that the blade body is attached to the distal end of the trunk portion. Plant the department.

The present inventor also provides a core cutter having such a configuration (see Patent Document 1).
International Publication Number WO2006 / 025230 A1.

  In the case of the core cutter having the above configuration, when trying to manufacture, specifically, using an automatic manufacturing apparatus, the blade body part is temporarily disposed in the concave part formed in the body part, and brazed, etc. If the blade body is to be fixed in the recess, the blade part is difficult to position accurately in three dimensions with respect to the body part, and it must be manufactured by using some kind of positioning aid. It was. In such a case, the configuration of the automatic manufacturing apparatus becomes complicated due to the arrangement of the auxiliary tools, or when the auxiliary tools are not used, the positioning of the blade body portion with respect to the body portion is poor.

  The present invention has been made in view of such a current situation, and when manufacturing a core cutter using an automatic manufacturing apparatus, it is possible to accurately and easily position the blade body part with respect to the body part. An object of the present invention is to provide a core cutter having a simple structure.

  A core cutter according to the present invention includes a plurality of recesses formed in the circumferential direction spaced apart from each other in order to plant a base portion of a blade body at a tip of a cylindrical body, and a blade body implanted in the recess. A core cutter provided with a discharge groove formed adjacent to the concave portion and in front of the concave portion in the rotational direction of the core cutter, wherein the front end portion of the concave portion in the rotational direction of the core cutter is the discharge groove. A first positioning wall surface extending in the circumferential direction so as to contact the inner peripheral surface of the blade body portion is formed in the discharge groove, and the blade body is formed at a base end portion of the recess. A second positioning wall surface with which the base end of the blade portion abuts is formed, and a third positioning wall surface with which the rotation direction rear end of the blade body portion abuts is formed at the rotation direction rear end portion of the recess. Features.

According to the core cutter configured as described above, when the blade body portion is positioned in the concave portion of the body portion, the inner peripheral surface of the blade body portion is brought into contact with the first positioning wall surface. The blade body portion can be positioned in the radial direction of the core cutter, and the blade body portion can be positioned in the axial direction of the core cutter by bringing the base end of the blade body portion into contact with the second positioning wall surface. In addition, the blade body portion can be positioned in the circumferential direction of the core cutter by bringing the rear end of the blade body portion in the rotation direction into contact with the third positioning wall surface. That is, it becomes possible to accurately position the blade body part three-dimensionally with respect to the body part. For this reason, even if it uses an automatic manufacturing apparatus, it becomes possible to position and manufacture a blade body part in the recessed part of a trunk | drum easily and correctly. Of course, even when the operator manually manufactures while visually observing, the blade body portion can be accurately positioned and positioned in the concave portion of the body portion.
In addition, since the front end in the rotation direction of the blade body portion faces the discharge groove and is disposed open, it is possible to smoothly discharge the chips cut by the blade body portion to the discharge groove side. It becomes.

In the core cutter, the first positioning wall surface is configured by an inclined surface that is inclined toward the inner diameter side on the distal end side when viewed from the front in the rotation direction, and is an inner peripheral surface of the blade body portion that contacts the first positioning wall surface. Is composed of an inclined surface corresponding to the inclined surface of the first positioning wall surface,
The contact between the second positioning wall surface and the base end of the blade body portion is contact in a direction in which movement of the blade body portion toward the base end in the axial direction of the core cutter is restricted.
The blade part is moved toward the base end side of the body part while the inclined surfaces are in contact with the body part until the base end of the blade part comes into contact with the second positioning wall surface ( It is possible to accurately position the blade body portion three-dimensionally with respect to the concave portion of the body portion simply by sliding the blade portion.

  Further, in the core cutter, the contact between the second positioning wall surface and the base end of the blade body portion is performed by a surface including a line perpendicular to the axial direction of the core cutter when viewed from the front in the rotation direction. If comprised, it will become a core cutter of the structure which is easy to perform exact positioning of this blade body part in the axial direction of a core cutter.

Further, in the core cutter, the abutment includes an inclined surface in which the second positioning wall surface is inclined toward the proximal end on the inner diameter side when viewed from the front in the rotation direction, and a proximal end surface of the blade body portion is the second end surface. When the contact with the inclined surface corresponding to the inclined surface of the positioning wall surface is combined with the configuration in which the corresponding portion of the first positioning wall surface and the blade body portion in contact with the inclined surface is configured with an inclined surface, the directions are different. With the positioning function by the two pairs of inclined surfaces, the blade body portion can be accurately positioned with respect to the body portion in the radial direction of the core cutter, and the position can be self-held. . Such a configuration is a particularly preferable configuration when manufacturing using an automatic manufacturing apparatus.

  Further, in the core cutter, the contact portion of the inner peripheral surface of the blade body portion that contacts the first positioning wall surface and the corresponding portion of the outer peripheral surface of the blade body portion corresponding to the corresponding contact portion are the same. When it is a direction inclined surface, it becomes the structure which can effectively discharge | emit the chip cut by the blade body part to the discharge groove.

  According to the core cutter according to the present invention, it is possible to provide a core cutter having a configuration capable of accurately and easily positioning the blade body portion on the body portion even when the automatic cutter is used for manufacturing. .

  Therefore, it becomes possible to mass-produce core cutters with high dimensional accuracy.

(Embodiment 1)
Hereinafter, an embodiment of a core cutter according to the present invention will be specifically described with reference to the drawings.

  FIG. 1 is an overall side view showing an overall schematic configuration of a core cutter according to an embodiment of the present invention, and FIG. 2 is a view of the core cutter shown in FIG. 1 from the front end side (in the direction of arrows II-II in FIG. 1). FIG. 3 shows the blade body shown in FIGS. 1 and 2 and the blade body showing the configuration of the recesses formed in the body part for implanting the blade body before the blade body is implanted. It is the elements on larger scale of a recessed part and a blade part.

  As shown in FIG. 1, a core cutter A according to the present embodiment is disposed at a distal end (lower end in FIG. 1) at an appropriate interval at a distal end (a lower end in FIG. 1) of a blade body 2 that cuts an object to be drilled. And a mounting portion (also referred to as a shank) disposed on the base end (upper end in FIG. 1) of the body portion 1 for mounting on the drive shaft side of a rotary power tool (for example, an electric tool such as an electric drill). 3). However, when the attachment portion 3 is configured to be attached via an attachment attachment (not shown) when attaching the core cutter A (body portion 1) to the rotary power tool, the attachment portion 3 It may be provided at the base end of the attachment. That is, the attachment part 3 has a selective configuration as the configuration of the core cutter A.

  By the way, in the case of this embodiment, the trunk portion 1 has a two-stage cylindrical shape with different diameters, and a connecting portion located in the middle connecting the cylindrical portions having different diameters, A flange portion 1 </ b> A that protrudes in a hook shape (ring shape) toward the outer diameter is formed.

  A plurality of recesses 1B (see FIG. 3) are formed at appropriate intervals at the front end of the body 1, and the blade bodies 2 are respectively implanted in these recesses 1B.

  Further, a discharge groove 4 is formed adjacent to the recess 1B in each front in the rotation direction R (rotation from right to left in FIG. 1; counterclockwise in FIG. 2) of the recess 1B. Yes. And most (front-end | tip part) of the front end 1b in the rotation direction of this recessed part 1B is open | released so that the said discharge groove | channel 4 may be faced. That is, the front end portion of the front end 1b of the recess 1B communicates with the discharge groove 4 to form one space. In this embodiment, a part of the tip 1b of the recess 1B (a portion 1c on the base end (upper end in FIG. 3) side of the front end of the recess 1B in FIG. 3) is partitioned by the edge of the discharge groove 4. .

Further, as shown in FIG. 3B, the distal end portion of the discharge groove 4 is configured by an inclined surface 4A whose lower end is inclined toward the inner diameter side of the core cutter A when viewed from the front or rear in the rotation direction R. The inclined surface 4 </ b> A and the vertical surface 4 </ b> B located above the inclined surface 4 </ b> A are extended by a predetermined dimension in the circumferential direction of the core cutter A. The inclined surface 4A constitutes the first positioning wall surface 10. Alternatively, in the case of this embodiment, it can be said that the first positioning wall surface 10 is constituted by the inclined surface 4A and the vertical surface 4B.
The inclined surface 4A (or the inclined surface 4A and the vertical surface 4B) which is the first positioning wall surface 10 is a part of the inner peripheral surface 2p of the blade body 2 illustrated in FIG. The blade body 2 is positioned in the inner peripheral direction.

In addition, the base end 2u of the blade body portion 2 abuts on the base end portion of each recess 1B described above, and restrains the movement of the blade body portion 2 in the base end direction with respect to the recess 1B. A second positioning wall surface 20 for performing positioning is formed. In the case of this embodiment, the second positioning wall surface 20 has an inverted U-shape when viewed from the side. Further, the surface forming the second positioning wall surface 20 includes a surface including a line orthogonal to the axial direction L of the core cutter A (see FIGS. 1, 3, and 4) when viewed from the front in the rotation direction R. In other words, the surface of the base end 2u of the blade body portion 2 is also formed in the axial direction L of the core cutter A while being configured by a surface in which a line orthogonal to the axial direction L of the core cutter A is continuously formed. It is composed of surfaces on which orthogonal lines are continuously formed.
However, instead of the configuration, the surface forming the second positioning wall surface 20 and the surface of the base end 2u of the blade body 2 are not shown, but the inclined surfaces 320, 302u in the opposite direction to the inclined surface 4A are not shown. (Refer to the thick two-dot chain line in FIG. 4B). In such a configuration, the blade body portion 2 is self-supported in the recess 1B by contact with two pairs of inclined surfaces in different directions. And it becomes possible to arrange temporarily in the state where it was positioned correctly.

  Further, the rear end 2r in the rotation direction of the blade body portion 2 abuts on the rear end portion in the rotation direction R of the recess 1B, and the blade body portion 2 is positioned rearward in the rotation direction R. A positioning wall surface 30 is formed. In the case of this embodiment, the third positioning wall surface 30 is constituted by a flat surface, and this flat surface is inclined in a direction in which the front end side is positioned in front of the rotational direction R as shown in FIG. is doing.

By the way, as illustrated in FIGS. 4, 7, and the like, the blade body portion 2 includes a base portion 2 </ b> B and a protruding portion 2 </ b> C disposed in front of the rotation direction R. Further, the base end of the base portion 2B of the blade body portion 2 has a form protruding to the base end side from the base end of the protruding portion 2C, and the protruding portion 2t is the second portion in a side view. It has an inverted U-shape corresponding to the positioning wall surface 20 and is configured to abut three-dimensionally (in a plurality of directions other than the radial direction) on the second positioning wall surface 20.
Further, as shown in FIG. 3, FIG. 4 or FIG. 7, an outer blade 2W and an inner blade 2Q are formed on the base portion 2B of the blade body portion 2, as shown in FIG. 7B. Furthermore, the front end 2h in the rotation direction R of the outer cutter 2W is located rearward in the rotation direction R with respect to the front end 2i in the rotation direction R of the inner cutter 2Q. Further, the distal end 2j of the outer cutter 2W has a form that is located slightly toward the proximal end (upward in FIG. 7B) with respect to the tip 2k of the inner cutter 2Q.
Further, the protruding portion 2C is formed so as to protrude forward from the inner blade 2Q in the rotational direction R, and the entire protruding portion 2C is viewed from the front in the rotational direction R as shown in FIG. As shown in (a), it has a parallelogram shape. In other words, the inner peripheral surface 2F of the projecting portion 2C is constituted by the inclined surface 2f having the same inclination angle as the inclined surface 4A of the discharge groove 4 and the vertical surface 2g adjacent to the lower surface, and the inner peripheral surface 2F. In this embodiment, the inclined surface 2 f constitutes the “part of the inner peripheral surface 2 p of the blade body portion 2” in contact with the first positioning wall surface 10. As shown in FIG. 4 (b), the vertical surface 2g of the inner peripheral surface 2F is located inside the discharge groove 4 in a state where the blade body portion 2 is attached to a predetermined position of the recess 1. It is configured to be flush with the peripheral surface 4F. Furthermore, the inclined surface 2d of the outer peripheral surface 2D of the protruding portion 2C is configured by an inclined surface parallel to the inclined surface 2f of the inner peripheral surface 2F. However, the inclined surface 2d is not necessarily a parallel inclined surface. For example, the inclined surface 2d may be an inclined surface having a larger inclination angle than the inclined surface 2f, or may have an opposite configuration. May be. Furthermore, the inclined surface 2d may be an inclined surface whose inclination angle changes in the middle of the axial direction L. However, as described above, when the inclined surface 2d is configured by an inclined surface parallel to the inclined surface 2f of the inner peripheral surface 2F, the configuration of the blade body portion 2 of the embodiment illustrated in FIGS. This is a preferred embodiment.
Further, the rear end 2r in the rotational direction R of the blade body 2 that contacts the third positioning wall surface 30, in this embodiment, the rear end surface 2E in the rotational direction R is shown in FIG. As illustrated in b), it is configured by a flat surface inclined at the front end in the rotational direction R.

In the state where the blade body portion 2 is implanted in the concave portion 1B of the body portion 1, the distal end of the blade body portion 1 is more distal than the distal end of the body portion 1, as shown in FIG. It will be in the state which protruded.
As shown in FIG. 2 or FIG. 4 (or FIG. 5 or FIG. 6), the outermost diameter end of the blade body portion 2 projects outward from the outermost diameter end of the body portion 1, and The innermost diameter end of the blade body portion 2 protrudes inward from the innermost diameter end of the body portion 1.

Therefore, the core cutter according to the present embodiment configured as described above has the following operational effects. That means
When the blade body portion 2 is implanted in the recess 1B formed in the body portion 1, the blade body portion 2 is brought into contact with the recess 1B while being brought close to the distal end (or outer diameter side). Then, the blade part 2 is positioned in three different directions by the first positioning wall surface 10, the second positioning wall surface 20, and the third positioning wall surface 30. As a result, the blade body 2 can be accurately and easily positioned with respect to the body 1 in three dimensions. In addition, such positioning simply requires the blade body portion 2 to be brought into contact with the concave portion 1B while approaching from the distal end side (or outer diameter side). Even an unskilled person can accurately perform positioning.

According to the core cutter A configured as described above, when the object to be drilled is drilled, as shown in FIG. 5, the chips generated at the tip of the blade body portion 2 are removed from the discharge groove. Led to 4. In particular, since the chips cut by the inner blade 2Q of the blade body part 2 are guided to the inclined surface 2d and discharged to the discharge groove 4, the conventional core cutter A1 shown in FIG. The gap between the inner peripheral surface of the inner blade 2Q and the drilled hole 40 (see FIG. 6) does not hinder smooth cutting.
(Embodiment 2)
By the way, the blade body portion is not limited to the one shown in FIGS. 1 to 4, but as shown in FIG. 8, an intermediate blade 102S is provided between the inner blade 102Q and the outer blade 102W. The blade body portion 102 may be provided. In such a configuration, it is preferable that the inclined surface 102d on the outer peripheral side and the inclined surface 102f on the inner peripheral side of the protruding portion 102C are extended to the middle blade 102S in order to smoothly discharge chips.

  Further, as another embodiment, as shown in FIG. 9, a blade body portion 202 constituted by only one blade 202 </ b> W may be used. In such a case, the simplest configuration is obtained.

In the embodiment shown in FIG. 8, the main reference number corresponding to the configuration of the blade body according to the first embodiment illustrated in FIGS. 1 to 5 and 7 is 100 as the reference numeral used in the first embodiment. The added reference numerals are attached and detailed description is omitted.
In addition, in the embodiment shown in FIG. 9, 200 is added to the reference numerals used in the first embodiment for the main configuration corresponding to the configuration of the blade body according to the first embodiment illustrated in FIGS. 1 to 5 and 7. A detailed description will be omitted.

  Furthermore, as another embodiment, although not shown in the drawings, a structure in which a first middle blade body part and a second middle blade are provided between an inner blade and an outer blade, or three or more middle blades are provided. Needless to say, the blade portion may be provided.

  By the way, in the said embodiment, although the metal core cutter A was mentioned as an example and demonstrated, this invention is applied also in the case of various core cutters, such as a wood core cutter, a cockleet, and resin. Needless to say, you can.

  The core cutter according to the present invention can be used for various drilling of concrete, stone, wood, metal, resin and the like.

It is a whole side view showing the composition of the outline of the whole core cutter concerning one embodiment of the present invention. It is the figure which looked at the core cutter shown in FIG. 1 from the front end side (II-II arrow direction of FIG. 1). It is the elements on larger scale of the state before planting the blade body part which shows each composition of the crevice formed in the body part for planting the blade body part shown in Drawing 1 and Drawing 2, and the blade body part, (A) is a side view, (b) is a IIIb-IIIb arrow view of (a). The blade part shown in FIG. 1 and FIG. 2 is a partially enlarged view showing a state after being planted in a recess formed in a body part for planting the blade part by a two-dot chain line, (A) is a side view, (b) is an IVb-IVb arrow view of (a). It is a partial expanded sectional view which shows the discharge condition of the chip of a blade body part and a discharge groove part in the state drilled using the core cutter shown in FIGS. It is a partial expanded sectional view which shows the discharge condition of the chip of a blade body part and a discharge groove part in the state drilled using the conventional core cutter. FIG. 5 is an enlarged view of the blade body portion showing the configuration of the blade body portion of the core cutter shown in FIGS. 1 to 4, (a) is a view seen from the front in the rotational direction of the core cutter, (b) is a side view, and (c) ) Is a view from the tip. It is the enlarged view of this blade body part which shows the structure of the blade body part of the core cutter concerning another embodiment, (a) is the figure seen from the rotation direction front of the core cutter, (b) is a side view, (c). Is a view from the tip. Furthermore, it is the enlarged view of this blade body part which shows the structure of the blade body part of the core cutter concerning another embodiment, (a) is the figure seen from the rotation direction front of the core cutter, (b) is a side view, (c) ) Is a view from the tip.

Explanation of symbols

A ... Core cutter
1 ... trunk
1B ... recess
2 ... Blade part
2B ... Base
2p ... Inner surface
3 ... Attachment
4 ... Discharge groove
10: First positioning wall surface
20 ... 2nd positioning wall surface
30: Third positioning wall surface

Claims (5)

A plurality of recesses formed circumferentially apart from each other in order to plant the base of the blade body at the tip of the cylindrical body, a blade body planted in the recess, and a core of the recess In the core cutter provided with a discharge groove formed adjacent to the concave portion in the forward direction of the cutter,
The concave portion, the front end portion of the core cutter in the rotational direction is opened so as to face the discharge groove,
A first positioning wall surface extending in the circumferential direction to contact the inner peripheral surface of the blade body portion is formed in the discharge groove,
A second positioning wall surface with which the base end of the blade body abuts is formed at the base end of the recess,
The core cutter characterized by the 3rd positioning wall surface which the rotation direction rear end of the said blade part contact | abuts in the rotation direction rear end site | part of the said recessed part. The first positioning wall surface is composed of an inclined surface that is inclined toward the inner diameter side on the tip side when viewed from the front in the rotation direction, and an inner peripheral surface of the blade body portion that contacts the first positioning wall surface is the first surface. In addition to the inclined surface corresponding to the inclined surface of the positioning wall,
The contact between the second positioning wall surface and the base end of the blade body portion is contact in a direction that restrains the movement of the blade body portion toward the base end in the axial direction of the core cutter. The core cutter according to claim 1.   The contact between the second positioning wall surface and the base end of the blade body portion is configured to be performed by a surface including a line orthogonal to the axial direction of the core cutter when viewed from the front in the rotation direction. The core cutter according to claim 2. The abutment corresponds to an inclined surface in which the second positioning wall surface is inclined toward the proximal end on the inner diameter side when viewed from the front in the rotation direction, and a proximal end surface of the blade body portion corresponds to the inclined surface of the second positioning wall surface. The core cutter according to claim 2, wherein the core cutter is in contact with an inclined surface. The contact portion of the inner peripheral surface of the blade body portion that contacts the first positioning wall surface and the corresponding portion of the outer peripheral surface of the blade body portion corresponding to the contact portion are inclined surfaces in the same direction. The core cutter according to any one of claims 2 to 4, wherein:

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