JP2022060671A - Cutting edge replaceable drill - Google Patents

Abstract

To provide a cutting edge replaceable drill which enables coupling of a head part to a body part in a stable form regardless of skill of a worker without providing a shank part on the head part in coupling of the head part and the body part.SOLUTION: In a cutting edge replaceable drill 100 having a head part 10 and a body part 50, the head part is provided with a vertical wall face part positioned on a rear side of a flank face adjacent to a cutting edge in a rotation direction of the cutting edge replaceable drill 100, and a curved face part positioned on a rear side of the vertical wall face part and the central side in the rotation direction of the cutting edge replaceable drill 100. The curved face part is composed of a front curved face part, an intermediate curved face part, and a rear curved face part from the tip side of the head part 10.SELECTED DRAWING: Figure 6

Description

The present invention relates to a drill that is integrated by fastening a head part having a cutting edge and a body part having a shank to each other.

Unlike a normal drill (solid drill) in which the cutting edge and shank are physically integrated, the cutting edge and shank are formed as separate parts (head part and body part), and each part is fastened together. In the integrated so-called replaceable cutting edge drill, only the head part can be replaced according to the degree of wear of the cutting edge and the like.

In the replaceable cutting edge drill, the head parts and body parts are fastened together with the head parts fixed to the body parts using fasteners such as screws (screw fastening type) and the head parts and body without using fasteners. There are two types (self-fastening type) in which both parts are fastened only by fitting the parts. For example, a screw fastening type drill is disclosed in Patent Document 1, and a self-fastening type drill is disclosed in Patent Document 2.

A shaft (or protrusion) is provided at the end of the head component (cutting head 12 in the drawing) disclosed in Patent Document 1, and this shaft is a hole (or depression) in the bearing surface provided in the body component. It has a structure that fits into the part). A smooth surface is provided on this shaft, and the head component is fixed by screwing the surface from the outer circumference of the body component.

On the other hand, in the self-fastening type drill disclosed in Patent Document 2, the fastening of the head part and the body part is maintained by the elastic force due to the elastic deformation of both parts. Therefore, a large resistance is generated when the head part is fitted to the body part of the self-fastening type drill, and the head part is attached and detached with a large rotational force (torque) compared to the case of the screw-fastening type drill. However, unlike the screw fastening type drill disclosed in Patent Document 1, since it does not have fastening parts such as screws, it is characterized in that the number of parts is small.

Japanese Patent No. 6399389 Japanese Patent No. 5519694

However, since the drills disclosed in Patent Documents 1 and 2 both have a shaft provided at the lower part of the head component, it is necessary to provide a hole for inserting the shaft in the body component. Therefore, there is a problem that a sufficient wall thickness cannot be secured at the fastening portion (center portion of the drill) between the head component and the body component. In particular, since the drill disclosed in Patent Document 2 has a hole for inserting the shaft of the head component in the central portion of the body component, a sufficient area (smooth surface) to be installed when the head component is attached to the body component is sufficient. Cannot be secured.

As a result, when the head component is attached to the body component, the head component may rotate and be fastened to the body component while the head component is in an unstable posture. At the same time, the final judgment as to whether or not the fastening of the head part and the body part is completed depends largely on the skill of the operator. If the head part and body part are not completely fastened, the head part may come off the body part during use of the drill.

Therefore, it is an object of the present invention to provide a drill with a replaceable cutting edge capable of easily and accurately fastening a head component to a body component regardless of the skill of an operator when fastening the head component and the body component.

The replaceable cutting edge drill of the present invention has a head component having a cutting edge and a body component having a shank as the minimum components. The head component includes a thinning surface located on the central axis side, a bearing surface perpendicular to the axial direction of the head component, a vertical wall surface portion located rearward in the rotational direction of the drill from the flank adjacent to the cutting edge, and thinning. Adjacent to the surface and the seat surface, a curved surface portion located on the rear side and the center side in the rotation direction of the drill is provided, respectively, with respect to the vertical wall surface portion. The curved surface portion is formed in parallel along the central axis of the head component, and is formed in parallel with the front curved surface portion formed adjacent to the thinning surface and the central axis of the head component, and the seat surface. It is divided into an intermediate curved surface portion formed between the rear curved surface portion, the front curved surface portion, and the rear curved surface portion formed adjacent to the head component and inclined toward the central axis side of the head component.

Further, on one end side (opposite side of the shank) of the body component, a seat surface formed over the entire circumference in the radial and circumferential direction of the body component, and two axially extending and facing each other. Each column will be provided. Further, each of these columns has an outer peripheral wall surface portion facing the circumferential direction of the body component and an inner peripheral wall surface portion facing the central axis of the body component.

Then, the vertical wall surface portion of the head component and the outer peripheral wall surface portion of the body component are in contact with each other, the rear curved surface portion of the head component and the inner peripheral wall surface portion of the body component are in contact with each other, and the seat surface of the head component and the seat surface of the body component are in contact with each other. Contacting each other Head parts and body parts are fastened to each other. Further, the intermediate curved surface portion of the head component and the inner peripheral wall surface portion of each column of the body component are separated from each other by a predetermined distance.

In the replaceable cutting edge drill of the present invention, the head component and the body component, which are constituent parts, are provided with a bearing surface radially around the convex portion in the center of the head component and the concave portion in the center of the body component, so that the head component is stable. It can be attached by contacting the seating surface of the body parts in the correct posture. Therefore, the head component can be accurately installed on the body component without depending on the skill of the operator, and can be easily fastened by rotating the head component.

It is a front view of the cutting edge exchange type drill 100. It is a right side view of the cutting edge exchangeable drill 100. It is a top view of the cutting edge exchange type drill 100. FIG. 3 is an enlarged view of the tip of the replaceable cutting edge drill 100 shown in FIG. 1. FIG. 2 is an enlarged view of the tip of the replaceable cutting edge drill 100 shown in FIG. 2. It is a perspective view from the upper side of the tip portion of the cutting edge exchangeable drill 100. It is a perspective view from the lower side of the tip portion of the cutting edge exchangeable drill 100. It is a front view of the head component 10. It is a right side view of a head component 10. It is a top view of the head component 10. It is a bottom view of the head component 10. It is a perspective view from the tip side of a head component 10. It is a perspective view from the rear end side of a head component 10. It is a front view of the body component 50. It is a right side view of a body component 50. It is a top view of the body component 50. FIG. 14 is an enlarged view of a tip portion of a body component 50 shown in FIG. FIG. 15 is an enlarged view of a tip portion of a body component 50 shown in FIG. It is a perspective view from the upper side of the body component 50. It is a perspective view from the lower side of the body component 50.

An embodiment of the replaceable cutting edge drill of the present invention will be described with reference to the drawings. A front view of the replaceable cutting edge drill 100 according to an embodiment of the present invention is shown in FIG. 1, a right side view is shown in FIG. 2, and a plan view is shown in FIG. Further, an enlarged front view of the tip of the replaceable drill 100 of FIG. 1 is shown in FIG. 4, an enlarged right side view of the tip of the replaceable drill 100 of FIG. 2 is shown in FIG. 5, and an enlarged right side view of the replaceable drill 100 is shown above. FIG. 6 shows a perspective view from the tip side), and FIG. 7 shows a perspective view from the lower side (shank side) of the cutting edge replaceable drill 100.

The replaceable cutting edge drill (hereinafter referred to as “drill”) 100 of the present invention is formed by fastening the head component 10 having a cutting edge and the shaft-shaped body component 50 to each other as shown in FIGS. 1 to 3. This is a so-called self-fastening drill. That is, the drill 100 is fastened by fitting each form of the head component 10 and the body component 50 to each other as shown in FIGS. 4 to 7 without using a component such as a screw. Hereinafter, the structures of the head parts and body parts constituting the drill will be described.

8 is a front view of the head component 10 constituting the drill 100 according to the embodiment of the present invention, 9 is a right side view, 10 is a plan view, and 11 is a bottom view. Further, FIG. 12 shows a perspective view of the head component 10 from the front end side, and FIG. 13 shows a perspective view of the head component 10 from the rear end side. The head component 10 that forms a part of the drill of the present invention and substantially carries out the cutting process has two cutting edges 11 and 11 as shown in FIGS. 10 and 12, and is a body component described later. It is attached to one end side (opposite side of the shank) in a removable form.

In the head component 10 shown in FIGS. 9 and 10, in addition to the two cutting edges 11 and 11 like a normal drill, the flanks 12 and 12 and the rake surfaces 13 and 13 connected to the cutting edges 12 and 11 are continuously formed. It is formed. Thinning surfaces 15 and 15 and grooves 14 and 14 connected to the thinning surfaces 15 and 15 are formed on the counter-rotating side of each of the cutting edges 11 and 11 (opposite direction of the arrow shown in FIG. 10: clockwise). ing.

As shown in FIGS. 9, 10 and 12, the head component 10 is formed with a curved surface portion 30 and a vertical wall surface portion 20. The curved surface portion 30 is a curved surface adjacent to each surface of the groove 14, the thinning surface 15, and the seat surface 16, and the vertical wall surface portion 20 is on the rotation direction side with respect to the curved surface portion 30 (direction of arrow shown in FIG. 10: counterclockwise). ) Is the surface. As shown in FIGS. 5 and 6, a part of the curved surface portion 30 and the vertical wall surface portion 20 are portions that come into contact with a part of the body component 50 when the head component 10 is fastened to the body component 50 described later. ..

As shown in FIGS. 9 and 12, the curved surface portion 30 is formed of a front curved surface portion 31, an intermediate curved surface portion 32, and a rear curved surface portion 33, and these curved surface portions are arranged adjacent to each other. The front curved surface portion 31 is located on the tip side (advancing side of the drill) of the head component 10 with respect to the intermediate curved surface portion 32 and the rear curved surface portion 33, and is the center of the head component 10 shown in FIGS. 8 and 9. It is formed so as to be parallel along the axis O1) direction.

At the same time, it is arranged adjacent to the thinning surface 15 located at the tip of the head component 10. The rear curved surface portion 33 is located on the rear end side (drill shank side) of the head component 10 with respect to the front curved surface portion 31, and is a curved surface adjacent to the seat surface 16 as shown in FIG. Similar to 31, as shown in FIG. 12 and the like, they are formed parallel to the direction of the drill axis (central axis O1 of the head component 10 shown in FIGS. 8 and 9). Further, the rear curved surface portion 33 is a portion where the head component 10 and the body component are tightly fastened by coming into contact with the inner peripheral wall surface portion of the column of the body component described later.

The intermediate curved surface portion 32 is a portion formed between the front curved surface portion 31 and the rear curved surface portion 33, and is adjacent to the front curved surface portion 31 on the tip end side (drill advancing side) of the head component 10 and behind the head component 10. On the end side (the shank side of the drill), they are adjacent to the rear curved surface portion 33, respectively. Further, the intermediate curved surface portion 32 is also a curved surface having a shape inclined toward the tip (central axis) side of the drill.

As shown in FIGS. 8 and 9, the vertical wall surface portion 20 is a surface formed in parallel with the central axis O1 of the head component 10, and is formed on the side opposite to the rotation direction of the cutting edge 11. As shown in FIGS. 5 and 6, the role of contacting the inner peripheral wall surface of the column constituting the body component described later and receiving the torque generated by the rotation of the drill (transmitting the rotating force to the head component 10). Fulfill.

Further, as shown in FIGS. 11 and 13, a convex portion 17 is formed on one end side of the head component 10, and when the convex portion 17 is fastened to the body component described later, the convex portion 17 is the center of the seat surface of the body component. It fits into the recess provided in. Around the convex portion 17, a seat surface 16 is integrally formed in the radial direction and the circumferential direction of the head component 10 so as to surround the convex portion 17 so as to be perpendicular to the axial direction of the head component 10. There is. The seat surface 16 of the head component 10 comes into contact with the seat surface of the body component when it is fastened to the body component.

Next, the body parts will be described. A front view of the body component 50 constituting the drill 100 is shown in FIG. 14, a right side view is shown in FIG. 15, and a plan view is shown in FIG. 16, respectively. An enlarged view of the tip portion shown in FIG. 14 is shown in FIG. 17, an enlarged view of the tip portion of the body component 50 shown in FIG. 15 is shown in FIG. A perspective view from the side is shown in FIG. 20, respectively.

As shown in FIGS. 14 to 16, one end side of the body component 50 is a shank 51 attached to a machine tool, and the other end side (opposite side of the shank 51) is two columns 52, 53 extending in the axial direction, and cutting. It has a groove 54 for discharging chips generated during processing. As shown in FIGS. 6 and 7, the groove 54 is formed so as to be connected to the groove 14 of the head component to form a single groove when the body component and the head component are fastened to each other. As shown in FIGS. 16 to 20, the two columns 52 and 53 are located on the outermost peripheral side of the body component 50 in the radial direction, and are arranged so as to face each other.

Further, as shown in FIGS. 16 and 19, a seat surface 56 perpendicular to the axial direction of the body component 50 is provided between the columns 52 and 53. The seat surface 56 is integrally formed so as to surround the recess 57 in the radial direction and the circumferential direction of the body component 50 with the recess 57 as the center. As shown in FIGS. 4 to 7, the seat surface of the head component of the body component 50 comes into contact with (seats) the seat surface 56 of the body component 50 when the head component is fastened. As a result, when the head component is attached to the body component, the head component can be rotated (toward the reverse rotation direction of the replaceable cutting edge drill) and fastened to the body component while the head component remains in a stable posture.

Further, as shown in FIGS. 16 and 19, there is a recess 57 in the center of the seat surface 56 of the body component 50. Therefore, when the seat surface of the head component contacts (seats) the seat surface 56 of the body component 50 at the time of fastening to the head component, the convex portion of the head component fulfills the function of positioning the head component in the radial direction, and the body component. By easily fitting into the recess 57 of the 50, the stable posture of the head component in the body component 50 can be maintained.

Each column 52, 53 of the body component 50 has two sets (two types) of surfaces that come into contact with each other when fastened to the head component. As shown in FIGS. 16 to 20, the first set of surfaces is parallel to the central axis O2 of the body component 50, and the outer peripheral wall surface is formed so that each surface faces the circumferential direction of the body component 50 in a different direction. Parts 62 and 63. The second set of surfaces is curved inner peripheral wall surface portions 72, 73 formed so as to face each other toward the central axis O2 of the body component 50. The inner peripheral wall surface portions 72 and 73 are partially formed with an inclined surface along the front curved surface portion of the head component when the head component and the body component are fastened.

When the head component and the body component 50 are fastened to each other, the outer peripheral wall surface portions 62 and 63 of the body component 50 come into contact with the vertical wall surface portions of the head component, and the inner peripheral wall surface portions 72 and 73 of the body component 50 are head components. It contacts only the rear curved surface. That is, when the head component and the body component are fastened to each other, the intermediate curved surface portions 32 and 32 of the head component and the inner peripheral wall surface portions 72 and 73 of the body component 50 are separated from each other, and the head is separated from each other as shown in FIG. A gap d is provided between the intermediate curved surface portion of the component and the inner peripheral wall surface portion of the body component.

This makes the mounting work difficult because a large contact resistance is generated between the curved surface portion of the head component and the column of the body component when the head component is attached to the body component. Therefore, by providing a gap at this portion, the contact resistance between the parts when the head part is rotated and attached to the body part is reduced, and the attachment work is reduced. Further, when using a drill rotating at high speed, an inertial force (propulsive force) in the axial direction is generated in the head component. Since the intermediate curved surface portion of the head component and a part of the inner peripheral wall surface portion of the body component are inclined to each other, the intermediate curved surface portion of the head component and the inner peripheral wall surface portion of the body component are more closely contacted as the head component is separated from the body component. Then, frictional force works between both sides. As a result, the head component is prevented from coming out of the body component.

Further, the drill of the present invention may be optionally provided with an oil hole (oil hole) for discharging the lubricant. For example, as shown in FIGS. 6 and 19, in the columns 52 and 53 of the body component 50, oil holes 99 and 99 may be provided so that the lubricant is discharged in the direction of the cutting edge when the head component 10 is fastened. good.

As an embodiment of the intermediate curved surface portion of the head component constituting the present invention, the inclination changes at a constant rate when viewed in the axial cross section of the head component 10 as shown in FIGS. 8 and 12. Although it shows a linear linear shape, it has a so-called curved shape (in an axial cross-sectional view) in which the inclination of the head component 10 in the axial direction changes linearly, exponentially, and parabolic. It may be a curved shape).

Further, as shown in FIGS. 11, 13, 16, 16, 19 and the like, the shape of each seat surface of the head component and the body component constituting the present invention is such that the convex portion 17 is centered on the convex portion 17 and the concave portion 57. The shape extends from the periphery of the concave portion 57 to the outer peripheral edge portion of the head component and the body component, but it may be formed at least around the convex portion 17 and the concave portion 57.

10 Head parts 11 Cutting edge 12 Escape surface 13 Scoop surface 14, 54 Groove 15 Thinning surface 16, 56 Seat surface 17 Convex part 20 Vertical wall surface part 30 Curved surface part 31 Front curved surface part 32 Intermediate curved surface part 33 Rear curved surface part 50 Body part 51 Shank 52, 53 Column 57 Recess 62, 63 Outer peripheral wall surface 72, 73 Inner peripheral wall surface 99 Oil hole (oil hole)
100 Replaceable cutting edge drill d Gap between the intermediate curved surface of the head component and the inner peripheral wall surface of the column O1, O2 Central axis

Claims (2)

In a cutting edge replaceable drill having a head component having at least two cutting edges and a body component having a shank, the head component includes a thinning surface located on the central axis side of the head component and the head component. A seat surface perpendicular to the axial direction of the blade, a vertical wall surface portion located behind the flank surface adjacent to the cutting edge in the rotational direction of the replaceable cutting edge drill, and the vertical surface adjacent to the thinning surface and the seat surface. A curved surface portion located on the rear side and the center side in the rotation direction of the drill is provided with respect to the wall surface portion, and the curved surface portion is parallel to the central axis of the head component and adjacent to the thinning surface. It is formed between the front curved surface portion formed by the head component, the rear curved surface portion formed parallel to the central axis of the head component and adjacent to the seat surface, and the front curved surface portion and the rear curved surface portion. It also has an intermediate curved surface portion that is inclined toward the central axis side of the head component, and is formed on one end side of the body component in the radial direction and the circumferential direction of the body component. A seat surface and two columns extending axially from the circumferential peripheral portion of the seat surface of the body component and facing each other are provided, and each column is provided with a circumference of the body component. It has an outer peripheral wall surface portion facing in a direction and an inner peripheral wall surface portion having an inclined surface partially facing the central axis of the body component, and has a vertical wall surface portion of the head component and an outer peripheral wall surface portion of the body component. Contact, the rear curved surface portion of the head component and the inner peripheral wall surface portion of the body component are in contact, and the seat surface of the head component and the seat surface of the body component are in contact with each other, and the intermediate curved surface portion of the head component is in contact with each other. A blade tip exchange type drill characterized in that the head component and the body component are fastened to each other in a state where the inclined surfaces of the inner peripheral wall surface portion of the body component are separated from each other. The seat surface of the head component has a convex portion, and the seat surface of the head component integrally surrounds the convex portion in the radial direction and the circumferential direction of the head component with the convex portion as the center. It is formed and has a recess on the seat surface of the body component so that the seat surface of the body component surrounds the recess in the radial direction and the circumferential direction of the body component with the recess as the center. The first aspect of claim 1, wherein the head component and the body component are integrally formed and the head component and the body component are fastened to each other by contacting the seat surface of the head component and the seat surface of the body component with each other. Cutting edge replaceable drill.

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