JP6852560B2 - Cutting tools and guide pads for cutting tools - Google Patents

Description

The present invention relates to a cutting tool and a guide pad attached to the cutting tool.

Cutting tools capable of efficiently drilling various workpieces (metal workpieces including steel, cast iron, aluminum, stainless steel materials, etc.) are known. This cutting tool is usually equipped with a cutting insert having a cutting edge at the tip of a substantially columnar tool body that rotates around the axis, and the cutting edge of the cutting insert is pressed against the workpiece for cutting. To do.

Among the above cutting tools, deep hole drilling tools that perform deep hole drilling of a predetermined length or longer cause unstable vibration of the tool body during deep hole drilling, resulting in hole diameter expansion and hole swelling. May occur. Therefore, a technique has been proposed in which a guide pad is arranged on the outer peripheral side of the tip of the tool body for the purpose of suppressing the vibration of the tool body generated during machining and aligning the tool body. Since this guide pad can receive the cutting force applied to the cutting edge by being pressed against the inner wall surface of the machined hole during cutting, it is possible to suppress the vibration of the tool body during cutting.

As a cutting tool provided with the guide pad, for example, Patent Document 1 is provided. As shown in FIG. 10A, the guide pad (support pad) described in Patent Document 1 below has a convex outer surface 19 that contacts the inner wall surface of the machined hole and faces the outer surface 19. It has an inner surface 20, a front end surface 21 and a rear end surface 22 located on the front side in the tool traveling direction (direction of arrow A shown in FIG. 10), and a pair of side surfaces 23 and 24 facing each other, and an outer surface 19 and a front end surface 21. An intrusion surface 27 is formed between the two. The intrusion surface 27 is provided to facilitate insertion into a hole formed in the workpiece, and is a boundary line 28 on the front side in the tool traveling direction (hereinafter, also simply referred to as the front side) and the tool traveling direction. It is defined by a boundary line 29 on the rear side (hereinafter, also simply referred to as a rear side) and side boundary lines 30 and 31 facing each other. The rear boundary line 29 of the intrusion surface 27 is connected to the convex outer surface 19, and the front boundary line 28 is connected to the front chamfered flat surface 26. The boundary line 29 on the rear side of the intrusion surface 27 has a bow shape that is convex with respect to the tool traveling direction, and the apex 36 of the bow-shaped line is directed to the front side in the tool traveling direction.

JP-A-2010-142949

By the way, the portion of the workpiece to be drilled by the cutting insert is deformed by thermal expansion during cutting and elastically deformed by the pressing force of the guide pad, but contracts after cutting (after passing through the guide pad). The guide pad described in Patent Document 1 is slidably contacted with the inner wall surface in a state where the outer surface thereof is parallel to the inner wall surface of the machined hole (in other words, the entire outer surface surface of the guide pad is slidably contacted with the inner wall surface). However, if the machined part shrinks as described above after cutting with the cutting insert on the tool tip side, the rear side of the guide pad in the tool traveling direction may be tightened and the movement of the cutting tool in the tool traveling direction may be hindered. was there.

With the intention of solving this problem, there is an idea that the guide pad is attached to the cutting tool in an inclined state so that the rear side of the guide pad in the tool traveling direction does not come into contact with the inner wall surface of the hole. According to this idea, it is possible to eliminate the fact that the rear side of the guide pad is tightened by the above-mentioned contraction and the movement at the time of feeding the tool is hindered. However, when the guide pad is tilted and attached to the cutting tool in this way, the area where the guide pad and the inner wall surface come into contact with each other is larger than that in which the entire outer surface of the guide pad is brought into contact with the inner wall surface of the hole. Since it cannot be sufficiently secured, it may not be possible to sufficiently suppress the runout of the tool body during cutting. In particular, in Patent Document 1, when the technique of tilting the guide pad (support pad) and attaching it to the cutting tool is adopted, the portion of the guide pad that comes into contact with the inner wall surface becomes very small (details are shown in FIG. Of the intrusion surface 27 shown in 10 (A), only the apex 36 of the rear boundary line 29 abuts on the inner wall surface of the hole), so that there is a possibility that the runout of the tool body cannot be sufficiently suppressed.

Therefore, an object of the present invention is to provide a technique capable of stabilizing the behavior of a cutting tool while suppressing the movement of the cutting tool in the traveling direction from being hindered.

The cutting tool according to one aspect of the present invention is a cutting tool provided with a cutting insert arranged at the front end of the tool body and a guide pad that comes into contact with the inner wall surface of the hole cut by the cutting insert. Is a pair of a pair of an outer surface having a cylindrical shape so as to contact the inner wall surface of the hole and an inner surface facing the outer surface, a front end surface located on the front side of the tool body, and a rear end surface facing the front end surface. The guide pad has at least a facing side surface and a connecting surface connecting the outer surface and the front end surface, and the guide pad is attached to the tool body in a state where the rear side in the tool traveling direction is inclined toward the rotation axis side of the tool body. The boundary line between the connecting surface and the outer surface is provided so as to abut against the inner wall surface of the hole, and the boundary line is convex toward the rear end surface side when viewed from the direction facing the outer surface. It is characterized in that it is curved in a shape.

According to this aspect, the rear side of the guide pad in the tool traveling direction is inclined toward the rotation axis side of the tool body (in other words, the rear side of the guide pad in the tool traveling direction is separated from the inner wall surface of the hole than the front side. ) Since it is attached to the tool body, it is possible to prevent the hole machined by the cutting insert from shrinking after cutting (after passing through the guide pad) and tightening the rear side of the guide pad in the tool traveling direction. Therefore, it is possible to prevent the cutting tool from being hindered from moving in the traveling direction. Further, a guide pad is attached to the tool body so that at least the boundary line formed between the intrusion surface and the outer surface abuts on the inner wall surface of the hole, and the boundary line is viewed from the direction facing the outer surface. Occasionally, it is curved convexly toward the rear end face side (in other words, the center side of the guide pad), so it is compared with the configuration that is curved convexly in the direction opposite to the direction toward the center side of the guide pad. Therefore, it is possible to increase the portion of the boundary line that comes into contact with the inner wall surface (in other words, the contact area). Since the guide pad is brought into contact with the inner wall surface in a state where a larger contact area is secured in this way, the behavior of the cutting tool at the time of cutting can be stabilized.

The cutting tool guide pad according to one aspect of the present invention is a cutting tool guide pad attached to a cutting tool for drilling a work piece, and is arranged on the outer peripheral side when attached to the cutting tool. A first end face, a second end face facing the first end face, and a peripheral side surface extending between the first end face and the second end face are provided, and the peripheral side surface is when attached to a cutting tool. It has a front end face arranged on the front side in the tool traveling direction, a rear end face facing the front end face, and a pair of opposite side surfaces extending between the front end face and the rear end face, and has a first end face and a front end face. The connection surface extends between the and, and the boundary line between the connection surface and the first end surface is curved convexly toward the rear end surface side when viewed from the direction facing the first end surface. It is characterized by being.

In the above embodiment, the first end face extends parallel to the axis along the longitudinal direction of the first end face and has a first radius centered on the first axis located below the first end face in the guide pad thickness direction. The connecting surface is a conical surface with a second radius that is located below the first axis in the thickness direction of the guide pad and is larger than the first radius centered on the second axis parallel to the first axis. It may be part of a surface.

In the above aspect, the first end face extends parallel to the axis along the longitudinal direction of the first end face and has a first radius centered on the first axis located below the first end face in the guide pad thickness direction. The connecting surface is a part of a cylindrical surface having a third radius larger than the first radius centered on the third axis intersecting the first axis, and the third axis is from the front end surface to the rear. It may be inclined toward the first end face toward the end face and intersect with the first axis.

In the above aspect, the intrusion surface is a plane extending between the first end surface and the front end surface, and the plane may be inclined toward the rotation axis side of the tool body toward the tool traveling direction.

According to the present invention, it is possible to provide a guide pad for a cutting tool capable of stabilizing the behavior of the cutting tool while suppressing the movement of the cutting tool in the traveling direction from being hindered.

It is a perspective view which shows the schematic structure of the front side of the cutting tool to which the guide pad is attached in this embodiment. It is a schematic side view of the front side of the cutting tool shown in FIG. (A) is a schematic plan view of the guide pad shown in FIG. 1. (B) It is a schematic side view of the guide pad shown in FIG. (A) It is explanatory drawing which shows the state which the guide pad is in contact with the inner wall surface of a hole. (B) It is a figure for demonstrating the contact mark formed on the guide pad. It is a figure for comparing the present embodiment and the conventional example about the contact point between a guide pad and the inner wall surface of a hole. It is a figure for comparing the present embodiment and a conventional example about the wear mark which occurs at the boundary line between an outer surface and an intrusion surface. It is explanatory drawing which shows the state which the guide pad is in contact with the inner wall surface of a hole. (A) It is a schematic plan view of the guide pad in the 1st modification. (B) It is a schematic side view of the guide pad in the 1st modification. (A) It is a schematic plan view of the guide pad in the 2nd modification. (B) It is a schematic side view of the guide pad in the 2nd modification. It is a schematic block diagram which shows the conventional guide pad.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following description of the preferred embodiment is merely an example, and is not intended to limit the present invention, its application, or its use. In addition, the dimensions, shape, angle, etc. of the drawings are exaggerated for convenience of explanation, and may differ from the actual dimensions, shape, angle, etc. Therefore, the technical scope of the present invention is not limited to the dimensions, shapes, angles, etc. of each part shown in these drawings.

First, the configuration of the cutting tool to which the guide pad is mounted according to the present embodiment will be described. FIG. 1 is a schematic perspective view showing a cutting tool, and FIG. 2 is a schematic side view along the direction of arrow A in FIG.

The cutting tool 1 shown in FIGS. 1 and 2 is a tool for drilling a metal work piece, and can be used as a long hole drill for drilling a long hole having a predetermined length or longer, for example. As shown in FIGS. 1 and 2, the cutting tool 1 includes a tool body 2, a cutting insert 4 having a cutting edge 5 attached to the tip side of the tool body 2, and a circumferential surface (side surface) of the tool body 2. ) Is provided with a guide pad 6.

The tool body 2 is made of, for example, steel for machine structure, which is substantially cylindrical, and is configured to be rotatable about the rotation axis C. A cutting insert 4 having a cutting edge 5 is attached to the tip portion 2a of the tool body 2.

As shown in FIG. 1, the cutting insert 4 is attached so that the cutting edge 5 for cutting the work material faces a straight line extending in the radial direction through the rotation axis C. By pressing the cutting tool 1 provided with the cutting insert 4 having such a cutting edge 5 against the work material while rotating it around the rotation axis C by a predetermined drive device, the work material can be easily cut. It is possible.

As shown in FIGS. 1 and 2, the guide pad 6 is arranged on the front side surface of the tool body 2, and has a substantially rectangular parallelepiped shape as a whole. The guide pad 6 is fitted into the concave groove formed on the front side surface of the tool body 2 in a state where the rear side in the tool traveling direction is slightly inclined inward in the radial direction from the front side, and the guide pad 6 is fitted into the through hole 12 (FIG. 3). Etc.), it is fixed with a screw 11 or the like inserted. The guide pad 6 is made of a material containing, for example, cemented carbide. The guide pad 6 has a curved surface whose outer peripheral surface (outer surface 69 of the guide pad 6) is convex outward.

Although FIGS. 1 and 2 show an example in which two guide pads are provided, the present invention is not limited to this example. The number, size, shape, etc. of the guide pads can be appropriately changed as long as the features of the present invention are provided.

The configuration of the guide pad 6 will be further described with reference to FIG. As shown in FIG. 3, the guide pad 6 has an outer surface 69 (first end surface) arranged on the outer peripheral side when attached to the tool body 2 (FIG. 1 and the like) and an inner surface 70 (third surface 70) facing the outer surface 69. (2 end faces) and a peripheral side surface extending between the outer surface 69 and the inner surface 70, and the peripheral side surface has a front end surface 61 and a front end surface 61 arranged on the front side in the tool traveling direction when attached to the tool body 2. It is defined by a rear end surface 62 facing the front end surface 61 and a pair of side surfaces 64 and 65 facing each other extending between the front end surface 61 and the rear end surface 62.

The inner surface 70 is a portion pressed against the bottom of the concave groove formed on the front side surface of the tool body 2.

The outer surface 69 is a cylindrical surface, and the portion of the cylindrical surface located on the central axis X in the longitudinal direction is formed so as to project most upward in the guide pad thickness direction (upward in FIG. 3B). Has been done. Therefore, of the boundary lines 68 described below, the apex 68a located on the central axis X in the longitudinal direction is the most protruding portion upward in the thickness direction of the guide pad.

An example is shown in which the outer surface 69 shown in FIG. 3 or the like is a convex cylindrical surface in order to come into contact with the inner wall surface of the hole when the guide pad 6 is attached to the tool body 2 (FIG. 1 or the like). However, if the boundary line 68 has a shape that is curved in a convex shape (details will be described later), the outer surface 69 is not limited to the cylindrical surface shown in FIG. It may be in shape.

As shown in FIG. 3, an intrusion surface 67 (connecting surface) is formed between the outer surface 69 and the front end surface 61 so that it can be easily inserted into the hole formed by the cutting insert 4. The intrusion surface 67 is a surface that intersects the outer surface 69 and the front end surface 61 at an obtuse angle. In the present embodiment, as shown in FIG. 3, the outer surface 69 extends parallel to the longitudinal center line of the outer surface 69 and is located on the lower side of the outer surface 69 in the guide pad thickness direction. It is a curved surface (cylindrical surface) having a radius R1 (first radius) centered on one axis). The intrusion surface 67 formed between the outer surface 69 and the front end surface 61 is located on the lower side of the guide pad thickness direction (vertical direction in FIG. 3B) than the axis C1 of the outer surface 69 (the axis C2 ( It is a conical surface centered on the second axis) with a radius R2 (second radius) and an angle α as a half apex angle. By forming the outer surface 69 and the intrusion surface 67 in this way, when viewed from the direction facing the outer surface 69 (downward in FIG. 3B), the outer surface 69 which is a cylindrical surface and the intrusion surface 67 which is a conical surface As shown in FIG. 3A, the boundary line 68 with and is curved in a convex shape toward the rear end surface 62 side (in other words, toward the guide pad center side (inside the guide pad)). Have.

The upper direction in the thickness direction of the guide pad indicates an upward direction in FIG. 3 (B), and the lower direction in the thickness direction of the guide pad indicates a downward direction in FIG. 3 (B). That is, the axis C1 (first axis) extends parallel to the axis along the longitudinal direction of the outer surface 69 and is located below the outer surface 69 in FIG. 3 (B).

By the way, the portion of the work material to be drilled by the cutting insert 4 is deformed by thermal expansion during cutting and elastically deformed by the pressing force of the guide pad, but contracts after cutting (after passing through the guide pad). If the guide pad is attached to the cutting tool with its outer surface parallel to the inner wall surface of the hole (in other words, parallel to the traveling direction of the cutting tool), the guide pad shrinks backward in the tool traveling direction. The side may be tightened, which may hinder the smooth movement of the cutting tool in the tool traveling direction.

Therefore, in the present embodiment, as shown in FIG. 4A, the guide pad 6 is attached to the tool body 2 (see FIG. 1) in a state where the rear end side of the guide pad 6 is inclined so as not to contact the inner wall surface of the hole. Install. Specifically, the guide pad 6 is attached to the tool body in a state where the rear side in the tool traveling direction (direction of arrow A shown in FIG. 4A) is inclined so as to be separated from the inner wall surface of the hole than the front side in the tool traveling direction. Has been done. By attaching the guide pad 6 so as to be inclined in this way, the tip end side of the guide pad 6 comes into contact with the inner wall surface of the hole formed in the work material W. Specifically, in the guide pad 6, the periphery of the boundary line 68 formed between the intrusion surface 67 and the outer surface 69 abuts on the inner wall surface of the hole formed in the work material W, and FIG. 4 (B) shows. The contact mark R shown in is formed.

The inclination of the guide pad 6 shown in FIG. 4A is exaggerated for convenience of explanation. The same applies to the inclination of the guide pad 6 of FIG. 7 described below. Further, the region of the contact mark R shown in FIG. 4B is shown as an example, and it is not intended that the contact mark R formed on the guide pad 6 in the present embodiment is limited to the illustrated example. Absent.

By bringing the guide pad 6 into contact with the inner wall surface of the hole in this way, the contact area can be increased as compared with the conventional guide pad. Specifically, in the conventional guide pad, as shown in FIG. 10A, the rear boundary line 29 of the intrusion surface 27 has a bow shape that is convex with respect to the tool traveling direction (upward in FIG. 10). Therefore, the contact point between the boundary line 29 and the inner wall surface of the hole is only the point P2 shown in FIG. 5 (in FIG. 5, the boundary line 29 in the conventional guide pad is indicated by a broken line. ing). On the other hand, in the guide pad 6 of the present embodiment, the boundary line 68 formed between the intrusion surface 67 and the outer surface 69 is directed toward the rear end surface 62 side (in other words, the guide pad center side (guide pad). It has a convexly curved bow shape (inward). Therefore, the contact point between the boundary line 68 and the inner wall surface of the hole is a part of the boundary line 68 passing through the points P1, P2, and P3 shown in FIG. It becomes a region (contact region S shown in FIG. 5) having a predetermined width in the direction opposite to the direction of the arrow A shown in FIG. The distance t shown in FIG. 5 indicates the distance from the tip of the guide pad to the point P2. As shown in the contact area S of FIG. 5, the guide pad 6 in the present embodiment is configured to make surface contact with the inner wall surface of the hole instead of point contact, so that a larger contact area is secured. Since the guide pad 6 can be brought into contact with the inner wall surface in this state, the behavior of the cutting tool at the time of cutting can be stabilized.

The contact region S shown in FIG. 5 is shown as an example, and the contact portion between the guide pad 6 and the inner wall surface in the present embodiment is not limited to the illustrated example. That is, the guide pad according to the present embodiment may be configured to increase the contact area as compared with the configuration in which the guide pad is brought into contact by point contact as in the conventional guide pad described above.

Subsequently, the effect of using the guide pad in this embodiment was verified. FIG. 6 is a diagram for comparing the present embodiment and the conventional example with respect to the wear marks generated on the guide pad when the work material is drilled with a cutting tool. FIG. 6A shows wear marks generated on the guide pad when cutting is performed using the guide pad of the present embodiment. FIG. 6B shows the wear marks generated on the guide pad when cutting is performed using the conventional guide pad shown in FIG. 10 (B). In the conventional guide pad shown in FIG. 10 (B), the shape of the intrusion surface 27B and the boundary line 29B are in the tool traveling direction (direction of arrow A shown in FIG. 10) as compared with the guide pad shown in FIG. 10 (A). ) Is a line perpendicular to (that is, the boundary line 29B is a straight shape), and other shapes (side surfaces 23B, 24B, front end face 21B, etc.) are the conventional guides shown in FIG. 10 (A). Equivalent to a pad.

As shown in FIGS. 6 (A) and 6 (B), the wear marks generated on the guide pad due to the cutting process are generated in a wider area in the present embodiment than in the conventional example. In this embodiment, it can be confirmed that the area of the wear mark is expanded to the range of the reference numeral F shown in FIG. 6 (A)). This is because, in the guide pad 6 of the present embodiment, the boundary line 68 formed between the intrusion surface 67 and the outer surface 69 is directed toward the rear end surface 62 side (in other words, the guide pad center side (guide pad). Since it has a curved shape (inward), it has a boundary line as compared with the guide pad shown in FIG. 10 (A), which has a boundary line 29 that is convexly curved with respect to the tool traveling direction, for example. This is due to the contact with the inner wall surface in a wide range of 68. As is clear from the state of the wear marks generated on the guide pad, the guide pad and the inner wall surface can be brought into contact with each other in a wider area, so that the behavior of the tool body at the time of cutting can be stabilized. In order to stabilize the behavior of the cutting tool, the hole machined by the cutting tool 1 to which the guide pad 6 in the present embodiment is attached and the cutting tool to which the conventional guide pad (for example, the guide pad shown in FIG. 10) is attached are machined. When compared with the holes made, it is possible to make a difference in the roundness of the holes formed in the workpiece.

By the way, as shown in FIG. 7, the hole cut by the cutting tool has an inner wall surface of which is a wall surface having a corrugated cross section (reference numeral Wa shown in FIG. 7) formed by an outer peripheral blade (cutting blade). However, in the present embodiment, the guide pad 6 that receives the cutting force of the outer peripheral blade during cutting slides in a state of being pressed against the inner wall surface of the hole. In this way, since the guide pad 6 slides in a state of being pressed against the inner wall surface, the wall surface having a cross-sectional waveform formed by the outer peripheral blade can be made into a smooth wall surface (reference numeral Wb shown in FIG. 7).

In the conventional guide pad shown in FIG. 10 (A) described above, the boundary line 29 having a convex bow shape with respect to the tool traveling direction is inside the hole at the above-mentioned contact point (point P2 shown in FIG. 5). Since it comes into point contact with the wall surface, vibration of the tool body may occur and the tool may lose its posture. As a result, a margin having a predetermined width (outer peripheral blade margin) from the outer peripheral blade (the cutting edge located on the outer peripheral side of the plurality of cutting edges) toward the rear side in the tool rotation direction comes into contact with the inner wall surface. The outer peripheral blade margin may be chipped (margin chipping), the diameter of the hole formed in the work material may be increased, or the hole may undulate. On the other hand, in the guide pad of the present embodiment, the boundary line 68 has a shape that is convexly curved toward the rear end surface 62 side (in other words, toward the guide pad center side (inside the guide pad)). However, since surface contact can be made at the above-mentioned contact points (contact areas S including points P1, P2, and P3 shown in FIG. 5), the occurrence of vibration of the tool body can be suppressed, and chipping of the outer peripheral blade margin can be performed. It is possible to suppress the occurrence, the expansion of the hole diameter, and the occurrence of hole waviness.

Although the guide pad has been described above, the configuration of the guide pad in the present embodiment is not limited to the above-described configuration, and the boundary line 68 formed between the intrusion surface 67 and the outer surface 69 is the rear end surface. If it has a convexly curved shape toward the 62 side (in other words, toward the center side of the guide pad (inside the guide pad)), it can be appropriately changed to various other configurations. 8 and 9 show a modified example of the guide pad in this embodiment. FIG. 8A shows a schematic plan view of the guide pad in the first modification, and FIG. 8B shows a schematic side view of the guide pad in the first modification. FIG. 9A shows a schematic plan view of the guide pad in the second modification, and FIG. 9B shows a schematic side view of the guide pad in the first modification.

In the guide pad 6B according to the first modification shown in FIG. 8, the outer surface 69B extends parallel to the direction of the longitudinal center line X of the outer surface 69B and is located below the outer surface 69B in the guide pad thickness direction. It is a curved surface (cylindrical surface) having a radius R1 centered on the axis C1. The intrusion surface 67B is a cylindrical surface having a radius R3 (third radius) larger than a radius R1 centered on the axis C3 (third axis) intersecting the axis C1, and more specifically, the axis C3 is a front end surface. It inclines toward the outer surface 69B from 61 toward the rear end surface 62 and intersects the axis C1. By forming the outer surface 69B and the intrusion surface 67B in this way, it is assumed that the direction in which the guide pad 6B is viewed is the front side of the guide pad when viewed from the direction facing the outer surface 69B (as shown in FIG. 8A). When the outer surface 69B is viewed from the front side of the guide pad), the boundary line 68B between the outer surface 69B which is a cylindrical surface having a radius R1 and the intrusion surface 67B which is a cylindrical surface having a radius R3 is on the rear end surface 62 side. Toward (in other words, toward the center side of the guide pad (inside the guide pad)), the shape is convexly curved. Even if the shape of the boundary line 68B is curved so as to be convex toward the rear end surface 62 side, the same effect as that of the first embodiment described with reference to FIGS. 1 to 7 can be obtained. ..

The third axis in the first modification is not limited to the aspect of the axis C3 that intersects the axis C1 shown in FIG. 8, and if the intrusion surface 67B is a cylindrical surface, the third axis is It can be transformed into various other aspects.

In the guide pad 6C according to the second modification shown in FIG. 9, the outer surface 69C is a cylindrical surface having a radius R1 extending parallel to the extending direction of the longitudinal center line X of the outer surface 69C. The intrusion surface 67C is a plane that communicates the outer surface 69C and the front end surface 61, and the plane inclines toward the rotation axis side of the tool body at a predetermined angle α toward the tool traveling direction (leftward in FIG. 9). It is a plane. By forming the outer surface 69C and the intrusion surface 67C in this way, it is assumed that the direction in which the guide pad 6 is viewed is the front side of the guide pad when viewed from the direction facing the outer surface 69C (as shown in FIG. 9A). When the outer surface 69C is viewed from the front side of the guide pad), the boundary line 68C between the outer surface 69C which is a cylindrical surface having a radius R1 and the intrusion surface 67C which is an inclined plane is directed toward the rear end surface 62 side (when In other words, it exhibits a convexly curved shape toward the center side of the guide pad (inward of the guide pad). Even if the shape of the boundary line 68C is curved so as to be convex toward the rear end surface 62 side, the same effect as that of the first embodiment described with reference to FIGS. 1 to 7 can be obtained. ..

The boundary line formed between the outer surface and the intrusion surface of the guide pad, which has been described with reference to FIGS. 3, 8 and 9, is toward the rear end surface side (in other words, the guide pad center side). As long as it has a shape that is curved convexly (toward the inside of the guide pad), it can be changed to various other shapes, sizes, and the like.

The embodiments described above are for facilitating the understanding of the present invention, and are not for limiting and interpreting the present invention. Each element included in the embodiment and its arrangement, material, condition, shape, size, and the like are not limited to those exemplified, and can be changed as appropriate. In addition, the configurations shown in different embodiments can be partially replaced or combined.

1 ... Cutting tool 2a ... Tip 4 ... Cutting insert 5 ... Cutting edge 6, 6B, 6C ... Guide pad 11 ... Screw 61 ... Front end face 62 ... Rear end face 64 ... Side surface 67, 67B, 67C ... Intrusion surface 68, 68B, 68C ... Boundary lines 69, 69B, 69C ... Outer surface 70 ... Inner surface C ... Rotation axis C1 of the tool body ... First axis C2 ... Second axis C3 ... Third axis

Claims (2)

A guide pad for cutting tools that is attached to cutting tools that drill holes in workpieces.
A first end face arranged on the outer peripheral side when attached to the cutting tool and a second end face facing the first end face,
A peripheral side surface extending between the first end surface and the second end surface is provided.
The peripheral side surface is a pair extending between a front end surface and a rear end surface facing the front end surface, which are arranged on the front side in the tool traveling direction when attached to the cutting tool, and between the front end surface and the rear end surface. With opposite sides of
A connecting surface extends between the first end surface and the front end surface.
The boundary line between the connecting surface and the first end surface is curved in a convex shape toward the rear end surface side when viewed from the direction facing the first end surface.
The first end face extends parallel to the axis along the longitudinal direction of the first end face and has a first radius centered on the first axis located below the first end face in the guide pad thickness direction. It is a cylindrical surface and
The connecting surface is a conical surface having a second radius larger than the first radius centered on a second axis parallel to the first axis and located below the first axis in the guide pad thickness direction. Characterized by being part ,
Off-cutting guide pad tool. A guide pad for cutting tools that is attached to cutting tools that drill holes in workpieces.
A first end face arranged on the outer peripheral side when attached to the cutting tool and a second end face facing the first end face,
A peripheral side surface extending between the first end surface and the second end surface is provided.
The peripheral side surface is a pair extending between a front end surface and a rear end surface facing the front end surface, which are arranged on the front side in the tool traveling direction when attached to the cutting tool, and between the front end surface and the rear end surface. With opposite sides of
A connecting surface extends between the first end surface and the front end surface.
The boundary line between the connecting surface and the first end surface is curved in a convex shape toward the rear end surface side when viewed from the direction facing the first end surface.
The first end face extends parallel to the axis along the longitudinal direction of the first end face and has a first radius centered on the first axis located below the first end face in the guide pad thickness direction. It is a cylindrical surface and
The connecting surface is a part of a cylindrical surface having a third radius larger than the first radius centered on the third axis intersecting the first axis.
The third axis is inclined in a direction approaching the first end surface from the front end surface toward the rear end surface and intersects with the first axis .
Off-cutting guide pad tool.

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