JP2022041951A - Grooving tool - Google Patents

Abstract

To make it possible to eject a coolant accurately near a cutting blade.SOLUTION: A grooving tool comprises a cutting insert, a holder 3, and a coolant channel 4. The holder 3 has an insert attachment seat 35, and jaw parts 36 which are located above and below the insert attachment seat 35, and fix the cutting insert. The jaw part 36 has a curved shape when viewed from a tool tip side, and becomes thinner as separating from the insert attachment seat 35. The coolant channel 4 has a jaw part channel 43 which extends in the jaw part 36. The jaw part channel 43 has: a vertically long guide channel part 44 having dimension in a vertical direction compared to dimension in a tool width direction in a channel cross section; and a laterally long ejection channel part 45 having dimension in the tool width direction compared to dimension in the vertical direction in a channel cross section.SELECTED DRAWING: Figure 4A

Description

The present invention relates to a grooving tool.
This application claims priority based on Japanese Patent Application No. 2020-145526 filed in Japan on August 31, 2020, the contents of which are incorporated herein by reference.

Grooving tools for grooving the end face and peripheral surface of a work material are known. The grooving tool comprises a cutting insert with a cutting edge, a holder for holding the cutting insert, and a coolant flow path extending inside the holder. The holder has an insert mounting seat on which the cutting insert is located and a pair of jaws arranged above and below the insert mounting seat and in vertical contact with the cutting insert. As a conventional grooving tool, for example, the one described in Patent Document 1 is well known.

Japanese Unexamined Patent Publication No. 2015-933380

For example, in a grooving tool for end face grooving, the jaw portion may be formed in a curved shape when viewed from the tool tip side. In this case, the thickness of the jaw portion decreases as the distance from the insert mounting seat increases in the vertical direction. With such a grooving tool, it is difficult to provide a coolant flow path having a desired shape in the jaw.

For example, when trying to supply coolant to the vicinity of the cutting edge through the flank of the cutting insert, the coolant flow path should be set on the tool tip side in the jaw so that the vicinity of the ejection port of the coolant flow path has an inclination close to the flank. It is necessary to incline at an angle toward the upper side as it goes toward. However, there are various restrictions due to the thin part of the jaw and the curved shape, and there is no choice but to reduce the cross-sectional area of the coolant flow path, or the coolant flow path cannot be sufficiently inclined. Occurs.

That is, if an attempt is made to accurately eject the coolant near the cutting edge by passing the coolant flow path through the thin portion of the jaw, the flow path cross-sectional area of the coolant flow path must be reduced, and the coolant flow rate must be reduced. Decreases. Further, if an attempt is made to secure a large flow path cross-sectional area of the coolant flow path by passing the coolant flow path through the thick portion of the jaw, it becomes difficult to incline the coolant flow path near the ejection port, and the coolant Cannot be ejected accurately near the cutting edge.

One of the objects of the present invention is to provide a grooving tool capable of accurately ejecting coolant in the vicinity of a cutting edge while ensuring a coolant flow rate.

One aspect of the grooving tool of the present invention includes a cutting insert having a cutting edge, a holder for holding the cutting insert, and a coolant flow path extending inside the holder. The cutting edge has a cutting edge portion extending in the tool width direction, and the holder has an insert mounting seat on which the cutting insert is arranged and a pair of jaw portions arranged on the upper side and the lower side of the insert mounting seat. These jaws come into contact with the cutting insert from above and below. At least one of the jaws has a plate shape that expands in the direction perpendicular to the tool width direction, and extends in a curved shape when viewed from the tool tip side, and the plate thickness decreases as the distance from the insert mounting seat increases in the vertical direction. .. The coolant flow path has a jaw flow path that extends inside the at least one jaw. The jaw flow path includes a vertically long guide flow path portion in which the cross section of the flow path is larger in the vertical direction than the dimension in the tool width direction, and a ejection flow path portion communicating with the guide flow path portion. Have. The ejection flow path portion is arranged closer to the insert mounting seat on the tool tip side and in the vertical direction than the guide flow path portion, and opens at the end portion of the jaw portion on the tool tip side. The ejection flow path portion has a horizontally long cross section, and the dimension in the tool width direction is larger than the dimension in the vertical direction. In the present specification, the "cross section" of the guide flow path portion and the ejection flow path portion both indicate a cross section appearing in a virtual plane perpendicular to the axial direction of the holder.

According to the grooving tool of the above aspect, even if the jaw portion for clamping the cutting insert has a curved plate shape in which the plate thickness becomes thinner as it moves away from the insert mounting seat in the vertical direction, the jaw portion extending in the jaw portion. Coolant can be ejected accurately and stably toward the vicinity of the cutting edge.

Specifically, among the jaw flow paths, the flow path cross section of the ejection flow path portion that opens at the end of the jaw on the tool tip side has a horizontally long shape in which the dimension in the tool width direction is larger than the dimension in the vertical direction. , This ejection flow path portion is arranged in the thick part of the jaw portion, that is, the portion close to the insert mounting seat, and is stable over a wide range from the ejection flow path portion to at least the entire cutting edge including the cutting edge portion. The coolant can be ejected.

Further, since the cross section of the guide flow path of the jaw flow path has a vertically long shape in which the dimension in the vertical direction is larger than the dimension in the tool width direction, this guide flow path portion is inserted into the jaw portion. It is possible to place it in a part with a thin plate thickness (thin-walled part) away from the seat in the vertical direction. That is, since the guide flow path portion can be arranged in the thin-walled portion of the jaw portion while the flow path cross-sectional area of the guide flow path portion is largely secured, that is, the flow rate of the coolant ejected from the jaw portion is secured. The shape of the flow path from the guide flow path portion to the ejection flow path portion can be easily tilted at an angle in the vertical direction toward the tool tip side. Therefore, it becomes easy to arrange the cutting edge in the vicinity of the extension line of the opening (spouting outlet) of the ejection flow path portion, and the coolant can be accurately and efficiently supplied in the vicinity of the cutting edge.

In the grooving tool, the jaw flow path may be provided in each of the jaws.

In this case, of the pair of jaws, the coolant can be ejected from the jaw flow path of the upper jaw located above the insert mounting seat through the rake face of the cutting insert in the vicinity of the cutting edge. Further, among the pair of jaws, the coolant can be ejected from the jaw flow path of the lower jaw located below the insert mounting seat through the flank of the cutting insert and in the vicinity of the cutting edge. Therefore, the coolant can be supplied more stably to the vicinity of the cutting edge.

In the grooving tool, the flow path cross-sectional area of the ejection flow path portion may be smaller than the flow path cross-sectional area of the guide flow path portion.
In the grooving tool, the flow path cross-sectional area of the guide flow path portion and the flow path cross-sectional area of the ejection flow path portion may be the same as each other.

For example, unlike the above configuration, if the flow path cross-sectional area of the ejection flow path portion is larger than the flow path cross-sectional area of the guidance flow path portion, the flow path is interrupted when the coolant flows from the guidance flow path portion to the ejection flow path portion. As the area increases, the flow velocity may decrease and pressure loss may occur.
On the other hand, according to any of the above configurations, when the coolant flows from the guide flow path portion to the ejection flow path portion, a decrease in the flow velocity, a pressure loss, or the like can be suppressed. The flow velocity of the coolant flowing through the ejection flow path portion is stably increased, and the coolant ejected from the ejection flow path portion can efficiently cool the vicinity of the cutting edge.

In the grooving tool, the maximum value of the ratio (a / b) of the vertical dimension (a) to the vertical dimension (b) in the flow path cross section of the guide flow path portion is 1.2 or more and 5 It may be 0.0 or less.
Further, the ratio (a / b) of the guide flow path portion may be reduced toward the tool tip side.

In the flow path cross section of the guide flow path portion, when the maximum value of the ratio (a / b) of the vertical dimension (a) to the dimension (b) in the tool width direction is 1.2 or more, the guide flow The cross section of the flow path of the road portion is stable and has a vertically long shape, and it is easy to arrange this guide flow path portion in the thin-walled portion of the jaw portion. Therefore, the above-mentioned action and effect of the present invention can be obtained more stably.
Further, when the maximum value of the ratio (a / b) is 5.0 or less, it is possible to suppress problems such as an increase in pressure loss due to the shape of the cross section of the flow path being too flat in the vertical direction.
Further, when the ratio (a / b) of the guide flow path portion is reduced toward the tool tip side, the change in the cross-sectional shape of the guide flow path portion is smooth, so that the guide flow path portion is described. The flow path resistance of the flow path portion can be suppressed to a small value.

In the grooving tool, the maximum value of the ratio (b / a) of the ratio (b / a) of the dimension (b) in the tool width direction to the dimension (a) in the vertical direction is 1.2 or more in the flow path cross section of the ejection flow path portion. It may be 0.0 or less.
Further, the ratio (b / a) of the ejection flow path portion may be increased toward the tool tip side.

When the maximum value (b / a) of the ratio (b / a) of the dimension (b) in the tool width direction to the dimension (a) in the vertical direction in the cross section of the flow path of the ejection flow path portion is 1.2 or more, the ejection flow path is described. The cross section of the flow path of the portion is stable and has a horizontally long shape, and it is easy to stably eject the coolant from the ejection flow path portion over the entire cutting edge. Therefore, the above-mentioned action and effect of the present invention can be obtained more stably.
If the maximum value of the ratio (b / a) is 5.0 or less, the shape of the cross section of the flow path is too flat and the coolant is ejected in the form of mist, so that the coolant is other than the cutting edge. It is possible to suppress the trouble of being unnecessarily dissipated in the part of.
Further, when the ratio (b / a) of the ejection flow path portion is increased toward the tool tip side, the change in the cross-sectional shape of the ejection flow path portion is smooth, so that the ejection flow path portion is ejected. The flow path resistance of the flow path portion can be suppressed to a small level.

In the grooving tool, the cross section of each flow path of the guide flow path portion and the ejection flow path portion may be elliptical.

In the grooving tool, the cross section of each flow path of the guide flow path portion and the ejection flow path portion may be a polygonal shape such as a triangular shape, a quadrangular shape, a pentagonal shape, or a hexagonal shape.

According to the grooving tool of the above aspect of the present invention, the coolant can be accurately ejected in the vicinity of the cutting edge while ensuring the coolant flow rate.

FIG. 1 is a perspective view showing a grooving tool according to an embodiment of the present invention. FIG. 2 is a front view of the grooving tool of the present embodiment as viewed from the tool tip side. FIG. 3 is a side view of the head member of the holder of the present embodiment as viewed from the tool width direction. FIG. 4A is a cross-sectional view showing the IV-IV cross section of FIG. FIG. 4B is a partial cross-sectional view showing a part of FIG. 4A in an enlarged manner. FIG. 5A is a cross-sectional view showing a VV cross section of FIG. FIG. 5B is a partial cross-sectional view showing a part of FIG. 5A in an enlarged manner. FIG. 6A is a cross-sectional view showing the VI-VI cross section of FIG. FIG. 6B is a partial cross-sectional view showing a part of FIG. 6A in an enlarged manner. FIG. 7A is a cross-sectional view showing a cross section of FIG. 3 VII-VII. FIG. 7B is a partial cross-sectional view showing a part of FIG. 7A in an enlarged manner. FIG. 8A is a cross-sectional view showing a cross section of FIG. 3 VIII-VIII. FIG. 8B is a partial cross-sectional view showing a part of FIG. 8A in an enlarged manner. FIG. 9 is a perspective view showing a head member of a holder of a modified example of the present embodiment. FIG. 10 is a side view of the head member of the holder of the modified example of the present embodiment as viewed from the tool width direction. 11A is a cross-sectional view showing the XI-XI cross section of FIG. 11B is a partial cross-sectional view showing a part of FIG. 11A in an enlarged manner. FIG. 12A is a cross-sectional view showing a cross section of XII-XII of FIG. FIG. 12B is a partial cross-sectional view showing a part of FIG. 12A in an enlarged manner. FIG. 13A is a cross-sectional view showing a cross section of XIII-XIII of FIG. FIG. 13B is a partial cross-sectional view showing a part of FIG. 13A in an enlarged manner.

The grooving tool 1 according to an embodiment of the present invention will be described with reference to the drawings. The grooving tool 1 of the present embodiment is a cutting tool used for turning such as grooving and parting off. The grooving tool 1 is detachably attached to a tool post or the like of a machine tool such as a lathe (not shown). Specifically, the grooving tool 1 of the present embodiment is a cutting edge exchange type grooving tool for end face grooving.

As shown in FIGS. 1 and 2, the grooving tool 1 is composed of an elongated rectangular cutting insert 2 having a cutting edge 21 at the tip thereof and a holder 3 for holding the cutting insert 2. The holder 3 includes a square bar-shaped shank portion 31 attached to a tool post or the like, a head member 32 that sandwiches and fixes the cutting insert 2, and a coolant flow path 4 that extends inside the holder 3 and supplies coolant to the cutting edge 21. A fixing screw 8 and a fastening screw 11 for fixing the head member 32 to the shank portion 31 are provided. The head member 32 is detachably attached to the first end portion 31a of both ends (first end portion 31a and second end portion 31b) of the shank portion 31, and the cutting edge 21 protrudes from the first end portion 31a. The cutting insert 2 is held so as to.

[Definition of direction]
In this embodiment, the XYZ Cartesian coordinate system is set and each configuration is described.
The X-axis direction is the direction in which the central axis of the shank portion 31 extends, that is, the direction in which the holder 3 extends, and corresponds to the axial direction (longitudinal direction) of the grooving tool 1. Of the axial directions, the direction (+ X side) from the second end 31b of the shank 31 toward the first end 31a where the head member 32 is arranged is called the tip side, and the first end 31a to the second end The direction toward the portion 31b (-X side) is called the rear end side. In the present embodiment, the cutting insert 2 is held by the head member 32 in a posture in which the cutting edge 21 is projected from the tip end portion of the head member 32 toward the tip end side. Therefore, the tip side may be paraphrased as the protruding direction.

The Y-axis direction is a direction orthogonal to the X-axis direction. The Y-axis direction is the direction in which the pair of side surfaces of the shank portion 31 faces, that is, the direction in which the pair of side surfaces of the holder 3 faces, and corresponds to the tool width direction (left-right direction) of the grooving tool 1. The tool width direction may be paraphrased as the first direction. The head member 32 is arranged in the recess 31f formed in the first side surface 31c of the pair of side surfaces (first side surface 31c and second side surface 31d) of the shank portion 31. Of the tool width directions, the direction (+ Y side) from the second side surface 31d of the shank portion 31 toward the first side surface 31c where the head member 32 is arranged is called the right side, and is directed from the first side surface 31c to the second side surface 31d. The direction (-Y side) is called the left side. The right side may be paraphrased as one side in the first direction. The left side may be paraphrased as the other side in the first direction.

The Z-axis direction is a direction orthogonal to the X-axis direction and the Y-axis direction. The Z-axis direction is the direction in which the top surface and the bottom surface of the shank portion 31 face, that is, the direction in which the top surface and the bottom surface of the holder 3 face, and corresponds to the vertical direction (height direction) of the grooving tool 1. The vertical direction may be paraphrased as the second direction. Of the vertical directions, the direction in which the rake face 22 of the cutting insert 2 faces (+ Z side) is called the upper side, and the direction opposite to the direction in which the rake face 22 faces (−Z side) is called the lower side. The upper side may be paraphrased as one side in the second direction. The lower side may be paraphrased as the other side in the second direction.

In the present embodiment, the left side, the right side, the upper side, and the lower side are names for simply explaining the relative positional relationship of each part, and the arrangement relationship at the time of actual use is other than the arrangement relationship indicated by these names. It may be the arrangement of.

〔holder〕
The shank portion 31 is made of a metal such as steel. The first end portion 31a of the shank portion 31 has a larger dimension in the vertical direction and a dimension in the tool width direction than the portion other than the first end portion 31a. The portion of the shank portion 31 other than the first end portion 31a is a prismatic shape extending in the axial direction.

The shank portion 31 has a recess 31f. The recess 31f is a recess that is recessed to the left from the first side surface 31c facing the right side of the shank portion 31. The recess 31f is arranged at the distal end of the first side surface 31c. The recess 31f is a notch that opens toward the right side, the tip side, and the upper side in the shank portion 31. The recess 31f is composed of a plurality of wall surfaces (inner wall surfaces) including at least one wall surface facing to the right.

The recess 31f has a mounting surface 31e. The mounting surface 31e is arranged on the wall surface facing the right side in the recess 31f. The mounting surface 31e has a planar shape extending in the direction perpendicular to the tool width direction.

The head member 32 is made of metal. The head member 32 may be formed by casting or machining, but may be formed, for example, by laminating the metal powder material while melting it using a 3D printer. The head member 32 is fixed to the first end portion 31a, that is, the tip portion of the shank portion 31 by screwing with a fixing screw 8 and a fastening screw 11.
As shown in FIGS. 1 to 3, the head member 32 has a plate-shaped head main body 33 and a plate-shaped head fixing plate 34 extending vertically from the head main body 33 to the left side.

The head main body 33 has a plate shape that extends in the direction perpendicular to the tool width direction as a whole, and a part of the head main body 33 is arranged in the recess 31f. Of the pair of plate surfaces facing the tool width direction of the head body 33, the plate surface 33a facing the left side comes into contact with the mounting surface 31e of the recess 31f.

The head body 33 includes an insert mounting seat 35 on which the cutting insert 2 is arranged, a pair of jaws 36 that come into contact with the cutting insert 2 from above and below, and a pair of slits 37 formed between the jaws 36. It has a connecting portion 38 that elastically connects the jaw portion 36, and a first screw insertion hole 39 for inserting a part of the fixing screw 8. In this embodiment, a pair of jaw portions 36 having a jaw flow path are provided vertically, but in the present invention, the jaw portion having the jaw flow path is at least either the upper side or the lower side of the insert mounting seat 35. It suffices to be arranged in a crab, and the jaw portion having the jaw passage is in the shape of a plate extending in the direction perpendicular to the tool width direction. The holder 3 of this embodiment has an insert mounting seat 35 and a jaw portion 36 for fixing the cutting insert 2 in the insert mounting seat 35.
In this embodiment, a pair of jaw portions 36 are provided on the upper side and the lower side of the insert mounting seat 35. Of these pair of jaws 36, one jaw 36 located above the insert mounting seat 35 is the upper jaw 36a, and the other jaw 36 located below the insert mounting seat 35 is the lower jaw. 36b.

The insert mounting seat 35 is located on the tip end side portion of the head body 33. That is, the insert mounting seat 35 is arranged at the tip of the holder 3. The insert mounting seat 35 has a notch shape or a slit shape that opens to the tip side, the left side, and the right side in the head main body 33. The cutting insert 2 is detachably mounted on the insert mounting seat 35.
As shown in FIG. 3, the insert mounting seat 35 has a pressing surface 35a that abuts on the upper surface of the cutting insert 2, a pedestal surface 35b that supports the lower surface of the cutting insert 2, and an abutting surface that abuts the rear end of the cutting insert 2. It has a surface 35c.

The pressing surface 35a is composed of the lower surface of the upper jaw portion 36a. The pressing surface 35a has a V-shape having a cross-sectional shape perpendicular to the axial direction (X-axis direction) over the entire length thereof, which is convex downward. The pressing surface 35a contacts the upper surface of the cutting insert 2 and presses the cutting insert 2 from above.

The pedestal surface 35b is composed of the upper surface of the lower jaw portion 36b. The pedestal surface 35b has a V-shape whose cross-sectional shape perpendicular to the axial direction is convex upward over the entire length. The pedestal surface 35b contacts the lower surface of the cutting insert 2 and supports the cutting insert 2 from below.

The abutting surface 35c is arranged at the rear end of the insert mounting seat 35 and faces the tip end side. The abutting surface 35c has a planar shape substantially perpendicular to the axial direction. The abutting surface 35c contacts the rear end surface of the cutting insert 2 and supports the cutting insert 2 from the rear end side.

As shown in FIG. 2, the pair of jaws 36 have a curved shape so that the left side surface is convex and the right side surface is concave when viewed from the tool tip side, and the plate thickness increases as the distance from the insert mounting seat 35 increases in the vertical direction. Becomes thinner. Specifically, the upper jaw portion 36a becomes thinner as it moves upward from the insert mounting seat 35, and the lower jaw portion 36b becomes thinner as it moves downward from the insert mounting seat 35. In the present embodiment, the upper jaw portion 36a is curved so as to be located on the right side as it goes upward from the insert mounting seat 35, and the lower jaw portion 36b is curved so as to be located on the right side as it goes downward from the insert mounting seat 35. is doing.

As shown in FIG. 3, the upper jaw portion 36a has a smaller vertical dimension toward the tip end side of the holder 3, and the lower jaw portion 36b also has a smaller vertical dimension toward the tip end side of the holder 3. The lower jaw portion 36b protrudes toward the tip end side of the holder 3 from the upper jaw portion 36a. The vertical dimension of the lower jaw portion 36b is larger than the vertical dimension of the upper jaw portion 36a at the opposite position.

The slit 37 is arranged on the rear end side of the insert mounting seat 35 and is connected to the insert mounting seat 35. The slit 37 extends in the axial direction of the holder 3 together with the insert mounting seat 35 so as to divide the head main body 33 into an upper portion and a lower portion. The slit 37 has a slit shape that opens to the left and right sides of the head body 33.

The connecting portion 38 is arranged at the rear end side portion of the head main body 33 at a position corresponding to the end of the slit 37, and connects the upper portion of the head main body 33 including the upper jaw portion 36a and the lower portion including the lower jaw portion 36b. .. The connecting portion 38 is elastically deformable. The elastic deformation of the connecting portion 38 changes the vertical distance between the lower surface of the upper jaw portion 36a and the upper surface of the lower jaw portion 36b. That is, the connecting portion 38 connects the upper jaw portion 36a and the lower jaw portion 36b so as to be elastically displaceable in the vertical direction.

The first screw insertion hole 39 is arranged in the rear end side portion of the head main body 33. The first screw insertion hole 39 penetrates the head body 33 in the tool width direction (Y-axis direction). That is, the first screw insertion hole 39 penetrates the head body 33 in the plate thickness direction. A plurality of first screw insertion holes 39 are provided, and in this embodiment, two first screw insertion holes 39 are formed at intervals in the vertical and front-rear directions.

As shown in FIG. 2, the head fixing plate 34 projects to the left from a substantially central portion in the front-rear direction of the head main body 33. The head fixing plate 34 has a plate shape that extends in a direction perpendicular to the axial direction (X-axis direction). The head fixing plate 34 has a plurality of second screw insertion holes 34a, and in this embodiment, two second screw insertion holes 34a are formed so as to be vertically spaced apart from each other.

The second screw insertion hole 34a penetrates the head fixing plate 34 in the axial direction of the holder 3. That is, the second screw insertion hole 34a penetrates the head fixing plate 34 in the plate thickness direction.

[Cutting insert]
As shown in FIGS. 1 and 2, the cutting insert 2 is axially extending or columnar. The cutting insert 2 of this embodiment has a substantially square columnar shape. The cutting insert 2 is inserted into the insert mounting seat 35 of the head member 32 from the front and is detachably attached. The cutting insert 2 has a rake face 22, a flank face 23, and a cutting edge 21.

The rake face 22 is located at the front end of the cutting insert 2 and faces upward. The rake face 22 has a rectangular shape when viewed from above.
The flank 23 is arranged at the front end of the cutting insert 2. The flank 23 has a surface facing the front end side (front flank surface), a surface facing the left side and a surface facing the right side (a pair of side flank surfaces).

The cutting edge 21 is located at the ridgeline where the rake face 22 and the three flanks 23 are connected to each other. The cutting edge 21 is arranged so as to project from the head main body 33 to the tip side, the left side, and the right side.
In the present embodiment, the cutting edge 21 has a front blade 21a and a pair of side blades. The front blade 21a extends in the tool width direction (Y-axis direction). That is, the cutting edge 21 has a cutting edge portion 21a extending in the tool width direction. The pair of side blades are connected to both ends of the front blade 21a in the tool width direction and extend from each end toward the rear end side. Therefore, the cutting edge 21 has a substantially U-shape when viewed from above.
The cutting insert 2 of the present embodiment has a pair of a rake face 22, a flank face 23, and a cutting edge 21 at both ends of the cutting insert 2 in the axial direction.

[Fixing screw]
The fixing screw 8 fixes the head member 32 to the tip of the shank portion 31. A plurality of fixing screws 8 are provided. In this embodiment, the plurality of fixing screws 8 include two first fixing screws 8a and two second fixing screws 8b.
The first fixing screw 8a fixes the head body 33 to the right side surface of the shank portion 31. The first fixing screw 8a is inserted into the first screw insertion hole 39 of the head main body 33, and is screwed into the first screw hole (not shown) of the shank portion 31. It is preferable that a plurality of first fixing screws 8a are provided.
The second fixing screw 8b fixes the head fixing plate 34 to the front end surface of the shank portion 31. The second fixing screw 8b is inserted into the second screw insertion hole 34a of the head fixing plate 34, and is screwed into the second screw hole (not shown) of the shank portion 31. It is preferable that a plurality of second fixing screws 8b are provided.

[Fastening screw]
The fastening screw 11 has a function of fixing the head member 32 to the upper surface of the front end portion of the shank portion 31 and fixing the cutting insert 2 to the insert mounting seat 35. The fastening screw 11 is screwed into a third screw hole (not shown) formed on the upper surface of the front end portion of the shank portion 31 in a state where the upper portion of the head body 33 including the upper jaw portion 36a is pressed downward. .. When the fastening screw 11 is tightened, the upper portion of the head body 33 is pressed downward to elastically deform the connecting portion 38, and the upper jaw portion 36a is displaced downward. As a result, the cutting insert 2 arranged on the insert mounting seat 35 is clamped between the lower surface of the upper jaw portion 36a (pressing surface 35a) and the upper surface of the lower jaw portion 36b (pedestal surface 35b).

[Coolant flow path]
The coolant flow path 4 extends over the inside of the shank portion 31 and the inside of the head member 32. Although not shown, the shank portion flow path extending inside the shank portion 31 of the coolant flow paths 4 is connected to a hose or the like of a coolant supply means of a machine tool. Of the coolant flow paths 4, the head member flow path 41 extending inside the head member 32 is specifically arranged in the head main body 33. Coolant supplied from the coolant supply means circulates inside the coolant flow path 4.

As shown in FIGS. 1 to 3, the head member flow path 41 communicates with the connection flow path 42 connected to the shank portion flow path and the connection flow path 42, and extends inside the jaw portion 36. It has 43 and. That is, the coolant flow path 4 has a connection flow path 42 and a jaw flow path 43.

The connection flow path 42 extends in the tool width direction. A pair of connection flow paths 42 are provided in the head main body 33 at intervals in the vertical direction. Of the pair of connection flow paths 42, one connection flow path 42 arranged at the upper part of the head main body 33 is the upper connection flow path 42a, and the other connection flow path 42 arranged at the lower part of the head main body 33 is. , The lower connection flow path 42b.

The upper connecting flow path 42a has a circular shape in the cross section of the flow path perpendicular to the tool width direction. The upper connection flow path 42a opens on the upper side of the plate surface 33a facing the left side of the head main body 33. The inner diameter of the upper connecting flow path 42a becomes smaller toward the right side from the opening opened in the plate surface 33a. That is, the cross-sectional area of the upper connecting flow path 42a becomes smaller toward the right side.

The lower connecting flow path 42b has a circular shape in the cross section of the flow path perpendicular to the tool width direction. The lower connection flow path 42b opens to the lower side of the plate surface 33a facing the left side of the head main body 33. The inner diameter of the lower connecting flow path 42b becomes smaller toward the right side from the opening opened in the plate surface 33a. That is, the cross-sectional area of the lower connecting flow path 42b becomes smaller toward the right side.

The jaw flow path 43 extends from a position connected to the connection flow path 42 in a direction perpendicular to the tool width direction. Specifically, the jaw flow path 43 extends from the connection portion with the connection flow path 42 toward the tool tip side so as to approach the insert mounting seat 35. In this embodiment, a pair of jaw flow paths 43 are provided on the head body 33 at intervals in the vertical direction. Of the pair of jaw flow paths 43, one jaw flow path 43 arranged in the upper jaw 36a is the upper jaw flow path 43a, and the other jaw flow path 43 arranged in the lower jaw 36b is the lower jaw. The flow path 43b. That is, the jaw flow path 43 is provided in each jaw 36.

As shown in FIGS. 3 to 8, the jaw flow paths 43 have different cross-sectional shapes of the flow paths in each portion of the holder 3 in the axial direction (X-axis direction). The "cross section of the flow path" of the jaw flow path 43 as used herein refers to, for example, a cross section of the flow path appearing in a virtual plane perpendicular to the axial direction of the holder 3. The cross-sectional shape of the jaw flow path 43 gradually changes from the connection portion with the connection flow path 42 toward the tool tip side.

Specifically, the jaw flow path 43 is a vertically long guide flow path portion in which the cross section of the flow path has a larger dimension a in the vertical direction (Z-axis direction) than the dimension b in the tool width direction (Y-axis direction). 44 and the guide flow path portion 44 are communicated with each other, are arranged closer to the insert mounting seat 35 on the tool tip side than the guide flow path portion 44 and in the vertical direction, and open at the end portion of the jaw portion 36 on the tool tip side. The cross section of the flow path has a horizontally long ejection flow path portion 45 in which the dimension b in the tool width direction is larger than the dimension a in the vertical direction.
The cross section of each flow path of the guide flow path portion 44 and the ejection flow path portion 45 has an elliptical shape. In this embodiment, as shown in FIGS. 5A and 5B, the cross section of the flow path at the connection portion between the guide flow path portion 44 and the ejection flow path portion 45 has a circular (substantially perfect circle) shape. The flow path cross-sectional area of the guide flow path portion 44 and the flow path cross-sectional area of the ejection flow path portion 45 are the same as each other, or the ejection flow path portion is larger than the flow path cross-sectional area of the guide flow path portion 44. The flow path cross-sectional area of 45 is small.

As shown in FIGS. 3, 4A, 4B, 7A, and 7B, the guide flow path portions 44 are provided in the pair of jaw flow paths 43, respectively. In the flow path cross section of the guide flow path portion 44, the maximum value of the ratio (a / b) of the vertical dimension a to the dimension b in the tool width direction is 1.2 or more and 5.0 or less. Of the pair of guide flow path portions 44, one guide flow path portion 44 included in the maxillary flow path 43a is the upper guide flow path portion 44a, and the other guide flow path portion 44 included in the lower jaw portion flow path 43b is the lower guide flow path portion 44. The guide flow path portion 44b.

As shown in FIG. 3, the upper guide flow path portion 44a extends downward from the connection portion with the upper connection flow path 42a toward the tool tip side. In the flow path cross section of the upper guide flow path portion 44a, the ratio (a / b) of the vertical dimension a to the dimension b in the tool width direction becomes smaller toward the tool tip side.

The lower guide flow path portion 44b extends upward from the connection portion with the lower connection flow path 42b toward the tool tip side. In the flow path cross section of the lower guide flow path portion 44b, the ratio (a / b) of the vertical dimension a to the dimension b in the tool width direction becomes smaller toward the tool tip side.

As shown in FIGS. 3, 6A, 6B, 8A, and 8B, the ejection flow path portions 45 are provided in the pair of jaw flow paths 43, respectively. In the flow path cross section of the ejection flow path portion 45, the maximum value of the ratio (b / a) of the dimension b in the tool width direction to the dimension a in the vertical direction is 1.2 or more and 5.0 or less. Of the pair of ejection flow paths 45, one ejection flow path 45 provided in the maxillary flow path 43a is the upper ejection flow path portion 45a, and the other ejection flow path portion 45 included in the lower jaw passage 43b is the lower. The ejection flow path portion 45b.

As shown in FIG. 3, the upper ejection flow path portion 45a extends downward from the connection portion with the upper guide flow path portion 44a toward the tool tip side. The cross section of the flow path of the upper ejection flow path portion 45a increases as the ratio (b / a) of the dimension b in the tool width direction to the dimension a in the vertical direction increases toward the tool tip side. The tip of the upper ejection flow path portion 45a opens on the surface of the maxilla portion 36a facing the tip side. The tip end portion, that is, the opening portion (upper ejection port) of the upper ejection flow path portion 45a is arranged adjacent to the upper side of the insert mounting seat 35. The opening of the upper ejection flow path portion 45a opens toward the rake face 22 and the cutting edge 21 of the cutting insert 2.

The lower ejection flow path portion 45b extends upward from the connection portion with the lower guide flow path portion 44b toward the tool tip side. The cross section of the flow path of the lower ejection flow path portion 45b increases as the ratio (b / a) of the dimension b in the tool width direction to the dimension a in the vertical direction increases toward the tool tip side. The tip of the lower ejection flow path portion 45b opens on a surface facing the tip side of the lower jaw portion 36b. The tip end portion, that is, the opening portion (lower ejection port) of the lower ejection flow path portion 45b is arranged adjacent to the lower side of the insert mounting seat 35. The opening of the lower ejection flow path portion 45b opens toward the flank 23 and the cutting edge 21 of the cutting insert 2.

[Action and effect of this embodiment]
According to the grooving tool 1 of the present embodiment described above, even if the jaw portion 36 for clamping the cutting insert 2 is in the shape of a curved plate whose plate thickness becomes thinner as it is separated from the insert mounting seat 35 in the vertical direction. The coolant can be ejected accurately and stably from the jaw flow path 43 extending in the jaw portion 36 toward the vicinity of the cutting edge 21.

Specifically, of the jaw flow path 43, the flow path cross section of the ejection flow path portion 45 that opens at the end of the jaw portion 36 on the tool tip side has a dimension b in the tool width direction larger than the dimension a in the vertical direction. Since it has a horizontally long shape, the ejection flow path portion 45 is arranged in a portion of the jaw portion 36 having a thick plate thickness, that is, a portion close to the insert mounting seat 35, and includes at least a cutting edge portion 21a from the ejection flow path portion 45. The coolant can be stably ejected over a wide range over the entire cutting edge 21.
Further, since the flow path cross section of the guide flow path portion 44 of the jaw portion flow path 43 has a vertically long shape in which the dimension a in the vertical direction is larger than the dimension b in the tool width direction, the guide flow path portion 44 can be used with the jaw. It is possible to arrange the portion 36 in a portion (thin-walled portion) having a thin plate thickness, which is separated from the insert mounting seat 35 in the vertical direction. That is, while the flow path cross-sectional area of the guide flow path portion 44 is largely secured, that is, the flow rate of the coolant ejected from the jaw portion 36 is secured, the guide flow path portion 44 is used as the thin portion of the jaw portion 36. Since it can be arranged, the shape of the flow path from the guide flow path portion 44 to the ejection flow path portion 45 can be easily tilted at an angle in the vertical direction toward the tool tip side. Therefore, it becomes easy to arrange the cutting edge 21 in the vicinity of the extension line of the opening (spouting port) of the ejection flow path portion 45, and the coolant can be accurately and efficiently supplied in the vicinity of the cutting edge 21.

Further, in the present embodiment, a pair of jaw portions 36 are provided on the upper side and the lower side of the insert mounting seat 35, and jaw portion flow paths 43 are provided in each jaw portion 36, respectively.
In this case, of the pair of jaws 36, the maxillary flow path 43 (maxillary flow path 43a) of the maxillary portion 36a arranged above the insert mounting seat 35 is cut through the rake face 22 of the cutting insert 2. Coolant can be ejected near the blade 21. Further, of the pair of jaw portions 36, the jaw passage 43 (lower jaw passage 43b) of the lower jaw portion 36b arranged below the insert mounting seat 35 is cut through the flank surface 23 of the cutting insert 2. Coolant can be ejected near the blade 21. Therefore, the coolant can be more stably supplied to the vicinity of the cutting edge 21.

Further, in the present embodiment, the flow path cross-sectional area of the ejection flow path portion 45 is smaller than the flow path cross-sectional area of the guide flow path portion 44, or the flow path cross-sectional area of the guide flow path portion 44 and the ejection flow. The flow path cross-sectional areas of the road portions 45 are the same as each other.
For example, unlike the present embodiment, if the flow path cross-sectional area of the ejection flow path portion 45 is larger than the flow path cross-sectional area of the guidance flow path portion 44, when the coolant flows from the guide flow path portion 44 into the ejection flow path portion 45. In addition, the flow velocity may decrease or pressure loss may occur due to the increase in the cross-sectional area of the flow path.
On the other hand, according to the present embodiment, when the coolant flows from the guide flow path portion 44 into the ejection flow path portion 45, a decrease in the flow velocity, a pressure loss, and the like can be suppressed. The flow velocity of the coolant flowing through the ejection flow path portion 45 is stably increased, and the vicinity of the cutting edge 21 can be efficiently cooled by the coolant ejected from the ejection flow path portion 45.

Further, in the present embodiment, in the flow path cross section of the guide flow path portion 44, the ratio (a / b) of the dimension a in the vertical direction to the dimension b in the tool width direction is 1.2 or more and 5.0 or less.
When the ratio (a / b) is 1.2 or more, the flow path cross section of the guide flow path portion 44 becomes stable and vertically elongated, and the guide flow path portion 44 is arranged in the thin-walled portion of the jaw portion 36. Cheap. Therefore, the above-mentioned action and effect of the present embodiment can be obtained more stably. When the ratio (a / b) is 5.0 or less, it is possible to suppress problems such as an increase in pressure loss due to the shape of the cross section of the flow path being too flat in the vertical direction.

Further, in the present embodiment, in the flow path cross section of the ejection flow path portion 45, the ratio (b / a) of the dimension b in the tool width direction to the dimension a in the vertical direction is 1.2 or more and 5.0 or less.
When the ratio (b / a) is 1.2 or more, the cross section of the flow path of the ejection flow path portion 45 becomes stable and horizontally long, and the coolant is stabilized over the entire cutting edge 21 from the ejection flow path portion 45. Easy to spout. Therefore, the above-mentioned action and effect of the present embodiment can be obtained more stably. When the ratio (b / a) is 5.0 or less, the shape of the cross section of the flow path is too flat in the horizontal direction, and the coolant is ejected in the form of mist. It is possible to suppress problems that are unnecessarily dissipated.

[Other configurations included in the present invention]
The present invention is not limited to the above-described embodiment, and the configuration can be changed without departing from the spirit of the present invention, for example, as described below.

In the above-described embodiment, the cross section of each flow path of the guide flow path portion 44 and the ejection flow path portion 45 has an elliptical shape, but the present invention is not limited to this.
9 to 13 show a modification of the head member 32 of the grooving tool 1 described in the above-described embodiment. In this modification, the cross section of each flow path of the guide flow path portion 44 and the ejection flow path portion 45 has a polygonal shape. In the illustrated example, the cross section of each flow path of the guide flow path portion 44 and the ejection flow path portion 45 is triangular. In addition to the triangular shape, it may have a quadrangular shape (diamond shape), a pentagonal shape, a hexagonal shape, or the like. In this modification, as shown in FIGS. 12A and 12B, the cross section of the flow path at the connection portion between the guide flow path portion 44 and the ejection flow path portion 45 has a regular triangular shape.

As shown in FIGS. 11A and 11B, the flow path cross section of the guide flow path portion 44 has a ratio (a / b) of the dimension a in the vertical direction to the dimension b in the tool width direction of 1.2 or more and 5.0 or less. Is.
As shown in FIGS. 13A and 13B, the flow path cross section of the ejection flow path portion 45 has a ratio (b / a) of the dimension b in the tool width direction to the dimension a in the vertical direction of 1.2 or more and 5.0 or less. Is.
As shown in FIG. 10, the shape of the flow path cross section perpendicular to the tool width direction of the connection flow path 42 is a polygonal shape, specifically a triangular shape.
Also in this modification, the same action and effect as those of the above-described embodiment can be obtained. As shown in this modification, only one set of the connection flow path 42 and the jaw flow path 43 of the coolant flow path 4 may be provided in the head member 32.

Further, in the above-described embodiment, the upper jaw portion 36a is curved so as to be located on the right side (+ Y side) toward the upper side (+ Z side) from the insert mounting seat 35 when viewed from the tool tip side, and the lower jaw portion 36b is formed. , However, the example is given in which the insert mounting seat 35 is curved so as to be located on the right side toward the lower side (-Z side), but the present invention is not limited to this.
Although not particularly shown, the upper jaw portion 36a is curved so as to be located on the left side (-Y side) from the insert mounting seat 35 toward the upper side when viewed from the tool tip side, and the lower jaw portion 36b is curved from the insert mounting seat 35. It may be curved so as to be located on the left side toward the lower side.

Further, in the above-described embodiment, a pair of jaw portions 36 having a jaw portion flow path are provided on the upper side and the lower side of the insert mounting seat 35, but the present invention is not limited to this. Only one jaw portion having a jaw passage may be provided on the upper side or the lower side of the insert mounting seat 35. In this case, the cutting insert 2 is clamped between the jaw portion having no jaw flow path and the jaw portion having the jaw flow path, and is fixed to the insert mounting seat.
Although not shown, the jaw portion having no jaw passage may be formed separately from the head member 32. In this case, the jaw portion having no jaw flow path is configured by a clamping member capable of approaching the jaw portion having the jaw flow path and clamping the cutting insert 2 by sliding movement or the like.

The present invention may be combined with each of the configurations described in the above-described embodiments and modifications, and the configurations can be added, omitted, replaced, or otherwise changed without departing from the spirit of the present invention. .. Further, the present invention is not limited to the above-described embodiments and the like, but is limited only to the scope of claims.

According to the grooving tool of the present invention, the coolant can be accurately ejected in the vicinity of the cutting edge while ensuring the coolant flow rate. Therefore, it has industrial applicability.

1 ... Grooving tool 2 ... Cutting insert 3 ... Holder 4 ... Coolant flow path 21 ... Cutting edge 21a ... Front blade (cutting edge)
35 ... Insert mounting seat 36 ... Jaw 43 ... Jaw flow path 44 ... Guide flow path 45 ... Ejection flow path a ... Vertical dimension of flow path cross section b ... Tool width direction dimension of flow path cross section

Claims (8)

Cutting inserts with cutting edges and
A holder that holds the cutting insert and
A coolant flow path extending inside the holder is provided.
The cutting edge has a cutting edge portion extending in the tool width direction.
The holder is
The insert mounting seat on which the cutting insert is placed and
It has a pair of jaws that are located above and below the insert mounting seat and come into vertical contact with the cutting insert.
At least one of the jaws has a plate shape extending in the direction perpendicular to the tool width direction and has a curved shape when viewed from the tool tip side, and the plate thickness increases as the distance from the insert mounting seat increases or decreases. Thinn,
The coolant flow path has a jaw flow path that extends inside the at least one jaw portion.
The jaw flow path is
Guidance flow path and
A jet flow that communicates with the guide flow path portion, is arranged closer to the insert mounting seat on the tool tip side than the guide flow path portion and in the vertical direction, and opens at the end portion of the jaw portion on the tool tip side. Has a road part,
The cross section of the flow path of the guide flow path portion has a vertically long shape in which the dimension in the vertical direction is larger than the dimension in the tool width direction.
A grooving tool in which the cross section of the flow path of the ejection flow path portion has a horizontally long shape in which the dimension in the tool width direction is larger than the dimension in the vertical direction. The jaw flow path is provided in each of the jaws.
The grooving tool according to claim 1. The flow path cross-sectional area of the ejection flow path portion is smaller than the flow path cross-sectional area of the guide flow path portion.
The grooving tool according to claim 1 or 2. The flow path cross-sectional area of the guide flow path portion and the flow path cross-sectional area of the ejection flow path portion are the same as each other.
The grooving tool according to claim 1 or 2. The maximum value of the ratio a / b of the vertical dimension a to the dimension b in the tool width direction in the flow path cross section of the guide flow path portion is 1.2 or more and 5.0 or less, and the guide flow path is described. The ratio a / b of the portion becomes smaller toward the tool tip side.
The grooving tool according to any one of claims 1 to 4. In the flow path cross section of the ejection flow path portion, the maximum value of the ratio b / a of the dimension b in the tool width direction to the dimension a in the vertical direction is 1.2 or more and 5.0 or less, and the ejection flow path is described. The ratio b / a of the portion increases toward the tool tip side.
The grooving tool according to any one of claims 1 to 5. The cross section of each flow path of the guide flow path portion and the ejection flow path portion has an elliptical shape.
The grooving tool according to any one of claims 1 to 6. The cross section of each flow path of the guide flow path portion and the ejection flow path portion is polygonal.
The grooving tool according to any one of claims 1 to 6.

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