Shank and cutting tool having a shank

Abstract

Even when a cutting insert having a long length is used, the effects of bending of the tool head and increase in the moment acting on the fastening mechanism can be suppressed, and thus better cutting performance can be achieved. A tool head replacement type cutting tool (1) includes a shank (10) including a fastening mechanism (30) formed at a front end portion (10t) in a length direction of the shank (10) and configured to mount a tool head (20), and a recess (16) formed at the front end portion (10t) and configured to accommodate a portion of a cutting insert (50) held by the tool head (20) to avoid interference with the cutting insert (50). The recess (16) can be configured to accommodate a non-use portion of the cutting insert (50) held by the tool head (20) to avoid interference with the cutting insert in a state where the tool head (20) is mounted at the front end portion (10t).

Description

TECHNICAL FIELD

[0001] The present application relates to a shank and a cutting tool having the same. BACKGROUND

[0002] With regard to a tool bit replaceable cutting tool in which a tool bit that holds a blade is detachably fastened to the front end portion of a shank, there are proposed technologies related to a structure for detaching the tool bit in a state in which the shank is installed in a machine tool such as a tool holder, and technologies related to a fastening mechanism of the tool bit and the shank, and the like. Further, in the related art, with regard to the tool bit replaceable cutting tool, there are proposed technologies conceived from the viewpoint of improving workability by enabling quick replacement of a cutting insert, and achieving cost reduction by shortening a preparatory time by measuring a blade position in a state of being detached from a machine tool (for example, refer to Patent Documents 1 to 4).

[0003] Further, in use of the cutting tool, there are cases in which a long cutting insert is required, and there are proposed technologies related to a structure for holding such a cutting insert (refer to Patent Documents 5 and 6).

[0004] Prior Art Documents

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: Japanese Patent Publication No. 2020-28943

[0007] Patent Document 2: International Patent Laid-Open No. 2020-533188

[0008] Patent Document 3: International Patent Laid-Open No. 2014-524357

[0009] Patent Document 4: International Patent Laid-Open No. 2012-522651

[0010] Patent Document 5: Japanese Patent Publication No. 2007-203379

[0011] Patent Document 6: Japanese Patent Publication No. H06-155110

[0012] Technical Problem

[0013] However, in the existing tool bit replacement type cutting tool, no consideration is given to fastening a cutting insert whose overall length is longer than the difference between the overall length of the tool bit and the length of the fastening mechanism (a tool bit attachment / detachment pin for attaching / detaching the tool bit to / from the shank) in the length direction of the shank (hereinafter referred to as "the amount by which the tool bit protrudes from the shank"). Generally, in a small cutting tool or the like having a small width, if the fastening mechanism cannot be displaced in a direction away from the insert, the insert and the fastening mechanism interfere with each other. In this regard, in the related art, as a method for separating the fastening mechanism and the cutting insert without interfering with each other, there is no choice but to increase the effective length of the tool bit. In other words, as described above, in the case of using a cutting insert whose overall length is long, in the existing cutting tool, there is no choice but to set the amount by which the tool bit protrudes from the shank to be longer than the overall length of the cutting insert. However, in the existing tool bit replacement type cutting tool, only the shank abuts against the tool holder, and only the fastening mechanism receives the force applied to the tool bit, so if the amount by which the tool bit protrudes from the shank is increased, the distance between the cutting machining point and the fastening mechanism becomes longer, and the force applied to the fastening mechanism affects the cutting performance, thereby causing a serious adverse effect on the cutting performance.

[0014] Therefore, an object of the present application is to provide a shank and a cutting tool having the shank, which can suppress the effects caused by the bending of the tool bit and the increase in the moment applied to the fastening mechanism, or the like, even in the case of using a cutting insert whose overall length is long, thereby achieving better cutting performance. SUMMARY

[0015] One embodiment of the present application provides a shank, which is a shank of a tool bit replacement type cutting tool, the shank including: a fastening mechanism formed at a front end portion in the length direction of the shank, for mounting a tool bit; and a recess formed at the front end portion, which accommodates a portion of a cutting insert held in the tool bit, to avoid interference with the cutting insert.

[0016] According to the holder as described above, it is possible to mount a tool bit on the holder, in which a cutting insert is mounted on the tool bit so that the tool bit protrudes from the holder by an amount longer than the full length of the cutting insert. That is, in the related art, a portion of the cutting edge of the cutting insert held by the tool bit described above interferes with the fastening mechanism or the holder, and in view of this, according to the holder of the present embodiment, the interference is avoided by housing a portion of the cutting insert in the recess. Therefore, in the related art, the amount by which the tool bit protrudes from the holder is set to be longer than the full length of the cutting insert, and in view of this, according to the present embodiment, the tool bit can be mounted on the holder without the above-described setting. As a result, the tool bit can be mounted on the holder without increasing the amount by which the tool bit protrudes from the holder, which means that the distance between the cutting point and the fastening mechanism does not need to be increased, and therefore, even when a cutting insert having a long full length is used, the effects of the increase in the bending of the tool bit and the moment acting on the fastening mechanism, and the like can be suppressed.

[0017] In the holder as described above, the holder has a substantially rectangular parallelepiped shape in which a cross section perpendicular to the length direction of the holder is rectangular, the fastening mechanism formed at the front end portion in the length direction of the holder is a mechanism for attaching and detaching the tool bit, and has an attachment and detachment operation portion through which the attachment and detachment operation of the tool bit can be performed from a direction substantially perpendicular to the length direction, and the recess can be provided in a shape in which it is recessed from a first reference surface by a step difference on the first reference surface, the first reference surface being a surface of the side surface of the holder on the opposite side of the operation surface on which the attachment and detachment operation portion is located, and the value of the step difference is set to be smaller than the width of the first reference surface and larger than 10% of the width of the first reference surface.

[0018] In the holder as described above, the recess can also be provided so as to house a non-use portion of the cutting insert held by the tool bit in a state in which the tool bit is attached to the front end portion so as to avoid interference with the cutting insert.

[0019] In the holder as described above, in the side surface of the holder, the surface on the side of the operation surface can have a stepped shape, and the step portion forming the stepped shape can be provided so as to be closer to the distal end portion than the step portion formed between the first reference surface and the recess along the length direction.

[0020] In the holder as described above, the operation surface can be a flat surface that extends continuously along the entire length of the holder.

[0021] The holder as described above can be provided so that the interval between the operation surface and the first reference surface is larger than the width of the first reference surface.

[0022] In the holder as described above, the hole for attachment and detachment of the tool bit of the fastening mechanism for attaching and detaching the tool bit can be offset in a direction away from the recess, compared to the central axis of the holder extending along the length direction.

[0023] In the tool shank described above, the recess can be formed with a stopper.

[0024] In the tool shank described above, the stopper can be formed on one side of the recess in the width direction of the first reference surface.

[0025] In the tool shank described above, the stopper can be formed on both sides of the recess in the width direction of the first reference surface.

[0026] One embodiment of the present application provides a cutting tool including the tool shank described above. BRIEF DESCRIPTION OF DRAWINGS

[0027] Fig. 1 FIG. 1 is a perspective view of a tool holder in which a cutting tool is installed in one embodiment of the present application.

[0028] Fig. 2 FIG. 2 is a perspective view of the tool holder shown in FIG. 1, viewed from another angle.

[0029] Fig. 3 FIG. 3 is a perspective view of the cutting tool, in which a tool head is separated from a tool shank.

[0030] Fig. 4 FIG. 4 is a perspective view of the cutting tool, in which the tool head is installed in the tool shank.

[0031] Fig. 5 FIG. 5 is a perspective view of the cutting tool, in which a cutting insert is detached from the tool head shown in FIG. 3. Fig. 4

[0032] FIG. 6 is a perspective view of the cutting tool, in which the cutting insert is detached from the tool head shown in FIG. 3. Fig. 6A Fig. 3 FIG. 7 is a view of the tool shank, viewed from the A direction in FIG. 1.

[0033] Fig. 6B Fig. 3 FIG. 8 is a view of the tool shank, viewed from the B direction in FIG. 1.

[0034] Fig. 6C FIG. 9 is a view of the tool shank, viewed from the C direction in FIG. 1. Fig. 3

[0035] Fig. 7 FIG. 10 is an enlarged perspective view of a front end portion of the tool shank and the tool head separated from the front end portion of the tool shank.

[0036] Fig. 8 FIG. 11 is a schematic view of the front end portion of the tool shank, viewed from the A direction in FIG. 1. Fig. 3

[0037] FIG. 12 is a schematic view of the front end portion of the tool shank, in which the tool head is installed in the tool shank shown in FIG. 1. Fig. 9 Fig. 8

[0038] Fig. 10 ​​​​​A perspective view of a shape example of the recess of the front end portion of the shank.

[0039] Fig. 11 A perspective view of another shape example of the recess of the front end portion of the shank.

[0040] Fig. 12 A perspective view of still another shape example of the recess of the front end portion of the shank.

[0041] Fig. 13 A perspective view of the state in which the head is mounted to Fig. 7 A perspective view of the state of the front end portion of the shank shown.

[0042] Fig. 14 A perspective view of the existing cutting tool as a comparative example. Fig. 13 A perspective view of the existing cutting tool as a comparative example.

[0043] Explanation of Main Element Reference Numerals

[0044] Cutting tool 1

[0045] Shank 10

[0046] Tip portion 10b

[0047] Gripped portion 10h

[0048] Front end portion 10t

[0049] Center axis 10X of the shank

[0050] First reference surface (side surface) 11

[0051] Step portion 11D (formed between the first reference surface and the recess)

[0052] Second reference surface (side surface) 12

[0053] Third side surface (side surface) 13

[0054] Screw hole 13b

[0055] Step portion 13D (of the surface on which the operation surface is located among the side surfaces)

[0056] Operation surface (side surface) 13S

[0057] Fourth surface (side surface) 14

[0058] Mounting portion 15

[0059] Protrusion 15t

[0060] Recess 16

[0061] Rim 18 (provided in the recess)

[0062] tool bit 20

[0063] knock pin 21

[0064] insert seat 22

[0065] restraining portion 23

[0066] fastening mechanism 30

[0067] tool bit knock pin hole 31

[0068] knock operation portion 32

[0069] set screw 40

[0070] cutting insert 50

[0071] cutting edge 52

[0072] mounting screw 54

[0073] tool holder 200

[0074] stepped difference of the step portion 11D of the first reference surface

[0075] amount by which the tool bit protrudes from the shank HE

[0076] overall length of the insert LC

[0077] overall length of the tool bit LH

[0078] length of the knock pin LP

[0079] height of the shank (width of the first reference surface) SH

[0080] width of the shank (spacing between the operation surface and the first reference surface) SW DETAILED DESCRIPTION

[0081] Hereinafter, a preferred embodiment of the shank 10 and a tool bit replaceable cutting tool (hereinafter, sometimes referred to simply as a cutting tool) 1 having the shank 10 according to the present application will be described in detail with reference to the accompanying drawings (see FIGS. 1 to 6). Fig. 1 and the like).

[0082] [1st Embodiment]

[0083] The tool bit replaceable cutting tool 1 is configured to cut into a workpiece (omitted from the drawing) by feeding the cutting edge 52 of the cutting insert 50 when machining is performed with an automatic lathe (omitted from the drawing) or the like. In the automatic lathe that automatically performs lathe machining, the long workpiece is fed in a predetermined direction (Z-axis direction in the present embodiment) while the cutting tool 1 is moved in a direction perpendicular to the Z-axis direction (in the present embodiment, for convenience, the axis perpendicular to the Z-axis is referred to as the X-axis), thereby turning the workpiece and cutting out a three-dimensional shape (refer to Fig. 1 , Fig. 2 ). In some cases, a plurality of tool bit replaceable cutting tools 1 are arranged in a "turret" on the tool holder 200, and the tool holder 200 is moved in the X-axis direction or in the Y-axis direction perpendicular to both the X-axis direction and the Z-axis direction according to the turning machining method, and the cutting insert 50 is appropriately selected while being moved and replaced, thereby performing the intended machining (refer to Fig. 1 , Fig. 2 ).

[0084] The cutting tool 1 of the present embodiment for such turning machining is a tool bit replaceable cutting tool in which the tool bit 20 is detachably attached to the shank 10, and includes the shank 10, the tool bit 20, and a fastening mechanism 30 for attaching the tool bit 20 to the shank 10 (refer to Fig. 7 and the like).

[0085] The shank 10 is formed so as to be attached to the tool holder 200 in a state in which the holding portion (the main body portion whose cross section is constant in the shank 10 of the present embodiment) 10h thereof is held (refer to Figs. 1-3 and the like). As one example, the shank 10 of the present embodiment is a substantially rectangular parallelepiped shape whose cross section is rectangular, and the cross section is perpendicular to the length direction (direction coinciding with the above-described X-axis direction) along the central axis 10X of the shank 10 (refer to Fig. 6B and the like). Figs. 6A-6C

[0086] In the present embodiment, for convenience of explanation, four side surfaces of the shank 10 are defined as follows. First, a surface viewed in the direction indicated by the reference sign B in Fig. 3 is set as a "first reference surface", and is indicated by the reference sign 11 (refer to Fig. 3 , Fig. 6B and the like). The first reference surface 11 functions as a reference surface (mounting surface) for positioning in the Z direction when the shank 10 is attached to the tool holder 200 (refer to Fig. 1 , Fig. 2 and the like). The width of the first reference surface 11 (also referred to as the height of the shank) is indicated by the reference sign SH (refer to Fig. 3 , Fig. 6B and the like). In addition, a surface viewed in the direction indicated by the reference sign C in Fig. 3 ​The plane viewed from the direction indicated by label A is designated as "plane number 4" and denoted by label 14 (see reference). Figs. 3-6B (etc.). The surface opposite to the fourth surface 14 is designated as the "second reference surface", denoted by the number 12 (see reference). Fig. 6B (etc.). When the tool holder 10 is mounted to the tool post 200, the second reference surface 12 functions as a reference surface (mounting surface) for positioning in the Y direction (see reference). Fig. 1 , Fig. 2 Furthermore, the side opposite to the first reference surface 11 is designated as the "third side surface" and denoted by the reference numeral 13. Also, when the third side surface 13 has a stepped portion 13D, the surface in the third side surface 13 with a screw hole 13b for fixing the screw 40 is specifically called the "operating surface" and denoted by the reference numeral 13S (see reference). Fig. 6A (etc.). On the operating surface 13S, the fixing screw 40 can be rotated from this side of the operating surface 13S to load or unload the cutter head 20 (see reference). Fig. 8 , Fig. 9 The screw hole 13b forms part of the loading and unloading operation section 32 of the fastening mechanism 30 for loading and unloading the cutter head 20 relative to the tool holder 10.

[0087] The front end 10t of the tool holder 10 has a mounting portion 15 and a recess 16 (see reference). Fig. 3 (etc.). The mounting part 15 is the part that mounts the cutter head 20 using the fastening mechanism 30. The mounting part 15 is provided with a cutter head loading / unloading hole 31 into which the loading / unloading pin 21 of the cutter head 20 can be inserted (see reference). Fig. 3 (etc.). Additionally, the mounting portion 15 is provided with a protrusion 15t, which uniquely defines the orientation of the cutter head 20 by embedding it into a predetermined recess (not shown) in the mounted state (see reference). Fig. 3 , Fig. 6A wait).

[0088] A recess 16 is formed at the front end 10t of the tool holder 10 to accommodate a portion of the cutting blade 50 held in the tool head 20, so as to avoid interference with the cutting blade 50 (see reference). Fig. 4 (etc.). For example, in the tool head replaceable cutting tool 1 of this embodiment, the recess 16 is configured to accommodate the non-use portion (including the side of the cutting edge 52 not used for cutting) of the cutting blade 50 held on the tool head 20 when the tool head 20 is mounted on the front end 10t of the tool holder 10, in order to avoid interference with the cutting blade (see reference). Fig. 4 , Fig. 9 (etc.). In this embodiment, the recess 16 is formed by cutting off a portion of one side of the first reference surface 11 of the handle 10 to create a stepped portion 11D (in Fig. 6A In the middle, the step difference of step section 11D is indicated by the symbol DH) and is formed (refer to)Fig. 6A ). The shape of the recess 16 and the step difference DH of the stepped portion 11D are not particularly limited, and in the present embodiment, the recess 16 is formed in a shape that is recessed from the first reference surface 11 by the step difference DH, and the value of the step difference DH is smaller than the width (height of the shank) SH of the first reference surface 11 and greater than 10% of the width (height of the shank) SH of the first reference surface 11 (see Fig. 6A , etc.). That is, the size (depth) of the step difference DH is appropriately set in consideration of the fact that it is preferable to be able to accommodate the entire width of the cutting insert 50, but if it is equal to or less than 10%, there is a possibility that only a part of the width of the cutting insert 50 can be accommodated, and on the other hand, if the value of DH is too large, from the viewpoint of the purpose of accommodating the cutting insert 50, the value being too large can cause a decrease in the rigidity of the shank 10.

[0089] In addition, as described above, the shank 10 is stepped (see Fig. 6A , etc.) in that the stepped portion 13D is provided on the third side surface 13. The position of the stepped portion 13D in the longitudinal direction of the shank 10 (in the direction along the central axis 10X) is not particularly limited, and as one example, in the present embodiment, the stepped portion 13D is provided closer to the tip end portion 10t than the stepped portion 11D formed between the first reference surface 11 and the recess 16 in the longitudinal direction (see Fig. 6A , etc.). From the second reference surface 12 or the fourth surface 14, the shank 10 of the present embodiment is formed in a crank shape near the tip end portion 10t (see Fig. 6A , etc.), and the stepped portion 13D is provided at the above position so that the intermediate width of the crank-shaped portion does not become extremely narrow, and thus it is possible to provide the vicinity of the tip end portion 10t in a predetermined crank shape while ensuring the rigidity required of the shank 10.

[0090] The tool head 20 is an element that is detachably attached to the tip end portion 10t of the shank 10. The tool head 20 of the present embodiment is configured to include a detachment pin 21, an insert mounting seat 22, a suppression portion 23, and the like (see Fig. 7 , etc.). The detachment pin 21 is a pin that is insertable into the tool head detachment hole 31 of the shank 10, and has a length LP (see Fig. 9 ) that is pressed by the fixing screw 40 to be fixed in a state in which it is inserted into the tool head detachment hole 31. The insert mounting seat 22 is a seat for mounting the cutting insert 50 by means of the attachment screw 54, and in the tool head 20, is provided on the side surface toward the first reference surface 11 of the shank 10 (see Fig. 7 , Fig. 9 , etc.). The cutting insert 50 having a pair of cutting edges 52 can be mounted on this insert mounting seat 22. The suppression portion 23 is provided in the vicinity of the insert mounting seat 22 to control the cutting insert 50 (see Fig. 7The amount HE by which the insert 20 protrudes from the shank 10 is the length in the axial direction from the front end face of the mounting portion 15 of the shank 10 to the front end portion of the suppression portion 23, in other words, the length obtained by subtracting the length LP of the attachment / detachment pin 21 from the overall length LH of the insert 20 (HE = LH - LP) (see FIG. 2). Further, since the cutting insert 50 can be replaced with various types, the description here is made with respect to the insert 20. Fig. 9 Further, since the cutting insert 50 can be replaced with various types, the description here is made with respect to the insert 20.

[0091] The fastening mechanism 30 is a mechanism for mounting the insert 20 at the front end portion 10t of the shank 10, and is constituted by the attachment / detachment pin 21 of the insert 20, the insert attachment / detachment hole 31, the attachment / detachment operation portion 32, and the like. In order to enable the attachment / detachment pin 21 of the insert 20 to be inserted, the insert attachment / detachment hole 31 is provided on the mounting portion 15 of the front end portion 10t of the shank 10 (see FIG. 2). Fig. 3 The attachment / detachment operation portion 32 is a portion that is operated when the insert 20 is attached and detached, and is constituted by the screw hole 13b and the fixing screw 40 screwed into the screw hole 13b (see FIG. 2). Fig. 7 In the insert-replaceable cutting tool 1 of the present embodiment, the insert 20 can be attached and detached by the operation of tightening or detaching the fixing screw 40 from a direction that is substantially perpendicular to the length direction of the shank 10 (the direction of the center axis 10X). Further, the position of the insert attachment / detachment hole 31 is not particularly limited, and can be provided at a position that coincides with the center axis 10X of the shank 10, or at a position that deviates from the center axis 10X of the shank 10. In the present embodiment, the insert attachment / detachment hole 31 is provided at a position that deviates from the center axis 10X in the direction away from the recessed portion 16 (in other words, in the direction close to the operation face 13S) (see FIG. 2). Fig. 8 In this way, in the case where the insert attachment / detachment hole 31 is offset, since a surplus wall is generated in the portion of the front end portion 10t of the shank 10 that is close to the recessed portion 16, it is easy to avoid the phenomenon of the thin-walled portion being generated due to the formation of the recessed portion 16.

[0092] As described above, the insert-replaceable cutting tool 1 can be used as a structure (assembly) constituted by the shank 10, the insert 20, and the fastening mechanism 30 for mounting the insert 20 at the shank 10. In actual use, the shank 10 is fixed to the tool holder 200 of the turret type or the like by the fixing member, the insert 20 is fixed to the shank 10 by the fastening mechanism 30, the cutting insert 50 is mounted to the insert seating portion 22 of the insert 20, and in this state, the cutting edge 52 is embedded in the rotating workpiece (workpiece material) to perform cutting processing (see FIG. 1). Fig. 1 , Fig. 2

[0093] ​According to the interchangeable cutting tool 1 or the tool holder 10 constituting the interchangeable cutting tool 1, even when using the entire length of the cutting insert (as in this embodiment, if it is a cutting insert 50 having a pair of cutting edges 52, the total length of the cutting insert refers to the length along the central axis 10X of the tool holder 10 from the tip of one cutting edge 52 to the tip of the other cutting edge 52), Fig. 9 When using a longer cutting insert 50 (represented by the numeral LC), the effects of bending of the cutting head 20 and increased torque acting on the fastening mechanism 30 can be suppressed, thereby achieving better cutting performance. For example, when using a cutting insert 50 with a total insert length LC, if the total length of the cutting head is simply increased in accordance with the total insert length as in the prior art, and a recess for accommodating the non-used portion of the cutting edge is provided on the cutting head, the amount of the cutting head protruding from the tool holder will increase. Consequently, the length from the fastening mechanism to the cutting point (cutting edge 52) will also increase, leading to bending of the cutting head and increased torque acting on the fastening mechanism, which may affect cutting performance (see reference). Fig. 14 .in, Fig. 14 (The corresponding part of the label is indicated by adding a left-falling stroke (')). In view of this, the tool head replaceable cutting tool 1 or its tool holder 10 according to this embodiment has a structure in which the recess 16 is provided on the tool holder 10 instead of on the tool head 20. Therefore, the recess 16 can accommodate a part of the cutting blade 50 and avoid interference. Therefore, in the prior art, the amount by which the tool head protrudes from the tool holder in the length direction of the tool holder is set to be longer than the full length of the cutting blade. In view of this, according to this embodiment, the tool head 20 can be mounted on the tool holder 10 even without this setting. In other words, the tool head 20 can be mounted on the tool holder 10 without increasing the amount HE of the tool head 20 protruding from the tool holder 10 in the length direction of the tool holder. Since there is no need to increase the distance between the cutting point and the fastening mechanism 30, even if a longer cutting blade 50 is used, the effects of bending of the tool head 20 and the increase of torque acting on the fastening mechanism 30 can be suppressed. If the bending of the cutting head 20 and the load on the fastening mechanism 30 are reduced, the rigidity and other related properties of the cutting head replacement type 1 can be made close to the performance of an integral type (non-cutting head replacement type, which is composed of the same metal parts with cutting blade fastening parts) cutting tool.

[0094] [Second Implementation]

[0095] In the tool head replacement type cutting tool 1 of this embodiment, the operating surface 13S of the tool holder 10 is formed as a plane that extends continuously through the entire length of the tool holder 10, and the entire operating surface 13S formed by the plane constitutes the third side surface 13 (see reference). Fig. 5 , Fig. 6AIn other words, the shank 10 of the present embodiment has a shape in which the stepped portion (13D) is not provided on the third side surface. In addition, in the shank 10 of the present embodiment, the interval (also referred to as the width of the shank) SW between the operation surface 13S (the third side surface 13) and the first reference surface 11 is larger than the width (the height of the shank) SH of the first reference surface 11 (refer to Fig. 6A 、 Fig. 6B ). By providing the third side surface 13 as a flat surface as described above, the cross-sectional area of the shank 10 is increased, thereby improving the rigidity. In addition, by providing the third side surface 13 as a flat surface as described above, it is possible to consider that the third side surface 13 is used instead of the first reference surface 11 as a reference surface for positioning in the Z-axis direction (refer to Fig. 1 、 Fig. 2 ).

[0096]

Third Embodiment

[0097] The recess 16 of the shank 10 in the tool bit replacement type cutting tool 1 can adopt various shapes and forms according to the blade shape (the shape of the cutting edge 52) of the cutting blade 50. Hereinafter, as another embodiment of the recess 16, the recess 16 in which the retaining wall 18 is formed will be described as the third embodiment (refer to Figs. 10-12 ).

[0098] The retaining wall 18 can be formed in the recess 16 with the condition that the non-use side cutting edge 52 of the cutting blade 50 does not interfere. The retaining wall 18 can be formed on both sides in the width direction of the first reference surface 11 (in other words, in the direction of the height SH of the shank, which coincides with the Y-axis direction when the shank 10 is mounted in the tool holder 200) (refer to Fig. 10 ), or can be formed on only one side of the both sides (refer to Fig. 11 、 Fig. 12 ).

[0099] In addition, the above-described embodiments are one preferred embodiment of the present application, but the present application is not limited thereto, and various modifications can be made within the scope of the gist of the present application.

[0100] Industrial Applicability

[0101] The present application is applicable to a shank for a cutting tool or a tool bit replacement type cutting tool having a shank.

Claims

1. A tool holder, wherein the tool holder is a tool holder for a tool with interchangeable cutting tips, the tool holder comprising: A fastening mechanism, formed at the front end of the tool holder along its length, is used to mount the tool head; A recess, formed at the front end, accommodates a portion of the cutting blade held in the cutter head to avoid interference with the cutting blade; The handle is approximately rectangular in shape with a rectangular cross-section, and the cross-section is perpendicular to the length of the handle. The fastening mechanism formed at the front end of the tool holder along its length is a mechanism for attaching and detaching the tool head, and has an attachment / removal operation section that allows the tool head to be attached or detached in a direction substantially perpendicular to the length direction. The recess is configured to be recessed from the first reference surface with a step difference. The first reference surface is the side of the tool holder located on the opposite side of the operating surface where the loading and unloading operation part is located. The value of the step difference is set to be less than the width of the first reference surface and greater than 10% of the width of the first reference surface.

2. The knife handle according to claim 1, wherein, The recess is configured to accommodate the unused portion of the cutting blade held in the cutting head when the cutting head is mounted on the front end to avoid interference with the cutting blade.

3. The knife handle according to claim 2, wherein, On the side of the tool holder, the shape of the side where the operating surface is located is stepped, and the stepped portion forming the stepped portion is set to be closer to the end portion along the length direction than the stepped portion formed between the first reference surface and the recess.

4. The knife handle according to claim 1, wherein, The operating surface is a plane that extends continuously along the entire length of the tool holder.

5. The knife holder according to claim 4, wherein, The interval between the operating surface and the first reference surface is greater than the width of the first reference surface.

6. The knife handle according to claim 1, wherein, Compared to the central axis of the tool holder extending along the length direction, the tool head mounting and dismounting hole of the fastening mechanism for mounting and dismounting the tool head is offset away from the recess.

7. The knife handle according to claim 1, wherein, The recess is formed with a retaining edge.

8. The knife handle according to claim 7, wherein, The retaining edge is formed on one side of the first reference surface of the recess in the width direction.

9. The knife handle according to claim 7, wherein, The retaining edge is formed on both sides of the first reference surface of the recess in the width direction.

10. A cutting tool comprising a tool holder according to any one of claims 1-9.

Images