JP2018079543A - Tool holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool holder capable of enhancing the efficacy in cooling a tool.SOLUTION: A tool insertion space is formed of: a sleeve interior space 320 formed of a sleeve inner peripheral surface 310 of a sleeve 300; and a cover interior space 420 formed of a cover inner peripheral surface 410 of a cover 400. In a cover tip surface 400a of the cover 400, there are formed jets 471a, 472a for jetting cooling medium, the jets being provided radially outside of an opening 420a. The cover 400 includes jetting paths 471, 472 that are in communication with the jets 471a, 472a respectively, and which are tilted axially. In the sleeve inner peripheral surface 310, there are formed grooves 361, 362 extending axially. There is formed a recess 490 connecting axially front end portions of the grooves 361, 362, and axially rear end portions of the jetting paths 471, 472. The recess 490 acts as a connection path connecting the grooves 361, 362 to the jetting paths 471, 472 respectively.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a tool holder for holding a tool, and more particularly to a tool holder having a cooling function for cooling a tool held by the tool holder.

As a tool holder having a cooling function for cooling a tool, for example, a tool holder disclosed in Patent Document 1 is known.
The tool holder disclosed by patent document 1 is provided with the sleeve arrange | positioned at the inner peripheral side of the main-body part and a main-body part. A tool insertion space into which a tool (specifically, a tool shank portion) is inserted is formed by the sleeve inner peripheral surface of the sleeve. The tool inserted into the tool insertion space is clamped by a portion of the sleeve inner peripheral surface corresponding to the elastically deformable gripping portion. In addition, the main body portion is formed with a cooling medium supply path that has an injection port that opens at a distal end surface on the distal end side along the axial direction and is inclined along the axial direction. The cooling medium is injected from the injection port through the main body inner space formed by the main body inner peripheral surface of the main body and the cooling medium supply path. Thereby, it is possible to suppress the cooling medium from being dispersed before reaching the cutting edge of the tool by centrifugal force.

International Publication WO2014 / 167669

The tool holder disclosed in Patent Document 1 can supply a cooling medium to the cutting edge of the tool while suppressing the influence of centrifugal force, and can effectively cool the tool.
However, the tool holder disclosed in Patent Document 1 has a limit in enhancing the cooling effect of the tool.
The present invention has been made in view of such a point, and an object thereof is to provide a tool holder capable of enhancing the cooling effect of a tool held by the tool holder.

The tool holder of the present invention has a tool holder tip surface and a tool holder inner peripheral surface. The tool holder tip surface is formed on the tip side (tool insertion side) along the axial direction. The inner peripheral surface of the tool holder has an opening at the tip end surface of the tool holder and forms a tool insertion space into which a tool (specifically, a tool shank portion) can be inserted. The tool inserted into the tool insertion space can be held by bringing at least a part of the inner peripheral surface of the tool holder into contact with the outer peripheral surface of the tool. For example, a part of the inner peripheral surface of the tool holder is elastically deformed by hydraulic pressure or the like, or by using a shrink-fit tool holder (referred to as a “shrink-fit holder”) (heated and expanded tool insertion) The tool holder is cooled after being inserted into the space), and at least a part of the inner peripheral surface of the tool holder is brought into contact with the outer peripheral surface of the tool.
An injection port for injecting a cooling medium is formed on the tip end surface of the tool holder at a position radially outside the opening of the tool insertion space. At least one (one or more) injection ports are formed. When forming a plurality of injection ports, it is preferable to form them at equally spaced positions along the circumferential direction. As the cooling medium, for example, a coolant such as lubricating oil, grinding oil or water is used.
The cooling medium is supplied to the injection port via the first passage, the second passage, and the third passage. The first passage communicates with the injection port and extends along the axial direction. A 2nd channel | path is comprised by the groove | channel formed so that it might extend along the axial direction in the location containing the part contact | abutted to the outer peripheral surface of a tool of the inner peripheral surface of a tool holder. The grooves formed on the inner peripheral surface of the tool holder are linearly parallel to the axial direction (including “substantially parallel”), grooves extending along the axial direction (straight grooves), and spirally in the axial direction. The groove | channel (helical groove | channel) etc. which extend along are contained. At least one (one or more) grooves are formed. When forming a plurality of grooves, it is preferable to form them at equal intervals along the circumferential direction. The third passage is formed so as to connect a portion on the front end side along the axial direction of the second passage and a portion on the rear end side along the axial direction of the first passage. The first passage is formed in an inclined shape along the axial direction so that a portion on the rear end side along the axial direction is disposed radially outside the injection port. For example, the angle between the extending direction of the first passage and the axial direction is set so that the cooling medium injected from the injection port reaches the cutting edge of the tool when the tool is held in the tool insertion space. Is set. The inclination angle of the first passage is set according to the number of injection ports (first passages), the cross-sectional area of each part of the first passage, and the like. The first passage may be formed so that the position along the circumferential direction of the portion on the front end side and the position along the circumferential direction of the portion on the rear end side are the same when viewed from a direction perpendicular to the axial direction. Alternatively, the position along the circumferential direction of the portion on the front end side and the position along the circumferential direction of the portion on the rear end side may be different. The shapes of the first to third passages can be changed as appropriate. For example, the flow rate of the cooling medium can be changed by changing the cross-sectional area of the passage. Further, it may be formed in a straight line shape or a spiral shape.
In the present invention, since the cooling medium injected from the injection port formed on the tip surface of the tool holder can be prevented from being separated by the centrifugal force before reaching the cutting edge of the tool, the cutting edge of the tool is effective. Can be cooled to. Furthermore, the cooling medium before being injected from the injection port is configured by a groove formed so as to extend along the axial direction at a location including a portion of the inner peripheral surface of the tool holder that contacts the outer peripheral surface of the tool. The tool (tool shank portion) held in the tool insertion space is cooled by passing the second passage. Thereby, the cooling effect of a tool can be heightened.
In a different form of the present invention, the third passage connecting the first passage and the second passage is preferably axially extended from the inner peripheral side to the outer peripheral side along the radial direction. Are formed at right angles (including “substantially right angles”). That is, preferably, the end on the front end side along the axial direction of the second passage and the end on the rear end side along the axial direction of the first passage are in the radial direction in a cross section perpendicular to the axial direction. The third path is formed so as to extend along the straight line.
In this embodiment, the coolant that has flowed along the axial direction through the second passage flows through the third passage by flowing from the inner peripheral side to the outer peripheral side along the radial direction through the third passage. The speed of the cooling medium can be increased by the action of centrifugal force. Further, the cooling medium whose temperature has been increased by cooling the tool shank portion inserted into the tool insertion space can be moved away from the tool, and the temperature of the cooling medium can be lowered. Thereby, while cutting a tool shank part, the blade edge of a tool can also be cooled effectively and the cooling effect of a tool can be heightened more.
In another different form of the present invention, a first member having a first inner peripheral surface and a second member having a second inner peripheral surface and attached to the first member are provided. The tool holder front end surface is formed on the second member. The tool holder inner peripheral surface is formed by the first inner peripheral surface of the first member and the second inner peripheral surface of the second member. Of the first passage and the third passage, at least the first passage is formed in the second member. Suitably, a 2nd member is comprised as a cover which covers the front end surface of a 1st member.
In this embodiment, by changing the shape of the first passage formed in the second member, the injection direction and the injection amount of the cooling medium injected from the injection port are changed to the opening (tool holder tip) of the tool insertion space. It can be set appropriately according to the length of the tool protruding from the surface).
In another different form of the present invention, the first member is constituted by a main body portion and a sleeve. The main body has an inner peripheral surface of the main body that forms the inner space of the main body. Further, the sleeve has a sleeve inner peripheral surface forming a sleeve inner space and is disposed in a part of the main body inner space. The sleeve holder inner peripheral surface and the second inner peripheral surface form a tool holder inner peripheral surface.
For example, the sleeve is configured such that a part of the inner peripheral surface of the sleeve can be elastically deformed. Preferably, a pressurizing space is formed between the inner peripheral surface of the main body and the outer peripheral surface of the sleeve at a part of the sleeve, and the pressurizing space of the sleeve is changed by changing the pressure in the pressurizing space. The formed portion is configured to be elastically deformable.
In this embodiment, the tool (tool shank portion) can be held in the tool insertion space with a simple configuration.
In another different form of the present invention, the second member is configured to be detachable from the first member, and a plurality of the second members are provided. Each second member is configured so that at least one of the injection direction and the injection amount of the cooling medium injected from the injection port is different.
In the present embodiment, a tool in which the injection direction and the injection amount of the cooling medium injected from the injection port can be easily projected from the opening (tool holder tip surface) of the tool insertion space by exchanging the second member. It can be set appropriately according to the length (protrusion length).

  The tool holder of the present invention can enhance the cooling effect of the tool.

It is a side view of one Embodiment of the tool holder of this invention. It is the figure which expanded the cross section of the part shown by the arrow II of FIG. It is sectional drawing seen from the III-III line direction of FIG. It is the figure seen from the IV-IV line direction of FIG. It is a figure which shows the state which attached the cover corresponding to the tool protrusion length A. It is a figure which shows the state which attached the cover corresponding to tool protrusion length B (B <A). It is a figure which shows the state which attached the cover corresponding to tool protrusion length C (C <B).

Embodiments of the present invention will be described below with reference to the drawings.
In this specification, the extending direction (the x direction shown in FIG. 1) of the tool holder (main body portion, sleeve, cover) is referred to as “axial direction”. In the cross section perpendicular to the axial direction (FIGS. 3 and 4), the direction along the arc centered on the rotation center of the tool holder (main body, sleeve, cover) is called “circumferential direction”. The direction of the line passing through is called “radial direction”. Further, a side along which the tool is inserted along the axial direction is referred to as “front end side”, and a side opposite to the side where the tool is inserted is referred to as “rear end side”.

An embodiment of the tool holder of the present invention will be described with reference to FIGS. FIG. 1 is a side view of a tool holder 100 according to an embodiment. 2 is an enlarged view of a cross section of a portion indicated by an arrow II in FIG. 1, FIG. 3 is a cross sectional view taken along the line III-III in FIG. 2, and FIG. It is sectional drawing seen from the IV-IV line direction.
The tool holder 100 according to this embodiment includes a main body 200, a sleeve 300, and a cover 400. The sleeve 300 is fixed to the main body 200. The tool holder 100 is made of, for example, steel.

The main body 200 has a main body inner peripheral surface 210 and a main body outer peripheral surface 230. Moreover, it has the main-body-part front end surface 200a in the front end side (right side of FIG. 1) along an axial direction.
A main body inner space 220 extending along the axial direction is formed by the main body inner peripheral surface 210. The main body inner peripheral surface 210 has a circular shape centered on the center of rotation when viewed in a cross section perpendicular to the axial direction.
The main body outer peripheral surface 230 has a shank portion 231 on the rear end side along the axial direction, and a cover attachment portion 232 to which a cover 400 described later is attached on the front end side along the axial direction. The shank portion 231 is gripped by a gripping mechanism (not shown) provided in the machine tool and is connected to the spindle of the machine tool.
The shank portion 231 of the main body outer peripheral surface 230 corresponds to the “first outer peripheral surface portion” of the present invention, and the cover mounting portion 232 corresponds to the “second outer peripheral surface portion” of the present invention.

The sleeve 300 has a sleeve inner peripheral surface 310 and a sleeve outer peripheral surface 330. In addition, a sleeve front end surface 300a is provided on the front end side along the axial direction, and a sleeve rear end surface (not shown) is provided on the rear end side.
The sleeve inner peripheral surface 310 forms a sleeve inner space 320 extending along the axial direction. The sleeve inner peripheral surface 310 has a circular shape centered on the center of rotation when viewed in a cross section perpendicular to the axial direction.
The sleeve outer peripheral surface 330 has a circular shape centered on the center of rotation when viewed in a cross section perpendicular to the axial direction.
The sleeve outer peripheral surface 330 is formed with a first gripping portion outer peripheral surface 331 and a second gripping portion outer peripheral surface 332 in a stepped shape on the rotation center side at locations separated along the axial direction. Yes.
In the present embodiment, the outer diameter of the sleeve outer peripheral surface 330 is set to be slightly smaller than the inner diameter of the portion corresponding to the sleeve mounting portion 211 of the main body inner peripheral surface 210. Then, after the sleeve 300 is inserted into a main body inner space (sleeve insertion space) formed by the sleeve mounting portion 211 of the main body inner peripheral surface 210, the sleeve outer peripheral surface 330 is brazed to the sleeve mounting portion 211. . As a result, the sleeve outer peripheral surface 330 is tightly fixed to the sleeve mounting portion 211 of the main body inner peripheral surface 210, and the first gripper outer peripheral surface 331 and the second gripper outer peripheral surface 332, and the sleeve of the main body inner peripheral surface 210. A first pressurizing space 341 and a second pressurizing space 342 having high airtightness are formed by the attachment portion 211. Further, the first grip portion 351 and the second grip portion outer peripheral surface 331 and the second grip portion outer peripheral surface 332 and the sleeve inner peripheral surface 310 of the sleeve outer peripheral surface 330 are spaced apart from each other in the axial direction. Two grip portions 352 are formed. The sleeve inner space 320 has an opening that opens to the sleeve distal end surface 300a on the distal end side along the axial direction, and communicates with the main body inner space 220 on the rear end side along the axial direction.
The sleeve inner peripheral surface 310 is formed with a groove extending along the axial direction. The groove formed on the sleeve inner peripheral surface 310 is, for example, a straight line parallel to the axial direction (including “substantially parallel”), a groove extending along the axial direction (straight groove), and a spiral shape. A groove (helical groove) extending along the axial direction is included. In the present embodiment, as shown in FIGS. 2 and 3, two grooves 361 and 362 extending along a straight line parallel to the axial direction are formed at equal intervals along the circumferential direction. ing. The grooves 361 and 362 will be described later.

  In the present embodiment, the main body 200 and the sleeve 300 constitute the “first member” or “tool holding portion” of the present invention. Further, the main body portion front end surface 200a on the front end side along the axial direction of the main body portion 200 and the sleeve front end surface 300a on the front end side along the axial direction of the sleeve 300, the "first member of the present invention, A tip surface on the tip side along the axial direction is formed.

A pressurized medium is injected into the first pressurized space 341 and the second pressurized space 342. In the present embodiment, a liquid such as oil is used as the pressurizing medium. A pressure adjusting device that adjusts the pressure in the first pressurizing space 341 and the second pressurizing space 342 is provided.
When the pressure in the first pressurizing space 341 and the second pressurizing space 342 applied to the first gripping portion outer peripheral surface 331 and the second gripping portion outer peripheral surface 332 increases, the first gripping portion 351 is increased. And the second grip 352 (that is, the portion of the sleeve inner peripheral surface 310 corresponding to the first grip 351 and the second grip 352) are elastically deformed toward the center of rotation, and the first grip 351 And the internal diameter of the 2nd holding | grip part 352 reduces (reducing diameter). As a result, the tool shank portion of the tool inserted into the sleeve inner space 320 is held between the first grip portion 351 and the second grip portion 352.
When the pressure in the first pressurizing space 341 and the second pressurizing space 342 decreases, the first gripping part 351 and the second gripping part 352 return to the shape before elastic deformation, and the first gripping part The clamping of the tool shank portion of the tool 500 by the 351 and the second gripping portion 352 is released.

The cover 400 is formed in a bottomed cylindrical shape, and has a bottom portion 401 and a cylindrical portion 402.
The bottom portion 401 is disposed along the radial direction. The bottom portion 401 has a cover front end surface 400a disposed on the front end side along the axial direction, and a bottom inner peripheral surface 400b disposed on the rear end side along the axial direction. Further, the bottom 401 has a cover inner peripheral surface 410, and the cover inner peripheral surface 410 forms a cover inner space 420 extending in the axial direction. The cover inner space 420 has an opening 420a on the front end side along the axial direction, and an opening 420b on the rear end side along the axial direction. The opening 420a is formed in the cover front end surface 400a. In addition, since the recessed part 490 mentioned later is formed in the bottom inner peripheral surface 400b of the bottom part 401, the opening part 420b is formed in the bottom face of the recessed part 490.
The cylindrical portion 402 is disposed so as to extend from the outer periphery on the rear end side along the axial direction of the bottom portion 401 to the rear end side along the axial direction. The tubular portion 402 has a tubular portion inner peripheral surface 430. The cylindrical portion inner circumferential surface 430 forms a cylindrical portion inner space extending along the axial direction. The cylindrical portion inner peripheral surface 430 is formed in a shape corresponding to the shape of the cover attaching portion 232 of the main body portion outer peripheral surface 230. In the present embodiment, the cylindrical portion inner peripheral surface 430 is configured to be screwable with the cover mounting portion 232. That is, the cover 400 is configured to be detachable from the main body 200. The cover 400 is attached to the main body 200 such that the bottom inner peripheral surface 400b of the bottom 401 of the cover 400 abuts on the main body front end surface 200a of the main body 200.

  In the present embodiment, the cover 400 corresponds to the “second member” of the present invention, and the cover front end surface 400a of the cover 400 corresponds to the “tool holder front end surface” of the present invention. The “tool holder inner peripheral surface” of the present invention is formed by the main body inner peripheral surface 210 of the main body 200, the sleeve inner peripheral surface 310 of the sleeve 300, and the cover inner peripheral surface 410 of the cover 400. The space 320 and the cover inner space 420 of the cover 400 form the “tool insertion space formed by the inner peripheral surface of the tool holder” in the present invention. In addition, the configuration corresponding to the first gripping portion 351 and the second gripping portion 352 of the sleeve inner peripheral surface 310 is brought into contact with the outer peripheral surface of the tool (tool shank portion) inserted into the tool insertion space. Corresponds to the “configuration in which a part of the inner peripheral surface of the tool holder is brought into contact with the outer peripheral surface of the tool inserted into the tool insertion space” of the present invention.

Next, the cooling medium supply mechanism of this embodiment will be described.
Since the tool holder is rotating, when the cooling medium is sprayed from the spray port provided in the tool holder toward the cutting edge of the tool held by the tool holder, the coolant is sprayed from the spray port due to the influence of centrifugal force. It is necessary to prevent the cooling medium from separating before reaching the cutting edge of the tool. As the cooling medium, coolant such as lubricating oil, grinding oil or water is used.
In the present embodiment, as shown in FIG. 2, an injection port is formed on the cover front end surface 400 a on the front end side in the axial direction of the cover 400 on the radially outer side from the opening 420 a of the cover inner space 420. In the present embodiment, two injection ports 471a and 472a are formed at equal intervals along the circumferential direction.
In addition, the cooling medium injected from the injection ports 471a and 472a supplies the cooling medium to the injection ports 471a and 472a so that the cooling medium can reliably reach the cutting edge of the tool even when centrifugal force is applied. The injection passages 471 and 472 are formed in an inclined shape along the axial direction. In the present embodiment, the distance along the radial direction from the center of rotation of the portion on the rear end side along the axial direction of the injection passage 471 (472) is the portion on the front end side along the axial direction (cover front end surface 400a). Of the injection port 471a (472a)) is longer than the distance along the radial direction from the rotation center, that is, the rear end side portion of the injection passage 471 (472) is the injection port 471a ( 472a) is inclined so as to be arranged radially outward.
Thereby, the part of the blade edge of the tool held by the tool holder 100 can be reliably cooled.

In this embodiment, the tool shank part of the tool currently hold | maintained at the tool holder 100 is cooled using the cooling medium supplied to the injection nozzles 471a and 472a.
That is, as shown in FIG. 2, a groove extending along the axial direction is formed on the sleeve inner peripheral surface 310 forming the sleeve inner space 320 into which the tool shank portion of the tool is inserted. doing. In the present embodiment, two grooves 361 and 362 extending along a straight line parallel to the axial direction (including “substantially parallel”) are formed at equal intervals along the circumferential direction. The grooves 361 and 362 communicate with the sleeve front end surface 300a on the front end side along the axial direction (the sleeve front end surface 300a has an opening), and on the rear end side along the axial direction, the main body inner space 220. Communicating with In the present embodiment, the cooling medium is supplied to the grooves 361 and 362 through the main body portion inner space 220. As a result, the sleeve is inserted into the sleeve inner space 320 and is held by the portions of the sleeve inner peripheral surface 310 corresponding to the first grip portion 351 and the second grip portion 352 coming into contact with the outer peripheral surface of the tool shank portion. The existing tool is cooled by the cooling medium flowing through the grooves 361 and 362.

Further, connection passages for supplying the cooling medium passing through the grooves 361 and 362 formed in the sleeve inner peripheral surface 310 to the injection passages 471 and 472 are formed.
In the present embodiment, a concave portion that communicates a portion on the front end side along the axial direction of the grooves 361 and 362 and a portion on the rear end side along the axial direction of the injection passages 471 and 472 in the bottom inner peripheral surface 400b of the cover 400. 490 is formed. In the present embodiment, as shown in FIG. 4, when viewed from the direction perpendicular to the axial direction, the tip side portions along the axial direction of the grooves 361 and 362 and the axial direction of the injection passages 471 and 472 are arranged. A circular recess 490 including a rear end portion is formed.
In addition, when the bottom inner peripheral surface 400b of the cover 400 abuts (contacts) the main body portion tip surface 200a of the main body portion 200, a connection passage that connects the grooves 361 and 362 and the injection passage 471.472 is formed. The cross-sectional area and depth of the recess 490 are set according to the required flow rate of the cooling medium flowing through the connection passage formed by the recess 490. When the space of the recess 490 (the space of the connection passage) is formed larger than the space of the injection passages 471 and 472 and the cooling medium can be stored, the cooling liquid is stably injected from the injection ports 471 and 472. be able to.
By setting the cross-sectional shape of the recess 490 to a circular shape, it is possible to easily cope with a change in the number and position of the injection passage communicating with the groove and the injection port formed in the sleeve inner peripheral surface 310 along the circumferential direction. it can.

Further, in the present embodiment, when viewed from the direction perpendicular to the axial direction, the position along the circumferential direction of the tip side portion along the axial direction of the groove 361 (362) formed in the sleeve inner circumferential surface 310; The rear passage side portion along the axial direction of the injection passage 471 (472) is configured so that the position along the circumferential direction is the same (arranged on a straight line along the radial direction).
As described above, since the connecting passage extends from the inner peripheral side to the outer peripheral side along the radial direction, when the cooling medium flows through the connecting passage, centrifugal force is applied to the cooling medium flowing through the connecting passage. The speed of the cooling medium can be increased.
Further, the cooling medium whose temperature has been increased by cooling the tool shank portion of the tool is moved from the inner peripheral side to the outer peripheral side along the radial direction via the connection passage, that is, separated from the tool shank portion. As a result, the temperature of the cooling medium can be lowered. Thereby, the cooling medium whose temperature has decreased can be ejected from the ejection ports 471a and 472a. That is, using the same cooling medium, the tool edge can be cooled while cooling the tool shank portion of the tool held by the tool holder 100, and the cooling effect of the tool can be enhanced with a simple configuration. .

In addition, a sealing member is provided to prevent the cooling medium flowing through the connection passages formed by the grooves 361 and 361 and the recesses 490 and the injection passages 471 and 472 from leaking to the outside. In the present embodiment, the cooling medium is prevented from leaking to the outside through the gap between the main body 200 and the cover 400 and the gap between the tool inserted into the cover inner space 420 and the cover inner peripheral surface 410. For this purpose, O-rings 450 and 460 are provided.
The shape of the recess 490 (the shape of the bottom surface of the recess 490) is not limited to a circular shape as long as the grooves 361 and 362 can be connected to the injection passages 471 and 472.
Further, a recess 490 is formed in the bottom inner peripheral surface 400b of the cover 400, and a connection passage is formed by closing the concave portion 490 by bringing the bottom inner peripheral surface 400b of the cover 400 into contact with the main body portion front end surface 200a. However, the method of forming the connection passage is not limited to this.
In the present embodiment, the injection passages 471 and 472 correspond to the “first passage” of the present invention, and the grooves 361 and 362 formed in the sleeve inner peripheral surface 310 serve as the “second passage” of the present invention. Correspondingly, the connection passage formed by the recess 490 corresponds to the “third passage” of the present invention.

In the present embodiment, the cover 400 is configured to be detachable from the main body 200.
In addition, the length (protrusion length) between the cutting edge of the tool and the front end surface (cover front end surface 400a of the cover 400) along the axial direction of the tool holder 100 in a state where the tool is held in the tool holder 100. ) Depends on the tool.
Therefore, a plurality of covers 400 corresponding to the tool protrusion length are provided as the cover 400, and an appropriate cover 400 is selected according to the tool protrusion length and attached to the main body 200, whereby each tool having a different protrusion length is provided. Can be effectively cooled.
FIG. 5 shows a state in which an example of a cover 400 </ b> A used when the protruding length of the tool 500 held by the tool holder 100 is [A] is attached to the main body 200. In the cover 400A, the angle between the extending direction of the injection passages 471 and 472 (the injection direction of the cooling medium injected from the injection ports 471a and 472a) and the axial direction is set to θa.
FIG. 6 shows a state in which an example of a cover 400B used when the protruding length of the tool 500 held by the tool holder 100 is [B (B <A)] is attached to the main body 200. . In the cover 400B, the angle between the extending direction of the injection passages 471 and 472 and the axial direction is set to θb (θb> θa).
FIG. 7 shows a state where an example of a cover 400C used when the protruding length of the tool 500 held by the tool holder 100 is [C (C <B)] is attached to the main body 200. . In the cover 400C, an angle between the extending direction of the injection passages 471 and 472 and the axial direction is set to θc (θc> θb).

The present invention is not limited to the configuration described in the embodiment, and various changes, additions, and deletions can be made without departing from the scope of the present invention.
The method for elastically deforming a part of the sleeve inner peripheral surface (tool holder inner peripheral surface) is not limited to the method described in the embodiment (method for adjusting the pressure in the pressurization space formed on the sleeve outer peripheral side). .
As a method of abutting at least a part of the sleeve inner peripheral surface (tool holder inner peripheral surface forming the tool insertion space) forming the sleeve inner space with the outer peripheral surface of the tool (tool shank part), the sleeve inner space (tool The method is not limited to the method of elastically deforming at least a part of the holder inner peripheral surface), and a method using a shrink-fit tool holder (referred to as “shrink-fit holder”) can also be used. When using the shrink fit holder, the tool insertion space is heated to expand, and the tool is inserted into the expanded tool insertion space and then cooled.
In the embodiment, when the injection passage (first passage) is viewed from the direction perpendicular to the axial direction, the position along the circumferential direction of the rear end portion and the position along the circumferential direction of the tip end portion are the same. However, the position along the circumferential direction of the rear end portion and the position along the circumferential direction of the tip end portion may be different.
In the embodiment, a groove (straight groove) extending along a straight line parallel to the axial direction is formed on the sleeve inner peripheral surface (tool holder inner peripheral surface). However, the sleeve extends spirally along the axial direction. A groove (spiral groove) can also be formed.
The number, shape, cross-sectional area, and the like of the injection ports can be changed as appropriate. Further, the cross-sectional area, the inclination angle, the inclination direction, the length, and the like of the first passage can be changed as appropriate. In addition, the cross-sectional area and length of the second passage can be changed as appropriate. In addition, a flow velocity changing unit (for example, an orifice) that changes the flow velocity of the cooling medium by changing the cross-sectional area of the passage may be provided in the middle of the passage. In addition, when providing a plurality of injection ports, first passages, and second passages, it is preferable to form them at equal intervals along the circumferential direction.
In the embodiment, the first passage and the third passage are formed in the cover, but it is sufficient that at least the first passage is formed in the cover.
The configurations of the main body, the sleeve, and the cover are not limited to the configurations shown in the embodiments.
Although the tool holding part is constituted by the main body part and the sleeve, the tool holding part can be constituted alone.
Although the tool holder is constituted by the main body part, the sleeve and the cover, the tool holder can be constituted alone. In this case, the cover is not configured to be detachable.
Each structure demonstrated by embodiment can also be used independently, and can also be used combining the plurality selected suitably.

DESCRIPTION OF SYMBOLS 100 Tool holder 200 Main body part 200a Main body part front end surface 210 Main body part inner peripheral surface 220 Main body part inner space 230 Main body part outer peripheral surface 231 First outer peripheral surface part 232 Second outer peripheral surface part 300 Sleeve 300a Sleeve front end surface 310 Sleeve inner peripheral part Surface 320 Sleeve inner space 330 Sleeve outer peripheral surface 331 First gripping portion outer peripheral surface 332 Second gripping portion outer peripheral surface 341 First pressurizing space 342 Second pressurizing space 351 First gripping portion 352 Second gripping 361, 362 groove (second passage)
400, 400A, 400B, 400C Cover 400a Cover tip surface 400b Bottom inner circumferential surface 401 Bottom 402 Tubular portion 410 Cover inner circumferential surface 420 Cover inner space 430 Tubular portion inner circumferential surface 450, 460 O-rings 471, 472 Injection passage (first 1 passage)
471a, 472a Injection port 490 Connection passage (third passage)
500 tools

Claims (5)

A tool holder front end surface formed on the front end side along the axial direction; and a tool holder inner peripheral surface having an opening in the tool holder front end surface and forming a tool insertion space into which a tool can be inserted. A tool holder configured to be able to hold a tool inserted into an insertion space by bringing at least part of the inner peripheral surface of the tool holder into contact with the outer peripheral surface of the tool,
An injection port that is formed at a position radially outside of the opening of the tool holder tip surface and injects a cooling medium;
A first passage extending along the axial direction, communicating with the injection port;
A second passage formed of a groove formed so as to extend along the axial direction at a location including a portion of the inner peripheral surface of the tool holder that contacts the outer peripheral surface of the tool;
A third passage connecting a portion on the front end side along the axial direction of the second passage and a portion on the rear end side along the axial direction of the first passage;
The tool holder is characterized in that the first passage is inclined so that a portion on a rear end side along the axial direction is disposed radially outside the injection port. The tool holder according to claim 1,
The tool holder, wherein the third passage is formed so as to extend from the inner peripheral side to the outer peripheral side along the radial direction. The tool holder according to claim 1 or 2,
A first member having a first inner peripheral surface and a second member having a second inner peripheral surface and attached to the first member;
The tool holder front end surface is formed on the second member,
The tool holder inner peripheral surface is formed by the first inner peripheral surface and the second inner peripheral surface,
Of the first passage and the third passage, at least the first passage is formed in the second member. A tool holder according to claim 3,
The first member includes a main body portion and a sleeve,
The main body has a main body inner peripheral surface forming a main body inner space,
The sleeve has a sleeve inner peripheral surface forming a sleeve inner space, and is disposed in a part of the main body inner space,
The tool holder inner peripheral surface is formed by the sleeve inner peripheral surface and the second inner peripheral surface. The tool holder according to claim 3 or 4,
A plurality of the second members are provided,
Each of the second members is detachable from the first member, and is configured so that at least one of the injection direction and the injection amount of the cooling medium injected from the injection port is different. Tool holder.

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