JP2017061010A - Tool holder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool holder which enables improvement of vibration inhibition effect.SOLUTION: A tool holder 100 has a holding part comprising a body part 110 and a holding part 120. A cylindrical space part 140 is formed by an outer peripheral surface 113 and a stepped surface 114 of the body part 110 and a cover 130. A ring-shaped member 150 integrally formed in a circumferential direction is disposed in the space part 140. The ring-shaped member 150 has a clearance between a ring inner peripheral surface 151 of the ring-shaped member 150 and the body outer peripheral surface 113 of the body part 110 and is disposed so as to move relative to the body part 110. Further, the tool holder 100 is configured so that a ring outer peripheral surface 152 of the ring-shaped member 150 does not contact with a cover inner peripheral surface 131a of the cover 130.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a tool holder, and more particularly, to a tool holder including a vibration damping mechanism that suppresses vibrations generated during machining.

During metal cutting using a cutting tool, vibration (called “chatter vibration”) is generated in the tool holder that holds the cutting tool, and the processing accuracy decreases. For this reason, a vibration suppression mechanism that suppresses vibration generated in the tool holder is provided.
A tool holder provided with a vibration damping mechanism is disclosed in Patent Document 1, for example. In the vibration damping mechanism disclosed in Patent Document 1, a plurality of weight members having a fan-shaped cross-sectional shape are provided in a cylindrical hollow portion formed in a tool holder along a circumferential direction centering on a rotation center. They are arranged side by side. Each weight member is urged in the direction of the rotation center by the urging member so that the divided surfaces of adjacent weight members are in surface contact with each other.

JP 2012-57752 A

In the conventional tool holder, when vibration occurs in the tool holder, the divided surfaces of the adjacent weight members slide with each other, and vibration energy is absorbed as friction energy, thereby suppressing vibration. However, the vibration damping mechanism used in the conventional tool holder has a limit in increasing the vibration suppression effect.
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 vibration suppression effect.

The tool holder of the present invention includes a holding portion that has a tool insertion space on the inner side and is configured to be able to grip a tool inserted into the tool insertion space. As a gripping mechanism for gripping the tool inserted into the tool insertion space, various known gripping mechanisms using a liquid such as oil or shrink fitting can be used.
The tool holder includes a vibration control mechanism that suppresses vibration of the tool holder. The vibration control mechanism has a ring-shaped member that is disposed outside the holding portion and is integrally formed in the circumferential direction. The “ring-shaped member integrally formed in the circumferential direction” is preferably a “cylindrical member”, typically a cylindrical member having a circular shape on the inner side and the outer side. The “ring shape integrally formed along the circumferential direction” includes not only a shape closed along the circumferential direction but also a part along the circumferential direction when viewed in a cross section perpendicular to the axial direction. Missing shapes are also included.
The ring-shaped member is disposed so as to be relatively movable with respect to the holding portion with a clearance (gap along the radial direction) between the inner side of the ring-shaped member and the outer side of the holding portion. Has been. The ring-shaped member may be at least relatively movable along the radial direction with respect to the holding portion, but is preferably disposed so as to be relatively movable along the radial direction and the axial direction with respect to the holding portion. . In the configuration having “a clearance between the inner side of the ring-shaped member and the outer side of the holding portion”, the interval along the radial direction on the inner side of the ring-shaped member is typically The structure set larger than the space | interval along the radial direction of an external side respond | corresponds. The length, arrangement position, and the like along the axial direction of the ring-shaped member are appropriately set so that the vibration of the tool holder can be effectively suppressed.
The present invention is configured such that the outer side of the holding portion and the inner side of the ring-shaped member abut when vibration is generated.
Preferably, the ring-shaped member is attached to be exchangeable so that the clearance (gap) between the inner side of the ring-shaped member and the outer side of the holding portion can be adjusted.
In the present invention, when vibration occurs, the vibration energy is absorbed by the collision energy caused by the contact between the outer side of the holding portion and the inner side of the ring-shaped member. Thereby, the vibration suppression effect of a tool holder can be improved significantly.
In a different form of the present invention, a cover is provided outside the holding portion and covers the outer side of the holding portion along the circumferential direction, and a space portion is formed by the outer side of the holding portion and the inner side of the cover. Preferably, a closed space portion is formed by the outer peripheral surface of the holding portion and the cover. The ring-shaped member is disposed in the space portion. Here, the outer side of the ring-shaped member is configured not to contact the inner side of the cover.
In this embodiment, since the cover is provided outside the ring-shaped member, it is possible to prevent dust and the like from entering between the outer side of the holding portion and the inner side of the ring-shaped member. Thereby, it can prevent that the vibration suppression effect falls by garbage etc.
In another different form of the present invention, the ring-shaped member is formed of a material having a specific gravity greater than that of the material forming the holding portion. Typically, the holding portion is made of steel, and the ring-shaped member is made of cemented carbide.
In this embodiment, since the ring-shaped member is formed of a material having a specific gravity greater than that of the material forming the holding member, the vibration suppressing effect due to the contact between the ring-shaped member and the holding portion can be further enhanced.
In another different form of the present invention, the ring-shaped member has a plurality of divided ring-shaped members arranged along the axial direction.
In this embodiment, the vibration energy is absorbed by the collision energy caused by the contact between the outer peripheral portion of the holding portion and the inner peripheral portion of the ring-shaped member and the friction energy generated by sliding between the adjacent divided ring-shaped members. Can do. Thereby, the vibration suppression effect can be further enhanced.
In another different aspect of the present invention, the maximum value of the clearance between the inner side of at least one of the plurality of divided ring-shaped members and the outer side of the holding portion is determined by the other divided ring-shaped members. This is different from the maximum value of the clearance between the inner side of the holder and the outer side of the holding portion.
In this embodiment, the contact timing between the outer side of the holding portion and the inner side of the split ring member can be changed. Thereby, even when the amplitude of vibration is different, vibration can be effectively suppressed.
In another different form of the present invention, the inner side of the ring-shaped member is formed in a tapered shape in which the distance along the radial direction decreases sequentially toward the distal end side, and the outer side of the holding portion extends along the radial direction. It is formed in a taper shape in which the interval decreases sequentially toward the tip side. The interval along the radial direction of the ring-shaped member and the interval along the radial direction of the holding portion typically correspond to the inner diameter of the ring-shaped member and the outer diameter of the holding member.
In this embodiment, when the outer side of the holding part and the inner side of the ring-shaped member come into contact with each other, the outer side of the holding part and the inner side of the ring-shaped member slide along the tapered surface. Thus, vibration energy can be absorbed by collision energy caused by contact between the outer side of the holding portion and the inner side of the ring-shaped member and friction energy generated by sliding between the outer side of the holding portion and the inner side of the ring-shaped member. And the vibration suppressing effect can be further enhanced.
In another different form of the present invention, an adjustment mechanism is provided that can adjust the relative movement range of the ring-shaped member in the axial direction with respect to the holding portion. The adjustment mechanism should just be arrange | positioned with respect to the ring-shaped member at least one side along the axial direction. Preferably, a cover whose position along the axial direction is adjustable is provided outside the ring-shaped member. The cover has an outer peripheral wall extending along the circumferential direction, and an end wall that is connected to at least one side of both ends along the axial direction of the outer peripheral wall and extends along the radial direction. Yes.
In this embodiment, the movable range along the axial direction of the ring-shaped member can be adjusted. In particular, by combining the adjustment mechanism of the present embodiment with a configuration in which the outer side of the holding part and the inner side of the ring-shaped member are tapered (tapered surface), the outer side of the holding part and the inner side of the ring-shaped member The clearance between the two can be easily adjusted.
In another different aspect of the present invention, a buffer mechanism is provided that provides resistance to relative movement of the ring-shaped member with respect to the holding portion. As the buffer mechanism, for example, a buffer mechanism configured by a space portion in which a ring-shaped member is accommodated and a liquid such as oil or water or a gas such as air is enclosed, or a buffer mechanism configured by an elastic member such as a spring is used. Etc. can be used.
In this embodiment, vibration energy can be absorbed by suppressing the moving speed of the ring-shaped member, and the vibration suppression effect can be further enhanced.

  The tool holder of the present invention can enhance the vibration suppressing effect and can suppress a decrease in machining accuracy due to vibration.

It is sectional drawing of 1st Embodiment of the tool holder of this invention. It is an enlarged view of the part II of FIG. It is an enlarged view of the part III of FIG. It is the IV-IV sectional view taken on the line of FIG. It is a figure explaining the operation | movement outline | summary of the tool holder of 1st Embodiment. It is sectional drawing of the principal part of 2nd Embodiment of the tool holder of this invention. It is an enlarged view of the part VII of FIG. It is sectional drawing of the principal part of 3rd Embodiment of the tool holder of this invention. It is an enlarged view of the part IX of FIG.

Embodiments of the present invention will be described below with reference to the drawings.
In the present specification, the extending direction of the tool holder (direction along the rotation center line P: the x direction shown in FIG. 1) is referred to as “axial direction”. Further, in the cross section orthogonal to the axial direction (FIG. 4), the direction along the arc centering on the rotation center O of the tool holder is called “circumferential direction”, and the direction along the line passing through the rotation center O is “diameter”. "Direction".
Further, the side (right side in FIG. 1) where the tool is inserted into the tool insertion space along the axial direction is referred to as “tip side”.

  1st Embodiment of the tool holder of this invention is described with reference to FIGS. FIG. 1 is a cross-sectional view along the axial direction of the tool holder 100 according to the first embodiment. FIG. 2 is an enlarged view of part II of FIG. 1, and FIG. 3 is an enlarged view of part III of FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 1 (a cross-sectional view perpendicular to the axial direction).

The tool holder 100 according to the first embodiment includes a main body 100, a grip 120, and a cover 130. The tool holder 100 is driven by a drive unit (not shown) of the machine tool and rotates around the rotation center line P.
The main body 110 has a main body inner peripheral surface 111 on the inner side. A hollow portion 112 is formed inside the tool holder 100 by the inner peripheral surface 111.
The grip portion 120 is fixed to the distal end side of the cavity portion 112. The grip part 120 has a grip surface 121 on the inner side. A tool insertion space 122 is formed inside the grip portion 120 by the grip surface 121.
The tool shank portion 11 of the tool 10 is inserted into the tool insertion space 122. The tool shank portion 11 inserted into the tool insertion space 122 is gripped by the gripping surface 121. As the gripping mechanism for gripping the tool shank portion 11 by the gripping surface 121, for example, various known gripping mechanisms using a liquid such as oil or shrink fitting can be used. Since the configuration of these gripping mechanisms is known, description thereof is omitted in this specification.
When the tool holder 100 is driven and rotated by the drive unit, the tool 10 held by the holding unit 120 also rotates and is provided on the tip side of the tool 10 (the side not held by the holding unit 120: the right side in FIG. 1). It is possible to perform a machining operation using the blade portion (not shown).
Note that a cooling medium (for example, cooling oil) for cooling the tool 10 passes through the cavity 112, a passage formed in the tool 10, or a passage formed in the grip portion 120 or the main body 110. Supplied to the side.
The main body portion 110 and the grip portion 120 constitute a “holding portion” of the present invention.

  A main body outer peripheral surface 113 and a step surface 114 are formed on the outer side of the main body 110 (see FIGS. 2 and 3). The main body outer peripheral surface 113 extends along the circumferential direction and the axial direction. In the present embodiment, the outer peripheral surface 113 of the main body extends parallel to the axial direction, and has a circular shape centered on the rotation center O when viewed in a cross section perpendicular to the axial direction (see FIG. 4). doing. The step surface 114 extends outward in the radial direction from the end portion on the opposite side (left side in FIGS. 1 to 3) of the both ends along the axial direction of the outer peripheral surface 113 of the main body. Yes. Thus, a notch extending along the circumferential direction and the axial direction is formed on the outer periphery of the main body 110 by the main body outer peripheral surface 113 and the step surface 114.

A cover 130 is provided on the outer periphery of the main body 110 to cover a notch formed by the main body outer peripheral surface 113 and the step surface 114.
The cover 130 has an outer peripheral wall 131 and an end wall 132. The outer peripheral wall 131 extends along the circumferential direction and the axial direction, and has a cover inner peripheral surface 131a on the inner side. In the present embodiment, the outer peripheral wall 131 (cover inner peripheral surface 131a) extends parallel to the axial direction, and is centered on the rotation center O when viewed in a cross section perpendicular to the axial direction (see FIG. 4). It has a circular shape. The end wall 132 has a cover end surface 132a on the opposite side to the front end side and extends inward in the radial direction from the end on the front end side of both end portions along the axial direction of the outer peripheral wall 131. Yes. In the center of the end wall 132, an opening is formed into which a portion of the main body 110 surrounded by the outer peripheral surface 113 of the main body (hereinafter referred to as “the front end portion of the main body”) can be inserted.
In the present embodiment, the outer peripheral wall 131 has a cylindrical shape. That is, the cover 130 has a bottomed cylindrical shape with an end wall 132 having an opening at the center as a bottom wall.
A female screw 115 is formed on the outer peripheral surface on the distal end side of the distal end portion of the main body 110. A male thread 133 is formed in the opening of the end wall 132 of the cover 130. When the cover 130 is attached to the outer periphery of the main body 11, the male screw 133 formed in the opening of the end wall 132 of the cover 130 is connected to the female outer surface formed on the front end side of the front end portion of the main body 110. The screw 115 is screwed (engaged). By adjusting the screwing position (meshing position) of the male screw 133 and the female screw 115, the position along the axial direction of the cover 130 (end wall 132) can be adjusted.

A cylindrical space 140 extending along the circumferential direction and the axial direction is formed outside the main body 110 (the front end portion of the main body 110) by the main body outer peripheral surface 113, the step surface 114 and the cover 130 of the main body 110. It is formed. The space 140 is formed by the main body outer peripheral surface 113 and the step surface 114 of the main body 110, the cover inner peripheral surface 131 a and the cover end surface 132 a of the cover 130.
A ring-shaped member 150 is disposed in the space 140. The ring-shaped member 150 has a ring inner peripheral surface 151 formed on the inner side, a ring outer peripheral surface 152 formed on the outer side, and end surfaces 153 and 154 formed at both ends along the axial direction. And has a cylindrical shape extending along the axial direction. In this embodiment, as shown in FIG. 4, it has a circular shape closed along the circumferential direction when viewed in a cross section perpendicular to the axial direction. The ring-shaped member 150 is formed of a material having a specific gravity greater than that of the material forming the main body 110. In the present embodiment, the main body 110 is made of steel, and the ring-shaped member 150 is made of a super hard alloy (also referred to as “super hard alloy”) containing tungsten carbide and cobalt.
In addition, the ring-shaped member 150 can also be formed in a cylindrical shape having a cross-sectional shape (C shape) in which a part along the circumferential direction is cut out. In this case, the shape (interval or the like) of the notch portion is a range in which vibration energy can be absorbed by collision energy caused by contact between the outer peripheral surface 113 of the main body 110 and the inner peripheral surface 151 of the ring member 150. Set in.

In the present embodiment, when vibration occurs in the main body 110, the ring-shaped member 150 moves relative to the main body 110 (tip portion) along the radial direction, and the ring of the ring-shaped member 150. The inner peripheral surface 151 and the outer peripheral surface 113 of the main body 110 come into contact with each other, and vibration energy is absorbed by the collision energy generated by the contact between the inner peripheral surface 151 of the ring-shaped member 150 and the outer peripheral surface 113 of the main body 110. It is configured as follows.
Specifically, as shown in FIG. 4, the diameter (outer diameter) of the outer peripheral surface 113 of the main body 110 is K, the diameter (inner diameter) of the inner peripheral surface 151 of the ring-shaped member 150, and the outer periphery of the ring. When the diameter (outer diameter) of the surface 152 is L and M, and the diameter (inner diameter) of the cover inner peripheral surface 131a of the cover 130 is N, K is smaller than L, L is smaller than M, and M is smaller than N. Thus, the main body outer peripheral surface 113, the ring-shaped member 150, and the cover 130 of the main body 110 are formed (so that [K <L <M <N] is satisfied).
Thus, an inner space 141 is formed between the main body outer peripheral surface 113 of the main body 110 and the ring inner peripheral surface 151 of the ring-shaped member 150, and the ring outer peripheral surface 152 of the ring-shaped member 150 and the cover inner peripheral surface of the cover 130. An outer space 142 is formed between the surface 131a. That is, the space 140 is divided by the ring-shaped member 150 into an inner space 141 on the radially inner side and an outer space 142 on the radially outer side.

In addition, when the ring-shaped member 150 moves relative to the main body 110 along the radial direction due to vibration, the ring inner peripheral surface 151 of the ring-shaped member 150 and the main body outer peripheral surface 113 of the main body 110 can collide with each other. However, the ring outer peripheral surface 152 of the ring-shaped member 150 and the cover inner peripheral surface 131a of the cover 130 are configured not to contact each other.
Here, the distance S along the radial direction of the inner space 141 formed between the main body outer peripheral surface 113 of the main body 110 and the ring inner peripheral surface 151 of the ring-shaped member 150 and the ring outer peripheral surface of the ring-shaped member 150. The distance T along the radial direction of the outer space 142 formed between the cover 152 and the cover inner peripheral surface 131a of the cover 130 is such that the ring-shaped member 150 is relatively relative to the main body 110 along the radial direction. It changes by moving. Further, when one of the interval S of the inner space 141 and the interval T of the outer space 142 at any location along the circumferential direction increases, the other decreases. Therefore, in this embodiment, the maximum value of the interval T along the radial direction of the outer space 142 formed between the ring outer peripheral surface 152 of the ring-shaped member 150 and the cover inner peripheral surface 131a of the cover 130 is the main body. So as to be larger than the maximum value of the spacing S along the radial direction of the inner space 141 formed between the outer peripheral surface 113 of the main body 110 and the inner peripheral surface 151 of the ring-shaped member 150 (the maximum of T Value> maximum value of S] is set so that the ring outer peripheral surface 152 of the ring-shaped member 150 and the cover inner peripheral surface 131a of the cover member 150 do not come into contact with each other.

  The main body outer peripheral surface 131 of the main body 110 corresponds to the “inner side of the holding portion” of the present invention, and the ring inner peripheral surface 151 of the ring-shaped member 150 corresponds to the “inner side of the ring-shaped member” of the present invention. The ring outer peripheral surface 152 of the ring-shaped member 150 corresponds to “the outer side of the ring-shaped member” of the present invention, and the cover inner peripheral surface 131a of the cover portion 130 corresponds to “the inner side of the cover” of the present invention. . The inner space portion 141 corresponds to the “clearance (gap) formed between the inner side of the ring-shaped member and the outer side of the holding portion” of the present invention, and the outer space portion 142 corresponds to “ This corresponds to the “clearance (gap) formed between the outer side of the ring-shaped member and the inner side of the cover”.

In addition, since the ring-shaped member 150 can move relative to the main body 110 along the radial direction, the ring-shaped member 150 can move relative to the main body along the axial direction. It is configured. Specifically, as shown in FIG. 3, the length along the axial direction of the ring-shaped member 150 is H, and the distance along the axial direction of the space 140 (the stepped surface 114 of the main body 110 and the cover). When the distance between the end wall 132 of the cover 130 and the cover end surface 132a is G, H is smaller than G (so that [H <G] is satisfied). 110 main body outer peripheral surfaces 113 are formed and arranged.
Thereby, between the cover end surface 132a of the cover 130 and one end surface 153 (end surface on the front end side) of the ring-shaped member 150 and the other end surface 154 (end surface opposite to the front end side) of the ring-shaped member 150. A clearance (gap) is formed between the stepped surface 114 of the main body 110.
Note that the ring-shaped member 150 is relatively movable along the axial direction with respect to the main body 110, and the end surface 153 on one side and the end surface 154 on the other side of the ring-shaped member 150 are respectively covered by the cover 130. The end surface 132a and the step surface 114 of the main body 110 can be contacted. Therefore, the distance along the axial direction of the Clarins between the cover end surface 132a of the cover 130 and the one end surface 154 of the ring-shaped member 150 and the step surface of the other end surface 154 of the ring-shaped member 130 and the main body 110. The clearance along the axial direction of the clearance between the ring-shaped member 114 and the clearance 114 varies depending on the position of the ring-shaped member 150 along the axial direction.

Here, as described above, the male screw 133 formed in the opening of the end wall 132 of the cover 130 and the female screw 115 formed on the outer peripheral surface on the distal end side of the distal end portion of the main body 110 are screwed together. By adjusting the position (meshing position), the interval between the stepped surface 114 of the main body 110 and the cover end surface 132a of the cover 130, that is, the interval G along the axial direction of the space 140 can be adjusted. it can. Thereby, the relative movement range of the ring-shaped member 150 along the axial direction with respect to the main body 110 can be adjusted.
The end wall 132 of the cover 130, the female screw 115 formed on the outer peripheral surface on the distal end side of the distal end portion of the main body 110, and the male screw 133 formed on the opening of the end wall 132 of the cover 130. The “adjustment mechanism capable of adjusting the relative movement range of the ring-shaped member along the axial direction with respect to the holding portion” is configured.

An outline of the operation of this embodiment will be described with reference to FIG. In order to simplify the description, in FIG. 5, the main body 110 and the ring-shaped member 150 are represented by lines.
In a state where no vibration is generated in the tool holder 100, the main body 110 and the ring-shaped member 150 are assumed to be at positions 110 (a) and 150 (a) indicated by solid lines.
When vibration is generated in the tool holder 100 during processing, if the ring-shaped member 150 of this embodiment is not provided, the main body 110 uses the point on the drive unit side (the side opposite to the tip side) as a vibration center point. It vibrates to the positions 110 (b) and 110 (c) indicated by the broken lines.
On the other hand, when the ring-shaped member 150 of the present embodiment is provided, the main body 110 and the ring-shaped member 150 are positioned at the positions 110 (d) and 150 (d) indicated by the alternate long and short dashed lines, or 110 (e) and When moved to the position 150 (e), the main body outer peripheral surface 113 of the main body 110 and the ring inner peripheral surface 151 of the ring-shaped member 150 come into contact with each other to absorb vibration energy. Thereby, vibration is effectively suppressed.
In addition, since the vibration control mechanism provided in the conventional tool holder absorbs vibration energy by the frictional energy generated by sliding between the divided surfaces of adjacent weight members, the vibration energy absorption effect is enhanced. difficult.

A second embodiment of the tool holder of the present invention will be described with reference to FIGS. FIG. 6 is a cross-sectional view along the axial direction of the tool holder 200 of the second embodiment, and FIG. 7 is an enlarged view of a portion VII in FIG.
In the tool holder 200 of the present embodiment, the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 forming the space 240 in which the ring-shaped member 250 is accommodated are the same as those of the first embodiment. This is different from the main body outer peripheral surface 131 of the main body 110 and the ring inner peripheral surface 151 of the ring-shaped member 150. Other configurations are the same as those of the first embodiment. 6 and 7, the reference numerals assigned to the constituent elements except for the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 are shown in FIG. 2. Constituent elements to which the same reference numerals other than the hundreds are attached are the same. Therefore, only the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 will be described below.

In the present embodiment, the main body outer peripheral surface 213 of the main body 210 that forms the space 240 is formed in a tapered shape (tapered surface) in which the interval along the radial direction (outer diameter) decreases gradually toward the tip side. Has been. Further, the ring inner peripheral surface 251 of the ring-shaped member 250 facing the main body outer peripheral surface 213 of the main body 210 has a tapered shape (tapered surface) in which the radial interval (inner diameter) decreases sequentially toward the distal end side. Is formed. That is, the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 are formed as tapered surfaces extending in parallel.
As a result, in the present embodiment, when vibration occurs, the main body outer peripheral surface 213 of the main body 210 abuts on the ring inner peripheral surface 251 of the ring-shaped member 250 as in the first embodiment, and vibration is generated by the contact energy. Energy is absorbed.
Further, when the main body outer peripheral surface 213 of the main body 210 abuts on the ring inner peripheral surface 251 of the ring-shaped member 250, the main body outer peripheral surface 213 and the ring inner peripheral surface 251 are tapered surfaces. The inner peripheral surface 251 slides along the tapered surface. For this reason, vibration energy is absorbed by frictional energy generated by sliding between the outer peripheral surface 213 of the main body and the inner peripheral surface 251 of the ring.
Therefore, the contact energy between the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 and the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 The vibration energy can be absorbed by the frictional energy generated by the sliding movement, and the vibration suppressing effect is improved.

Moreover, this embodiment is provided with the adjustment mechanism which can adjust the relative movement range along the axial direction with respect to the main-body part 210 of the ring-shaped member 250 similarly to 1st Embodiment. The adjustment mechanism is formed in the end wall 232 (cover end surface 232 a) of the cover 230, the female screw 215 formed on the outer peripheral surface of the front end portion of the main body 210, and the opening of the end wall 232 of the cover 230. The male screw 233 is used. By adjusting the screwing position (biting position) of the male screw 233 and the female screw 215, the interval G along the axial direction of the space 240 can be adjusted.
Note that the end wall 232 and the cover end surface 232a of the cover 230 define a relative movable range along the axial direction of the ring-shaped member 250 with respect to the main body portion 210, and therefore, the “adjustment portion of the adjustment mechanism” and “adjustment mechanism”, respectively. It can be referred to as the “adjustment surface”.

In this embodiment, the main body outer peripheral surface 213 of the main body 210 and the ring inner peripheral surface 251 of the ring-shaped member 250 are formed in a tapered shape (tapered surface). The distance S along the radial direction of the ring inner peripheral surface 251 of 250 differs depending on the position of the cover member 250 along the axial direction with respect to the main body 210.
Therefore, by adjusting the position of the end wall 232 (cover end surface 232a) of the cover 230 along the axial direction with respect to the main body 210, the end surface 253 on the front end side of the ring-shaped member 250 contacts the cover end surface 232a of the cover 230. The distance S along the radial direction of the space 241 (clearance) between the outer peripheral surface 213 of the main body and the inner peripheral surface 251 of the ring can be adjusted.
That is, in the present embodiment, the distance S (clearance) along the radial direction between the outer peripheral surface 213 of the main body 210 and the inner peripheral surface 251 of the cover member 250 is adjusted without replacing the cover member 250. can do.
In addition, the structure which forms the main body outer peripheral surface 213 and the cover inner peripheral surface 251 in a taper shape (taper surface), and the position of the end wall 232 (cover end surface 232a) of the cover 230 along the axial direction with respect to the main body 210 are adjusted. When possible adjustment mechanisms are combined, it is preferable that the processing with the tool 10 is performed in a state where the end surface 253 on the front end side of the ring-shaped member 250 and the cover end surface 232a of the cover 230 are in contact with each other. Typically, the machining with the tool 10 is performed in a state where the tool holder is arranged along the vertical direction (including a state inclined with respect to the vertical direction) so that the tool 10 is located below.

A third embodiment of the tool holder of the present invention will be described with reference to FIGS. FIG. 8 is a cross-sectional view along the axial direction of the tool holder 300 of the third embodiment, and FIG. 9 is an enlarged view of a part IX in FIG.
The tool holder 300 according to the present embodiment is different from the ring member 150 according to the first embodiment in the configuration of the ring member 350. Other configurations are the same as those of the first embodiment. 8 and 9, except for the ring-shaped member 350, the same reference numerals as those shown in FIG. Elements indicate the same thing. Therefore, only the ring-shaped member 350 will be described below.

In the present embodiment, the ring-shaped member 350 is composed of a plurality of divided ring-shaped members 350a to 350e arranged along the axial direction. The split ring-shaped members 350a to 350e have ring inner peripheral surfaces 351a to 351e on the inner side and ring outer peripheral surfaces 352a to 352e on the outer side. A ring inner peripheral surface 351 of the ring member 350 is formed by the ring inner peripheral surfaces 351a to 351e of the plurality of divided ring members 350a to 350e, and a ring outer peripheral surface 352 of the ring member 350 is formed by the ring outer peripheral surfaces 352a to 352e. The Further, the end surface 353 on the front end side along the axial direction of the ring-shaped member 350 is formed by the end surface on the front end side along the axial direction of the divided ring-shaped portion 350a arranged on the front end side along the axial direction. Along the axial direction of the ring-shaped member 350, the split ring-shaped portion 350e disposed on the opposite side of the distal end side along the axial direction has an end surface opposite to the distal end side along the axial direction. The inner surfaces La to Le of the ring inner peripheral surfaces 351a to 351e on which the end surface 354 opposite to the tip side is formed are not set to the same value. In the present embodiment, as shown in FIG. 8, the inner diameters La to Le of the ring inner peripheral surfaces 351a to 351e are set to different values. The inner diameters La to Le of the ring inner peripheral surfaces 351a to 351e are set so that the vibration suppressing effect is enhanced.
The outer diameters of the ring outer peripheral surfaces 352a to 352e of the ring-shaped members 350a to 350e are in the radial direction between the ring outer peripheral surfaces 352a to 352e of the divided ring-shaped members 350a to 350e and the cover inner peripheral surface 331a of the cover 330. The maximum values of the intervals Ta to Te along the distance Sa to Se along the radial direction between the ring inner peripheral surfaces 351 a to 351 e of the divided ring-shaped members 350 a to 350 e and the main body outer peripheral surface 313 of the main body 310 are set. It becomes larger than the maximum value ([Ta> Sa], [Tb> Sb], [Tc> Sc], [Td> Sd], [Te> Se] are satisfied).
Since the inner diameters La to Le of the ring inner peripheral surfaces 351a to 351e of the split ring members 350a to 350e are set to different values, the main body outer peripheral surface 313 of the main body 310 and the split ring member 350a when vibrations occur. The contact timing with the inner circumferential surfaces 351a to 351e of .about.350e is different. Thereby, even when the amplitude of vibration is different, the vibration can be effectively suppressed.

In the above embodiment, a buffering mechanism that provides resistance to the movement of the ring-shaped elastic member can also be provided. By providing the buffer mechanism, the vibration energy is absorbed by the resistance to the movement of the ring-shaped member.
Examples of the buffer mechanism include a buffer mechanism that injects a liquid such as oil or water into the space and applies resistance to the movement of the ring-shaped member using the viscous resistance of the liquid, or an elastic force of an elastic member such as a spring. It is possible to use a buffer mechanism or the like that imparts resistance to the movement of the ring-shaped member by using.

The present invention is not limited to the configuration described in the embodiment, and various changes, additions, and deletions are possible.
In the embodiment, the ring-shaped member is disposed on the distal end side of the main body (holding portion), but the arrangement position of the ring-shaped member can be appropriately set according to the vibration suppressing effect or the like.
The shape and number of ring-shaped members can be changed as appropriate.
The holding unit that holds the tool is not limited to the holding unit described in the embodiment, and holding units having various configurations can be used.
The shape of the outer peripheral surface of the holding portion (main body portion) that forms the space portion that accommodates the ring-shaped member and the shape of the ring-shaped member is not limited to the shape described in the embodiment.
In the embodiment, the space portion that accommodates the ring-shaped member is formed by the outer peripheral surface and the step surface of the holding portion (main body portion) and the cover, but the method of forming the space portion is not limited to this. Furthermore, the cover can be omitted. In this case, a member that replaces the end wall of the ring-shaped member is used as the adjustment member (adjustment surface) of the adjustment mechanism.
The ring-shaped member preferably has a shape closed along the circumferential direction when viewed in a cross section perpendicular to the axial direction, but is partially cut away along the circumferential direction (for example, C-shaped). Shape).
As the ring-shaped member, one ring-shaped member or a plurality of divided ring-shaped members may be used. When using a plurality of divided ring-shaped members, a plurality of divided ring-shaped members having the same shape may be used, or a plurality of divided ring-shaped members in which at least one divided ring-shaped member is different from other divided ring-shaped members. May be used. When a plurality of divided ring-shaped members having different shapes are used, it is preferable to use divided ring-shaped members having different intervals (inner diameters) between ring inner peripheral surfaces.
One ring-shaped member or a plurality of divided ring-shaped members are accommodated in one space, but a plurality of spaces may be provided. In this case, one space member or a plurality of divided ring members are accommodated in each space.
In the embodiment, the holding portion is formed of steel and the ring-shaped member is formed of a super hard alloy. However, the holding portion and the ring-shaped member can be formed of other materials.
Each structure demonstrated by embodiment can also be used individually, and can also be used combining the some selected suitably.

10 Tool 11 Tool shank part 100, 200, 300 Tool holder 110, 210, 310 Main body part 111, 211, 311 Body peripheral surface 112, 212, 312 Hollow part 113, 213, 313 Main body outer peripheral surface 114, 214, 314 Step Surface 115, 215, 315 Female thread 120, 220, 320 Grip part 121, 221, 321 Grip surface 122, 222, 322 Tool insertion space 130, 230, 330 Cover 131, 231, 331 Outer peripheral wall 131a, 231a, 321a Inside cover Peripheral surfaces 132, 232, 332 End walls 132a, 232a, 332a Cover end surfaces 133, 233, 333 Male threads 140, 240, 340 Space portions 141, 241, 341 Inner space portions 142, 242, 342 Outer space portions 150, 250, 350 Ring-shaped members 151, 251 , 351 Ring inner peripheral surfaces 152, 252 and 352 Ring outer peripheral surfaces 153, 154, 253, 254, 353, 354 End surfaces 350a, 350b, 350c, 350d, 350e Split ring-shaped members

Claims (8)

A tool holder having a tool insertion space on the inside and a holding part configured to be able to grip a tool inserted into the tool insertion space,
It has a vibration control mechanism that suppresses vibration,
The vibration control mechanism has a ring-shaped member that is disposed outside the holding portion and integrally formed in the circumferential direction,
A clearance is formed between the inner side of the ring-shaped member and the outer side of the holding portion, and the ring-shaped member is configured to be movable relative to the holding portion. Feature tool holder. The tool holder according to claim 1,
A cover that is disposed outside the holding portion and covers an outer side of the holding portion along a circumferential direction;
A space portion is formed by the outside side of the holding portion and the inside side of the cover, and the ring-shaped member is disposed in the space portion,
A tool holder configured such that an outer side of the ring-shaped member does not contact an inner side of the cover. The tool holder according to claim 1 or 2,
The ring-shaped member is formed of a material having a specific gravity greater than that of the material forming the holding portion. The tool holder according to any one of claims 1 to 3,
The ring-shaped member has a plurality of divided ring-shaped members arranged along the axial direction. The tool holder according to claim 4,
The maximum value of the clearance between the inner side of at least one of the plurality of divided ring-shaped members and the outer side of the holding portion is the inner side of the other divided ring-shaped member and the holding portion. A tool holder characterized by being different from the maximum clearance between the outer side of the tool and the tool. The tool holder according to any one of claims 1 to 5,
The inner side of the ring-shaped member is formed in a taper shape in which the interval along the radial direction decreases sequentially toward the distal end side, and the outer side of the holding portion has an interval along the radial direction toward the distal end side. A tool holder, wherein the tool holder is formed in a tapered shape that gradually decreases. The tool holder according to any one of claims 1 to 6,
A tool holder comprising an adjusting mechanism capable of adjusting a relative movement range of the ring-shaped member along the axial direction with respect to the holding portion. The tool holder according to any one of claims 1 to 7,
A tool holder having a buffering mechanism for imparting resistance to relative movement of the ring-shaped member with respect to the holding portion.

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