JP7580583B2 - Anti-vibration tool holder and manufacturing method thereof - Google Patents

Description

The present invention relates to an anti-vibration tool holder and a method for manufacturing the same.

Conventionally, vibration-proof tool holders that are detachably attached to the spindle of a processing machine such as a machining center and hold a tool are known.

Japanese Patent No. 6079682 (Patent Document 1) discloses an anti-vibration tool holder with a built-in dynamic absorber for suppressing chatter vibration. The dynamic absorber has a vibrating body, a cylindrical vibration attenuator surrounding the vibrating body, a support that supports one end of the vibration pair, and a restricting member that restricts rotation around the axis of the support.

Patent No. 6079682

However, in the vibration-proof tool holder described in Patent Document 1, the components that make up the dynamic absorber are configured separately from each other and from the other components that make up the tool body. Therefore, in the vibration-proof tool holder described in Patent Document 1, the connection relationship between the dynamic absorber and the other components (e.g., the base material) is complex, making it difficult to suppress the decrease in rigidity that accompanies the inclusion of the dynamic absorber.

The primary object of the present disclosure is to provide an anti-vibration tool holder that is equipped with a vibration damping body while suppressing the reduction in rigidity that accompanies the inclusion of the vibration damping body.

The vibration-proof tool holder according to the present disclosure has an axis and is rotated about the axis by the spindle of a processing machine. The vibration-proof tool holder according to the present disclosure comprises a substrate including a shank portion attached to the spindle and an arbor portion for gripping a tool, and at least one vibration damping body disposed inside at least one of the shank portion and the arbor portion of the substrate. The material constituting the substrate includes a first metal. The material constituting the at least one vibration damping body includes a second metal different from the first metal. An intermetallic compound layer including a compound of the first metal and the second metal is formed at the interface between the substrate and the at least one vibration damping body.

The manufacturing method of the vibration-proof tool holder according to the present disclosure is a manufacturing method of a vibration-proof tool holder that is rotated about an axis by the spindle of a processing machine. The manufacturing method of the vibration-proof tool holder according to the present disclosure includes a step of forming an vibration-proof tool holder including a base material and at least one vibration damping body disposed inside the base material by a metal additive manufacturing method. The forming step includes a first step of melting and solidifying a material constituting the base material by the metal additive manufacturing method, and a second step of melting and solidifying a material constituting the at least one vibration damping body by the metal additive manufacturing method.

According to the present disclosure, it is possible to provide an anti-vibration tool holder that is equipped with a vibration damping body while suppressing the reduction in rigidity that accompanies the inclusion of the vibration damping body.

1 is a perspective view showing a vibration-proof tool holder according to a first embodiment; FIG. 2 is a side view of the vibration-proof tool holder shown in FIG. 1 . 3 is a cross-sectional view taken along the line III-III in FIG. 2. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3. FIG. 5 is a partially enlarged cross-sectional view for explaining an interface between a base material and a vibration damping body of the vibration-proof tool holder shown in FIGS. 1 to 4. 4 is a flowchart showing an example of a method for manufacturing the vibration-proof tool holder according to the first embodiment. 5A to 5C are diagrams for explaining an example of an additive manufacturing process of the manufacturing method of the vibration-proof tool holder according to the first embodiment. 10A to 10C are views for explaining another example of the additive manufacturing process of the manufacturing method of the vibration-proof tool holder according to the first embodiment. FIG. 9 is a diagram for explaining a first step in another example of the additive manufacturing process shown in FIG. 8 . 10 is a diagram for explaining a second step after the first step shown in FIG. 9 in another example of the additive manufacturing process shown in FIG. 8 . FIG. 1 is a cross-sectional view for explaining an example of use of the vibration-proof tool holder according to the first embodiment. FIG. 10 is a partially enlarged cross-sectional view for illustrating an interface between a base material and a vibration damping body of a vibration-proof tool holder according to a second embodiment. FIG. 11A to 11C are diagrams for explaining a modified example of the method for manufacturing the vibration-proof tool holder according to the first or second embodiment. FIG. 11 is a cross-sectional view showing a first modified example of the vibration-proof tool holder according to the first or second embodiment. FIG. 11 is a cross-sectional view showing a second modified example of the vibration-proof tool holder according to the first or second embodiment. FIG. 11 is a cross-sectional view showing a third modified example of the vibration-proof tool holder according to the first or second embodiment. FIG. 11 is a cross-sectional view showing a fourth modified example of the vibration-proof tool holder according to the first or second embodiment. FIG. 11 is a cross-sectional view showing a fifth modified example of the vibration-proof tool holder according to the first or second embodiment. FIG. 13 is a cross-sectional view showing a sixth modified example of the vibration-proof tool holder according to the first or second embodiment. FIG. 13 is a cross-sectional view showing a seventh modified example of the vibration-proof tool holder according to the first or second embodiment. 13 is a flowchart illustrating a process for casting the vibration-proof tool holder as an example of a method for manufacturing the vibration-proof tool holder of the seventh modified example. 13 is a partially enlarged cross-sectional view for illustrating an interface between a base material and a vibration damping body of a vibration-proof tool holder according to a third embodiment. FIG. FIG. 11 is a partially enlarged cross-sectional view illustrating an interface between a base material and a vibration damping body in a modified example of the vibration-proof tool holder according to the third embodiment.

Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Note that in the following drawings, the same or corresponding parts are given the same reference numbers and their description will not be repeated.

Embodiment 1.
The vibration-proof tool holder 10 according to the first embodiment shown in Fig. 1 to Fig. 4 is a tool holder that is attached to a spindle of a processing machine such as a milling cutter or an end mill and that holds a tool. The vibration-proof tool holder 10 has an axis C (see Fig. 1 to Fig. 4) and is rotated around the axis C by the spindle. The axis C of the vibration-proof tool holder is parallel to each of the axis of the spindle and the axis of the tool. When viewed from the extension direction of the axis C of the vibration-proof tool holder, the axis C of the vibration-proof tool holder is arranged so as to overlap, for example, with each of the axis of the spindle and the axis of the tool. In other words, the axis C of the vibration-proof tool holder is arranged coaxially with, for example, each of the axis of the spindle and the axis of the tool.

As shown in Figures 1 to 3, the vibration-proof tool holder 10 according to embodiment 1 mainly comprises a base material 11. The base material 11 is constructed as a single member. The base material 11 includes a shank portion 1 that is attached to the spindle of the processing machine, and an arbor portion 2 that grips the tool. In other words, a part of the base material 11 forms the shank portion 1 that is attached to the spindle of the processing machine, and another part of the base material 11 forms the arbor portion 2 that grips the tool. The arbor portion 2 is arranged alongside the shank portion 1 in the extension direction of the axis C.

The shank portion 1 is detachable from the spindle. The shank portion 1 includes, for example, an inclined portion 1A and a flange portion 1B. The inclined portion 1A has an inclined surface that is inclined so that the circumferential length (creeping distance) relative to the axis C decreases as the inclined portion 1A moves away from the arbor portion 2 in the direction of extension of the axis C. The inclined surface is provided so as to be in contact with the spindle of the processing machine. The flange portion 1B is disposed between the inclined portion 1A and the arbor portion 2 in the direction of extension of the axis C, and protrudes outward from the inclined portion 1A in the radial direction relative to the axis C. When the shank portion 1 is attached to the spindle, the inclined portion 1A is disposed in line with the spindle at least in the radial direction relative to the axis C, and the flange portion 1B is disposed in line with the spindle at least in the direction of extension of the axis.

The substrate 11 has a storage section 3 that stores a part of a tool. The storage section 3 opens at one end of the substrate 11 in the extension direction of the axis C. The storage section 3 is provided so that the axis of the tool stored in the storage section 3 is arranged coaxially with the axis C of the vibration-proof tool holder 10. The arbor section 2 is provided in a cylindrical shape so as to surround the storage section 3 in the radial direction relative to the axis C. The arbor section 2 is provided in a cylindrical shape, for example, centered on the axis C.

The substrate 11 has a contact surface that contacts the spindle in the shank portion 1. The contact surface that contacts the spindle is constituted by the substrate 11. The substrate 11 has a contact surface that contacts the tool in the arbor portion 2. The contact surface that contacts the tool is constituted by the substrate 11. From a different perspective, each of the multiple vibration damping bodies 12 is not exposed on the contact surface that contacts the spindle or the tool.

The base material 11 further has a through hole 4 formed therein, for example, so as to be connected to the storage section 3 in the direction in which the axis extends.

2 and 3, the vibration-proof tool holder 10 further includes a plurality of vibration damping bodies 12. Each of the plurality of vibration damping bodies 12 is disposed inside the base material 11. The plurality of vibration damping bodies 12 includes, for example, a vibration damping body 12 disposed inside the shank portion 1 and a vibration damping body 12 disposed inside the arbor portion 2. Each of the plurality of vibration damping bodies 12 is configured as a separate member from the other. Each of the plurality of vibration damping bodies 12 is configured as a separate member from the base material 11. Each of the plurality of vibration damping bodies 12 is embedded inside the base material 11.

The multiple vibration damping bodies 12 include, for example, a first vibration damping body 5, a second vibration damping body 6, a third vibration damping body 7, a fourth vibration damping body 8, and a fifth vibration damping body 9. The first vibration damping body 5, the second vibration damping body 6, and the third vibration damping body 7 are disposed inside the arbor portion 2. The fourth vibration damping body 8 and the fifth vibration damping body 9 are disposed inside the shank portion 1.

In a cross section perpendicular to the axis C, each of the multiple vibration damping bodies 12 is arranged to surround the axis C. As shown in Figure 4, the second vibration damping body 6 is arranged to surround the axis C. The second vibration damping body 6 is an annular member.

Like the second vibration damping body 6, the first vibration damping body 5, the third vibration damping body 7, the fourth vibration damping body 8, and the fifth vibration damping body 9 are also annular members. Each of the multiple vibration damping bodies 12 is arranged so that the central axis of each of the multiple vibration damping bodies 12 overlaps with the axis C of the vibration-proof tool holder 10.

The first vibration damping body 5 and the second vibration damping body 6 are arranged side by side at a distance from each other in the extension direction of the axis C. The second vibration damping body 6 is arranged on the shank portion 1 side relative to the first vibration damping body 5 in the extension direction of the axis C. The entire first vibration damping body 5 and a portion of the second vibration damping body 6 in the extension direction of the axis C are arranged at a distance from the accommodating portion 3 in the radial direction relative to the axis C, and further outboard than the accommodating portion 3. The entire first vibration damping body 5 and a portion of the second vibration damping body 6 in the extension direction of the axis C surround the accommodating portion 3.

The remainder of the second vibration damping body 6 in the extension direction of the axis C is spaced apart from the third vibration damping body 7 in the radial direction relative to the axis C and is positioned further outboard than the third vibration damping body 7. The remainder of the second vibration damping body 6 in the extension direction of the axis C surrounds the third vibration damping body 7.

The third vibration damping body 7 is spaced apart from the accommodating portion 3 in the direction of extension of the axis C, and is disposed on the shank portion 1 side of the accommodating portion 3. The third vibration damping body 7 is spaced apart from the through hole 4 in the radial direction relative to the axis C, and is disposed outside the through hole 4.

The fourth vibration damping body 8 is disposed inside the inclined portion 1A. The fourth vibration damping body 8 is disposed along the inclined surface of the inclined portion 1A. The fourth vibration damping body 8 is disposed at a distance from each of the accommodating portion 3 and the second vibration damping body 6 in the extension direction of the axis C.

The fifth vibration damping body 9 is disposed inside the flange portion 1B. The fifth vibration damping body 9 is disposed between the second vibration damping body 6 and the fourth vibration damping body 8 in the extension direction of the axis C. The fifth vibration damping body 9 is disposed outward of the fourth vibration damping body 8 in the radial direction relative to the axis C.

The material constituting the substrate 11 includes a first metal. The first metal is composed of any metal element contained in the material constituting the substrate 11. The rigidity of the material constituting the substrate 11 is higher than the rigidity of the material constituting each of the multiple vibration damping bodies 12.

The material constituting the substrate 11 includes, for example, at least one selected from a first group consisting of carbon steel, chromium molybdenum steel, nickel chromium molybdenum steel, stainless steel, and cemented carbide. The chromium molybdenum steel and the nickel chromium molybdenum steel may be any chromium molybdenum steel and nickel chromium molybdenum steel defined in the JIS standard (JIS G 4053:2016). An example of the chromium molybdenum steel is SCM435. The first metal is, for example, iron (Fe) or chromium (Cr).

The material constituting each of the multiple vibration attenuators 12 includes a second metal different from the first metal. The second metal is made of any metal element contained in the material constituting each of the multiple vibration attenuators 12. The material constituting each of the multiple vibration attenuators 12 includes at least one selected from a second group consisting of, for example, magnesium alloys, aluminum alloys, and cemented carbide alloys. The second metal is, for example, magnesium (Mg) or aluminum (Al).

As shown in FIG. 5, an intermetallic compound layer 13 is formed at the interface between the substrate 11 and each of the multiple vibration attenuators 12. The intermetallic compound layer 13 includes a compound of a first metal and a second metal. In other words, each of the multiple vibration attenuators 12 is metallically bonded to the substrate 11. The intermetallic compound layer 13 is formed on the entire interface between the substrate 11 and each of the multiple vibration attenuators 12. In other words, the intermetallic compound layer 13 is formed on the entire surface of each of the multiple vibration attenuators 12. The thickness of the intermetallic compound layer 13 is smaller than the minimum width of each of the multiple vibration attenuators 12 (for example, the radial width with respect to the axis C in the case of the second metal). The thickness of the intermetallic compound layer 13 is, for example, 1 μm or more and 1 mm or less.

<Method of manufacturing anti-vibration tool holder>
As shown in Figure 6, the manufacturing method of the vibration-proof tool holder 10 includes a step (S1) of forming the vibration-proof tool holder 10, which includes a base material 11 and each of a plurality of vibration damping bodies 12, by a metal additive manufacturing method, and a step (S2) of performing shaping processing on the vibration-proof tool holder 10.

Metal additive manufacturing is an additive manufacturing method using metal materials. Additive manufacturing methods include, for example, Directed Energy Deposition (DED) or Powder Bed Fusion (PBF).

In step (S1), first, shape data representing the shape of the vibration-proof tool holder 10 is divided into a plurality of layers stacked in the extension direction of the axis C, thereby preparing shape data for each of the plurality of layers. The shape data representing the shape of the vibration-proof tool holder 10 may be divided into a plurality of layers stacked in a direction different from the extension direction of the axis C. Next, a plurality of layered objects are continuously formed based on the shape data for each of the plurality of layers. Each of the plurality of layered objects includes at least one of a model made of the material constituting the base material 11 and a model made of the material constituting each of the plurality of vibration damping bodies 12. In this way, the vibration-proof tool holder 10 is formed by integrally stacking a plurality of layered objects.

7 is a diagram for explaining step (S1) when the DED method is adopted as the metal additive manufacturing method. In the DED method, an additive manufacturing device is used that includes a base plate 200, a supply unit 201 that supplies the raw material M for modeling to the region R to be modeled on the base plate 200, and a light source 202 that irradiates the region R with a high-energy electron beam or laser L.

The supply unit 201 and the light source 202 are capable of changing their relative positions with respect to the base plate 200. The supply unit 201 includes a first supply unit that supplies raw materials for forming the substrate 11, and a second supply unit that supplies raw materials for forming each of the multiple vibration damping bodies 12. The supply unit 201 is provided to supply, for example, each wire-shaped raw material to the region R. The supply unit 201 may also be provided to supply each powder-shaped raw material to the region R.

In step (S1), the light source 202 irradiates the region R where the substrate 11 is to be formed with a laser L while the supply unit 201 supplies the raw material M for forming the substrate 11 to the region R based on the shape data of each layer. The energy of the laser L is set so as to melt the raw material M for forming the substrate 11. Furthermore, the supply unit 201 and the light source 202 are scanned relative to the base plate 200 so that the region R moves continuously within the same layer. The light source 202 irradiates the region where each of the multiple vibration dampers 12 is to be formed with a laser L while the supply unit 201 supplies the raw material for forming each of the multiple vibration dampers 12. The energy of the laser L is set so as to melt the raw material for forming each of the multiple vibration dampers 12. As a result, each raw material supplied to each region melts and then solidifies, thereby obtaining each layered object. After that, the supply unit 201 and the light source 202 move relatively to the base plate 200 by an amount corresponding to the thickness of one layer of the layered object. Then, the above-mentioned scanning is repeated again. If there is another layered object that was previously formed immediately below the layered object, the raw material supplied to the region R and a part of the layered object located immediately below the region R melt and then solidify. As a result, a three-dimensional object O is obtained in which a plurality of layered objects are three-dimensionally stacked.

By the above-mentioned DED method, an intermetallic compound layer 13 is formed at the interface between the substrate 11 and each of the multiple vibration damping bodies 12 in each layered structure or between multiple layered structures adjacent in the stacking direction.

8 to 10 are diagrams for explaining step (S1) when the PBF method is adopted as the metal additive manufacturing method. As shown in Figs. 8 to 10, the PBF method uses an additive manufacturing device including a base plate 300, a supply unit 301 for forming a powder bed PB by spreading raw material M for modeling in layers on the base plate 300, a light source 302 for irradiating a high-energy electron beam or laser L onto an area of the powder bed PB to be modeled, and a drive unit 303 for moving the base plate 300 relative to the supply unit 301.

The supply unit 301 includes a powder hopper 301A, a modeling stage 301B, and a squeeze 301C. The modeling stage 301B has a cylindrical portion extending in the vertical direction and a flange portion extending outward from the upper end of the cylindrical portion. The base plate 300 and the drive unit 303 are arranged to move in the vertical direction inside the cylindrical portion. The powder hopper 301A supplies powdered raw material M onto the base plate 300 and the modeling stage 301B. The powder hopper 301A includes a first powder hopper that supplies raw material for forming the base material 11, and a second powder hopper that supplies raw material for forming each of the multiple vibration damping bodies 12.

The squeezer 301C flattens the powdered raw material supplied by the powder hopper 301A onto the base plate 300 and the modeling stage 301B. The supply unit 301 forms a powder bed PB on the base plate 300.

In step (S1), the light source 302 irradiates the laser L to the area of the powder bed PB made of the raw material for forming the substrate 11, where the substrate 11 is to be formed, based on the shape data of each layer. Furthermore, the light source 302 is scanned relative to the base plate 300 so that the area moves continuously within the same layer. As a result, a layered object of one layer of the substrate 11 is formed. Next, the base plate 300 moves upward relative to the forming stage 301B by the thickness of the layered object of one layer. As a result, the layered object of one layer of the substrate 11 and the area where the vibration damping body 12 is to be formed are placed on the upper surface of the powder bed PB made of the raw material for forming the substrate 11.

Next, the supply unit 301 forms a powder bed made of raw materials for forming the vibration attenuator 12 on the upper surface of the powder bed PB made of raw materials for forming the substrate 11. Next, the light source 302 irradiates the laser L to the area where the vibration attenuator 12 is to be formed in the powder bed made of raw materials for forming each of the vibration attenuators 12. Furthermore, the light source 302 is scanned relative to the base plate 300 so that the area moves continuously within the same layer. As a result, a layered object of one layer of each vibration attenuator 12 is formed so as to constitute a single layered object together with the layered object of the substrate 11. Then, as shown in FIG. 10, the base plate 300 moves downward relative to the forming stage 301B by the thickness of the layered object of the one layer. Then, the above scanning is repeated again.

By the above-mentioned PBF method, an intermetallic compound layer 13 is formed at the interface between the substrate 11 and each of the multiple vibration damping bodies 12 in each layered structure or between multiple layered structures adjacent in the stacking direction.

After the above step (S1), a step (S2) is carried out to shape the vibration-proof tool holder 10. The shape-forming step (S2) may be carried out as necessary, but does not have to be carried out.

<Effects of anti-vibration tool holder>
In the vibration-proof tool holder 10, an intermetallic compound layer 13 is formed at the interface between the substrate 11 and each of the multiple vibration damping bodies 12. That is, each of the multiple vibration damping bodies 12 is metallically bonded to the substrate 11. In the vibration-proof tool holder 10, each of the multiple vibration damping bodies 12 is metallically bonded to the substrate 11, so that the decrease in rigidity caused by the provision of the multiple vibration damping bodies 12 is suppressed compared to a vibration-proof tool holder in which the vibration damping body is not metallically bonded to the substrate (hereinafter referred to as a vibration-proof tool holder of a comparative example). Furthermore, in the vibration-proof tool holder 10, chatter vibration during machining can be damped by the multiple vibration damping bodies 12, so that the decrease in machining accuracy is suppressed.

In addition, the vibration-proof tool holder 10 has improved rigidity as described above without increasing weight compared to the vibration-proof tool holder of the comparative example. Therefore, the vibration-proof tool holder 10 can achieve weight reduction without decreasing rigidity compared to the vibration-proof tool holder of the comparative example.

Furthermore, when the vibration-proof tool holder 10 and the vibration-proof tool holder of the comparative example are used under the same conditions, wear of each of the multiple vibration damping bodies 12 can be suppressed in the vibration-proof tool holder 10 compared to the vibration-proof tool holder of the comparative example. In the vibration-proof tool holder of the comparative example, when chatter vibration occurs, the base material and each of the vibration damping bodies vibrate in different modes as different members, so the vibration damping bodies are prone to wear. In contrast, in the vibration-proof tool holder 10, when chatter vibration occurs, the base material 11 and each of the multiple vibration damping bodies 12 can vibrate as a unit, so the vibration damping bodies are less likely to wear out compared to the vibration-proof tool holder of the comparative example.

In addition, when at least a portion of the multiple vibration damping bodies 12 is exposed on the surface of the base material 11, the portion may be worn down with use. In contrast, in the vibration-proof tool holder 10, each of the multiple vibration damping bodies 12 is embedded inside the base material 11, and an intermetallic compound layer 13 is formed on the entire surface of each of the multiple vibration damping bodies 12. Therefore, in the vibration-proof tool holder 10, each of the multiple vibration damping bodies 12 is less likely to be worn down compared to when at least a portion of the multiple vibration damping bodies 12 is exposed on the surface of the base material 11.

In the vibration-proof tool holder 10, the base material 11 is constructed as a single member. Therefore, the rigidity of the vibration-proof tool holder 10 is higher than the rigidity of a vibration-proof tool holder in which the base material 11 is constructed as an assembly of multiple members.

The material constituting the base material 11 includes at least one selected from a first group consisting of carbon steel, chromium molybdenum steel, nickel chromium molybdenum steel, and cemented carbide. In such an anti-vibration tool holder 10, a relatively high rigidity is achieved.

As shown in Figure 11, the vibration-proof tool holder 10 holds the tool 20. The vibration-proof tool holder 10 is attached to the spindle 30 of a processing machine. The axis C of the vibration-proof tool holder 10 is arranged coaxially with the axis of the tool 20 and the axis of the spindle 30.

Each of the multiple vibration damping bodies 12 is arranged to surround the axis C. In particular, the first vibration damping body 5 and the second vibration damping body 6 are arranged to be aligned radially with the accommodating section 3 and the tool 20 relative to the axis C. The first vibration damping body 5 and the second vibration damping body 6 can effectively damp chatter vibrations of the tool 20 in the radial direction relative to the axis C. The vibration-proof tool holder 10 including the first vibration damping body 5 and the second vibration damping body 6 is suitable for a tool holder that holds a tool such as a milling cutter or end mill in which vibrations in the radial direction relative to the axis C are dominant.

The third vibration damping body 7 is arranged to be aligned with the storage section 3 and the tool 20 in the extension direction of the axis C. The third vibration damping body 7 can effectively damp chatter vibrations of the tool 20 in the extension direction of the axis C. The vibration-proof tool holder 10 equipped with the third vibration damping body 7 is suitable for a tool holder that holds a tool such as a drill in which vibrations in the extension direction of the axis C are dominant. The vibration-proof tool holder 10 equipped with the third vibration damping body 7 is also suitable for a tool holder that holds a tool such as a milling cutter or end mill that has a relatively large twist angle.

The fourth vibration damping body 8 is disposed inside an inclined portion 1A (first portion) of the base material 11, which is in contact with the spindle 30 and disposed alongside the spindle 30 in the radial direction relative to the axis C. The fourth vibration damping body 8 effectively suppresses the transmission of chatter vibrations of the tool 20 in the radial direction relative to the axis C to the spindle 30.

The fifth vibration damping body 9 is disposed inside the flange portion 1B (second portion) of the base material 11, which is in contact with the spindle 30 and is disposed alongside the spindle 30 in the extension direction of the axis C. The fifth vibration damping body 9 effectively suppresses the transmission of chatter vibrations of the tool 20 in the extension direction of the axis C to the spindle 30.

The base material 11 has a contact surface in the shank portion 1 that contacts the spindle, and a contact surface in the arbor portion 2 that contacts the tool. Compared to when each of the multiple vibration damping bodies 12 is exposed on a contact surface that contacts the spindle or the tool, wear of each of the multiple vibration damping bodies 12 is suppressed.

Embodiment 2.
The vibration-proof tool holder according to the second embodiment basically has the same configuration as the vibration-proof tool holder 10 according to the first embodiment, but differs from the vibration-proof tool holder 10 in that the substrate 11 includes a plurality of first substrates 11A and second substrates 11B, as shown in Fig. 12. The following mainly describes the differences from the vibration-proof tool holder 10.

Each of the multiple first substrates 11A is arranged to surround each of the multiple vibration damping bodies 12. From a different perspective, each of the multiple first substrates 11A is provided to surround a corresponding one of the multiple vibration damping bodies 12. The thermal expansion coefficient of the material constituting the first substrate 11A is greater than the thermal expansion coefficient of the material constituting the second substrate 11B and is smaller than the thermal expansion coefficient of the material constituting each of the multiple vibration damping bodies 12.

The material constituting the first substrate 11A includes, for example, at least one of a copper alloy and an aluminum alloy. The first metal is a metal contained in the material constituting the first substrate 11A. The material constituting the first substrate 11A further includes a third metal different from the first metal.

An intermetallic compound layer 13 is formed at the interface between each of the multiple vibration damping bodies 12 and each of the multiple corresponding first substrates 11A. The intermetallic compound layer 13 includes a compound of a first metal contained in the material constituting the first substrate 11A and a second metal contained in the material constituting each of the multiple vibration damping bodies 12.

The material constituting the second substrate 11B includes at least one selected from a first group consisting of carbon steel, chromium-molybdenum steel, nickel-chromium-molybdenum steel, and cemented carbide. The material constituting the second substrate 11B includes a fourth metal different from the first metal or the third metal.

At the interface between each of the multiple first substrates 11A and the second substrate 11B, for example, an intermetallic compound layer 14 is formed. The intermetallic compound layer 14 contains a compound of a first metal or a third metal contained in the material constituting the first substrate 11A and a fourth metal contained in the material constituting the second substrate 11B. The intermetallic compound layer 14 is formed, for example, on the entire surface of the first substrate 11A.

The manufacturing method of the vibration-proof tool holder according to the second embodiment differs from the manufacturing method of the vibration-proof tool holder 10 in that one layer of each vibration attenuator 12 is formed continuously with one layer of each of the first substrate 11A and the second substrate 11B. By the above-mentioned DED method or PBF method, an intermetallic compound layer 13 and an intermetallic compound layer 14 are formed in each layer or between multiple layered objects adjacent to each other in the stacking direction.

In the vibration-proof tool holder according to the second embodiment, a first substrate 11A is disposed between each of the plurality of vibration damping bodies 12 and a second substrate 11B, and the thermal expansion coefficient of the material constituting the first substrate 11A is greater than the thermal expansion coefficient of the material constituting the second substrate 11B and is less than the thermal expansion coefficient of the material constituting each of the plurality of vibration damping bodies 12. Therefore, the residual stress of the vibration-proof tool holder according to the second embodiment can be reduced compared to the residual stress of the vibration-proof tool holder 10.

Specifically, in the vibration-proof tool holder according to the second embodiment, the difference between the thermal expansion coefficient of the material constituting the first substrate 11A and the thermal expansion coefficient of the material constituting each of the plurality of vibration damping bodies 12 is smaller than the difference between the thermal expansion coefficient of the material constituting the substrate 11 and the material constituting each of the plurality of vibration damping bodies 12 in the vibration-proof tool holder 10. Therefore, in the process in which each of the raw materials melted in the additive manufacturing process of the above-mentioned manufacturing method solidifies, the difference between the contraction rate of the first substrate 11A and the contraction rate of the vibration damping body 12 is smaller than the difference between the contraction rate of the substrate 11 of the vibration-proof tool holder 10 and the contraction rate of the vibration damping body 12. As a result, in the vibration-proof tool holder according to the second embodiment, the decrease in strength caused by residual stress is suppressed compared to the vibration-proof tool holder 10.

Embodiment 3.
The vibration-proof tool holder according to embodiment 3 basically has the same configuration as the vibration-proof tool holder 10 according to embodiment 1, but differs from the vibration-proof tool holder 10 in that the substrate 11 includes a third substrate 11C and a fourth substrate 11D, as shown in Fig. 22. The following mainly describes the differences from the vibration-proof tool holder 10.

As shown in Figure 22, the third substrate 11C has a surface S exposed on the surface of the substrate 11. The exposed surface S of the third substrate 11C is included in the surface that comes into contact with the spindle or the tool when the vibration-proof tool holder according to embodiment 3 is attached to the spindle of a processing machine and holds the tool. Of the surfaces of the third substrate 11C, only the exposed surface S is exposed on the surface of the substrate 11. The remainder of the surface of the third substrate 11C is not exposed on the surface of the substrate 11. The third substrate 11C is arranged, for example, to surround each of the multiple vibration damping bodies 12.

The hardness of the material constituting the third substrate 11C is harder than the hardness of the material constituting the fourth substrate 11D. Here, hardness means Vickers hardness.

The material constituting the third substrate 11C includes at least one of a third group consisting of, for example, stainless steel, alloy tool steel, high-speed tool steel, and cemented carbide. The material constituting the third substrate 11C includes a fifth metal different from the first metal.

The material constituting the fourth substrate 11D includes at least one selected from a first group consisting of carbon steel, chromium-molybdenum steel, nickel-chromium-molybdenum steel, and cemented carbide. The material constituting the fourth substrate 11D includes a sixth metal different from the fifth metal.

An intermetallic compound layer 13 is formed at the interface between the third substrate 11C and each of the multiple vibration attenuators 12. An intermetallic compound layer 15 is formed at the interface between the third substrate 11C and the fourth substrate 11D. The intermetallic compound layer 13 contains a compound of a fifth metal and a second metal contained in the multiple vibration attenuators 12. The intermetallic compound layer 15 contains a compound of the fifth metal and a sixth metal.

In the anti-vibration tool holder according to the third embodiment, the third substrates 11C have an exposed surface S that is exposed on the surface of the substrate 11 of the anti-vibration tool holder, and the hardness of the material constituting the third substrate 11C is harder than the hardness of the material constituting the fourth substrate 11D. Therefore, in the anti-vibration tool holder according to the third embodiment, wear of the substrate 11 is suppressed compared to the anti-vibration tool holder 10.

<Modification>
13, in the manufacturing methods of the vibration-proof tool holder according to the first to third embodiments, at least the peripheral region of the region R to which the laser L is irradiated when forming the layered object of the base material 11 may be cooled. For example, in the manufacturing method of the vibration-proof tool holder according to the second embodiment, at least the peripheral region of the region to which the laser L is irradiated when forming the layered object of the second base material 11B may be cooled. From a different perspective, when melting a raw material with a relatively high melting point, the peripheral region of the region to which the laser L is irradiated to melt the raw material may be cooled to below the melting point of the raw material.

The peripheral region to be cooled is a structure in the same layer as the region R irradiated with the laser L, and includes a layered structure formed by melting and then solidifying a raw material having a relatively low melting point. The peripheral region further includes, for example, a layered structure directly below the region R irradiated with the laser L, and formed by melting and then solidifying a raw material having a relatively low melting point.

The cooling is performed by at least one cooling unit 203. The cooling unit 203 is configured to inject, for example, a low-temperature heat medium A (for example, gas or liquid). The low-temperature heat medium is, for example, carbon dioxide (dry ice) or nitrogen (liquid nitrogen), but is not limited thereto.

The cooling may be performed by a plurality of cooling units 203. Each of the plurality of cooling units 203 is configured to inject a low-temperature heat medium (e.g., gas or liquid) into a peripheral region surrounding the region R. The plurality of cooling units 203 are arranged, for example, in a side view, to sandwich a fan-shaped region formed between the region R, the raw material M supplied from the supply unit 201 to the region R, and the laser L irradiated from the light source 202 to the region R.

When melting a raw material having a relatively low melting point, the area surrounding the area where the laser L is irradiated to melt the raw material may be cooled below the melting point of the raw material.

If the above cooling is not performed, the layered object formed by melting and then solidifying the raw material that is located directly below the area irradiated by the laser L and has a relatively low melting point will melt and solidify again, which may result in the shape and dimensions of the vibration-proof tool holder obtained by the above additive manufacturing process being significantly different from the designed shape and dimensions of the vibration-proof tool holder.

In response to this, by performing the above-mentioned cooling, it is possible to prevent the layered object, which is formed by melting and then solidifying a raw material that is located directly below the area irradiated by the laser L and has a relatively low melting point, from melting again.

13 shows an example in which the cooling is applied to the DED method, but the cooling can also be applied to the PBF method. In this case, the peripheral region to be cooled is a structure in the same layer as the region R irradiated with the laser L, and includes a layered structure formed by melting and then solidifying a raw material with a relatively low melting point.

In the vibration-proof tool holder according to the first to third embodiments, it is sufficient that at least one vibration damping body 12 is arranged inside at least one of the shank portion 1 and the arbor portion 2 of the base material 11. The arrangement of the at least one vibration damping body 12 can be changed as appropriate depending on, for example, the mode of chatter vibration that occurs during machining. The at least one vibration damping body 12 is arranged, for example, at least inside the arbor portion 2.

In the vibration-proof tool holder according to embodiments 1 to 3, the shape of each of the multiple vibration damping bodies 12 in a cross section perpendicular to the axis C is not limited to the shape shown in Fig. 4. The shape of each of the multiple vibration damping bodies 12 in a cross section perpendicular to the axis C may be any of the shapes shown in Figs. 14 to 19. Each of the multiple vibration damping bodies 12 may have a cross-sectional shape different from the others.

14 to 19, the vibration-proof tool holder according to embodiments 1 to 3 may include a plurality of vibration damping bodies 12 arranged at intervals from one another in the circumferential direction relative to the axis C. From a different perspective, in the vibration-proof tool holder according to embodiments 1 and 2, at least one of the first vibration damping body 5, the second vibration damping body 6, the third vibration damping body 7, the fourth vibration damping body 8, and the fifth vibration damping body 9 may be divided into a plurality of portions in the circumferential direction relative to the axis C.

As shown in Figure 14, multiple (e.g., three) vibration damping bodies 12 may be arranged at intervals from one another in the circumferential direction about the axis C. Each of the multiple vibration damping bodies 12 arranged at intervals from one another in the circumferential direction about the axis C is, for example, provided rotationally symmetrically about the axis C. The distance (spacing) between two circumferentially adjacent vibration damping bodies 12 is, for example, shorter than the circumferential length of each of the two vibration damping bodies 12.

15, a first group of vibration damping bodies 12A may be arranged at intervals on a first circle centered on the axis C, and a second group of vibration damping bodies 12B may be arranged at intervals on a second circle centered on the axis C and drawn outside the first circle. From a different perspective, at least one of the first vibration damping body 5, the second vibration damping body 6, the third vibration damping body 7, the fourth vibration damping body 8, and the fifth vibration damping body 9 may be composed of the first group of vibration damping bodies 12A and the second group of vibration damping bodies 12B.

Each of the vibration damping bodies 12A in the first group has, for example, the same shape and dimensions as each other. Each of the vibration damping bodies 12B in the second group has, for example, the same shape and dimensions as each other. Each of the vibration damping bodies 12A in the first group and each of the vibration damping bodies 12B in the second group are arranged, for example, rotationally symmetrical with respect to the axis C.

The distance between two circumferentially adjacent vibration attenuators 12A of the first group is, for example, shorter than the circumferential length of each of the two vibration attenuators 12A. The distance between two circumferentially adjacent vibration attenuators 12B of the second group is, for example, shorter than the circumferential length of each of the two vibration attenuators 12B. The distance between two circumferentially adjacent vibration attenuators 12B is, for example, longer than the distance between two circumferentially adjacent vibration attenuators 12A. The circumferential length of each vibration attenuator 12B is, for example, longer than the circumferential length of each vibration attenuator 12A.

The first group of vibration damping bodies 12A has, for example, multiple sets of vibration damping bodies 12A. Each set of vibration damping bodies 12A has two vibration damping bodies 12A arranged to face each other across the axis C. The second group of vibration damping bodies 12B has, for example, multiple sets of vibration damping bodies 12B. Each set of vibration damping bodies 12B has two vibration damping bodies 12B arranged to face each other across the axis C.

Each vibration damping body 12B has, for example, end portions arranged so as to overlap with each of two circumferentially adjacent vibration damping bodies 12A in the radial direction relative to the axis C, and a central portion arranged so as to overlap with a part of the substrate 11 located between the two vibration damping bodies 12A in the radial direction. The first group of vibration damping bodies 12A and the second group of vibration damping bodies 12B are provided so that at least one of the first group of vibration damping bodies 12A and the second group of vibration damping bodies 12B is exposed in any cross section passing through the axis C.

16, the circumferential length of each of the multiple vibration damping bodies 12 spaced apart from one another in the circumferential direction relative to the axis C may be shorter than the radial length of each of the multiple vibration damping bodies 12 relative to the axis C. The circumferential length of each of the multiple vibration damping bodies 12 spaced apart from one another in the circumferential direction relative to the axis C may be shorter than the distance between two adjacent vibration damping bodies 12 in the circumferential direction.

As shown in FIG. 17, the cross-sectional shape of each of the multiple vibration damping bodies 12 arranged at intervals from one another in the circumferential direction relative to the axis C may be circular.

As shown in FIG. 18, the cross-sectional shape of each of the multiple vibration damping bodies 12 arranged at intervals from one another in the circumferential direction about the axis C may be quadrilateral, square or rectangular.

As shown in FIG. 19, the cross-sectional shape of each of the multiple vibration damping bodies 12 arranged at intervals from one another in the circumferential direction relative to the axis C may be hexagonal.

As shown in Figure 20, in the vibration-proof tool holder according to embodiments 1 to 3, at least one vibration damping body 12 may have an exposed portion 12C that appears on the outer peripheral surface of the substrate 11. Each of the multiple vibration damping bodies 12 may have an exposed portion 12C. Such an vibration-proof tool holder may be manufactured by the additive manufacturing method described above, but may also be manufactured by casting. The manufacturing method for the vibration-proof tool holder according to this modified example comprises a step of forming, by casting, an vibration-proof tool holder including the substrate 11 and at least one vibration damping body 12.

21, the process for forming an anti-vibration tool holder by casting includes a step (S3) of casting a base material 11 having at least one hollow portion using a mold and a core, and a step (S4) of forming one vibration damping body 12 in the at least one hollow portion using the base material 11 as a mold after the core is removed. The melting point of the material constituting the vibration damping body 12 is lower than the melting point of the material constituting the base material 11. In this manner, the anti-vibration tool holder according to this modified example can also be manufactured.

In the vibration-proof tool holder according to the third embodiment, the intermetallic compound layer 13 may be formed at the interface between the fourth substrate 11D and each of the plurality of vibration damping bodies 12. For example, the vibration-proof tool holder according to the third embodiment may include a metal mixture layer 13 formed at the interface between some of the plurality of vibration damping bodies 12 and the third material 11C, and a metal mixture layer 13 formed at the interface between the remaining of the plurality of vibration damping bodies 12 and the fourth material 11D.

23, the second substrate 11B of the vibration-proof tool holder according to the second embodiment may include the third substrate 11C and the fourth substrate 11D of the vibration-proof tool holder according to the third embodiment. In this case, the vibration damping body 12, the intermetallic compound layer 13, the first substrate 11A, the intermetallic compound layer 14, the third substrate 11C, the intermetallic compound layer 15, and the fourth substrate 11D are stacked in order. In such a vibration-proof tool holder, the same effect as that of the vibration-proof tool holder according to the second embodiment can be realized, and the same effect as that of the vibration-proof tool holder according to the third embodiment can also be realized.

Although the embodiments of the present disclosure have been described above, the above-described embodiments can be modified in various ways. Furthermore, the scope of the present disclosure is not limited to the above-described embodiments. The scope of the present disclosure is defined by the claims, and is intended to include all modifications that are equivalent in meaning to and within the scope of the claims.

1 shank portion, 1A inclined portion, 1B flange portion, 2 arbor portion, 3 storage portion, 4 through hole, 5 first vibration damping body, 6 second vibration damping body, 7 third vibration damping body, 8 fourth vibration damping body, 9 fifth vibration damping body, 10 tool holder, 11 substrate, 11A first substrate, 11B second substrate, 11C third substrate, 11D fourth substrate, 12, 12A, 12B vibration damping body, 12C exposed portion, 13, 14 intermetallic compound layer, 20 tool, 30 spindle, 200, 300 base plate, 201, 301 supply portion, 202, 302 light source, 203 cooling portion, 301A powder hopper, 301B molding stage, 301C squeeze, 303 drive portion.

Claims (17)

A vibration-proof tool holder having an axis and rotated about the axis by a main shaft of a processing machine,
A base material including a shank portion attached to the spindle and an arbor portion that grips a tool;
at least one vibration damping body disposed within at least one of the shank portion and the arbor portion of the substrate;
the material constituting the substrate includes a first metal;
the material constituting the at least one vibration damping body includes a second metal different from the first metal;
an intermetallic compound layer including a compound of the first metal and the second metal is formed at an interface between the substrate and the at least one vibration attenuator;
The at least one vibration damping body is embedded inside the base material and is not exposed on the surface of the base material;
An anti-vibration tool holder , wherein the intermetallic compound layer is formed on the entire surface of the at least one vibration-damping body . The vibration-proof tool holder according to claim 1, wherein the base material is constructed as a single member. 3. The vibration-proof tool holder according to claim 2 , wherein the material constituting the base material includes at least one selected from a first group consisting of carbon steel, chromium-molybdenum steel, nickel-chromium-molybdenum steel, stainless steel, and cemented carbide. A vibration-proof tool holder having an axis and rotated about the axis by a main shaft of a processing machine,
A base material including a shank portion attached to the spindle and an arbor portion that grips a tool;
at least one vibration damping body disposed within at least one of the shank portion and the arbor portion of the substrate;
the material constituting the substrate includes a first metal;
the material constituting the at least one vibration damping body includes a second metal different from the first metal;
an intermetallic compound layer including a compound of the first metal and the second metal is formed at an interface between the substrate and the at least one vibration attenuator;
The substrate includes a first substrate arranged to surround the at least one vibration attenuator, and a second substrate arranged to surround the first substrate,
The intermetallic compound layer is formed at an interface between the first substrate and the at least one vibration damping body. 5. The vibration-proof tool holder according to claim 4, wherein the thermal expansion coefficient of the material constituting the first substrate is greater than the thermal expansion coefficient of the material constituting the second substrate and is less than the thermal expansion coefficient of the material constituting the at least one vibration damping body. a material constituting the first base material includes at least one of a copper alloy and an aluminum alloy;
The first metal is a metal contained in at least one of a copper alloy and an aluminum alloy,
6. The vibration-proof tool holder according to claim 5 , wherein the material constituting the second base material includes at least one selected from a first group consisting of carbon steel, chromium-molybdenum steel, nickel-chromium-molybdenum steel, stainless steel, and cemented carbide. A vibration-proof tool holder having an axis and rotated about the axis by a main shaft of a processing machine,
A base material including a shank portion attached to the spindle and an arbor portion that grips a tool;
at least one vibration damping body disposed within at least one of the shank portion and the arbor portion of the substrate;
the material constituting the substrate includes a first metal;
the material constituting the at least one vibration damping body includes a second metal different from the first metal;
an intermetallic compound layer including a compound of the first metal and the second metal is formed at an interface between the substrate and the at least one vibration attenuator;
The base material includes a third base material having an exposed surface exposed on a surface of the base material, and a fourth base material arranged so as to surround a surface of the third base material other than the exposed surface,
the intermetallic compound layer is formed at an interface between the third substrate or the fourth substrate and the at least one vibration damping body,
A vibration-proof tool holder, wherein the hardness of a material constituting the third base material is greater than the hardness of a material constituting the fourth base material. The second base material includes a third base material having an exposed surface exposed on a surface of the base material, and a fourth base material arranged to surround a surface of the third base material other than the exposed surface,
The vibration-proof tool holder according to claim 4 , wherein the hardness of the material constituting the third base material is greater than the hardness of the material constituting the fourth base material. The material constituting the third base material includes at least one selected from a third group consisting of stainless steel, alloy tool steel, high-speed tool steel, and cemented carbide;
8. The vibration-proof tool holder according to claim 7 , wherein the material constituting the fourth base material includes at least one selected from a first group consisting of carbon steel, chromium-molybdenum steel, nickel-chromium-molybdenum steel, stainless steel, and cemented carbide. A vibration-proof tool holder having an axis and rotated about the axis by a main shaft of a processing machine,
A base material including a shank portion attached to the spindle and an arbor portion that grips a tool;
at least one vibration damping body disposed within at least one of the shank portion and the arbor portion of the substrate;
the material constituting the substrate includes a first metal;
the material constituting the at least one vibration damping body includes a second metal different from the first metal;
an intermetallic compound layer including a compound of the first metal and the second metal is formed at an interface between the substrate and the at least one vibration attenuator;
the material constituting the at least one vibration damping body includes at least one selected from a second group consisting of a magnesium alloy, an aluminum alloy, and a cemented carbide;
A vibration-proof tool holder, wherein the second metal is at least one metal selected from the second group. The base material includes a receiving portion in which a part of the tool is received,
The vibration-proof tool holder according to any one of claims 1 to 7, wherein the at least one vibration damping body is arranged so as to be aligned with the accommodating portion in a radial direction relative to the axis. The base material includes a receiving portion in which a part of the tool is received,
The vibration-proof tool holder according to any one of claims 1 to 7, wherein the at least one vibration attenuator is arranged so as to be aligned with the accommodating portion in the direction in which the axis extends. the substrate has a contact surface that contacts the tool;
The vibration-proof tool holder according to claim 11 , wherein the contact surface is constituted by the base material. The shank portion of the base material has a first portion that is in contact with the main shaft and is arranged side by side with the main shaft in a radial direction relative to the axis line, and a second portion that is in contact with the main shaft and is arranged side by side with the main shaft in an extension direction of the axis line,
The vibration-proof tool holder according to any one of claims 1 to 7, wherein the at least one vibration damping body is arranged in at least one of the first part and the second part. An anti-vibration tool holder according to any one of claims 1 to 7, wherein, in a cross section perpendicular to the axis, the at least one vibration damping body is arranged to surround the axis. A vibration-proof tool holder having an axis and rotated about the axis by a main shaft of a processing machine,
A base material including a shank portion attached to the spindle and an arbor portion that grips a tool;
at least one vibration damping body disposed within at least one of the shank portion and the arbor portion of the substrate;
the material constituting the substrate includes a first metal;
the material constituting the at least one vibration damping body includes a second metal different from the first metal;
an intermetallic compound layer including a compound of the first metal and the second metal is formed at an interface between the substrate and the at least one vibration attenuator;
the at least one vibration damping body is a plurality of vibration damping bodies;
A vibration-proof tool holder, wherein in a cross section perpendicular to the axis, the multiple vibration damping bodies are arranged at intervals from one another in a circumferential direction about the axis. A method for manufacturing a vibration-proof tool holder that is rotated about an axis by a main shaft of a processing machine, comprising the steps of:
forming the vibration-proof tool holder by a metal additive manufacturing process, the vibration-proof tool holder comprising a base material and at least one vibration-damping body disposed inside the base material;
The forming step includes a first step of melting and solidifying a material constituting the base material by the metal additive manufacturing method, and a second step of melting and solidifying a material constituting the at least one vibration damping body by the metal additive manufacturing method ,
In the forming step, the vibration-proof tool holder including the at least one vibration attenuator, a first base material arranged to surround the at least one vibration attenuator, and a second base material arranged to surround the first base material is formed by the metal additive manufacturing method,
The first step includes a third step of melting and solidifying a material constituting the first base material by the metal additive manufacturing method, and a fourth step of melting and solidifying a material constituting the second base material by the metal additive manufacturing method .

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