CLIAMS:We claim
1. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface and at least one locking member protruding from the inner surface generally normal to the central longitudinal axis and movable between a locked position and an unlocked position; and
a collet having a tool holder-engaging end and a tool receiving end and defining an outer surface having at least one recess configured to receive the locking member, the collet being configured to engage the inner surface of the tool holder,
wherein the locking member is configured to restrict motion of the collet relative to the tool holder in a direction generally parallel to the central longitudinal axis when disposed in the locked position.

2. The tool holder assembly of claim 1, wherein the tool holder has at least two locking members protruding from the inner surface of the tool holder generally normal to the central longitudinal axis.

3. The tool holder assembly of claim 1, wherein the locking member is biased toward the locked position.

4. The tool holder assembly of claim 3, wherein the locking member is biased by at least one spring.

5. The tool holder assembly of claim 1, wherein the locking member is movable between the locked position and the unlocked position by a screw.

6. The tool holder assembly of claim 1, wherein the recess is a notch.

7. The tool holder assembly of claim 1, wherein the recess is a groove disposed about the outer surface of the collet.

8. The tool holder assembly of claim 1, wherein the locking member and the recess have complementary shapes.

9. The tool holder assembly of claim 1, wherein the recess defines at least one member-receiving surface disposed at an angle relative to the central longitudinal axis of greater than 0°.

10. The tool holder assembly of claim 1, wherein the recess is a through-hole.

11. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface and a collet-receiving end;
a collet having a tool holder-engaging end and a tool receiving end, the collet being configured to engage the inner surface of the tool holder; and
at least two collet-locking members arranged generally parallel to the central longitudinal axis.

12. The tool holder assembly of claim 11, wherein the collet receiving end has at least two locking recesses configured to receive the at least two collet-locking members, the tool holder assembly further comprising at least two collet-locking tabs configured to be biased against the collet by the at least two collet-locking members.

13. The tool holder assembly of claim 11, wherein the collet has at least two receiving recesses, wherein the tool holder has at least two locking recesses on the collet receiving end, and wherein the collet-locking members are configured to engage receiving recesses and the locking recesses concurrently to restrict motion of the collet relative to the tool holder in a direction generally parallel to the central longitudinal axis.

14. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface with at least one depression disposed thereon; and
a collet having a tool holder-engaging end, a tool receiving end, and at least one protrusion configured to engage the depression, the collet being configured to engage the inner surface of the tool holder.

15. The tool holder assembly of claim 14, wherein the inner surface of the tool holder has at least two depressions disposed thereon, and wherein the collet has at least two protrusions configured to engage the at least two depressions.

16. The tool holder assembly of claim 14, wherein the depression is a groove disposed about a periphery of the inner surface of the tool holder, and wherein the protrusion is disposed about a periphery of the collet.

17. A tool holder assembly having a central longitudinal axis and comprising:
a tool holder having an inner surface defining at least one internal thread disposed about the central longitudinal axis; and
a collet having a tool holder-engaging end, a tool receiving end, and at least one external thread disposed about the central longitudinal axis and configured to engage the internal thread of the tool holder, the collet being configured to engage the inner surface of the tool holder.

18. The tool holder assembly of claim 17, wherein the tool holder further comprises an axial bore generally parallel to the central longitudinal axis, and wherein the collet further comprises a primary outer surface portion and a secondary outer surface portion, the secondary outer surface portion having a smaller diameter than the primary outer surface portion, the secondary outer surface portion and the axial bore being configured to mate by precision fit.

19. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface;
a collet configured to engage the inner surface of the tool holder and having at least one thread disposed about the central longitudinal axis; and
a threaded locking member configured to engage the thread of the collet to restrict motion of the collet in a direction generally parallel to the central longitudinal axis.

20. The tool holder assembly of claim 19, wherein the thread is an internal thread, and wherein the threaded locking member is an axial screw having an external thread corresponding to and configured to engage with the internal thread.

21. The tool holder assembly of claim 20, wherein the thread is an external thread, and wherein the threaded locking member is a boss having an internal thread corresponding to and configured to engage with the external thread.
,TagSPECI:FIELD
The present invention relates to tool holder assemblies and, in particular, to tool holder assemblies employing one or more mechanisms designed to reduce or eliminate tool pull-out and/or radial slip.

BACKGROUND
Rotational machining operations, such as milling, drilling, tapping, boring, reaming and deburring generally utilize a rotating tool holder for interfacing with cutting tools having a variety of designs and geometries. In order to securely retain such tools, tool holders are often provided with reducer sleeves or collets suitable for receiving differently sized and/or shaped tool shanks. Collets, for example, can be used to facilitate rapid replacement of differing tool shank diameters, thereby leading to cutting operation efficiencies. However, such configurations may introduce a number of component interfaces conducive to permitting movement relative to adjacent components. For example, a machining operation can sometimes induce torque on the cutting tool resulting in axial movement of the cutting tool shank or collet relative to the tool holder, an effect referred to as “pull-out”. In addition, such operations can sometimes induce forces resulting in radial movement or “radial slip”.

Tool holder assemblies, therefore, must be capable of accurately and securely retaining a tool while minimizing detrimental effects to surface finish and machine tolerance as a result of pull-out and/or radial slip. Various mechanisms and configurations have been developed for securing cutting tools into tool holder, but such configurations may present deficiencies in reducing pull-out and/or radial slip. Tool holder design continues to evolve in response to the changing demands of rotational cutting, milling, drilling, tapping and boring applications, thereby calling for the development of new tool holder configurations.

SUMMARY
In one aspect, tool holder assemblies are described herein comprising architecture which restricts motion of a collet relative to an associated tool holder. For example, a tool holder assembly described herein defines a central longitudinal axis and comprises a tool holder and a collet. The tool holder has an inner surface and at least one locking member protruding from the inner surface generally normal to the central longitudinal axis and movable between a locked position and an unlocked position. The collet has a tool holder -engaging end and a tool receiving end and defines an outer surface having at least one recess configured to receive the locking member, the collet being configured to engage the inner surface of the tool holder. The locking member is configured to restrict motion of the collet relative to the tool holder in an axial direction, generally parallel to the central longitudinal axis when the locking member is disposed in the locked position.

In another aspect, a tool holder assembly is described herein defining a central longitudinal axis and comprising a tool holder, a collet and at least two collet-locking members arranged generally parallel to the central longitudinal axis. The tool holder has an inner surface and a collet-receiving end, and the collet has a tool holder-engaging end and a tool receiving end, the collet being configured to engage the inner surface of the tool holder. The collet receiving end has at least two locking recesses configured to receive the two collect-locking members. The tool holder assembly can further comprise at least two collet-locking tabs configured biased against the collet by the at least two collet-locking members.

In a further aspect, a tool holder assembly is described herein defining a central longitudinal axis and comprising a tool holder and a collet. The tool holder has an inner surface with at least one depression disposed thereon, and the collet has a tool holder engaging end, a tool receiving end, and at least one protrusion configured to engage the depression, the collet being configured to engage the inner surface of the tool holder.

In a yet further aspect, a tool holder assembly is described herein defining a central longitudinal axis and comprising a tool holder and a collet. The tool holder has an inner surface defining at least one internal thread disposed about the central longitudinal axis. The collet has a tool holder-engaging end, a tool receiving end, and at least one external thread disposed about the central longitudinal axis and configured to engage the internal thread of the tool holder. The collet is configured to engage the inner surface of the tool holder.

In an additional aspect, a tool holder is described herein defining a central longitudinal axis and comprising a tool holder, a collet, and a threaded locking member. The tool holder has an inner surface, and the collet is configured to engage the inner surface of the tool holder, the collet having at least one thread disposed about the central longitudinal axis. The threaded locking member is configured to engage the thread of the collet to restrict motion of the collet in a direction generally parallel to the central longitudinal axis.

These and other embodiments are described in further detail in the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 1B illustrates a sectional view of a portion of the tool holder assembly of Figure 1A.

Figure 2A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 2B illustrates a sectional view of a portion of the tool holder assembly of Figure 2A.

Figure 3A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 3B illustrates a sectional view of a portion of the tool holder assembly of Figure 3A.

Figure 3C illustrates a cross-sectional view of the collet of the tool holder assembly of Figure 3A.

Figures 4A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 4B illustrates a sectional view of a portion of the tool holder assembly of Figure 4A.

Figure 4C illustrates a cross-sectional view of the collet of the tool holder assembly of Figure 4A.

Figure 5A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 5B illustrates a sectional view of a portion of the tool holder of Figure 5A.

Figure 5C illustrates a cross-sectional view of the collet of the tool holder assembly of Figure 5A.

Figure 6 illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 7A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 7B illustrates a cross-sectional view of a portion of the collet of the tool holder assembly of Figure 7A.

Figure 8A illustrates a cross-sectional view of a tool holder system according to one embodiment described herein.

Figure 8B illustrates a sectional view of a portion of the tool holder assembly of Figure 8A.

Figure 8C illustrates a cross-sectional view of the collet of the tool holder assembly of Figure 8A.

Figure 9A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 9B illustrates a sectional view of a portion of the tool holder assembly of Figure 9A.

Figure 9C illustrates a cross-sectional view of the collet of the tool holder assembly of Figure 9A.

Figure 10A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.
Figure 10B illustrates a sectional view of a portion of the tool holder assembly of Figure 10A.

Figure 10C illustrates a cross-sectional view of the collet of the tool holder assembly of Figure 10A.

Figure 11A illustrates a cross-sectional view of a tool holder assembly according to one embodiment described herein.

Figure 11B illustrates a sectional view of a portion of the tool holder assembly of Figure 11A.

Figure 11C illustrates a composite view of the tool holder assembly of Figure 11A including a cross-sectional view of a tool holder and a perspective view of a collet.

DETAILED DESCRIPTION
Embodiments described herein can be understood more readily by reference to the following detailed description and examples and their previous and following descriptions. Elements and apparatus described herein, however, are not limited to the specific embodiments presented in the detailed description. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations will be readily apparent to those of skill in the art without departing from the spirit and scope of the invention.

Tool holder assemblies described herein generally comprise a tool holder and a collet configured to engage the tool holder concurrent with engagement of a cutting tool. Tool holders and collets described herein can engage one another in any manner and by any means not inconsistent with the objectives of the present invention. For example, a collet can have one or more slits, slots, or other areas configured to permit expansion and contraction of the collet in order to grip or retain a cutting tool when external force is applied to an outer surface of the collet. Tool holders described herein can be configured to apply such an external force by any means or by any structure. For example, in some embodiments, tool holders of tool holder assemblies described herein utilize hydraulic chuck configurations wherein hydraulic pressure is applied to an inner surface of the tool holder. The hydraulic pressure can then be applied to the outer surface of the collet, forcing contraction of the collet, thereby enacting securement of the cutting tool to be used in the cutting, milling, boring, or deburring operation.

I. Tool Holder Assemblies Comprising a Radial Locking Member
Referring now to Figures 1-5, there is illustrated a tool holder assembly, generally designated as reference number 100, in accordance with several embodiments described herein. As illustrated in Figure 1A, the tool holder assembly (100) defines a central longitudinal axis (A A) and comprises a tool holder (200) and a collet (300). The tool holder (200) has an inner surface (210) and at least one locking member (220) protruding from the inner surface (210) generally normal to the central longitudinal axis (A-A) and movable between a locked position and an unlocked position. A locking member (220) oriented generally normal to the central longitudinal axis (A-A) may be said to be a “radial” locking member (220). The collet (300) has a tool holder-engaging portion, or end (310) and a tool receiving portion, or end (320) and defines an outer surface (330) having at least one recess (340) configured to receive the at least one locking member (220). The collet (300) is configured to engage the inner surface (210) of the tool holder (200). The at least one locking member (220) is configured to restrict motion of the collet (300) relative to the tool holder (200) in a direction generally parallel to the central longitudinal axis (A-A) when disposed in the locked position.Any tool holder (200) can be used not inconsistent with the objectives of the present invention. For example, in some embodiments, a tool holder comprises a hydraulic chuck, high performance milling chuck (HPMC), a collet chuck or the like. In addition, any collet (300) can be used not inconsistent with the objectives of the present invention. In some embodiments, as illustrated in Figures 1-5, the collet (300) can have a cylindrical or substantially cylindrical cross-sectional profile or shape. Other cross-sectional profiles are also possible, such as polygonal. In some cases, a collet (300) comprising an outer surface (330) includes two or more portions of differing diameters or widths, as shown in Figures 1-5. Such portions may be characterized as a primary outer surface portion (331) and a secondary outer surface portion (332). In certain embodiments, the secondary outer surface portion (332) has a smaller diameter or width than the primary outer surface portion (331). In some such embodiments, a recess (340) can be disposed on the secondary outer surface portion (332). In some cases, the secondary outer surface portion (332) is disposed at the tool holder-engaging end (310). In other cases, the collet (300) can have one or more tapered portions. Such collets (300) can define a frustoconical or conical shape, or can define a complex geometrical shape including one or more cylindrical or polygonal segments and/or one or more conical or frustoconical segments.

A tool holder assembly can have any number of locking members. In some cases, as illustrated in Figures 1A, 1B, 2A, and 2B, the tool holder (200) has at least two locking members (220) protruding from the inner surface (210) of the tool holder (200) generally normal to the central longitudinal axis (A-A). In additional embodiments, the tool holder (200) has at least three or at least four locking members (220) protruding from the inner surface (210). The locking member (220), while movable between a locked position and an unlocked position, can be biased towards the locked position or the unlocked position. Biasing force may be applied by any means or by any structure not inconsistent with the objectives of the present invention. For example, in some cases, the at least one locking member (220) is biased by a spring (221). In certain other embodiments, the locking member is biased by hydraulic pressure. Figures 3A and 3B, for example, illustrate an embodiment of a tool holder assembly (100) comprising at least one locking member (220) biased by a spring (221). The locking member (220) can be movable between the locked position and the unlocked position by any means or by any structure not inconsistent with the objectives of the present invention. For example, in some embodiments, the locking member (220) is movable between the locked position and the unlocked position by a screw. One such embodiment can comprise a locking member (220) having at least one thread disposed about the locking member (220), the thread being threadingly engagable with a corresponding thread on the tool holder (200). In such embodiments, turning the locking member (220) such as with a screwdriver, hex key, or similar implement will engage or disengage the locking member relative to the recess (340).

The recess can have any shape or configuration. For example, the recess (340) can be a notch. A notch can have any profile, shape, or dimensions operable to engage at least one locking member (220). As illustrated in Figures 3A and 3B, a notch can be rounded. In other embodiments, as illustrated in Figures 2A and 2B, the notch can be shaped such that the profile of the notch is complementary to the locking member (220) profile. Such a configuration can facilitate locking engagement of the locking member (220) and the recess (340) such that the locking member (220) fills or substantially fills the recess (340). In certain cases, the recess (340) defines a base surface (341) disposed at an angle (?) relative to the central longitudinal axis (A-A) of greater than 0°. Any angle can be used not inconsistent with the objectives of the present invention. In such embodiments, the base surface (341) engages the locking member (220) in a manner providing resistance to movement of the collet (300) in a direction parallel to the central longitudinal axis (A-A). An example of such an embodiment is illustrated in Figures 4A and 4B. Base surface (341) is disposed at angle ? relative to longitudinal axis A-A. Inclination in base surface (341) restricts movement of the engaging locking member (220) in direction parallel to the central longitudinal axis (A-A).

In some embodiments, as illustrated figure 3C, the recess (340) is a groove disposed about the outer surface (330) of the collet (300). A groove can be disposed about the entirety of the circumference, diameter, or perimeter of the outer surface (330), or can be disposed about a portion comprising less than the entirety of the circumference, diameter, or perimeter of the outer surface (330). In certain other embodiments, as illustrated in Figures 5A, 5B, and 5C, the recess (340) is a through-hole. A “through-hole”, for reference purposes herein, is a recess or hole passing through an entirety of a collet (300) such that a corresponding locking member (220) can pass through the hole to an opposing side of the collet (300). In some such embodiments, the tool holder (200) can comprise a secondary recess (230) configured to receive the locking member (220), as shown in Figures 5A and 5B.

II. Tool Holder Assemblies Comprising an Axial Locking Member
Referring now to Figures 6, 7A, and 7B there is illustrated a tool holder assembly, generally designated as reference number 400, in accordance with several embodiments described herein. As shown in Figure 6, a tool holder assembly (400) defines a central longitudinal axis (B-B) and comprises a tool holder (500), a collet (600), and at least two collet-locking members (550) arranged generally parallel to the central longitudinal axis (B-B). The tool holder (500) has an inner surface (510) and a collet-receiving end (520), and the collet (600) has a tool holder-engaging end (610) and a tool receiving end (620), the collet (600) being configured to engage the inner surface (510) of the tool holder (500). The at least two collet-locking members (550) arranged generally parallel to the central longitudinal axis (B-B) may be referred to as axial locking members.
A tool holder (500) of a tool holder assembly (400) described herein can comprise at least two locking recesses (530) configured to receive the at least two collet-locking members (550). The locking recesses (530) can have any shape, dimensions, configuration, or architecture operable to engage or receive the collet-locking members (550). For example, in some cases, the locking recesses (530) comprise or consist of smooth-walled bores configured to receive a locking pin. In certain other embodiments, the locking recesses (530) can comprise or consist of an internal thread for threadingly engaging the at least two collet-locking members (550). In further embodiments, the locking recesses (530) can have a cross-sectional profile or shape configured to receive a similarly shaped collet-locking member (550) in a limited number of rotational configurations. Additionally, the locking recesses (530) can be sized or otherwise configured so as to retain or receive the collet-locking members (550) through resistance fit, precision fit, and/or interference fit.

Virtually any collet (600) can be used consistent with the disclosure provided above in Section I. In addition, a collet (600) may comprise or include additional structure or components in order to accommodate or engage the at least two collet-locking members (550) or axial locking members. One such embodiment is shown in Figures 7A and 7B. In the embodiment of Figures 7A and 7B, the collet (600) has at least two receiving recesses (630). Receiving recesses (630) can be sized and/or shaped so as to permit the at least two collet-locking members (550) to pass through or otherwise engage the receiving recesses (630). In some embodiments, the receiving recesses (630) comprise through-holes operable to permit the at least two collet-locking members (550) to engage the receiving recesses (630) of the collet (600) and the locking recesses (530) concurrently. The receiving recesses (630), in some embodiments, comprise threads operable to threadingly engage the at least two collet-locking members (550).

Collet-locking members (550) can have any dimensions or architecture not inconsistent with the objectives of the present invention. For example, in some embodiments, the collet locking members (550) comprise pins, bolts, screws or combinations thereof. Collet locking members (550) can comprise at least one thread operable to threadingly engage one or more of the locking recesses (530) and/or the receiving recesses (630). In some cases, the tool holder assembly further comprises at least two collet-locking tabs (540) configured to be biased against the collet (600) by the at least two collet-locking members (550). One such embodiment is illustrated in Figure 6, wherein the collet-locking members (550) engage the collet-locking tabs (540) and the locking recesses (540) in such a manner that the tabs are biased against the collet (600), thereby restricting movement of the collet (600) to restrict motion of the collet (600) relative to the tool holder (500) in a direction generally parallel to the central longitudinal axis (B-B).

III. Tool Holder Assemblies Comprising a Protrusion on a Collet
Referring now to Figures 8A, 8B, and 8C, there is illustrated a tool holder assembly, generally designated as reference number 700, in accordance with one embodiment described herein. As shown in Figure 8A, a tool holder assembly (700) defines a central longitudinal axis (C-C) and comprises a tool holder (800) and a collet (900). The tool holder (800) has an inner surface (810) with at least one depression or recess (820) disposed thereon, and the collet (900) has a tool holder-engaging end (910), a tool receiving end (920), and at least one protrusion (930) configured to engage the tool holder depression (820), the collet (900) being configured to engage the inner surface (810) of the tool holder (800).

Virtually any collet can be used consistent with the disclosure provided above in Section I. In addition, a collet (900) may comprise or include additional structure or components in order to accommodate at least one protrusion (930). As described in Section I, a collet (900) can comprise an outer surface (940) having a primary outer surface portion (941) and a secondary outer surface portion (942). The primary and secondary outer surface portions (941, 942) can have differing diameters or widths. As shown in Figure 8A, the primary outer surface portion (941) can have a diameter or width that is larger than the secondary outer surface portion (942). The secondary outer surface portion (942) can be disposed at the tool holder-engaging end (910). In the embodiment of Figures 8A and 8B, the collet (900) has at least one protrusion disposed at the tool holder-engaging end (910) configured to engage the tool holder depression (820).

In some embodiments, the protrusion is a curved bump or a non-actuatable locking detent. In certain other cases, the protrusion is a raised groove around a circumference of the outer surface of the collet (900) at a tool holder-engaging end (910). In certain embodiments, the protrusion (930) is disposed on the secondary outer surface portion (942). In other embodiments, the protrusion (930) is disposed on the primary outer surface portion (941) of the collet (900). Protrusions (930) can be sized and/or shaped in any manner so as to engage the depression (820) or recess. A collet (900) can have any number of protrusions (930). For example, a collet can have at least two protrusions (930) or at least three protrusions (930).

The depression (820) can have any size and/or shape consistent with the objectives of the present invention. In some embodiments, for example, the depression (820) is a single notch or recess configured to receive a rounded bump or non-actuatable detent. In certain other cases, the depression (820) is a groove disposed about a portion of or an entirety of the inner surface (810) circumference. Further, other shapes or configurations are possible that can provide locking and unlocking operability. For example, a depression (820) have a polygonal or complex polygonal shape so as to receive the protrusion (930) in a direction parallel to the central longitudinal axis (C-C), and to lock or receive the protrusion (930) in a second direction by rotating the collet (900) about the central longitudinal axis (C-C). In some cases, such a configuration can provide generally an L-shape, although other shapes or configurations are contemplated to achieve such function.

IV. Tool Holder Assemblies Comprising an External Thread
Referring now to Figures 9A, 9B, and 9C, there is illustrated a tool holder assembly, generally designated as reference number 1000, in accordance with one embodiment described herein. As shown in Figure 9A, a tool holder assembly (1000) defines a central longitudinal axis (D-D) and comprises a tool holder (1100) and a collet (1200). The tool holder (1100) has an inner surface (1110) defining at least one internal thread (1120) disposed about the central longitudinal axis (D-D). The collet (1200) has a tool holder engaging end (1210), a tool receiving end (1220), and at least one external thread (1230) disposed about the central longitudinal axis (D-D) and configured to engage the internal thread (1120) of the tool holder (1100), the collet (1200) being configured to engage the inner surface (1110) of the tool holder (1100).

An internal thread (1120) disposed on the inner surface (1110) of a tool holder (1100) can have any architecture or configuration not inconsistent with the objectives of the present invention. For example, an internal thread (1120) can be disposed on a portion of the inner surface (1110) less than the entirety of the inner surface (1110). One such embodiment is illustrated in Figures 9A, 9B, and 9C. For example, an internal thread (1120) can comprise less than 50%, less than 25%, or less than 10% of the surface area of an inner surface (1110) of a tool holder (1100). Further, a tool holder can have an axial bore (1130) disposed generally parallel to the central longitudinal axis (D-D). An axial bore (1130) can be disposed opposite a collet receiving opening and can have a diameter or width differing from a diameter or width of the inner surface (1110). In the embodiment illustrated in Figure 9A, the axial bore (1130) has a smaller diameter or width than the inner surface (1110).

Virtually any collet can be used consistent with the disclosure provided above in Section I. In addition, a collet (1200) may comprise or include additional structure or components in order to accommodate at least one external thread (1230). Any thread configuration or architecture can be used not inconsistent with the objectives of the present invention. For example, an external thread (1230) can be sized or arranged in a manner permitting threaded engagement of the internal thread (1120). In some embodiments, the internal and external threads (1120, 1230) are arranged in a manner or direction such that rotation of a cutting tool applies torque operable to tighten the threaded engagement, thereby restricting axial movement of the collet (1200) relative to the tool holder (1100) in a direction generally parallel to the central longitudinal axis (D-D). As described in Section I, a collet (1230) can comprise an outer surface (1240) having a primary outer surface portion (1241) and a secondary outer surface portion (1242). The primary and secondary outer surface portions (1241, 1242) can have differing diameters or widths. As shown in Figure 9C, the primary outer surface portion (1241) can have a diameter or width that is larger than the secondary outer surface portion (1242). The secondary outer surface portion (1242) can be disposed at the tool holder-engaging end (1210). In some embodiments, the secondary outer surface portion (1242) is configured to be inserted into or to engage an axial bore (1130) in a tool holder (1100). In some cases, the secondary outer surface portion (1242) is sized and/or shaped such that the secondary outer surface portion (1242) and the axial bore (1130) can mate by precision fit such that there is no gap or spacing between the secondary outer surface portion (1242) and the axial bore (1130) in an assembled position.

V. Tool Holder Assemblies Comprising a Threaded Locking Member
Referring now to Figures 10A through 11C, there is illustrated a tool holder assembly, generally designated as reference number 1300, in accordance with several embodiments described herein. As shown in Figures 10A and 11A, a tool holder assembly (1300) defines a central longitudinal axis (E-E) and comprises a tool holder (1400), a collet (1500) and a threaded locking member (1600). The tool holder (1400) has an inner surface (1410), the collet (1500) is configured to engage the inner surface (1410) of the tool holder (1400) and has at least one thread (1510) disposed about the central longitudinal axis (E-E). The threaded locking member (1600) is configured to engage the thread (1510) of the collet (1500) to restrict motion of the collet (1500) in a direction generally parallel to the central longitudinal axis (E-E).

Virtually any collet can be used consistent with the disclosure provided above in Section I. In addition, a collet (1500) may comprise or include additional structure or components in order to accommodate at least one thread (1510) disposed about the central longitudinal axis (E-E). For example, a collet (1500) can have an outer surface (1520) comprising a primary outer surface portion (1521) and a secondary outer surface portion (1522) differing in diameter from the primary outer surface portion (1521). In some embodiments, the thread (1510) is disposed on the primary outer surface portion (1521). In certain other embodiments, the thread (1510) is disposed on the secondary outer surface portion (1522) as illustrated in Figures 10B, 11B and 11C.

In the embodiments shown in Figures 10A, 10B, and 10C, the thread (1510) is an internal thread disposed on an interior portion of the collet (1500) corresponding to a secondary outer surface portion (1522). In embodiments comprising at least one internal thread (1510), the threaded locking member (1600) can have at least one thread (1610) that is an external thread corresponding to and configured to engage with the internal thread. In some cases, a threaded locking member (1600) comprising an external thread (1610) is a screw, bolt, or threaded pin configured to align or be collinear with the central longitudinal axis (E-E). Such threaded locking members (1600) may be characterized as an axial screw. In the embodiments illustrated in Figures 11A-11C, the thread (1510) on the collet (1500) is an external thread disposed on the secondary outer surface portion (1522) of the collet (1500). In such embodiments, the threaded locking member (1600) is a boss having at least one thread (1610) that is an internal thread corresponding to and configured to engage with the thread (1510) on the collet (1500). In such an embodiment, the threaded locking member (1600) can further comprise a locking nut (1620) configured to threadedly engage the locking member (1600) to restrict axial movement of the threaded locking member (1600) in a direction generally parallel to the central longitudinal axis (E-E).
In embodiments comprising a threaded locking member (1600), a threaded engagement of the threaded locking member (1600) and a collet (1500) can restrict motion of the collet in a direction generally parallel to the central longitudinal axis (E-E). Further, at least one threaded locking member (1600) can provide operability such that rotation or turning of the threaded locking member (1600) about the central longitudinal axis (E-E) can drive the collet (1500) to move in an axial direction towards the tool holder (1400), thus providing a tightening force on the collet (1500) in addition to restriction of axial movement.

Various embodiments of the invention have been described in fulfillment of the various objects of the invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations thereof will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention.
We claim
1. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface and at least one locking member protruding from the inner surface generally normal to the central longitudinal axis and movable between a locked position and an unlocked position; and
a collet having a tool holder-engaging end and a tool receiving end and defining an outer surface having at least one recess configured to receive the locking member, the collet being configured to engage the inner surface of the tool holder,
wherein the locking member is configured to restrict motion of the collet relative to the tool holder in a direction generally parallel to the central longitudinal axis when disposed in the locked position.

2. The tool holder assembly of claim 1, wherein the tool holder has at least two locking members protruding from the inner surface of the tool holder generally normal to the central longitudinal axis.

3. The tool holder assembly of claim 1, wherein the locking member is biased toward the locked position.

4. The tool holder assembly of claim 3, wherein the locking member is biased by at least one spring.

5. The tool holder assembly of claim 1, wherein the locking member is movable between the locked position and the unlocked position by a screw.

6. The tool holder assembly of claim 1, wherein the recess is a notch.

7. The tool holder assembly of claim 1, wherein the recess is a groove disposed about the outer surface of the collet.

8. The tool holder assembly of claim 1, wherein the locking member and the recess have complementary shapes.

9. The tool holder assembly of claim 1, wherein the recess defines at least one member-receiving surface disposed at an angle relative to the central longitudinal axis of greater than 0°.

10. The tool holder assembly of claim 1, wherein the recess is a through-hole.

11. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface and a collet-receiving end;
a collet having a tool holder-engaging end and a tool receiving end, the collet being configured to engage the inner surface of the tool holder; and
at least two collet-locking members arranged generally parallel to the central longitudinal axis.

12. The tool holder assembly of claim 11, wherein the collet receiving end has at least two locking recesses configured to receive the at least two collet-locking members, the tool holder assembly further comprising at least two collet-locking tabs configured to be biased against the collet by the at least two collet-locking members.

13. The tool holder assembly of claim 11, wherein the collet has at least two receiving recesses, wherein the tool holder has at least two locking recesses on the collet receiving end, and wherein the collet-locking members are configured to engage receiving recesses and the locking recesses concurrently to restrict motion of the collet relative to the tool holder in a direction generally parallel to the central longitudinal axis.

14. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface with at least one depression disposed thereon; and
a collet having a tool holder-engaging end, a tool receiving end, and at least one protrusion configured to engage the depression, the collet being configured to engage the inner surface of the tool holder.

15. The tool holder assembly of claim 14, wherein the inner surface of the tool holder has at least two depressions disposed thereon, and wherein the collet has at least two protrusions configured to engage the at least two depressions.

16. The tool holder assembly of claim 14, wherein the depression is a groove disposed about a periphery of the inner surface of the tool holder, and wherein the protrusion is disposed about a periphery of the collet.

17. A tool holder assembly having a central longitudinal axis and comprising:
a tool holder having an inner surface defining at least one internal thread disposed about the central longitudinal axis; and
a collet having a tool holder-engaging end, a tool receiving end, and at least one external thread disposed about the central longitudinal axis and configured to engage the internal thread of the tool holder, the collet being configured to engage the inner surface of the tool holder.

18. The tool holder assembly of claim 17, wherein the tool holder further comprises an axial bore generally parallel to the central longitudinal axis, and wherein the collet further comprises a primary outer surface portion and a secondary outer surface portion, the secondary outer surface portion having a smaller diameter than the primary outer surface portion, the secondary outer surface portion and the axial bore being configured to mate by precision fit.

19. A tool holder assembly defining a central longitudinal axis and comprising:
a tool holder having an inner surface;
a collet configured to engage the inner surface of the tool holder and having at least one thread disposed about the central longitudinal axis; and
a threaded locking member configured to engage the thread of the collet to restrict motion of the collet in a direction generally parallel to the central longitudinal axis.

20. The tool holder assembly of claim 19, wherein the thread is an internal thread, and wherein the threaded locking member is an axial screw having an external thread corresponding to and configured to engage with the internal thread.

21. The tool holder assembly of claim 20, wherein the thread is an external thread, and wherein the threaded locking member is a boss having an internal thread corresponding to and configured to engage with the external thread.

Dated this 29th day of January, 2015
P. H. D. RANGAPPA
IN/PA 1538
OF K&S PARTNERS
AGENT FOR THE APPLICANT

TITLE: “TOOL HOLDER ASSEMBLIES WITH NON-PULL-OUT FUNCTIONALITY”

ABSTRACT

In one aspect, tool holder assemblies employing structure operable to reduce or eliminate axial pull-out and radial slip are described herein. A tool holder assembly described herein can comprise a tool holder having an inner surface, a collet having an outer surface, and at least one component or other means operable to retain the collet within the tool holder. Tool holder assemblies can further comprise at least one locking member, at least one protrusion, and/or at least one threaded portion.