Internal locking type cutting tool sleeve for cutting tool extrusion rod structure

Abstract

Regarding cutting tool sleeves, a cutting tool extrusion rod-shaped structure for an internal locking cutting tool sleeve is provided. [Solution] The device includes an outer sleeve (10), an inner sleeve (20), a push-out slide bar (30), a preload spring (40), and multiple positioning balls (50). The push-out slide bar includes a rod head (31), a rod tail (32), and a rod section (33). The rod head is located in the outer cylinder cavity. The rod tail is located in the inner cylinder cavity (23). The preload spring is provided between the rod tail and the annular wall. The push-out slide bar is placed in positioning mode when it is elastically pressed toward the inner port (12) of the through-hole (11). The rod head includes a first end (311) and a second end (312). The second end has an axially recessed avoidance groove at its center. Multiple recesses (314) are formed at the boundary between the first end and the second end. Each recess faces the inside of each positioning ball. An axial groove (315) is also formed between each recess and the first end. Each recess has a ball forward guide surface 316 and a ball backward guide surface formed at both axial ends thereof, which allows the cutting tool to be quickly retracted.

Description

[Technical Field]

[0001] The present invention relates to a cutting tool sleeve, and more particularly to a cutting tool push rod structure for an internal locking cutting tool sleeve. [Background technology]

[0002] A cutting tool sleeve is a tool clamping device with an internal clamping or locking mechanism, which is mainly used in the clamping structure of automatic tool magazines to safely and accurately clamp cutting tools (such as milling cutters and drill bits) and ensure stability and precision during the machining process.

[0003] The design of the cutting tool sleeve structure usually has a holding brake mechanism to achieve the function of quickly releasing the cutting tool, which is mainly pressed by a holding rod to retract the corresponding positioning balls inward to enter the release state and release the cutting tool.

[0004] Currently known pressure brake mechanisms typically use a single outer diameter extension on the pressure rod to guide the movement of the positioning ball and generate radial position changes. However, as known to those skilled in the art, cutting tools come in a variety of sizes, and the design of the conventional pressure rod to guide the positioning ball is limited in minimum outer diameter due to the minimum dimensions of the threaded portion and other factors. Therefore, conventional cutting tool sleeves are often impractical below certain size specifications, hindering the development of smaller and more specialized cutting tools in the industry. Summary of the Invention [Problem to be solved by the invention]

[0005] SUMMARY OF THE INVENTION The main object of the present invention is to provide a cutting tool pushing rod structure for an internal locking type cutting tool sleeve, which has a more ideal and practical cutting tool pushing structure. [Means for solving the problem]

[0006] The cutting tool extrusion rod structure for an internally locked cutting tool sleeve according to the present invention comprises an outer sleeve, an inner sleeve, an extrusion slide bar, a preload spring, and a plurality of positioning balls. The outer sleeve defines an axial direction and a radial direction and has a through hole formed in the axial direction. The through hole has an inner port and an outer port. The outer port has a trumpet-shaped holder insertion slot. The inner sleeve is fixed to the through hole. The inner sleeve is divided into an outer cylinder cavity and an inner cylinder cavity by an annular wall. The outer cylinder cavity has a plurality of ball holes formed in the radial direction, which are annular and communicate with the holder insertion slot. A plurality of positioning balls are provided in each ball hole, and have two states: outward protrusion and inward retraction. The extrusion slide bar comprises a rod head, a rod tail, and a rod section located between the rod head and the rod tail. The rod head is inserted into the outer cylinder cavity. The rod head is placed in the inner-cylinder cavity, the rod tail is placed in the inner-cylinder cavity, the preload spring is located between the rod tail and the annular wall and elastically presses them together, the push-out slide bar is elastically pressed toward the inner port of the through hole to enter the positioning mode, and conversely, when the push-out slide bar is pressed forward toward the outer port of the through hole under force, it enters the release mode. The rod head has a first end and a second end, and an axially recessed escape groove is formed in the center of the second end, and a plurality of recesses are formed at the boundary between the first end and the second end, each recess facing the inside of each positioning ball and serving as an accommodation space for the positioning ball when it retracts inward, an axial groove is formed between each recess and the first end, and a ball advance guide surface and a ball retract guide surface are formed at both axial ends of each recess, respectively, and a spacer rib extending along the axial direction is formed between each axial groove. [Effects of the Invention]

[0007] The cutting tool push-out rod structure for an internal locking cutting tool sleeve according to the present invention has the following advantages:

[0008] This innovative structural design and technical features further reduce the volume of the internal locking tool sleeve extrusion rod structure compared to conventional technology. The first and second ends of the extrusion slide bar head can be made into a straight cylindrical shape, enabling the industry to develop smaller and more specialized processing tools more quickly, bringing great practical advances and greater industrial benefits. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an exploded perspective view showing an embodiment of the present invention. [Figure 2] 1 is an exploded cross-sectional view showing an embodiment of the present invention. [Figure 3] 1 is an enlarged perspective view showing a push-out slide bar head according to an embodiment of the present invention; [Figure 4] FIG. 1 is a perspective view showing an assembled state of an embodiment of the present invention. [Figure 5] 1 is a cross-sectional view showing the assembled state of the embodiment of the present invention, illustrating the positioning mode of the push-out slide bar. FIG. [Figure 6] 1 is a cross-sectional view showing the assembled state of the embodiment of the present invention, showing the release mode of the push-out slide bar. FIG. [Figure 7] 10 is a view showing an embodiment of the present invention in which the cross-sectional shape of the axial groove is an arc shape. FIG. [Figure 8] 10 is a view showing a cross section of an axial groove according to an embodiment of the present invention, in which both sides are chamfered. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] Please refer to Figures 1 to 5. As shown in Figures 1 to 5, the cutting tool push-out rod structure for the internal locking cutting tool sleeve according to the present invention has practical forms which are merely examples, and are not limited to this structure in the utility model patent application.

[0012] The cutting tool push-out rod-shaped structure for an internally locked cutting tool sleeve according to the present invention comprises an outer sleeve 10, an inner sleeve 20, a push-out slide bar 30, a preload spring 40, and a plurality of positioning balls 50. The outer sleeve 10 defines an axial direction X and a radial direction Y. A through hole 11 is formed along the axial direction X. The through hole 11 includes an inner port 12 and an outer port 13. The outer port 13 is horn-shaped and forms a holder insertion slot 14. The inner sleeve 20 is fixed to the through hole 11. The inner sleeve 20 is divided by an annular wall 21 into an outer cylinder cavity 22 and an inner cylinder cavity 23. The outer cylinder cavity 22 is provided with a plurality of ball holes 24 in the radial direction, which communicate with the holder insertion slot 14. Accordingly, a positioning ball 50 is provided in each ball hole 24, and has a protruding state and an inward retracting state. The extrusion slide bar 30 includes a rod head 31, a rod tail 32, and a rod section 33 between the rod head 31 and the rod tail 32. The rod head 31 is placed in the outer cylinder cavity 22. The rod tail 32 is placed in the inner cylinder cavity 23. The preload spring 40 is located between the rod tail 32 and the annular wall 21 and presses both of them, elastically pressing the extrusion slide bar 30 toward the inner port 12 of the through hole 11, thereby entering the positioning mode. Conversely, when the extrusion slide bar 30 is pressed forward by a force toward the outer port 13 of the through hole 11, it enters the release mode. The rod head 31 includes a first end 311 and a second end 312. The second end 312 has an axially recessed avoidance groove 313 at its center. A plurality of recesses 314 are formed at the boundary between the first end 311 and the second end 312. Each recess 314 faces the inside of each positioning ball 50, thereby providing a storage space for each positioning ball 50 when it retracts inward. In addition, an axial groove 315 is formed between each recess 314 and the first end 311. A ball advance guide surface 316 and a ball retract guide surface 317 are formed at both axial ends of each recess 314, respectively. Spacer ribs 318 extending along the axial direction are formed between each axial groove 315.

[0013] In the above-described structure, the clearance groove 313 is referred to as an "avoidance" groove because it avoids the cutting fluid joint provided on the tool holder 60 inserted into the holder insertion slot 14. Meanwhile, an axial groove 315 is formed between the recess 314 and the first end 311. This mainly facilitates the assembly of the rod head 31 of the extrusion slide bar 30 into the outer cylinder cavity 22. Before assembling the rod head 31 into the outer cylinder cavity 22, the positioning balls 50 must be positioned in each ball hole 24 and protrude outward. However, without the axial groove 315, the rod head 31 would be trapped inside each positioning ball 50 and would not be able to be assembled into the outer cylinder cavity 22. Therefore, the axial groove 315 is mainly used to avoid the inside of the positioning balls 50. After assembling the rod head 31 into the outer cylinder cavity 22, the ball advance guide surface 316 of the recess 314 presses against the positioning balls 50 to position it.

[0014] Please refer to Fig. 2. In this embodiment, the outer diameters of the first end 311 and the second end 312 of the rod head 31 of the push-out slide bar 30 are approximately the same (or the same).

[0015] As shown in FIG. 2, the inside of the plurality of recesses 314 communicates with the avoidance groove 313 .

[0016] The radial depth H1 of the axial groove 315 is equal to the radial depth of the inner side when the corresponding positioning ball 50 is in the outwardly protruding state, as shown in FIG.

[0017] As shown in FIGS. 1 and 2, the rod head 31 and the rod section 33 of the extrusion slide bar 30 are connected to each other via a threaded portion 34 (that is, a threaded connection between a stud and a screw hole).

[0018] Based on the above configuration and technical features, the cutting tool push-out rod structure for an internally locked cutting tool sleeve disclosed in the present invention, as shown in Fig. 5, is for locking the cutting tool holder 60. It mainly utilizes the preload spring 40, located between the rod tail 32 and the annular wall 21 and pressing both of them, to elastically press the pushing slide bar 30 toward the inner port 12 of the through-hole 11 to enter the positioning mode. At this time, the ball advancement guide surface 316 at the axial lower end of the recess 314 presses each positioning ball 50, causing it to protrude out of the ball hole 24 and press against the slot portion 61 provided in the cutting tool holder 60 to lock it. Conversely, when attempting to release the cutting tool holder 60, as shown in Fig. 6, the rod tail 32 of the pushing slide bar 30 is subjected to an acting force L1 (note: this force is usually derived from the pressing mechanism of the automatic cutting tool magazine) and moves forward toward the outer port 13 of the through-hole 11 to enter the release mode. At this time, the ball advancement guide surface 316 at the axial lower end of the recess 314 is displaced downward, causing each positioning ball 50 to retreat into the ball hole 24. As a result, the cutting tool holder 60 is not positioned and can escape from the holder insertion slot 14 as shown by arrow L2.

[0019] In the present invention, the technical features of the recesses 314 and the axial grooves 315 ensure that the first end 311 and the second end 312 of the rod head 31 of the extrusion slide bar 30 are rod-shaped. The spacer ribs 318 formed between the axial grooves 315 and extending in the axial direction can greatly increase the structural strength of the rod head 31. This also simplifies handling of smaller cutting tools, accelerating the development of smaller specialized cutting tools in the industry.

[0020] The axial groove 315b may have a concave arcuate shape as shown in Fig. 7. Meanwhile, the axial groove 315c may have chamfered portions 35 formed on both sides thereof as shown in Fig. 8. The advantages of this embodiment are that it is possible to further increase the structural strength of the rod head 31 and to avoid the problem of excessive material removal that accompanies the formation of the axial groove 315c. [Explanation of symbols]

[0021] 10 Outer sleeve 11 Through holes 12 Internal Port 13. Outer Port 14 Holder insertion slot 20 Inner sleeve 21 Circular Wall 22 outer cylinder cavity 23 Inner cylinder cavity 24 Ball hole 30 Extrusion slide bar 31 Rod Head 311 first end 312 Second End 313 Avoidance Groove 314 Depression 315,315b,315c Axial groove 316 Ball advance guide surface 317 Ball retraction guideway 318 Spacer rib 32 Rod Tail 33 Rod Section 34 Screwing part 35 Chamfered area 40 preload spring 50 Positioning ball 60 Cutting Tool Holder 61 Slot area X-axis direction Y radial direction H1 Radial depth L1 acting force L2 arrow

Claims

1. The outer sleeve defines an axial direction and a radial direction, and has a through hole formed in the axial direction, the through hole having an inner port and an outer port, and a trumpet-shaped holder insertion slot formed in the outer port. The inner sleeve is fixed to the through hole. The inner sleeve is divided into an outer cylinder cavity and an inner cylinder cavity by an annular wall, and a plurality of ball holes are annularly formed in the radial direction of the outer cylinder cavity, and the ball holes communicate with the holder insertion slot. The plurality of positioning balls are provided in each ball hole, and have two states of protruding outward and retracting inward. The extrusion slide bar includes a rod head, a rod tail, and a rod section between the rod head and the rod tail. The rod head is placed in the outer cylinder cavity, and the rod tail is placed in the inner cylinder cavity. a spring is located between the rod tail and the annular wall and elastically presses both of them; the push-out slide bar is in a positioning mode when it is elastically pressed toward the inner port of the through hole, and conversely, when the push-out slide bar is pressed toward the outer port of the through hole and moves forward under force, it is in a release mode; the rod head has a first end and a second end, an escape groove recessed in the axial direction is formed in the center of the second end, a plurality of depressions are formed at the boundary between the first end and the second end, each depression faces the inside of each positioning ball and serves as an accommodation space for each positioning ball when it retracts inward, an axial groove is formed between each depression and the first end, a ball advance guide surface and a ball retract guide surface are formed at both axial ends of each depression,

2. The cutting tool extrusion rod structure for an internal locking type cutting tool sleeve according to claim 1, wherein the inside of the recess is formed to penetrate to the avoidance groove.

3. 2. The cutting tool extrusion rod-shaped structure for an internal locking type cutting tool sleeve according to claim 1, wherein the radial depth of the axial groove is the same as the inner radial depth of the corresponding positioning ball when it is protruding outward.

4. 2. The cutting tool extrusion rod-shaped structure for an internal locking cutting tool sleeve according to claim 1, wherein the rod head and the rod section of the extrusion slide bar are connected by a threaded portion interposed therebetween.

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