High-stability CNC cutter handle structure aiming at low-frequency vibration

Abstract

The invention relates to the technical field of cutter handles, in particular to a high-stability CNC cutter handle structure for low-frequency vibration, comprising a cutter handle mechanism which comprises an upper cutter handle fixedly connected with a main shaft of a main machine and a lower cutter handle in threaded connection with the upper cutter handle; a driving cavity is formed in the upper cutter handle, and a driving assembly is arranged in the driving cavity; a collet chuck cavity is formed in the lower cutter handle in a penetrating mode along the axis of the lower cutter handle, and a collet chuck assembly is arranged in the collet chuck cavity. The collet chuck assembly comprises a collet chuck which is arranged in the collet chuck cavity and is in threaded connection with the driving assembly, and a cutter damping clamping piece arranged on the collet chuck. The problems that a cutter handle of a traditional CNC cutter handle structure is high in installation operation difficulty, the cutter is clamped unstably due to low-frequency vibration in the machining process after installation, and the cutter handle is damaged are solved. And the flatness of a machined surface is not high.

Description

Technical Field

[0001] This invention relates to the field of tool holder technology, and more specifically, to a highly stable CNC tool holder structure for low-frequency vibrations. Background Technology

[0002] During CNC machining, stable tool clamping is crucial for ensuring machining accuracy and workpiece quality. As a key component in the tool holder structure that connects the tool to the machine tool spindle, the design of the collet directly affects the stability and vibration of the tool during machining.

[0003] Traditional collet structures typically rely on friction against the inner wall of the collet cavity to clamp the tool. In actual operation, the drive assembly is screwed to the collet, and the screw drives the collet to move upward until the collet comes into contact with the inner wall of the collet cavity and contracts, thereby clamping the internal tool.

[0004] However, during this process, before the drive assembly screws the collet into place and moves it upward, it is essential to ensure that the collet has sufficient contact friction with the inner wall of the collet cavity. Otherwise, the operation of the drive assembly will cause the collet to rotate synchronously instead of moving upward, thus failing to achieve effective tool clamping. To achieve this prerequisite, it is usually necessary to manually rotate the collet so that it forms contact with the inner wall of the collet cavity while screwing into the drive assembly. However, if the tool is inserted before the collet forms contact with the inner wall of the collet cavity during this manual tightening process, the tool is not fixed when the collet and drive assembly are screwed together and is prone to falling. Therefore, it is easy for the lower end of the fixed tool to be lower than the set height after the collet retracts. If the tool is inserted after contact is formed, the insertion difficulty will increase or even make it impossible to insert because the collet has partially retracted.

[0005] Secondly, due to the clearance between the tool's entry point and the collet's inner cavity, low-frequency vibrations are prone to occur at the tool's entry point during machining. Although the amplitude of this vibration is small, it is enough to affect the flatness of the workpiece's machined surface and reduce the machining quality. In particular, for high-precision machining, this low-frequency vibration has become an important factor restricting the improvement of machining accuracy.

[0006] To address the aforementioned issues, a highly stable CNC tool holder structure for low-frequency vibrations is proposed. Summary of the Invention

[0007] (a) Technical problems to be solved

[0008] To address the problems existing in the prior art, the present invention provides a highly stable CNC tool holder structure for low-frequency vibration, thereby solving the problems mentioned in the background art, such as the high difficulty of tool holder installation and operation in traditional CNC tool holder structures, and the unstable tool clamping caused by low-frequency vibration during machining, resulting in poor surface flatness.

[0009] (II) Technical Solution

[0010] To achieve the above objectives, the present invention provides the following technical solution: a highly stable CNC tool holder structure for low-frequency vibration, comprising a tool holder mechanism, which includes an upper tool holder fixedly connected to the main spindle, and a lower tool holder threadedly connected to the upper tool holder;

[0011] The upper tool holder has a drive cavity, and a drive assembly is provided in the drive cavity;

[0012] The lower tool holder has a collet cavity extending through its axis, and a collet assembly is provided inside the collet cavity;

[0013] The collet assembly includes a collet disposed within the collet cavity and screwed to the drive assembly, and a tool damping clamping member disposed on the collet.

[0014] The present invention is further configured such that the driving cavity is composed of a worm cavity and a turbine cavity, and the worm cavity and the turbine cavity are connected;

[0015] The drive assembly includes a worm disposed within the worm chamber and a turbine disposed within the turbine chamber.

[0016] The present invention is further configured such that the collet includes a threaded rod screwed to the turbine, a cylinder disposed at the bottom end of the threaded rod, and a clamping plate disposed at the bottom end of the cylinder and arranged in a ring array.

[0017] The present invention is further configured such that the clamping plate is an arc-shaped plate, and there is a gap between the multiple sets of clamping plates in the annular array, wherein the diameter of the circle formed by the multiple sets of clamping plates in the annular array near the end of the cylinder is smaller than the diameter of the circle formed by the clamping plates away from the end of the cylinder.

[0018] The invention is further configured such that a tool slot is provided at the bottom end of the cylinder, and the diameter of the tool slot matches the diameter of the circle formed by the multiple sets of clamping plates in the annular array near one end of the cylinder.

[0019] The present invention is further configured such that the inner wall of the tool slot is provided with a receiving groove, and the receiving groove is provided with through holes in a ring array;

[0020] The tool damping clamping component includes clamping blocks arranged in a ring array within the receiving groove, a movable rod disposed on the side wall of the clamping blocks and movably inserted into the through hole, and a rubber ring sleeved on the outside of the cylinder.

[0021] The present invention is further configured such that the bottom end of the clamping block is provided with a wedge-shaped surface.

[0022] The present invention is further configured such that an inner groove is formed on the outer wall of the cylinder, and the inner groove is arranged in a ring shape, the inner groove and the through hole are located on the same horizontal line and are connected to each other;

[0023] An expansion block is provided at the end of the movable rod away from the clamping block, and the expansion block is movably disposed within the inner groove;

[0024] The rubber ring contracts as it fits into the inner groove.

[0025] The present invention is further configured such that a compression spring is provided at the top end of the cylinder, and the compression spring is sleeved with a threaded rod; a compression sleeve cap is provided at the top end of the compression spring, and the compression sleeve cap is sleeved with the top end of the cylinder.

[0026] The present invention is further configured such that a boss is provided on the outer wall of the cylinder at a position flush with the lower wall of the inner groove;

[0027] The extrusion sleeve cover has a through hole, and the inner wall of the bottom end of the extrusion sleeve cover is also provided with a through hole.

[0028] (III) Beneficial Effects

[0029] Compared with the prior art, the present invention provides a highly stable CNC tool holder structure for low-frequency vibration, which has the following beneficial effects:

[0030] This invention utilizes a tool vibration damping clamping mechanism. During tool installation, the tightening force of the rubber ring drives the clamping block to initially fix the tool inserted into the collet, preventing the tool from sagging during the upward movement of the collet and the worm gear manual screw connection. This ensures the accuracy of the tool installation position. Simultaneously, the compression spring and compression sleeve, combined with the upward movement of the collet and the worm gear screw connection, compress the rubber ring, thereby increasing the clamping force of the clamping block on the tool. This ensures that one end of the tool is clamped by the clamping plate, and the inserted end is clamped by the clamping block, achieving two-point fixation of the tool insertion part. This makes the tool installation more secure. Furthermore, the elasticity of the rubber ring can dampen low-frequency vibrations generated during tool processing, thereby improving processing accuracy. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of a CNC tool holder designed for high stability against low-frequency vibrations.

[0032] Figure 2 This is an exploded structural diagram of a CNC tool holder structure designed for high stability against low-frequency vibrations.

[0033] Figure 3 This is a cross-sectional schematic diagram of a CNC tool holder structure designed for high stability against low-frequency vibrations.

[0034] Figure 4for Figure 3 Enlarged view of point A, showing the structure of the rubber ring expanding and protruding after the cutting tool is inserted.

[0035] Figure 5 This is a schematic diagram of a collet structure for a highly stable CNC tool holder designed for low-frequency vibrations.

[0036] Figure 6 This is a schematic diagram of the initial state of the tool damping clamping component in a high-stability CNC tool holder structure designed for low-frequency vibrations.

[0037] Figure 7 for Figure 6 Enlarged structural diagram at point B.

[0038] Figure 8 This is a schematic diagram of the extrusion sleeve structure for a high-stability CNC tool holder designed for low-frequency vibration.

[0039] In the diagram: 1. Tool holder mechanism; 2. Upper tool holder; 3. Lower tool holder; 4. Drive chamber; 401. Worm chamber; 402. Turbine chamber; 5. Drive assembly; 501. Worm; 502. Turbine; 6. Collet chamber; 7. Collet assembly; 8. Collet; 801. Threaded rod; 802. Cylindrical rod; 803. Clamping plate; 804. Tool slot; 805. Receiving groove; 806. Through hole; 807. Inner groove; 808. Boss; 9. Tool vibration damping clamp; 901. Clamping block; 902. Movable rod; 903. Rubber ring; 904. Wedge surface; 905. Expansion block; 10. Compression spring; 11. Compression sleeve cover; 1101. Through hole; 1102. Guide surface. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0042] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0043] For examples, please refer to Figure 1 - Figure 8A highly stable CNC tool holder structure for low-frequency vibration includes a tool holder mechanism 1, which includes an upper tool holder 2 fixedly connected to the main spindle, and a lower tool holder 3 threadedly connected to the upper tool holder 2.

[0044] The upper tool holder 2 has a drive cavity 4, and the drive cavity 4 is provided with a drive assembly 5;

[0045] The lower tool holder 3 has a collet cavity 6 extending through its axis, and a collet assembly 7 is provided inside the collet cavity 6;

[0046] The collet assembly 7 includes a collet 8 disposed in the collet cavity 6 and screwed to the drive assembly 5, and a tool damping clamping member 9 disposed on the collet 8.

[0047] The collet 8 is used to clamp the cutting tool. Specifically, the drive assembly 5 and the collet 8 are screwed together. The screwing together drives the collet 8 to move upward. The upward collet 8 abuts against the inner wall of the collet cavity 6, thereby retracting and clamping the cutting tool inside.

[0048] However, it is important to note that when the drive assembly 5 is screwed into the collet 8 and the collet 8 is moved upward, it is necessary to ensure that the collet 8 has formed contact friction with the inner wall of the collet cavity 6. If the collet 8 has not formed contact friction with the inner wall of the collet cavity 6 before the drive assembly 5 is screwed into the collet 8, the drive assembly 5 will cause the collet 8 to rotate synchronously when it is operated, which will prevent the collet 8 from being screwed into the collet and moving upward. Therefore, the collet 8 cannot be squeezed and deformed by contact with the collet cavity 6, thus failing to clamp the tool.

[0049] Therefore, the operation of the drive assembly 5 to screw into the collet 8 and move the collet 8 upward is performed only after the collet 8 has already formed contact friction with the inner wall of the collet cavity 6. This contact friction between the collet 8 and the inner wall of the collet cavity 6 is generally achieved by manually rotating the collet 8 to screw into the drive assembly 5 and move it upward. It is important to note the timing of the tool insertion into the collet 8. Because the collet 8 slightly retracts due to its elasticity after contact friction with the inner wall of the collet cavity 6, the timing of the tool insertion into the collet 8 is crucial for easy tool insertion. Before the inner wall of the collet cavity 6 forms contact friction, the clamping between the tool and the collet 8 is entirely achieved through the deformation of the collet 8. Therefore, when the collet 8 does not form contact friction with the inner wall of the collet cavity 6, the insertion between the tool and the collet 8 is a movable insertion. That is, when the collet 8 is manually screwed into the drive assembly 5, it also needs to drive the movable tool together. The installation operation is relatively difficult. If the operation is not proper, the tool will drop when the collet 8 is manually screwed into the drive assembly 5, resulting in the tool not being fully inserted, that is, the lower end of the tool is lower than the set height, thus affecting the machining parameters.

[0050] Meanwhile, after the collet 8 moves upward and is screwed to the drive assembly 5, the collet 8 and the inner wall of the collet cavity 6 come into contact and retract. Since only the expansion end of the collet 8 retracts, it cannot position the deep end of the tool insertion. Moreover, the deep end of the tool insertion and the inner cavity of the collet 8 are generally designed to be fitted together, and there is a gap in the fitting. Therefore, when the tool is being processed, the deep end of the tool will experience low-frequency vibration, which will affect the flatness of the workpiece surface.

[0051] This invention utilizes a tool vibration damping clamping component 9, which is an elastic clamping structure. Initially, its end is located within the cavity of the collet 8 for inserting the tool. Insertion of the tool causes the tool vibration damping clamping component 9 to expand outward. Through its elastic clamping characteristics, the outward expansion force counteracts and clamps the deep end of the tool. This prevents the tool from falling when the collet 8 is manually tightened with the drive assembly 5, allowing it to move upward synchronously with the collet 8. Simultaneously, the clamping of the tool vibration damping clamping component 9 can limit and fix the deep end of the tool, ensuring the stability of the tool. Furthermore, through the elastic characteristics of the tool vibration damping clamping component 9, it can also dampen the tool when low-frequency vibrations occur, thereby reducing the generation of low-frequency vibrations.

[0052] The drive chamber 4 is composed of a worm chamber 401 and a turbine chamber 402, and the worm chamber 401 and the turbine chamber 402 are connected.

[0053] The drive assembly 5 includes a worm 501 disposed in the worm chamber 401 and a turbine 502 disposed in the turbine chamber 402.

[0054] One end of the worm 501 is rotatably mounted on the inner wall of the worm cavity 401 via a bearing, and the other end of the worm 501 is provided with an internal hex wrench groove. The top of the turbine 502 is provided with a rotating shaft, and a bearing is provided on the rotating shaft at the top of the turbine 502. The turbine 502 is rotatably mounted in the turbine cavity 402 via the bearing. The end of the turbine 502 away from the rotating shaft is provided with a threaded hole, and the turbine 502 is screwed and fixed to the collet 8 through the threaded hole.

[0055] The collet 8 includes a threaded rod 801 screwed to the turbine 502, a cylinder 802 disposed at the bottom end of the threaded rod 801, and a clamping plate 803 disposed at the bottom end of the cylinder 802 and arranged in a ring array.

[0056] The clamping plate 803 is an arc-shaped plate, and there is a gap between the multiple sets of clamping plates 803 in the ring array. The diameter of the circle formed by the multiple sets of clamping plates 803 in the ring array near the end of the cylinder 802 is smaller than the diameter of the circle formed by the end of the clamping plates 803 away from the cylinder 802.

[0057] After the threaded rod 801 is screwed to the worm gear 502, rotating the worm gear 501 drives the worm gear 502 to rotate, which in turn causes the threaded rod 801 screwed to the worm gear 502 to move up and down. Since the bottom end of the threaded rod 801 is connected to the cylinder 802 and the clamping plates 803 arranged in a ring, when the threaded rod 801 moves upward, it will drive the clamping plates 803 to move upward. Because the diameter of the circle formed by the multiple sets of clamping plates 803 near the end of the cylinder 802 is smaller than the diameter of the circle formed by the ends of the clamping plates 803 away from the cylinder 802, the clamping plates 803 gradually approach and eventually come into contact with the inner wall of the collet cavity 6 when they move upward. At this time, since the clamping plates 803 are designed as arc plates and there is a gap between the multiple sets of clamping plates 803 in the ring array, when they come into contact with the inner wall of the collet cavity 6, they will deform and generate an inward clamping force, thereby clamping the tool inserted into the collet 8.

[0058] It is worth noting that the teeth of the worm gear 502 have arc-shaped cuts, which increases the contact area when the worm gear 502 and worm 501 mesh and drive, making the driving process smoother and reducing vibration and noise caused by poor meshing. This improves the stability and machining accuracy of the entire tool holder structure. At the same time, the arc-shaped cut design also enhances the load-bearing capacity of the worm gear 502, enabling it to better cope with high-load working environments and extending the service life of the worm gear 502.

[0059] A tool slot 804 is provided at the bottom of the cylinder 802, and the diameter of the tool slot 804 matches the diameter of the circle formed by the multiple sets of clamping plates 803 in the annular array near one end of the cylinder 802.

[0060] The inner wall of the tool slot 804 is provided with a receiving groove 805, and the receiving groove 805 is provided with a through hole 806 in a ring array.

[0061] The tool damping clamping component 9 includes clamping blocks 901 arranged in a ring array within the receiving groove 805, a movable rod 902 disposed on the side wall of the clamping block 901 and movably inserted into the through hole 806, and a rubber ring 903 sleeved on the outside of the cylinder 802.

[0062] When the tool slot 804 is fitted with the tool, and the diameter of the tool slot 804 matches the diameter of the circle formed by the multiple sets of clamping plates 803 in the annular array near the end of the cylinder 802, the tool can be smoothly inserted during insertion. The clamping block 901 is an arc-shaped block, which is arranged in an annular array within the receiving groove 805. It should be noted that the multiple sets of clamping blocks 901 in the annular array are initially close to each other under the tightening of the rubber ring 903, and the diameter formed by the arc-shaped inner wall of the clamping block 901 is smaller than the maximum diameter of the tool insertion, thus forming a pre-clamping force. Therefore, when the tool is inserted, the multiple sets of clamping blocks that are close to each other will be clamped together first. The clamping block 901 expands outward, pushing the rubber ring 903. This causes the rubber ring 903 to be stretched, generating elastic deformation and storing restoring force. When the tool is fully inserted, the restoring force generated by the deformation of the rubber ring 903 acts in the opposite direction on the movable rod 902. The movable rod 902 transmits the force to the clamping block 901, causing the clamping block 901 to tighten inward under the restoring force of the rubber ring. This forms a uniform radial clamping force on the tool surface, thus preventing the tool from sagging when the collet 8 is manually screwed into the drive assembly 5, which could result in the tool not being fully inserted and thus affecting subsequent machining parameters.

[0063] The bottom end of the clamping block 901 is provided with a wedge-shaped surface 904.

[0064] In its initial state, with the rubber ring 903 tightened, the clamping block 901 is still partially located within the receiving groove 805, and the lower end of the wedge-shaped surface 904 is also located within the receiving groove 805. The wedge-shaped surface 904 facilitates the outward expansion and pushing of the clamping block 901 by the tool during insertion. At the same time, the lower end of the wedge-shaped surface 904 is located within the receiving groove 805, preventing the bottom plane of the clamping block 901 from contacting the tool and making it difficult for the tool to be inserted.

[0065] The outer wall of the cylinder 802 is provided with an inner groove 807, and the inner groove 807 is arranged in a ring shape. The inner groove 807 and the through hole 806 are located on the same horizontal line and are connected.

[0066] An expansion block 905 is provided at the end of the movable rod 902 away from the clamping block 901, and the expansion block 905 is movably disposed in the inner groove 807;

[0067] The rubber ring 903 is fitted into the inner groove 807 and shrinks.

[0068] The expansion blocks 905 are arranged in a ring array. When the rubber ring 903 is contracted, the multiple expansion blocks 905 in the ring array fit against the inner wall of the inner groove 807, and the rubber ring 903 is also fitted inside the inner groove 807. By setting the expansion blocks 905, the rubber ring 903 can be expanded more uniformly, and the expanded rubber ring 903 protrudes from the side wall of the cylinder 802.

[0069] A compression spring 10 is provided at the top of the cylinder 802, and the compression spring 10 is sleeved with the threaded rod 801. A compression sleeve 11 is provided at the top of the compression spring 10, and the compression sleeve 11 is sleeved with the top of the cylinder 802.

[0070] After the cutting tool is inserted into the collet 8, the rubber ring 903 expands and protrudes from the side wall of the cylinder 802. When the collet 8 is screwed into the turbine 502, the collet 8 moves upward, causing the compression spring 10 to push the compression sleeve 11 upward to abut the bottom of the turbine 502. Then the compression spring 10 is gradually compressed, and the collet 8 drives the protruding rubber ring 903 to move upward and gradually approach the lower end of the compression sleeve 11, forming a compression with the lower end of the compression sleeve 11. The rubber ring 903 deforms under the action of the mutual compression force, thereby increasing the clamping force of the clamping block 901 on the cutting tool. Furthermore, through the material properties of the rubber ring 903 itself, the low-frequency vibration of the clamped cutting tool is damped.

[0071] In summary, during the screw connection process between the collet 8 and the turbine 502, the tool damping clamping component 9 produces different functional effects on the tool. During the initial insertion, it can initially limit the tool, making it easy to manually screw the collet and the turbine 502 together. Then, the worm gear 501 drives the turbine 502 to rotate, so that when the turbine 502 and the collet 8 are screwed together, the collet 8 moves upward through the screw connection, thereby squeezing the rubber ring 903, which increases the clamping force on the tool and ensures that the tool is stably clamped. In addition, during processing, the rubber ring 903 can also provide the tool with a certain amount of shock absorption and buffering.

[0072] A boss 808 is provided on the outer wall of the cylinder 802, which is flush with the lower wall of the inner groove 807.

[0073] The extrusion sleeve 11 has a through hole 1101, and the inner wall of the bottom end of the extrusion sleeve 11 is provided with a through hole 1101.

[0074] The diameter of the boss 808 matches the inner diameter of the collet cavity 6. The boss 808 is designed to provide support for the bottom of the protruding rubber ring 903, so that the rubber ring 903 will not detach from the horizontal position of the inner groove 807 when the extrusion sleeve cover 11 is extruded. The through hole 1101 is used for the threaded rod 801 to pass through, so that the threaded rod 801 of the collet 8 can be properly screwed to the bottom of the turbine 502. The diameter of the extrusion sleeve cover 11 matches the inner diameter of the collet cavity 6. With the through hole 1101, when the collet 8 moves the rubber ring 903 and the extrusion sleeve cover 11 close to each other for extrusion, the through hole 1101 at the bottom of the extrusion sleeve cover 11 first abuts against the rubber ring 903. With the through hole 1101, the rubber ring 903 is pushed into the inner groove 807, so that the extrusion recovery force generated by the rubber ring 903 is greater, thereby making the tool more stably fixed.

[0075] Working principle: When installing the tool, first insert the tool into the collet 8. After the tool enters the tool slot 804 in the collet 8, the multiple sets of clamping blocks 901 in the annular array are pushed radially outward, thereby expanding the rubber ring 903 through the movable rod 902 and the expansion block 905. After being expanded and stretched, the rubber ring 903 has a restoring force, which initially clamps the tool, preventing the tool from falling when the collet 8 and the turbine 502 are screwed together. At this time, the rubber ring 903 protrudes from the outer wall of the cylinder 802. Then, manually rotate the collet 8. The collet 8 is screwed together with the turbine 502 through the threaded rod 801 and produces an upward movement. When the collet 8 moves upward, the lower end of its clamping plate 803 gradually approaches and finally engages with the collet cavity 6. When the inner wall comes into contact with the material, the manual tightening ends. Then, the worm 501 is turned with a hex wrench, which drives the turbine 502 to rotate, thereby tightening the turbine 502 and the collet 8. This causes the collet 8 to continue moving upward, which in turn causes the clamping plate 803 to move upward, causing the clamping plate 803 to further retract inward, thus clamping and fixing the tool.

[0076] When the collet 8 moves upward, it drives the compression spring 10 to push the compression sleeve cover 11 upward and abut against the bottom of the turbine 502. Then, the compression spring 10 is gradually compressed, and the collet 8 drives the protruding rubber ring 903 to move upward and gradually approach the lower end of the compression sleeve cover 11. During the approach process, the through hole 1101 at the bottom of the compression sleeve cover 11 first abuts against the rubber ring 903. Through the setting of the through hole 1101, the rubber ring 903 is pushed into the inner groove 807, thereby making the compression recovery force generated by the rubber ring 903 greater, thus making the tool more stably fixed.

[0077] Of all the solutions mentioned above, those involving the connection between two components can be selected according to the actual situation, such as welding, bolt and nut connection, bolt or screw connection, or other known connection methods, which will not be elaborated here. For all the fixed connections mentioned above, welding is preferred. Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A highly stable CNC tool holder structure for low-frequency vibration, characterized by: include, The tool holder mechanism (1) includes an upper tool holder (2) fixedly connected to the main spindle of the host machine, and a lower tool holder (3) threadedly connected to the upper tool holder (2). The upper tool holder (2) has a drive cavity (4) and a drive assembly (5) is provided in the drive cavity (4). The lower tool holder (3) has a collet cavity (6) extending through its axis, and a collet assembly (7) is provided inside the collet cavity (6). The collet assembly (7) includes a collet (8) disposed in the collet cavity (6) and screwed to the drive assembly (5), and a tool damping clamping member (9) disposed on the collet (8).

2. The highly stable CNC tool holder structure for low-frequency vibration according to claim 1, characterized in that: The drive chamber (4) is composed of a worm chamber (401) and a turbine chamber (402), and the worm chamber (401) and the turbine chamber (402) are connected. The drive assembly (5) includes a worm (501) disposed in the worm cavity (401) and a turbine (502) disposed in the turbine cavity (402).

3. The highly stable CNC tool holder structure for low-frequency vibration according to claim 2, characterized in that: The collet (8) includes a threaded rod (801) screwed to the turbine (502), a cylinder (802) disposed at the bottom end of the threaded rod (801), and a clamping plate (803) disposed at the bottom end of the cylinder (802) and arranged in a ring array.

4. The highly stable CNC tool holder structure for low-frequency vibration according to claim 3, characterized in that: The clamping plate (803) is an arc-shaped plate, and there is a gap between the multiple sets of clamping plates (803) in the ring array. The diameter of the circle formed by the multiple sets of clamping plates (803) in the ring array near the end of the cylinder (802) is smaller than the diameter of the circle formed by the end of the clamping plates (803) away from the cylinder (802).

5. The highly stable CNC tool holder structure for low-frequency vibration according to claim 4, characterized in that: The bottom end of the cylinder (802) is provided with a tool slot (804), and the diameter of the tool slot (804) matches the diameter of the circle formed by the multiple sets of clamps (803) in the annular array near one end of the cylinder (802).

6. The highly stable CNC tool holder structure for low-frequency vibration according to claim 5, characterized in that: The inner wall of the tool slot (804) is provided with a receiving groove (805), and the receiving groove (805) is provided with a through hole (806) in a ring array. The tool damping clamp (9) includes clamping blocks (901) arranged in a ring array in the receiving groove (805), a movable rod (902) disposed on the side wall of the clamping block (901) and movably inserted into the through hole (806), and a rubber ring (903) sleeved on the outside of the cylinder (802).

7. The highly stable CNC tool holder structure for low-frequency vibration according to claim 6, characterized in that: The bottom end of the clamping block (901) is provided with a wedge-shaped surface (904).

8. The highly stable CNC tool holder structure for low-frequency vibration according to claim 7, characterized in that: The outer wall of the cylinder (802) is provided with an inner groove (807), and the inner groove (807) is arranged in a ring shape. The inner groove (807) and the through hole (806) are located on the same horizontal line and are connected. An expansion block (905) is provided at one end of the movable rod (902) away from the clamping block (901), and the expansion block (905) is movably disposed in the inner groove (807); The rubber ring (903) is fitted into the inner groove (807) and shrinks.

9. A highly stable CNC tool holder structure for low-frequency vibration according to claim 8, characterized in that: A compression spring (10) is provided at the top of the cylinder (802), and the compression spring (10) is sleeved with the threaded rod (801). A compression sleeve cover (11) is provided at the top of the compression spring (10), and the compression sleeve cover (11) is sleeved with the top of the cylinder (802).

10. A highly stable CNC tool holder structure for low-frequency vibration according to claim 9, characterized in that: The outer wall of the cylinder (802) is flush with the lower wall of the inner groove (807) and a boss (808) is provided. The extrusion sleeve (11) has a through hole (1101) and the inner wall of the bottom end of the extrusion sleeve (11) is provided with a through hole (1101).

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