A passive damping vibration reduction device for a boring bar extension
By incorporating a triple energy dissipation mechanism—comprising an oscillator, an elastic block, and damping fluid—within the extended rod of the boring tool, the problem of poor reliability in existing damping and vibration reduction devices is solved. This achieves efficient absorption and dissipation of vibration energy, thereby improving the service life and machining accuracy of the boring tool.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIER MACHINE TOOL GROUP
- Filing Date
- 2025-06-26
- Publication Date
- 2026-07-24
AI Technical Summary
Existing external damping and vibration reduction devices mostly use a single damping element, resulting in poor reliability and difficulty in effectively absorbing and dissipating the vibration energy of the boring bar extension rod, which affects the machining quality and service life.
A triple energy dissipation mechanism consisting of an oscillator, an elastic block, and a damping fluid within a cylindrical shell is employed. Vibration energy is transferred and converted into heat energy through dynamic vibration absorption and viscous shear field, forming a secondary mass system to absorb and dissipate vibration.
This significantly improves vibration reduction, ensures the stability and machining accuracy of the boring bar extension rod, and avoids the structural complexity and high cost issues of existing devices.
Smart Images
Figure CN224550693U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of boring bar vibration reduction technology, specifically to a passive damping vibration reduction device for extending the boring bar. Background Technology
[0002] During machining, cutting tools, especially boring tools with extended handles, are often affected by various factors such as cutting forces, machine tool vibration, and tool resonance, resulting in significant tool vibration. This vibration not only degrades the surface finish but also affects tool life and machining accuracy. Particularly in precision machining, the vibration of boring tools with extended handles often becomes a major factor affecting machining quality.
[0003] To address this issue, damping and vibration reduction devices are typically installed inside the boring bar extension rod to reduce vibration. However, this structure often affects the rigidity and bending strength of the tool, and it requires significant modifications to the boring bar structure, resulting in a complex structure and high manufacturing costs.
[0004] To address this issue, external damping vibration reduction devices have emerged in the prior art. However, most existing external damping vibration reduction devices use a single damping element, resulting in a single vibration energy dissipation mechanism. Furthermore, the reliability of the damping element is relatively poor. For example, when using a particle damper, the metal particles are prone to deposition due to vibration, significantly reducing the vibration reduction effect. Therefore, existing external damping vibration reduction devices have poor vibration reduction performance, cannot effectively absorb and dissipate vibration energy, and are difficult to achieve optimal vibration reduction results. Utility Model Content
[0005] To address the technical problem that existing external damping vibration reduction devices mostly use a single damping element and have poor reliability, resulting in poor vibration reduction effect, inability to effectively absorb and dissipate vibration energy, and difficulty in achieving optimal vibration reduction effect, this utility model provides a passive damping vibration reduction device for extending the tool holder of a boring tool.
[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0007] A passive damping vibration reduction device for extending the tool holder of a boring bar includes a housing, which is a cylindrical structure. One end of the housing is closed, and the other end is open and connected to an end cap. The closed end of the housing and the end cap form a cylindrical sealed cavity. Two identical elastic blocks are provided in the sealed cavity, and the two elastic blocks are respectively fixed to the two ends of the sealed cavity. A cylindrical oscillator is fixedly connected between the two elastic blocks. The oscillator is coaxially arranged with the housing, and an annular gap is provided between the outer peripheral surface of the oscillator and the inner peripheral surface of the housing. The entire space in the sealed cavity, except for the solid parts of the elastic blocks and the oscillator, is filled with damping fluid.
[0008] In the above structural design, the oscillator is connected to the shell via an elastic block, forming a secondary mass system. Its natural frequency can be close to or differ from the vibration frequency of the extended boring bar by a certain range. Through dynamic vibration absorption, the vibrational energy of the extended boring bar is transferred to the damping device and dissipated. Furthermore, the oscillator and the damping fluid form a viscous shear field. When the boring bar vibration is transmitted to the shell, the oscillator vibrates under the support of the elastic block, and the viscous damping fluid dissipates energy due to shear flow. Simultaneously, the elastic block has high internal friction characteristics, converting vibrational energy into heat energy through internal friction. Therefore, this application forms a triple energy dissipation mechanism, significantly improving the energy dissipation and vibration reduction effect.
[0009] As a preferred implementation of a passive damping vibration reduction device for extending the tool holder of a boring bar, the elastic block is a columnar ring structure, and the oscillator includes a main body section. Both ends of the main body section are connected to a reduced diameter section. The outer diameter of the reduced diameter section is smaller than the outer diameter of the main body section, and the outer diameter of the reduced diameter section is equal to the inner diameter of the through hole of the elastic block. The reduced diameter section is inserted into the through hole of the elastic block.
[0010] The above structural design employs an interference fit between the reduced-diameter section and the through-hole of the elastic block to ensure the coaxiality of the oscillator and the shell, thus avoiding additional bending moments caused by non-coaxial vibration. The ring structure of the elastic block provides radial elastic support, allowing the oscillator to vibrate relative to the shell to excite the damping fluid to dissipate energy, while limiting structural collisions caused by excessive amplitude.
[0011] In a preferred implementation of a passive damping vibration reduction device for extending the tool holder of a boring bar, the lengths of the two reduced diameter sections are equal, and the length of the oscillator is shorter than the axial length of the sealed cavity.
[0012] The above structural design ensures uniform force distribution on the oscillator by using equal-length reduced-diameter sections, avoiding uneven flow of damping fluid caused by eccentric vibration. The oscillator length is shorter than the axial length of the cavity, with a reserved axial clearance to prevent the oscillator from colliding with the end face of the housing during high-frequency vibration.
[0013] As a preferred implementation of a passive damping vibration reduction device for extending the tool holder of a boring bar, the oscillator has a central hole, which is coaxially arranged with the oscillator and passes through the oscillator along the axial direction of the oscillator.
[0014] With the above structural design, the axial gaps between the two ends of the oscillator and the shell are connected to the central hole, forming a flow channel for the damping fluid. The central hole is relatively small, which can slow down the flow of the damping fluid, prevent the oscillator from vibrating too fast, and achieve a better vibration reduction effect.
[0015] In a preferred embodiment of a passive damping vibration reduction device for extending the tool holder of a boring bar, the two ends of the main body section abut against the end faces of two elastic blocks respectively.
[0016] With the above structural design, the end face of the main body section abuts against the elastic block, and the vibration energy can be directly transmitted through the end face, resulting in better energy transmission and thus improving the vibration reduction effect while preventing the oscillator from loosening.
[0017] In a preferred embodiment of a passive damping vibration reduction device for extending the tool holder of a boring bar, the outer peripheral surface of the elastic block abuts against the inner peripheral surface of the housing, one end face of the elastic block located at the closed end of the housing abuts against the inner end face of the closed end of the housing, and one end face of the elastic block located at the open end of the housing abuts against the inner end face of the end cap.
[0018] With the above structural design, the connection area between the elastic block and the shell is larger, resulting in better energy transfer.
[0019] In a preferred embodiment of a passive damping vibration reduction device for extending the tool holder of a boring bar, the housing, the sealed cavity, the elastic block, and the oscillator are all cylindrical.
[0020] The above-mentioned structural design is easy to process, has low cost, and provides stable and uniform energy dissipation.
[0021] As a preferred implementation of a passive damping vibration reduction device for extending the tool holder of a boring tool, the end cover includes a cover body, one end face of which is coaxially connected to a cylindrical body, the outer circumferential surface of the cylindrical body is provided with external threads, the inner circumferential surface of the open end of the shell is provided with internal threads, and the cylindrical body is threadedly connected to the open end of the shell.
[0022] The above structural design facilitates disassembly.
[0023] In a preferred embodiment of a passive damping vibration reduction device for extending the tool holder of a boring bar, a connecting shaft is connected to the center of the outer end face of the closed end of the housing, and the outer circumferential surface of the connecting shaft is provided with an external thread.
[0024] Using the above structural design, the connecting shaft can be used to connect the extended tool holder of the boring tool.
[0025] In a preferred implementation of a passive damping vibration reduction device for extending the tool holder of a boring bar, the elastic block is made of rubber.
[0026] By adopting the above structural scheme, the hysteresis damping effect of rubber and the viscous damping of the damping fluid complement each other, thus broadening the vibration reduction frequency band.
[0027] The beneficial effects of this utility model include:
[0028] 1. This application establishes a triple energy dissipation mechanism, significantly improving energy dissipation and vibration reduction effects. The first energy dissipation mechanism involves the oscillator being connected to the shell via an elastic block, forming a secondary mass system. Its natural frequency can be close to or differ from the vibration frequency of the extended boring bar by a certain range. Through dynamic vibration absorption, the vibration energy of the extended boring bar is transferred to the vibration damping device and dissipated. The second energy dissipation mechanism involves the oscillator and damping fluid forming a viscous shear field. When the boring bar vibration is transmitted to the shell, the oscillator vibrates under the support of the elastic block, and the viscous damping fluid dissipates energy due to shear flow. The third energy dissipation mechanism involves the elastic block having high internal friction characteristics, which can convert vibration energy into heat energy through internal friction.
[0029] 2. The damping fluid fills all the space except for the oscillator and the elastic block, avoiding the deposition problem of existing particulate dampers and ensuring long-term stability of damping characteristics. Attached Figure Description
[0030] To more clearly illustrate the technical solution of this utility model, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0031] Figure 1 This is a cross-sectional structural schematic diagram of a passive damping vibration reduction device for extending the tool holder of a boring bar, according to a specific embodiment of this utility model.
[0032] Figure 2 This is a schematic diagram showing the usage state of a passive damping vibration reduction device for extending the tool holder of a boring bar, according to a specific embodiment of this utility model.
[0033] Figure 3 This is a cross-sectional structural diagram of the oscillator in a specific embodiment of this utility model;
[0034] Figure 4 This is a cross-sectional structural diagram of the elastic block in a specific embodiment of the present invention.
[0035] List of components and reference numerals:
[0036] 1. Shell; 2. End cap; 21. Cover body; 22. Cylinder body; 3. Elastic block; 31. Anti-slip texture; 4. Vibrator; 41. Main body section; 42. Reduced diameter section; 43. Center hole; 44. Circular convex ring; 5. Annular gap; 6. Connecting shaft; 7. Boring tool extended shank. Detailed Implementation
[0037] To make the objectives, features, and advantages of this utility model more apparent and understandable, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0038] Reference Figure 1-2 This embodiment proposes a passive damping vibration reduction device for an extended boring bar, comprising a housing 1, which is cylindrical in shape. One end of the housing 1 is closed, and the other end is open and connected to an end cap 2. The end cap 2 includes a cover body 21, and a cylindrical cylinder 22 is coaxially connected to one end face of the cover body 21. The outer circumferential surface of the cylinder 22 is provided with external threads, and the inner circumferential surface of the open end of the housing 1 is provided with internal threads. The cylinder 22 is threadedly connected to the open end of the housing 1. The pitch between the external thread groove of the cylinder 22 and the internal thread groove of the open end of the housing 1 is 1.5 mm, and the thread profile is triangular to ensure the stability of the connection between the end cap 2 and the housing 1 and the ease of disassembly. A connecting shaft 6 is connected to the center of the outer end face of the closed end of the housing 1. The outer circumferential surface of the connecting shaft 6 is provided with external threads. The connecting shaft 6 is used for threaded connection to the end of the extended boring bar, which can be fixed to the machine tool.
[0039] A cylindrical, sealed cavity is formed between the closed end of the housing 1 and the end cap 2. Two identical elastic blocks 3, made of rubber, are disposed within this cavity. Both elastic blocks 3 are cylindrical and annular in structure. The two elastic blocks 3 are fixed to both ends of the sealed cavity. The outer circumferential surface of the elastic block 3 abuts against the inner circumferential surface of the housing 1. One end face of the elastic block 3 located at the closed end of the housing 1 abuts against the inner end face of the closed end of the housing 1, and one end face of the elastic block 3 located at the open end of the housing 1 abuts against the inner end face of the end cap 2. The rubber elastic blocks 3 possess high internal friction characteristics, enabling them to convert vibrational energy into heat energy through internal friction.
[0040] A cylindrical oscillator 4 is fixedly connected between two elastic blocks 3. The oscillator 4 is coaxially arranged with the housing 1, and an annular gap 5 is provided between the outer circumferential surface of the oscillator 4 and the inner circumferential surface of the housing 1. The oscillator 4 includes a main body section 41, and a reduced-diameter section 42 is connected to the center of each end of the main body section 41. The two reduced-diameter sections 42 are of equal length, and their outer diameters are smaller than the outer diameter of the main body section 41 and larger than the inner diameter of the through hole of the elastic block 3. The two ends of the main body section 41 abut against the end faces of the two elastic blocks 3, and the reduced-diameter sections 42 are inserted into the through holes of the elastic blocks 3. The axial length of the oscillator 4 is shorter than the axial length of the sealed cavity. The oscillator 4 has a central hole 43, which is coaxially arranged with the oscillator 4 and extends through the oscillator 4 along its axial direction. The central hole 43 is relatively small, which can slow down the flow of damping fluid and achieve a better vibration reduction effect. The oscillator 4 is connected to the outer shell through the elastic block 3, forming a secondary mass system. Its natural frequency can be close to or different from the vibration frequency of the boring bar extension bar 7 by a certain range. Through dynamic vibration absorption, the vibration energy of the boring bar extension bar 7 is transferred to the vibration damping device and dissipated.
[0041] The entire space within the sealed cavity, except for the solid portions of elastic block 3 and oscillator 4, is filled with damping fluid. (Refer to...) Figure 1 The annular gap 5 between the outer circumferential surface of the oscillator 4 and the inner circumferential surface of the housing 1, the central hole 43 of the oscillator 4, and the gaps between the two ends of the oscillator 4 and the closed end and end cap 2 of the housing 1, respectively, are all filled with damping fluid. The damping fluid increases the viscous damping of the device, restricts the rapid movement of the oscillator 4, and further reduces the vibration amplitude.
[0042] Reference Figure 3 The outer circumferential surface of the main body section 41 of the oscillator 4 may have several circular protrusions 44. The outer diameter of the circular protrusions 44 is smaller than the inner diameter of the shell 1. The several circular protrusions 44 are evenly spaced along the axial direction of the main body section 41. The circular protrusions 44 are used to increase the contact area between the oscillator 4 and the damping fluid and improve the damping and vibration reduction effect.
[0043] Reference Figure 4 The inner wall of the through hole of the elastic block 3 can be provided with several anti-slip textures 31. The anti-slip textures 31 are all arranged along the axial direction of the vibrator 4. The anti-slip textures 31 are used to increase the friction between the vibrator 4 and the narrowed section 42 of the vibrator 4, and prevent the vibrator 4 from rotating relative to the elastic block 3.
[0044] For different working conditions, the natural frequency of the passive damping vibration reduction device in this embodiment needs to be close to the vibration frequency of the extended tool bar 7 of the boring tool. Therefore, the natural frequency of the passive damping vibration reduction device needs to be adjusted.
[0045] In this embodiment, the natural frequency of the passive damping vibration reduction device can be adjusted by adjusting the mass of the oscillator 4, the damping coefficient of the damping fluid, and the hardness of the elastic block 3.
[0046] The mass of the oscillator 4 can be adjusted by changing its material or hollowing out non-critical areas. The damping coefficient of the damping fluid can be adjusted by changing the size of the central hole 43 of the oscillator 4, the through-hole size of the elastic block 3, and the viscosity of the damping fluid. Figure 1 As shown, the size of the central hole 43 is D, and the size of the through hole of the elastic block 3 is A. The hardness of the elastic block 3 can be adjusted by changing the type of rubber material.
[0047] Working principle:
[0048] When the extended tool holder 7 of the boring tool vibrates during the cutting process due to the cutting force or machine tool vibration, the vibration is transmitted to the housing 1 through the connecting shaft 6, and the vibration energy is transmitted into the sealed cavity in a combined axial and radial form.
[0049] The vibration of the housing 1 drives the elastic blocks 3 at both ends to move synchronously. The elastic blocks 3 drive the oscillator 4 to reciprocate relative to the housing 1 through the reduced diameter section 42. At this time, the secondary mass system formed by the oscillator 4 and the housing 1 generates a natural frequency. This natural frequency is close to the vibration frequency of the boring tool. The vibration energy of the extended tool bar 7 of the boring tool is transferred to the passive damping vibration reduction device in this specific embodiment through the principle of resonance absorption.
[0050] When the oscillator 4 vibrates, the damping fluid generates shear flow, converting kinetic energy into heat energy. The damping fluid can flow in the annular gap 5 between the outer circumferential surface of the oscillator 4 and the inner circumferential surface of the shell 1, or it can flow in the central hole 43 of the oscillator 4.
[0051] The elastic block 3 made of rubber consumes energy due to intermolecular friction during deformation, and can convert vibrational energy into heat energy.
[0052] In summary, in the passive damping vibration reduction device of this specific embodiment, the vibration energy is gradually dissipated through the transmission path of the extended tool bar 7, housing 1, elastic block 3, oscillator 4, and damping fluid, ultimately reducing the amplitude of the tool tip and meeting the requirements of precision machining.
[0053] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A passive damping vibration reduction device for extending the tool holder of a boring bar, comprising a housing (1), characterized in that, The shell (1) is a columnar structure. One end of the shell (1) is a closed end, and the other end is an open end connected to an end cap (2). The closed end of the shell (1) and the end cap (2) form a columnar closed cavity. Two identical elastic blocks (3) are provided in the sealed cavity. The two elastic blocks (3) are fixed at both ends of the sealed cavity respectively. A columnar vibrator (4) is fixedly connected between the two elastic blocks (3). The vibrator (4) is coaxially arranged with the shell (1). An annular gap (5) is provided between the outer circumferential surface of the vibrator (4) and the inner circumferential surface of the shell (1). The entire space in the sealed cavity, except for the solid parts of the elastic block (3) and the oscillator (4), is filled with damping fluid.
2. The passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 1, characterized in that, The elastic block (3) is a columnar ring structure. The oscillator (4) includes a main body section (41). Both ends of the main body section (41) are connected to a reduced diameter section (42). The outer diameter of the reduced diameter section (42) is smaller than the outer diameter of the main body section (41). The outer diameter of the reduced diameter section (42) is larger than the inner diameter of the through hole of the elastic block (3). The reduced diameter section (42) is inserted into the through hole of the elastic block (3).
3. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 2, characterized in that, The two reduced diameter sections (42) are of equal length, and the length of the oscillator (4) is shorter than the axial length of the sealed cavity.
4. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 3, characterized in that, The oscillator (4) has a central hole (43), which is coaxial with the oscillator (4) and passes through the oscillator (4) along the axial direction of the oscillator (4).
5. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 2, characterized in that, The two ends of the main body segment (41) abut against the end faces of the two elastic blocks (3) respectively.
6. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 2, characterized in that, The outer peripheral surface of the elastic block (3) abuts against the inner peripheral surface of the shell (1), one end face of the elastic block (3) located at the closed end of the shell (1) abuts against the inner end face of the closed end of the shell (1), and one end face of the elastic block (3) located at the open end of the shell (1) abuts against the inner end face of the end cap (2).
7. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 1, characterized in that, The shell (1), the sealed cavity, the elastic block (3) and the oscillator (4) are all cylindrical.
8. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 7, characterized in that, The end cap (2) includes a cap body (21), and a cylindrical cylinder (22) is coaxially connected to one end face of the cap body (21). The outer circumferential surface of the cylinder (22) is provided with an external thread, and the inner circumferential surface of the open end of the shell (1) is provided with an internal thread. The cylinder (22) is threadedly connected to the open end of the shell (1).
9. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 1, characterized in that, A connecting shaft (6) is connected to the center of the outer end face of the closed end of the housing (1), and the outer circumferential surface of the connecting shaft (6) is provided with an external thread.
10. A passive damping vibration reduction device for extending the tool holder of a boring bar according to claim 1, characterized in that, The elastic block (3) is made of rubber.