Part clamping end fluid viscous damping damping tool and amplitude optimization design method

Abstract

The present application relates to the technical field of part processing damping, and discloses a part clamping end fluid viscous damping damping tool and an amplitude optimization design method.The part clamping end fluid viscous damping damping tool comprises a base assembly, a clamping assembly, a first leaf spring and a second leaf spring, and an attached fluid viscous damper.The clamping assembly comprises a fixed platform and a movable platform, the movable platform is adjustably connected to the fixed platform, and the movable platform and the fixed platform jointly form a clamping space for clamping a part to be processed.The one end of the first leaf spring and the one end of the second leaf spring are respectively connected to the fixed platform, and the other end of the first leaf spring and the other end of the second leaf spring are respectively connected to the base assembly.When the fixed platform vibrates, the mass block and the damper shell produce relative movement, so that the liquid damping medium flows through the annular damping gap and dissipates vibration energy.The attached fluid viscous damper can be used to dissipate vibration energy, and the probability of vibration or flutter of the part to be processed during the cutting process can be reduced.

Description

Technical Field

[0001] This invention relates to the field of vibration control and process equipment technology in cutting processes, specifically to a fluid viscosity damping vibration reduction fixture and amplitude optimization design method for the clamping end of a part. Background Technology

[0002] In aerospace, precision equipment, and other fields, some parts to be machined are characterized by small size, low stiffness, complex structure, or variable dynamic characteristics. During milling and other cutting processes, they are easily subjected to periodic cutting force excitation, resulting in vibration. This type of vibration is especially prone to develop into machining chatter for low-stiffness parts such as small thin-walled parts, curved thin-walled parts, and blade-like parts.

[0003] Existing vibration reduction methods for machining thin-walled parts mainly include optimizing cutting parameters, increasing clamping stiffness, adding damping materials to the part surface, or installing dynamic vibration absorption devices. Among these, optimizing cutting parameters usually sacrifices material removal efficiency; simply increasing clamping stiffness is insufficient to fully suppress local modal vibrations in thin-walled areas; while directly installing dampers or adding mass blocks to the part surface can improve damping, for small curved thin-walled parts, it easily occupies machining space, causes tool interference, and may cause part deformation due to additional loads or clamping effects.

[0004] Furthermore, existing dynamic vibration-absorbing fixtures often form tuned vibration-absorbing systems using structures such as leaf springs and mass blocks to alter the dynamic response of the machined parts. However, these structures typically use mass blocks to support the parts or adjust the frequency by regulating the equivalent suspension length of the leaf springs. Their primary vibration reduction mechanism leans towards dynamic vibration absorption. For scenarios involving small, thin-walled parts with limited space at the clamping end, complex machining paths, or the need for additional energy-dissipating damping, structural adaptability and energy dissipation capacity remain insufficient. Existing parameter design methods for vibration-absorbing fixtures are mostly designed for traditional dynamic vibration absorbers or isolators. Their structural models and optimization criteria are difficult to directly apply to vibration-absorbing fixtures that are positioned at the part clamping end and simultaneously feature leaf spring elastic supports and attached fluid viscous dampers. Current technology lacks system parameter design methods for this type of vibration-absorbing fixture, making it difficult to rationally determine the mass, stiffness, and damping parameters of the fixture based on the dynamic characteristics of the workpiece.

[0005] Therefore, it is necessary to provide a fluid viscous damping vibration reduction fixture and amplitude optimization design method at the part clamping end, so that the fluid viscous damping vibration reduction fixture at the part clamping end can determine the optimal stiffness and optimal damping parameters of the vibration reduction fixture according to the dynamic characteristics of the part to be processed, while avoiding tool interference and additional deformation of the part, thereby reducing machining vibration and improving cutting stability. Summary of the Invention

[0006] The purpose of this invention is to provide a fluid viscosity damping and vibration reduction fixture and amplitude optimization design method for the clamping end of a part, so as to solve the problem that the existing parts to be processed are prone to vibration or chatter during the cutting process.

[0007] To achieve the above objectives, a first aspect of the present invention provides a fluid viscosity damping and vibration reduction fixture for use between a machine tool and the clamping end of a part to be processed, comprising: Base assembly; The clamping assembly includes a fixed platform and a movable platform, wherein the movable platform is tunably connected to the fixed platform and together with the fixed platform forms a clamping space for clamping the part to be processed; A first leaf spring and a second leaf spring are respectively disposed on opposite sides of the fixed platform. One end of the first leaf spring and one end of the second leaf spring are respectively connected to the fixed platform, and the other ends of the first leaf spring and the second leaf spring are respectively connected to the base assembly to provide elastic support for the fixed platform and guide the fixed platform to move relative to the base assembly; and An attached fluid viscous damper includes a damper housing fixed to the side of a fixed platform, a mass block movably housed within the damper housing, and a liquid damping medium filled within the damper housing; an annular damping gap is formed between the outer cylindrical surface of the mass block and the inner cylindrical surface of the damping cavity of the damper housing; when the fixed platform vibrates, the mass block and the damper housing move relative to each other, causing the liquid damping medium to flow through the annular damping gap and dissipate vibration energy.

[0008] The fluid viscosity damping vibration reduction fixture at the part clamping end of this invention, by setting an attached fluid viscosity damper, can dissipate vibration energy and reduce the probability of vibration or chatter of the part to be processed during the cutting process.

[0009] The part clamping end fluid viscosity damping vibration reduction fixture according to an embodiment of the present invention also has the following additional technical features: Furthermore, the base assembly includes a first base and a second base disposed opposite to each other; the first base is provided with a first clamping part, and the second base is provided with a second clamping part, the first clamping part and the second clamping part being used to clamp the fixed platform.

[0010] Furthermore, the movable platform includes a first connecting arm and a second connecting arm, the first connecting arm and the second connecting arm respectively having a first adjustment groove and a second adjustment groove, the first adjustment groove and the second adjustment groove respectively having an opening; fasteners pass through the first adjustment groove and the second adjustment groove respectively and are connected to the fixed platform to adjust the position of the movable platform relative to the fixed platform.

[0011] Furthermore, the first leaf spring and the second leaf spring are arranged parallel to each other and symmetrically with respect to the fixed platform, so as to guide the fixed platform to move along the flexible direction of the first leaf spring and the second leaf spring.

[0012] Furthermore, the first leaf spring and the second leaf spring are respectively provided with waist-shaped adjustment holes extending along their own length direction; fasteners pass through the waist-shaped adjustment holes of the first leaf spring to connect the first leaf spring to the base assembly, and fasteners pass through the waist-shaped adjustment holes of the second leaf spring to connect the second leaf spring to the base assembly.

[0013] Furthermore, the first leaf spring is fixed to the fixed platform by a first upper clamping strip, and the first leaf spring is fixed to the base assembly by a first lower clamping strip; and / or, the second leaf spring is fixed to the fixed platform by a second upper clamping strip, and the second leaf spring is fixed to the base assembly by a second lower clamping strip.

[0014] Furthermore, the damper housing is provided with a mounting flange, which is fixed to the damper mounting surface of the fixed platform by fasteners; the open end of the damper housing is provided with an end cap that is sealed to the damper housing.

[0015] A second aspect of this invention provides an amplitude optimization design method, which can be implemented using a fluid viscous damping vibration reduction fixture at the clamping end of a part. This method is used to optimize the amplitude of the fluid viscous damping vibration reduction fixture at the clamping end of the part. The amplitude optimization design method includes: Obtain the equivalent mass of the part to be processed. Equivalent stiffness and frequency response function; The vibration damping fixture is equivalent to having an equivalent mass. Equivalent stiffness and equivalent damping A single-degree-of-freedom system; A two-degree-of-freedom coupled system is established, consisting of the part to be processed and the fluid viscous damping vibration reduction device at the clamping end of the part. The optimization objective is to minimize the maximum amplitude of the frequency response function of the part to be processed within the target frequency range.

[0016] in, Let be the frequency response function of the part to be processed. For the target frequency range; Based on the optimized equivalent stiffness and equivalent damping The structural parameters of the first leaf spring, the second leaf spring, and the attached fluid viscosity damper are determined.

[0017] Furthermore, make the quality ratio stiffness ratio The optimal stiffness ratio is determined as follows: :

[0018] : Take the unique positive real root of the equation, where, This represents the optimal stiffness ratio.

[0019] Furthermore, after determining the optimal stiffness ratio, the square of the dimensionless frequency is denoted as... The square of the damping ratio is denoted as Based on the two fixed points of the two-degree-of-freedom coupled system Determine the square value of the damping ratio respectively : in, ;in, and It is an equation The two roots; The optimal damping ratio is determined according to the following formula:

[0020] The optimal equivalent damping is determined according to the following formula:

[0021] The effective deformation lengths of the first and second leaf springs are adjusted according to the optimal stiffness ratio, and the viscosity of the liquid damping medium and / or the size of the annular damping gap are determined according to the optimal equivalent damping.

[0022] Compared with the prior art, the present invention has at least the following beneficial effects: First, the present invention places the fluid viscosity damping and vibration reduction fixture at the clamping end of the part to be processed at the clamping end of the part, rather than directly on the processing surface of the part. This can reduce the occupation of processing space and reduce the risk of interference with the tool. It is especially suitable for cutting small parts, curved parts and low stiffness parts.

[0023] Secondly, the present invention provides elastic support and guiding constraints for the clamping platform through the first and second leaf springs, so that the clamping platform forms a vibration damping support system with designable stiffness and natural frequency; by adjusting the effective connection position of the first and second leaf springs, the natural frequency of the tooling can be changed, thereby adapting to the dominant vibration modes of different parts.

[0024] Third, the present invention uses an attached fluid viscous damper as an energy dissipation element. This attached fluid viscous damper does not require the traditional two-end connected damper structure. It can provide fluid viscous energy dissipation capability while maintaining a compact structure, which is beneficial to improving the adaptability of the fluid viscous damping vibration reduction fixture at the clamping end of the part in a narrow space.

[0025] Fourth, by employing a combination of a clamping platform, a first leaf spring, a second leaf spring, and an attached fluid viscosity damper, the present invention enables the clamping end of the workpiece to have elastic tuning and damping energy dissipation functions, thereby reducing the frequency response peak during the machining process and improving machining stability and critical cutting depth. Attached Figure Description

[0026] It should be noted that the specific embodiments described below in conjunction with the accompanying drawings are only used to clearly and completely illustrate the technical solution of the present invention, and should not be construed as limiting the scope of protection of the present invention. Unless otherwise expressly stated, the technical and scientific terms used herein should have the meanings commonly understood by those skilled in the art; the specific names used in the text for ease of description are only used to distinguish and describe the corresponding structures, components and their connection relationships, and do not constitute a limitation on their structural form, material, quantity, size or arrangement.

[0027] The terms "first," "second," "upper," "lower," "inner," and "outer" used herein are only for distinguishing related components or describing the relative positional relationship of components in the states shown in the accompanying drawings, and do not indicate that the related components must have a specific order, quantity, or installation direction. For multiple holes, slots, or other structures with the same function arranged side by side on the same part, the same reference numerals may be used to indicate them uniformly in the accompanying drawings. The accompanying drawings are for illustrative purposes only, and the shape, size, and proportion of each component should not be construed as limiting the invention.

[0028] Figure 1 This is a schematic diagram of the overall structure of the fluid viscosity damping and vibration reduction tooling at the clamping end of the part of the present invention. Figure 2 This is an exploded structural diagram of the fluid viscosity damping and vibration reduction tooling at the clamping end of the part of the present invention. Figure 3 This is a schematic diagram of the structure of the first base and the second base in this invention; Figure 4 This is a schematic diagram of the structure of the fixed platform and the movable platform in this invention; Figure 5 This is a schematic diagram of the structure of the first and second leaf springs in this invention; Figure 6 This is a schematic diagram of the structure of the first upper pressing strip, the first lower pressing strip, the second upper pressing strip, and the second lower pressing strip in this invention; Figure 7 This is a schematic diagram of the exploded structure of the attached fluid viscosity damper in this invention.

[0029] The attached figures are labeled as follows: 100. Part clamping end fluid viscosity damping vibration reduction fixture; 10. Base assembly; 11. First base; 111. First leaf spring mounting surface; 112. First clamping part; 1111. First base connecting hole; 1112. First leaf spring fixing hole; 12. Second base; 121. Second leaf spring mounting surface; 122. Second clamping part; 1211. Second base connecting hole; 1212. Second leaf spring fixing hole; 20. Clamping assembly; 21. Fixed platform; 211. First lower connecting surface; 212. First leaf spring connecting surface; 213. Damper mounting surface; 214. First clamping connecting surface; 215. Second clamping connecting surface; 216. Second leaf spring connecting surface; 217. Second lower connecting surface; 2121. First leaf spring connecting hole; 2131. Damper mounting hole; 2141. First platform connecting hole; 2151. Second platform connecting hole; 2161. Second leaf spring connecting hole; 22. Movable platform; 221. First connecting arm; 222. Second connecting arm; 2211. First adjusting groove; 2221. Second adjusting groove; 31. First leaf spring; 311. End of first leaf spring; 312. First leaf spring plate surface; 3111. First waist-shaped adjustment hole; 3112. First fixing hole; 32. Second leaf spring; 321. Second leaf spring plate surface; 322. Second leaf spring end; 3211. Second waist-shaped adjustment hole; 3212. Second fixing hole; 41. First upper clamping bar; 411. First clamping surface; 412. First upper limit part; 413. First lower limit part; 4111. First fastening hole; 42. First lower clamping bar; 421. Second clamping surface; 422. Second upper limit part; 423. Second lower limit part; 4211. Second fastening hole; 43. Second upper clamping bar; 431. Third clamping surface; 432. Third upper limit part; 433. Third lower limit part; 4311. Third fastening hole; 44. Second lower clamping bar; 441. Fourth clamping surface; 442. Fourth upper limit part; 443. Fourth lower limit part; 4411. Fourth fastening hole; 50. Attached fluid viscosity damper; 51. Damper housing; 511. Mounting flange; 512. Cylindrical surface inside the damping cavity; 513. End cap mating surface; 5111. Housing mounting hole; 5131. End cap connection hole; 52. Mass block; 521. Outer cylindrical surface of the mass block; 53. End cap; 531. Sealing mating surface; 5311. End cap mounting hole; 54. Liquid damping medium. Detailed Implementation

[0030] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0031] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0032] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0033] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations.

[0034] The fixed platform 21 referred to in this article is a platform that serves as a fixed clamping reference relative to the movable platform 22 during the part clamping process, and does not mean that it is completely immobile relative to the base assembly 10.

[0035] like Figures 1 to 7 As shown, this embodiment provides a fluid viscosity damping and vibration reduction fixture 100 for a part clamping end, which is disposed between the machine tool and the clamping end of the part to be processed. The fluid viscosity damping and vibration reduction fixture 100 for the part clamping end includes a base assembly 10, a clamping assembly 20, a first leaf spring 31, a second leaf spring 32, and an attached fluid viscosity damper 50. The clamping assembly 20 includes a fixed platform 21 and a movable platform 22. The movable platform 22 is tunably connected to the fixed platform 21 and together with the fixed platform 21 forms a clamping space for clamping the part to be processed. The first leaf spring 31 and the second leaf spring 32 are respectively disposed on opposite sides of the fixed platform 21, and one end of the first leaf spring 31 and one end of the second leaf spring 32 are respectively connected to the fixed platform 21. The other end of the first leaf spring 31 and the other end of the second leaf spring 32 are respectively connected to the base assembly 10 to provide elastic support for the fixed platform 21 and guide the fixed platform 21 to move relative to the base assembly 10. The attached fluid viscosity damper 50 includes a damper housing 51 fixed to the side of the fixed platform 21, a mass block 52 movably housed in the damper housing 51, and a liquid damping medium 54 filled in the damper housing 51. An annular damping gap is formed between the outer cylindrical surface of the mass block 52 and the inner cylindrical surface of the damping cavity of the damper housing 51. When the fixed platform 21 vibrates, the mass block 52 and the damper housing 51 move relative to each other, causing the liquid damping medium 54 to flow through the annular damping gap and dissipate vibration energy.

[0036] The part clamping end fluid viscosity damping vibration reduction fixture 100 of this invention, by setting an attached fluid viscosity damper 50, can dissipate vibration energy and reduce the probability of vibration or chatter of the part to be processed during the cutting process.

[0037] Here, the fluid viscosity damping and vibration reduction fixture 100 at the clamping end of the part is set between the machine tool and the clamping end of the part to be processed. The attached fluid viscosity damper 50 is mounted on the side of the fixed platform 21, which does not encroach on the cutting area of ​​the part. There is no need to attach damping blocks to the surface of the workpiece, and there is no additional clamping load, thereby avoiding deformation of thin-walled parts and curved parts during processing. It is suitable for milling scenarios of blades and small precision thin-walled parts.

[0038] Optionally, such as Figure 1 and Figure 2 As shown, the first base 11 and the second base 12 are arranged opposite to each other. The first base 11 is provided with a first clamping part 112, and the second base 12 is provided with a second clamping part 122. The first clamping part 112 and the second clamping part 122 are used to clamp and fix the platform 21. Specifically, the first clamping part 112 and the second clamping part 122 are respectively clamped on both sides of the lower part of the fixed platform 21. The double clamping parts encircle and clamp, which improves the support rigidity of the bottom of the fixed platform 21 and reduces the vibration of the base assembly 10 itself.

[0039] Optionally, such as Figure 3 As shown, the first base 11 has a first leaf spring mounting surface 111, a first base connecting hole 1111, and a first leaf spring fixing hole 1112. The second base 12 has a second leaf spring mounting surface 121, a second base connecting hole 1211, and a second leaf spring fixing hole 1212. The number of first base connecting holes 1111 and second base connecting holes 1211 is multiple, such as three or four. The number of first leaf spring fixing holes 1112 can also be multiple. Figure 3 In the first leaf spring fixing hole 1112, there are three holes, and correspondingly, the second leaf spring fixing hole 1212 can also be three holes.

[0040] It should be noted that the first leaf spring fixing hole 1112 and the second leaf spring fixing hole 1212 can both be blind holes to reduce the impact on the fixing platform 21.

[0041] Specifically, such as Figure 3 As shown, the lower part of the fixed platform 21 is provided with a first lower connecting surface 211 and a second lower connecting surface 217 that are arranged opposite to each other. The first lower connecting surface 211 and the second lower connecting surface 217 are respectively arranged toward the first clamping part 112 and the second clamping part 122. The first clamping part 112 is in contact with the first lower connecting surface 211, and the second clamping part 122 is in contact with the second lower connecting surface 217.

[0042] Fasteners are connected to the first base 11 through the first base connection hole 1111 and to the second base 12 through the second base connection hole 1211, so that the first clamping part 112 and the second clamping part 122 clamp the lower part of the fixed platform 21 facing each other. The base assembly 10 can be clamped by a machine tool vise or mounted on a machine tool worktable or other machine tool fixtures.

[0043] like Figure 3 As shown, a portion of the fixed platform 21 is positioned above the first base 11 and the second base 12, and the movable platform 22 is adjustablely mounted on the fixed platform 21. The fixed platform 21 has a first clamping connecting surface 214 and a second clamping connecting surface 215, and the movable platform 22 has a first connecting arm 221 and a second connecting arm 222. The first connecting arm 221 has a first adjusting groove 2211, and the second connecting arm 222 has a second adjusting groove 2221.

[0044] During assembly, fasteners pass through the first adjustment slot 2211 and the second adjustment slot 2221 respectively, and connect to the first platform connection hole 2141 and the second platform connection hole 2151. When the fasteners are not fully locked, the movable platform 22 can move relative to the fixed platform 21 to adjust the clamping space between the movable platform 22 and the fixed platform 21. After the clamping end of the workpiece to be processed is placed into the clamping space, the corresponding fasteners are locked, so that the movable platform 22 and the fixed platform 21 jointly clamp the workpiece to be processed. The first adjustment slot 2211 and the second adjustment slot 2221 adopt an open long slot structure, which facilitates the quick assembly and disassembly of the movable platform 22 and can also adapt to workpieces of different sizes within a certain size range.

[0045] Optionally, the first leaf spring 31 and the second leaf spring 32 are arranged parallel to each other and symmetrically with respect to the fixed platform 21. The upper part of the first leaf spring 31 is connected to the first leaf spring connecting surface 212 of the fixed platform 21 via the first upper clamping strip 41. Its first fixing hole 3112, first fastening hole 4111 and first leaf spring connecting hole 2121 are correspondingly arranged and connected by fasteners. The lower part of the first leaf spring 31 is connected to the first leaf spring mounting surface 111 of the first base 11 via the first lower clamping strip 42. The fastener passes through the second fastening hole 4211 and the first waist-shaped adjustment hole 3111 and then connects to the first leaf spring fixing hole 1112.

[0046] The upper part of the second leaf spring 32 is connected to the second leaf spring connecting surface 216 of the fixed platform 21 via the second upper clamping strip 43. The second fixing hole 3212, the third fastening hole 4311, and the second leaf spring connecting hole 2161 of the second leaf spring 32 are correspondingly provided. The lower part of the second leaf spring 32 is connected to the second leaf spring mounting surface 121 of the second base 12 via the second lower clamping strip 44. The fastener passes through the fourth fastening hole 4411 and the second waist-shaped adjustment hole 3211 and then connects to the second leaf spring fixing hole 1212.

[0047] Alternatively, the first leaf spring 31 and the second leaf spring 32 can also be arranged substantially parallel. In this case, if the first leaf spring 31 and the second leaf spring 32 are parallel to each other, the included angle between them is 0 degrees. The included angle between the first leaf spring 31 and the second leaf spring 32 can also be a small acute angle, such as 2 degrees or 3 degrees. Here, the first leaf spring 31 and the second leaf spring 32 are respectively connected to the base assembly 10 and the fixed platform 21, thereby providing elastic support for the fixed platform 21. The symmetrical arrangement of the first leaf spring 31 and the second leaf spring 32 can make the fixed platform 21 mainly produce slight translational movements along the flexible direction of the first leaf spring 31 and the second leaf spring 32, and suppress the deflection and torsion of the fixed platform 21, making the vibration direction of the clamping end more stable.

[0048] The first upper clamping bar 41 and the first lower clamping bar 42 clamp the first leaf spring 31 through the first clamping surface 411 and the second clamping surface 421, respectively; the second upper clamping bar 43 and the second lower clamping bar 44 clamp the second leaf spring 32 through the third clamping surface 431 and the fourth clamping surface 441, respectively. The first upper clamping bar 41 and the first lower clamping bar 42 extend along the width direction of the first leaf spring 31, so that the preload generated by the fastener is evenly transmitted to the first leaf spring 31, reducing the local stress concentration of the first leaf spring 31 near the first waist-shaped adjustment hole 3111 and the first fixing hole 3112.

[0049] Similarly, the second upper clamping bar 43 and the second lower clamping bar 44 both extend along the width direction of the second leaf spring 32, so that the preload generated by the fastener is evenly transmitted to the second leaf spring 32, reducing the local stress concentration of the second leaf spring 32 near the second waist-shaped adjustment hole 3211 and the second fixing hole 3212.

[0050] like Figure 6 As shown, the first upper clamping bar 41 is provided with a first upper limit portion 412 and a first lower limit portion 413, which are spaced apart in the vertical direction. The first lower clamping bar 42 is provided with a second upper limit portion 422 and a second lower limit portion 423, which are spaced apart in the vertical direction. The second upper clamping bar 43 is provided with a third upper limit portion 432 and a third lower limit portion 433, which are spaced apart in the vertical direction. The second lower clamping bar 44 is provided with a fourth upper limit portion 442 and a fourth lower limit portion 443, which are spaced apart in the vertical direction.

[0051] The first upper limit portion 412 and the first lower limit portion 413 are used to limit the relative positions of the first upper pressing bar 41 and the first leaf spring 31, respectively, and reduce the possibility of the first upper pressing bar 41 slipping during vibration. Similarly, the second upper limit portion 422 and the second lower limit portion 423 are used to limit the relative positions of the first lower pressing bar 42 and the first leaf spring 31, respectively, and reduce the possibility of the first lower pressing bar 42 slipping during vibration. Similarly, the third upper limit portion 432 and the third lower limit portion 433 are used to limit the relative positions of the second upper pressing bar 43 and the second leaf spring 32, respectively, and reduce the possibility of the second upper pressing bar 43 slipping during vibration. Likewise, the fourth upper limit portion 442 and the fourth lower limit portion 443 are used to limit the relative positions of the second lower pressing bar 44 and the second leaf spring 32, respectively, and reduce the possibility of the second lower pressing bar 44 slipping during vibration.

[0052] It is important to emphasize that the first upper clamping bar 41 can cover the entire width of the first leaf spring 31, and the first lower clamping bar 42 can cover the entire width of the first leaf spring 31. The first upper clamping bar 41 and the first lower clamping bar 42 each have their own limiting structure, which restricts the relative sliding between the first leaf spring 31 and the fixed platform 21 and the base assembly 10 during vibration, ensuring that the effective length and equivalent stiffness of the first leaf spring 31 are stable in the long term, and the vibration reduction effect will not decrease with the processing time.

[0053] The second upper clamping bar 43 can cover the entire width of the second leaf spring 32, and the second lower clamping bar 44 can cover the entire width of the second leaf spring 32. The second upper clamping bar 43 and the second lower clamping bar 44 each have their own limiting structure, which restricts the relative sliding between the second leaf spring 32 and the fixed platform 21 and the base assembly 10 during vibration, ensuring that the effective length and equivalent stiffness of the second leaf spring 32 are stable in the long term, and the vibration reduction effect will not decrease with the processing time.

[0054] It should be noted that, as Figure 5 As shown, the second leaf spring 32 has a rectangular plate structure. The four sides of the second leaf spring 32 are called the second leaf spring ends 322. The surface of the second leaf spring 32 facing the second base 12 and the surface facing away from the second base 12 are both second leaf spring surfaces 321. The second leaf spring surfaces 321 facing the second base 12 can be fitted into the second base 12. Similarly, the first leaf spring 31 also has a rectangular plate structure. The four sides of the first leaf spring 31 are called the first leaf spring ends 311. The surface of the first leaf spring 31 facing the first base 11 and the surface facing away from the first base 11 are both first leaf spring surfaces 312. The first leaf spring surfaces 311 facing the first base 11 can be fitted into the first base 11.

[0055] Continue to refer to Figure 5As shown, the first leaf spring 31 is provided with a plurality of first waist-shaped adjustment holes 3111, which are spaced apart along the width direction of the first leaf spring 31. The second leaf spring 32 is provided with a plurality of second waist-shaped adjustment holes 3211, which are spaced apart along the width direction of the second leaf spring 32. After loosening the fastener at the first lower clamping bar 42, the fixed position of the first leaf spring 31 and the base assembly 10 can be adjusted along the length direction of the first waist-shaped adjustment holes 3111, thereby changing the effective deformation length of the first leaf spring 31. Similarly, after loosening the fastener at the second lower clamping bar 44, the fixed position of the second leaf spring 32 and the base assembly 10 can be adjusted along the length direction of the second waist-shaped adjustment holes 3211, thereby changing the effective deformation length of the second leaf spring 32.

[0056] Specifically, the first waist-shaped adjustment hole 3111 extends along the length of the first leaf spring 31, and the second waist-shaped adjustment hole 3211 extends along the length of the second leaf spring 32. After adjusting the connection positions of the first leaf spring 31 and the base assembly 10 and the second leaf spring 32 and the base assembly 10, the fasteners are tightened again, which can change the equivalent stiffness and natural frequency of the fluid viscosity damping damping fixture 100 at the clamping end of the vibration damping part, so that it matches the dominant vibration frequency of the part to be processed.

[0057] like Figure 2 As shown, the outer cylindrical surface 521 of the mass block 52 is spaced apart from the inner cylindrical surface 512 of the damping cavity, forming an annular damping gap between them for the flow of the liquid damping medium 54. The liquid damping medium 54 fills the damping cavity and can be dimethyl silicone oil, other silicone oils, or liquid media with suitable viscosity and temperature stability.

[0058] Optionally, such as Figure 7 As shown, the damper housing 51 is provided with a mounting flange 511, which is fixed to the damper mounting surface 213 of the fixed platform 21 by fasteners, as follows. Figure 4 As shown, the damper mounting surface 213 enables the installation of the attached fluid viscous damper 50; the open end of the damper housing 51 is provided with an end cap 53 that is sealed to the damper housing 51.

[0059] Specifically, the mounting flange 511 is provided with housing mounting holes 5111. There are multiple housing mounting holes 5111, which can be detachably connected to the damper mounting surface 213 of the fixed platform 21 through the housing mounting holes 5111 using fasteners.

[0060] The end cap 53 has a sealing mating surface 531, which mates with the end cap mating surface 513 of the damper housing 51. Fasteners pass through the end cap mounting hole 5311 and connect to the end cap connection hole 5131 of the damper housing 51 to fix the end cap 53 to the damper housing 51 and seal the damping cavity. A sealing ring, gasket, or sealant can be provided between the end cap 53 and the damper housing 51 to prevent leakage of the liquid damping medium 54.

[0061] When the damper housing 51 vibrates with the fixed platform 21, the mass block 52 moves relative to the damper housing 51 under the action of inertia. The liquid damping medium 54 flows through the annular damping gap under pressure and generates pressure difference resistance and viscous shear resistance during the flow process, thereby converting part of the vibration mechanical energy into heat energy and dissipating it.

[0062] Optionally, in order to connect the attached fluid viscous damper 50 to the fixed platform 21, a damper mounting hole 2131 can be provided on the fixed platform 21 to facilitate the connection of the attached fluid viscous damper 50 and the fixed platform 21 using fasteners.

[0063] The liquid damping medium 54 is dimethyl silicone oil or other silicone oil with a predetermined viscosity. The mass block 52 is made of tungsten alloy. Tungsten alloy has a high density and good corrosion resistance, and its mass is much greater than that of steel or copper for the same volume. This allows it to obtain sufficient inertial mass within a limited installation space, reducing the overall size of the damper. The damper housing 51 is made of aluminum alloy, which can dissipate the heat generated by damping motion in a timely manner, suppress the temperature rise of the silicone oil, and prevent viscosity drift caused by high temperature.

[0064] The embodiments of the present invention combine a silicone oil damping medium, a tungsten alloy mass block, and an aluminum alloy shell to achieve large inertial mass and stable viscous damping in a compact structure; the shell is lightweight while also taking into account heat dissipation and suppressing temperature drift of the damping medium; the chemical compatibility between the materials is good, and corrosion and medium failure are not likely to occur during long-term operation, resulting in long-term stable vibration reduction performance, small structure size, and high reliability.

[0065] Optionally, the attached fluid viscosity damper 50 is located below the machining end of the workpiece to avoid the machining path of the cutting tool, thereby reducing the impact on the machining process.

[0066] Embodiments of the present invention also provide an amplitude optimization design method for a fluid viscosity damping vibration reduction fixture at the clamping end of a part, comprising: Obtain the equivalent mass of the part to be processed. Equivalent stiffness and frequency response function; The fluid viscosity damping and vibration reduction fixture 100 at the part clamping end is equivalent to having an equivalent mass. Equivalent stiffness and equivalent damping A single-degree-of-freedom system; A two-degree-of-freedom coupled system is established, consisting of the part to be processed and the fluid viscous damping vibration reduction fixture 100 at the clamping end of the part. The optimization objective is to minimize the maximum amplitude of the frequency response function of the part to be processed within the target frequency range.

[0067] in, Let Ω be the frequency response function of the part to be processed, and Ω be the target frequency range. Variables within the target frequency range; Based on the optimized equivalent stiffness and equivalent damping The structural parameters of the first leaf spring 31, the second leaf spring 32, and the attached fluid viscosity damper 50 are determined.

[0068] Furthermore, make the quality ratio stiffness ratio The optimal stiffness ratio is determined as follows: :

[0069] : Take the unique positive real root of the equation, where, This represents the optimal stiffness ratio.

[0070] Furthermore, after determining the optimal stiffness ratio, the square of the dimensionless frequency is denoted as... The square of the damping ratio is denoted as Based on the two fixed points of a two-degree-of-freedom coupled system Determine the square value of the damping ratio respectively : in, ;in, and It is an equation The two roots; The optimal damping ratio is determined according to the following formula:

[0071] The optimal equivalent damping is determined by the following formula:

[0072] Adjust the effective deformation length of the first and second leaf springs according to the optimal stiffness ratio, and determine the viscosity of the liquid damping medium and / or the size of the annular damping gap according to the optimal equivalent damping.

[0073] Under the approximate condition of neglecting the inherent damping of the workpiece, when the damping ratio of the fluid viscous damping vibration reduction fixture 100 at the clamping end of the workpiece is changed, the system amplitude-frequency curve has two fixed points that are basically independent of the damping ratio. First, two fixed points are determined using fixed-point theory. Then, the optimal stiffness ratio is determined by balancing the low-frequency static response and the dynamic response at the fixed points. When the mass ratio... When, make the fixed point The amplitudes at each point are equal, thus obtaining the optimal stiffness ratio. When the mass ratio At that time, the influence of the low-frequency static response on the maximum amplitude is not negligible, so let the first fixed point... The amplitude at the zero frequency is equal to the amplitude at the zero frequency, thus obtaining a cubic equation for the optimal stiffness ratio, and taking the unique positive real root of the equation as the optimal stiffness ratio.

[0074] After determining the optimal stiffness ratio, let Let the amplitude of the frequency response function be at the fixed point respectively. to The derivative is zero, thus yielding the square value of the corresponding damping ratio. .when When two fixed points jointly control the system to achieve maximum response, the following method is adopted: The arithmetic mean of the values ​​determines the optimal damping ratio; when At that time, zero frequency point and first fixed point Joint control of maximum response, using Determine the optimal damping ratio. Then, calculate the optimal equivalent damping based on the optimal damping ratio. .

[0075] Finally, the equivalent stiffness corresponding to the optimal stiffness ratio is converted into the effective deformation length of the first leaf spring 31 and the second leaf spring 32, and the optimal equivalent damping is converted into structural parameters such as the viscosity of the liquid damping medium, the size of the annular damping gap, and the size of the mass block, thereby completing the design of the dynamic parameters to the actual structural parameters of the fluid viscosity damping vibration reduction fixture 100 at the clamping end of the part.

[0076] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Without departing from the concept of the present invention, those skilled in the art can make adjustments, substitutions, or combinations to the above structural forms, connection methods, material selections, and parameter configurations. All equivalent substitutions, simple transformations, and improvements made based on the technical concept of the present invention should fall within the protection scope of the present invention; the protection scope of the present invention is defined by the scope of the claims.

Claims

1. A fluid viscosity damping vibration reduction fixture for clamping a part, used to be disposed between the clamping end of a machine tool and the part to be processed, characterized in that, include: Base assembly; The clamping assembly includes a fixed platform and a movable platform, wherein the movable platform is tunably connected to the fixed platform and together with the fixed platform forms a clamping space for clamping the part to be processed; A first leaf spring and a second leaf spring are respectively disposed on opposite sides of the fixed platform. One end of the first leaf spring and one end of the second leaf spring are respectively connected to the fixed platform, and the other end of the first leaf spring and the other end of the second leaf spring are respectively connected to the base assembly, so as to provide elastic support for the fixed platform and guide the fixed platform to move relative to the base assembly. as well as An attached fluid viscosity damper includes a damper housing fixed to the side of the fixed platform, a mass block movably housed within the damper housing, and a liquid damping medium filled within the damper housing; an annular damping gap is formed between the outer cylindrical surface of the mass block and the inner cylindrical surface of the damping cavity of the damper housing. When the fixed platform vibrates, the mass block and the damper housing move relative to each other, causing the liquid damping medium to flow through the annular damping gap and dissipate vibration energy.

2. The part clamping end fluid viscosity damping vibration reduction fixture according to claim 1, characterized in that, The base assembly includes a first base and a second base disposed opposite to each other; the first base is provided with a first clamping part, and the second base is provided with a second clamping part, the first clamping part and the second clamping part being used to clamp the fixed platform.

3. The part clamping end fluid viscosity damping vibration reduction fixture according to claim 1, characterized in that, The active platform includes a first connecting arm and a second connecting arm. The first connecting arm and the second connecting arm are respectively provided with a first adjustment groove and a second adjustment groove. The first adjustment groove and the second adjustment groove are respectively provided with an opening. Fasteners pass through the first adjustment slot and the second adjustment slot respectively and are connected to the fixed platform to adjust the position of the movable platform relative to the fixed platform.

4. The part clamping end fluid viscosity damping vibration reduction fixture according to claim 1, characterized in that, The first leaf spring and the second leaf spring are arranged parallel to each other and symmetrically with respect to the fixed platform, so as to guide the fixed platform to move along the flexible direction of the first leaf spring and the second leaf spring.

5. The part clamping end fluid viscosity damping vibration reduction fixture according to claim 1, characterized in that, The first leaf spring and the second leaf spring are respectively provided with waist-shaped adjustment holes extending along their own length direction; a fastener passes through the waist-shaped adjustment hole of the first leaf spring to connect the first leaf spring to the base assembly, and a fastener passes through the waist-shaped adjustment hole of the second leaf spring to connect the second leaf spring to the base assembly.

6. The part clamping end fluid viscosity damping vibration reduction fixture according to claim 5, characterized in that, The first leaf spring is fixed to the fixed platform by a first upper clamping strip, and the first leaf spring is fixed to the base assembly by a first lower clamping strip; and / or, the second leaf spring is fixed to the fixed platform by a second upper clamping strip, and the second leaf spring is fixed to the base assembly by a second lower clamping strip.

7. The part clamping end fluid viscosity damping vibration reduction fixture according to any one of claims 1 to 6, characterized in that, The damper housing is provided with a mounting flange, which is fixed to the damper mounting surface of the fixed platform by fasteners; the open end of the damper housing is provided with an end cap that is sealed to the damper housing.

8. A method for amplitude optimization design of a part clamping end fluid viscous damping vibration reduction fixture as described in any one of claims 1 to 7, used for amplitude optimization of the part clamping end fluid viscous damping vibration reduction fixture, characterized in that, include: Obtain the equivalent mass of the part to be processed. Equivalent stiffness and frequency response function; The fluid viscosity damping and vibration reduction fixture at the clamping end of the part is equivalent to having an equivalent mass. Equivalent stiffness and equivalent damping A single-degree-of-freedom system; A two-degree-of-freedom coupled system is established, consisting of the part to be processed and the fluid viscous damping vibration reduction fixture at the clamping end of the part. The optimization objective is to minimize the maximum amplitude of the frequency response function of the part to be processed within the target frequency range. in, Let Ω be the frequency response function of the part to be processed, and Ω be the target frequency range. Variables within the target frequency range; Based on the optimized equivalent stiffness and equivalent damping The structural parameters of the first leaf spring, the second leaf spring, and the attached fluid viscosity damper are determined.

9. The amplitude optimization design method according to claim 8, characterized in that, Let the mass ratio stiffness ratio The optimal stiffness ratio is determined as follows: : : Take the unique positive real root of the equation, where, This represents the optimal stiffness ratio.

10. The amplitude optimization design method according to claim 9, characterized in that, After determining the optimal stiffness ratio, the square of the dimensionless frequency is denoted as... The square of the damping ratio is denoted as Based on the two fixed points of the two-degree-of-freedom coupled system Determine the square value of the damping ratio respectively : in, ;in, and It is an equation The two roots; The optimal damping ratio is determined according to the following formula: The optimal equivalent damping is determined by the following formula: The effective deformation lengths of the first and second leaf springs are adjusted according to the optimal stiffness ratio, and the viscosity of the liquid damping medium and / or the size of the annular damping gap are determined according to the optimal equivalent damping.

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