A Removable Fast Tool Servo Platform with Bidirectionally Adjustable Stiffness and Method

Abstract

The present invention discloses a detachable fast tool servo platform with bidirectional stiffness adjustment and a method thereof, belonging to the technical field of fast tool servo platforms. It includes a frame which has a central cavity. A tool head is arranged in the middle of the frame. The tool head is connected to a first S-shaped flexible hinge guide plate. The first S-shaped flexible hinge guide plate and the second S-shaped flexible hinge guide plate are arranged oppositely. The first S-shaped flexible hinge guide plate and the second S-shaped flexible hinge guide plate are connected by a connecting block, and the connecting block is connected to a power device through a thrust block. This fast tool servo platform drives the tool head through the S-shaped flexible hinge guide plate to achieve a super-large stroke of millimeters and a motion accuracy of micro-nanometers, and realizes the bidirectional adjustment and locking of the platform stiffness by adopting a double-lead adjusting stud.

Description

Technical Field

[0001] The present invention belongs to the technical field of fast tool servo platforms, and particularly relates to a detachable fast tool servo platform with bidirectionally adjustable stiffness and a method therefor. Background Art

[0002] The statements herein only provide the background art related to the present invention and do not necessarily constitute the prior art.

[0003] With the increasing progress of science and technology, ultra-precision machining technology has also developed rapidly. Microstructure components with complex surface profiles are widely used in many fields such as military, aerospace, high-tech equipment, and optical fiber communication. Such components have complex structures and high machining accuracy requirements, and it is difficult to meet the actual machining needs using traditional machining methods. With the continuous progress of technology, many ultra-precision machining methods have emerged to meet the machining requirements of microstructured surfaces, such as photolithography machining, micro-grinding machining, laser machining, fast tool servo, etc. Although the above methods have their own advantages and disadvantages, the fast tool servo technology, as a relatively classic ultra-precision machining technology, is one of the research hotspots for turning machining of microstructure components.

[0004] Fast tool servo machining refers to a process in ultra-high-precision turning machining where, with the aid of a micro-feed mechanism of a fast tool servo installed axially, the tool is driven to perform a high-frequency, small-amplitude reciprocating feed motion and cooperate with a high-precision radial feed to jointly complete the turning machining process of complex curved surfaces. Compared with the feed frequency of dozens of hertz in general, the axial feed frequency of the fast tool servo micro-feed mechanism can mostly reach several thousand hertz or even higher, thus greatly improving the machining efficiency. Compared with other ultra-precision machining methods, the fast tool servo turning machining technology has the characteristics of high frequency response and high efficiency, and a complex microstructured surface with extremely high surface accuracy can be obtained in one machining, which is suitable for the high-quality and efficient machining of microstructure components such as optical elements.

[0005] Fast tool servo turning machining requires high-frequency response and high-precision micro-feeding. Currently, the driving methods of micro-feed mechanisms mainly include piezoelectric ceramics and voice coil motors. The fast tool servo driven by piezoelectric ceramics has many advantages such as fast response speed, high acceleration, wide frequency response range, and easy control, while the fast tool servo driven by a voice coil motor mostly has an extremely long working stroke.

[0006] The fast tool servo micro-feed platform is a very important component in the fast tool servo machining system. As a high-speed and high-precision displacement output mechanism, the quality of its performance has a direct impact on the surface quality of the micro-structures machined by the fast tool servo. At present, most existing fast tool servo platforms use integrated compliant mechanisms to achieve micro-nano level precision guiding motion, and they are mostly servo platforms with fixed stiffness and dynamic characteristics. Even when later there appeared fast tool servo platforms with adjustable stiffness, due to the one-way adjustment form they adopted, the stiffness adjustment range was limited. In addition, although the integrated compliant mechanism has advantages such as no friction, no wear, and no need for assembly, it cannot achieve the detachable and replaceable of the compliant mechanism of the fast tool servo platform, which in turn leads to disadvantages such as limited usage range and poor maintainability. Summary of the Invention

[0007] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a detachable fast tool servo platform and method with bidirectional adjustable stiffness. This fast tool servo platform drives the tool head through an S-shaped flexible hinge guide plate to achieve a super-large stroke of millimeters and a motion accuracy of micro-nano levels, and by adopting a double-lead adjusting stud, it realizes the bidirectional adjustment and locking of the platform stiffness.

[0008] To achieve the above purpose, the present invention is realized through the following technical solutions:

[0009] In the first aspect, the present invention provides a detachable fast tool servo platform with bidirectional adjustable stiffness, including a frame. The frame has a central cavity, and a tool head is arranged in the middle of the frame. The tool head is connected to a first S-shaped flexible hinge guide plate. The first S-shaped flexible hinge guide plate is arranged opposite to the second S-shaped flexible hinge guide plate. The first S-shaped flexible hinge guide plate and the second S-shaped flexible hinge guide plate are connected by a connecting block, and the connecting block is connected to a power device through a thrust block.

[0010] As a further technical solution, the end of the first S-shaped flexible hinge guide plate is connected to the frame, the end of the second S-shaped flexible hinge guide plate is connected to the frame, and the stiffness of the first S-shaped flexible hinge guide plate and the second S-shaped flexible hinge guide plate is adjustable.

[0011] As a further technical solution, the frame is fixedly provided with a fixed block, and the fixed block is provided with a threaded hole for the double-lead adjusting stud to pass through. One end of the double-lead adjusting stud is threadedly connected to the fixed block, and the other end of the double-lead adjusting stud is threadedly connected to the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate.

[0012] As a further technical solution, a fastening block is sleeved on the end of the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate, and the fastening block is fixedly connected to the frame.

[0013] As a further technical solution, a fastening nut is sleeved on the end of the double-lead adjusting stud, and the fastening nut is in contact with the fixed block.

[0014] As a further technical solution, the first S-shaped flexible hinge guide plate includes a first connecting seat. A plurality of first S-shaped flexible hinges are circumferentially arranged on the outer circumference of the first connecting seat. A first adjusting head is arranged at the end of the first S-shaped flexible hinge, and the first adjusting head is connected to the frame.

[0015] As a further technical solution, the second S-shaped flexible hinge guide plate includes a second connecting seat. A plurality of second S-shaped flexible hinges are circumferentially arranged on the outer circumference of the second connecting seat. A second adjusting head is arranged at the end of the second S-shaped flexible hinge, and the second adjusting head is connected to the frame.

[0016] As a further technical solution, the first S-shaped flexible hinges and the second S-shaped flexible hinges are arranged in a one-to-one correspondence, and the connecting block is connected between the first connecting seat and the second connecting seat.

[0017] In a second aspect, the present invention also provides a working method for a detachable fast tool servo platform with two-way adjustable stiffness as described above, including the following steps:

[0018] After the power device is powered on, it pushes the thrust block, and the thrust block pushes the second S-shaped flexible hinge guide plate, and then pushes the first S-shaped flexible hinge guide plate via the connecting block. The two S-shaped flexible hinge guide plates undergo micro-deformation, and then drive the tool head to achieve a super-large stroke of millimeters and a motion accuracy of micro-nanometers.

[0019] As a further technical solution, during the working process, by rotating the double-lead adjusting stud, due to the different thread leads or pitches of its cooperation with the fixed block, the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate, through the axial feed difference generated when the double-lead adjusting stud rotates one week, generates a pulling force and a pushing force on the S-shaped flexible hinge guide plate, and realizes the stiffness adjustment of the flexible hinge guide plate.

[0020] The beneficial effects of the present invention are as follows:

[0021] For the fast tool servo platform of the present invention, after the power device is powered on, it can push the thrust block, and the thrust block pushes the second S-shaped flexible hinge guide plate, and then pushes the first S-shaped flexible hinge guide plate via the connecting block. The two S-shaped flexible hinge guide plates undergo micro-deformation, and then drive the tool head to achieve a super-large stroke of millimeters and a motion accuracy of micro-nanometers.

[0022] For the fast tool servo platform of the present invention, the platform feed guiding mechanism is composed of S-shaped flexible hinge guide plates, which not only has the high stiffness of the previous flexible hinge platform and the large stroke of the flexible plate spring platform, but also is more suitable for the large-range adjustment of the platform stiffness.

[0023] The quick tool servo platform of the present invention adopts a double-lead adjusting stud, and the thread lead / pitch at the connection between the double-lead adjusting stud and the fixed block, the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate is different. By the axial feed difference generated when the double-lead adjusting stud rotates one week, the tensile force and thrust force on the S-shaped flexible hinge guide plate are generated, and then the stiffness adjustment of the flexible hinge guide mechanism is realized; it realizes the two-way adjustment, guiding and fastening restraint of the stiffness of the quick tool servo platform. The double-lead fastening and guiding mechanism can not only adjust the platform stiffness, increase the applicable range, but also reduce the load stress of the double-lead stud, and improve the reliability and service life of the adjustment mechanism.

[0024] The quick tool servo platform of the present invention adopts a double-lead adjusting stud and an S-shaped flexible hinge guide mechanism, which can not only realize the adjustment of the platform stiffness, but also the working stroke can increase as the stiffness decreases, realizing the on-demand adjustment of the platform dynamic characteristics (related to stiffness) and the working stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0026] Figure 1 is an axonometric schematic view of the quick tool servo platform according to one or more embodiments of the present invention;

[0027] Figure 2 is a front view schematic view of the quick tool servo platform according to one or more embodiments of the present invention;

[0028] Figure 3 is a side view schematic view of the quick tool servo platform according to one or more embodiments of the present invention;

[0029] Figure 4 is a schematic view of the double-lead adjusting stud according to one or more embodiments of the present invention;

[0030] Figure 5 is a schematic view of the first S-shaped flexible hinge guide plate according to one or more embodiments of the present invention;

[0031] In the figure: the distances or dimensions between each part are exaggerated for showing the positions of each part, and the schematic view is only for illustration;

[0032] Among them, 1 is the frame, 2 is the bottom plate, 3 is the rib plate, 4 is the power device support plate, 5 is the connecting block, 6 is the power device, 7 is the thrust block, 8 is the second S-shaped flexible hinge guide plate, 9 is the fixed block, 10 is the fastening nut, 11 is the double-lead adjusting stud, 12 is the fastening block, 13 is the first S-shaped flexible hinge guide plate, 14 is the tool head, 15 is the first connecting seat, 16 is the second connecting seat, 17 is the S-shaped flexible hinge, 18 is the adjusting head. Detailed Implementation Manner

[0033] It should be noted that the following detailed description is illustrative and aims to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0034] In a typical implementation manner of the present invention, as Figure 1 shown, a detachable fast tool servo platform with bidirectionally adjustable stiffness is proposed, which includes a frame 1. The frame 1 has a central cavity. A tool head 14 is arranged in the middle of the frame 1. The tool head 14 is connected to a first S-shaped flexible hinge guiding plate 13. The end of the first S-shaped flexible hinge guiding plate 13 is connected to the frame 1. The first S-shaped flexible hinge guiding plate 13 is arranged opposite to a second S-shaped flexible hinge guiding plate 8. The end of the second S-shaped flexible hinge guiding plate 8 is connected to the frame 1. The first S-shaped flexible hinge guiding plate 13 and the second S-shaped flexible hinge guiding plate 8 are connected by a connecting block 5. The connecting block 5 is connected to a thrust block 7 and a power device 6. When the power device is energized, it pushes the thrust block 7. The thrust block 7 pushes the flexible hinge guiding plate, causing the flexible hinge guiding plate to undergo a micro-deformation, driving the tool head 14 to achieve a super-large stroke of millimeters and a motion accuracy of micro-nanometers.

[0035] Specifically, both the first S-shaped flexible hinge guiding plate 13 and the second S-shaped flexible hinge guiding plate 8 are connected to the connecting block 5; the middle of the first S-shaped flexible hinge guiding plate 13 is connected to the connecting block 5, and the end of the first S-shaped flexible hinge guiding plate 13 is connected to the frame 1; the middle of the second S-shaped flexible hinge guiding plate 8 is connected to the connecting block 5, and the end of the second S-shaped flexible hinge guiding plate 8 is connected to the frame 1.

[0036] Both the first S-shaped flexible hinge guiding plate 13 and the second S-shaped flexible hinge guiding plate 8 are integrated wavy plate bodies formed by sequentially connecting a plurality of S-shaped flexible hinges. Specifically, as Figure 5 shown, both the first S-shaped flexible hinge guiding plate 13 and the second S-shaped flexible hinge guiding plate 8 are composed of an S-shaped flexible hinge 17, an intermediate connecting seat, and an adjusting head 18. The S-shaped flexible hinge 17, the intermediate connecting seat, and the adjusting head 18 are of an integral structure; a plurality of S-shaped flexible hinges 17 are radially outwardly extended from the outer circumference of the intermediate connecting seat for both S-shaped flexible hinge guiding plates. An adjusting head 18 is arranged at the end of the S-shaped flexible hinge 17, and the adjusting head is connected to the frame 1. The S-shaped flexible hinge 17 is an S-shaped plate structure. The S-shaped flexible hinges 17 of the two S-shaped flexible hinge guiding plates are arranged opposite to each other one by one.

[0037] In this embodiment, the middle connecting seat of the first S-shaped flexible hinge guide plate 13 is the first connecting seat 15, and the middle connecting seat of the second S-shaped flexible hinge guide plate 8 is the second connecting seat 16. The connecting block 5 is connected between the first connecting seat 15 and the second connecting seat 16 to connect the first S-shaped flexible hinge guide plate 13 and the second S-shaped flexible hinge guide plate 8. The tool head 14 is fixed to the first connecting seat 15, the second connecting seat 16 is fixedly connected to the thrust block 7, the thrust block 7 is fixedly connected to the power device 6, the power device 6 is fixed to the power device support plate 4, the bottom of the power device support plate 4 is fixed to the bottom plate 2, and stiffening ribs 3 are provided on the power device support plate 4 and the bottom plate 2 for reinforcement; the frame 1 is also fixedly connected to the bottom plate 2.

[0038] The frame 1 is fixedly provided with a fixing block 9. The fixing block 9 is provided with a threaded hole for the double-lead adjusting stud 11 to pass through. One end of the double-lead adjusting stud 11 is threadedly engaged with the fixing block 9, and the other end of the double-lead adjusting stud 11 is threadedly engaged with the first S-shaped flexible hinge guide plate 13 / the second S-shaped flexible hinge guide plate 8; both ends of the double-lead adjusting stud 11 are provided with threads of two different leads (or different pitches), and the threads of the two different leads are respectively engaged with the fixing block 9 and the first S-shaped flexible hinge guide plate 13 / the second S-shaped flexible hinge guide plate 8 (that is, the lead / pitch of the threads of the double-lead adjusting stud engaged with the fixing block and the S-shaped flexible hinge guide plate is different). Therefore, by using the axial feed difference generated when the threaded column rotates one week with different leads (or different pitches), the pulling force and thrust on the S-shaped flexible hinge guide plate are generated, and thus the stiffness adjustment of the flexible hinge guide mechanism is realized. By rotating the double-lead adjusting stud 11 forward or backward, the S-shaped flexible hinge is pushed / pulled to elongate or shorten, and thus the two-way adjustment of the stiffness is realized.

[0039] A fastening nut 10 is sleeved on the end of the double-lead adjusting stud 11. The fastening nut 10 is in contact with the fixing block 9 and is used for fastening after the double-lead thread is adjusted to reduce the loosening of the threaded column. The fixing block 9 fixes the double-lead adjusting stud 11 to the frame.

[0040] The fastening block 12 is C-shaped. The fastening block 12 is sleeved on the outer periphery of the end of the first S-shaped flexible hinge guide plate 13 / the second S-shaped flexible hinge guide plate 8, and the fastening block 12 is fixedly connected to the frame 1 by bolts or the like for fastening after the stiffness of the S-shaped flexible hinge guide plate is adjusted; specifically, when setting, the fastening block 12 is sleeved at the adjustment head. By the pressing of the C-shaped fastening block, the adjusting stud is no longer stressed, reducing the variable load stress of the adjusting stud during the movement of the platform, avoiding the fracture of the adjusting stud, and improving the reliability and service life of the adjusting stud.

[0041] In this embodiment, the power device 6 uses a voice coil motor.

[0042] In an alternative embodiment, the frame 1 is a polygonal structure, and the first S-shaped flexible hinge guide plate 13 and the second S-shaped flexible hinge guide plate 8 are connected to the sides of the frame 1. In this embodiment, both the first S-shaped flexible hinge guide plate 13 and the second S-shaped flexible hinge guide plate 8 are provided with 3 S-shaped flexible hinges. The frame 1 is a regular hexagon structure, and the S-shaped flexible hinges of the first S-shaped flexible hinge guide plate 13 and the second S-shaped flexible hinge guide plate 8 are evenly distributed on the outer periphery of the connecting block 5 and fixedly connected to the sides of the frame 1.

[0043] The fast tool servo platform can adjust the platform stiffness bidirectionally through double-lead adjusting studs, increasing the adjustable range of the platform stroke and dynamic characteristics. The S-shaped flexible hinge has the high stiffness of the conventional flexible hinge platform and the large stroke of the flexible plate spring platform, and is more suitable for the large-range adjustment of the platform stiffness. For the fast tool servo platform, the double-lead fastening guide mechanism can not only adjust the platform stiffness and increase the applicable range, but also play the role of unloading the adjusting stud, reducing the load stress of the double-lead stud, and improving the reliability and service life of the adjusting mechanism. The detachable S-shaped flexible hinge guide plate is adopted, which not only has the advantages of frictionless, gapless, non-wearing, and integrated manufacturing, but also can realize the disassembly, replacement, and maintenance of the platform, improving the maintainability and reuse efficiency of the platform and reducing the use cost.

[0044] The fast tool servo platform uses internal double-lead adjusting studs to achieve bidirectional adjustment and locking of the platform stiffness, and at the same time selects the structural layout form of detachable S-shaped flexible hinges, making the fast tool servo platform have the advantages of wide applicable range, large working stroke, and high maintainability, and solving the problems of non-adjustable or small adjustable range of the platform stiffness, small working stroke, and poor maintainability of the traditional fast tool servo platform.

[0045] The working principle of the detachable fast tool servo platform with bidirectionally adjustable stiffness is as follows:

[0046] After the power device 6 is energized, it pushes the thrust block 7, and the thrust block 7 pushes the second S-shaped flexible hinge guide plate 8, and then pushes the first S-shaped flexible hinge guide plate 13 via the connecting block 5. The two S-shaped flexible hinge guide plates undergo micro-deformation, and then drive the tool head 14 to achieve a super-large stroke of millimeters and a motion accuracy of micro-nanometers.

[0047] During the working process, by rotating the double-lead adjusting stud 11, due to the different thread leads or pitches of its cooperation with the fixed block 9 and the first S-shaped flexible hinge guide plate 13 / the second S-shaped flexible hinge guide plate 8, the axial feed difference generated when the double-lead adjusting stud rotates one week can be used to generate the pulling force and pushing force on the S-shaped flexible hinge guide plate, thereby realizing the stiffness adjustment of the flexible hinge guide mechanism.

[0048] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A detachable fast tool servo platform with bidirectionally adjustable stiffness, characterized in that It includes a frame which has a central cavity. A cutter head is arranged in the middle of the frame. The cutter head is connected to a first S-shaped flexible hinge guide plate. The first S-shaped flexible hinge guide plate and a second S-shaped flexible hinge guide plate are arranged oppositely. The first S-shaped flexible hinge guide plate and the second S-shaped flexible hinge guide plate are connected by a connecting block. The connecting block is connected to a power device through a thrust block. The end of the first S-shaped flexible hinge guide plate is connected to the frame, and the end of the second S-shaped flexible hinge guide plate is connected to the frame. Moreover, the stiffness of the first S-shaped flexible hinge guide plate and the second S-shaped flexible hinge guide plate is adjustable. The frame is fixedly provided with a fixed block which is provided with a threaded hole for a double-lead adjusting stud to pass through. Both ends of the double-lead adjusting stud are provided with threads with two different leads. One end of the double-lead adjusting stud is threadedly connected to the fixed block, and the other end of the double-lead adjusting stud is threadedly connected to the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate. By using the axial feed difference generated when the threaded column with different leads rotates one week, the tension and thrust on the S-shaped flexible hinge guide plate are generated, so as to realize the stiffness adjustment of the flexible hinge guide mechanism.

2. The detachable quick tool servo platform with bidirectionally adjustable stiffness according to claim 1, characterized in that, A fastening block is sleeved on the end of the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate, and the fastening block is fixedly connected to the frame.

3. The detachable quick tool servo platform with two-way adjustable stiffness as described in claim 1 is characterized in that, A fastening nut is sleeved on the end of the double-lead adjusting stud, and the fastening nut is in contact with the fixed block.

4. The detachable quick tool servo platform with bidirectionally adjustable stiffness according to claim 1, characterized in that, The first S-shaped flexible hinge guide plate includes a first connecting seat. A plurality of first S-shaped flexible hinges are circumferentially arranged on the outer periphery of the first connecting seat. A first adjusting head is arranged at the end of the first S-shaped flexible hinge, and the first adjusting head is connected to the frame.

5. The detachable quick tool servo platform with bidirectionally adjustable stiffness according to claim 4, characterized in that, The second S-shaped flexible hinge guide plate includes a second connecting seat. A plurality of second S-shaped flexible hinges are circumferentially arranged on the outer periphery of the second connecting seat. A second adjusting head is arranged at the end of the second S-shaped flexible hinge, and the second adjusting head is connected to the frame.

6. The detachable quick tool servo platform with bidirectionally adjustable stiffness according to claim 5, characterized in that, The first S-shaped flexible hinges and the second S-shaped flexible hinges are arranged oppositely one by one, and the connecting block is connected between the first connecting seat and the second connecting seat.

7. The working method of the detachable quick tool servo platform with bidirectionally adjustable stiffness according to any one of claims 1-6, characterized in that, It includes the following steps: After the power device is powered on, it pushes the thrust block. The thrust block pushes the second S-shaped flexible hinge guide plate, and then pushes the first S-shaped flexible hinge guide plate through the connecting block. The two S-shaped flexible hinge guide plates undergo micro-deformation, and then drive the cutter head to achieve a super-large stroke of millimeters and a motion accuracy of micro-nanometers.

8. The working method according to claim 7, characterized in that, During the working process, by rotating the double-lead adjusting stud, due to the different thread leads or pitches of the threads it cooperates with the fixed block and the first S-shaped flexible hinge guide plate / the second S-shaped flexible hinge guide plate, the axial feed difference generated when the double-lead adjusting stud rotates one week generates the tension and thrust on the S-shaped flexible hinge guide plate, realizing the stiffness adjustment of the flexible hinge guide plate.

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