Large radial displacement, high bandwidth piezoelectric optical fiber stretcher

Abstract

A kind of piezoelectric optical fiber stretcher of large radial displacement, high bandwidth, including stretch ring, rhombus ring with displacement amplification function inside stretch ring, piezoelectric stack with interference fit installed in rhombus ring;Stretch ring includes fixed mounting hole, rigid component around mounting hole, flexible hinge, circular ring structure with optical fiber winding groove;Rhombus ring short axis direction is close to the end of the center of stretch ring and is connected with rigid component;Rhombus ring short axis direction is away from the end of the center of stretch ring and is connected with circular ring structure;Rigid component and circular ring structure are also connected by flexible hinge;Optical fiber can be wound in optical fiber winding groove in multiple turns;When optical fiber needs to be stretched, positive voltage is applied to piezoelectric stack, piezoelectric stack is elongated, rhombus ring pushes circular ring structure to produce deformation, stretches optical fiber, changes the cavity length of optical fiber.The present application has the characteristics of large radial displacement, high working bandwidth etc.

Description

Technical Field

[0001] This invention relates to the field of piezoelectric material actuator technology, specifically to a piezoelectric fiber stretcher with large radial displacement and high bandwidth. Background Technology

[0002] Micro-displacement actuation is a core technology in fields such as scientific instruments, precise pointing of spacecraft, materials engineering, and high-precision machining. Currently, piezoelectric materials are mostly used to perform core actuation tasks, playing an important role in stretching optical fibers and changing the cavity length of optical fibers. However, when piezoelectric materials work with mechanisms to stretch optical fibers, they often face problems such as insufficient driving displacement and low operating bandwidth, and are easily affected by environmental noise. At the same time, piezoelectric ceramics are brittle materials and are prone to fracture. Piezoelectric stacks are extremely prone to fracture under impact loads, leading to the failure of the entire actuator. Summary of the Invention

[0003] In order to solve the problems existing in the prior art, the purpose of this invention is to provide a piezoelectric fiber stretcher with large radial displacement and high bandwidth, which provides an effective solution to the difficulties such as insufficient driving displacement, low working bandwidth and easy breakage of ceramics.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A piezoelectric fiber stretcher with large radial displacement and high bandwidth includes a stretching ring 1, a rhombic ring 1-3 with displacement amplification function located inside the stretching ring, and a piezoelectric stack 2 interference-fitted inside the rhombic ring 1-3, the height direction of the piezoelectric stack 2 being parallel to the long axis of the rhombic ring 1-3; the stretching ring 1 includes a mounting hole 1-1, a rigid component 1-2 surrounding the mounting hole 1-1, a flexible hinge 1-4, and a ring structure 1-6 with fiber winding groove 1-5; one end of the rhombic ring 1-3 near the center of the stretching ring 1 is connected to the rigid component 1-2; the rhombic ring 1... -3 The end of the piezoelectric fiber stretcher located away from the center of the stretching ring 1 along its short axis is connected to the annular structure 1-6; the rigid component 1-2 and the annular structure 1-6 are connected by a flexible hinge 1-4; the optical fiber is wound in the optical fiber winding groove 1-5; when the optical fiber needs to be stretched, a positive voltage is applied to the piezoelectric stack 2, causing the piezoelectric stack 2 to elongate, and the diamond ring 1-3 pushes the annular structure 1-6 to deform, stretching the optical fiber and changing the cavity length of the optical fiber; the piezoelectric stack 2 has the characteristic that applying voltage will cause displacement along the height direction, and the elongation of the piezoelectric stack 2 is controlled by voltage to achieve the effect of high-precision control of the piezoelectric optical fiber stretcher in stretching the optical fiber. The piezoelectric optical fiber stretcher of the present invention has the characteristics of large radial displacement and high working bandwidth.

[0006] The rhombic ring 1-3 has the function of displacement amplification. When the piezoelectric fiber stretcher is working, the displacement change of the rhombic ring 1-3 in the short axis direction is greater than the displacement change of the piezoelectric stack 2. When the piezoelectric stack 2 is elongated, the distance between the center of the short axis of the rhombic ring 1-3 and the center of the stretching ring 1 increases, and the annular structure 1-6 moves away from the center, which improves the radial displacement of the piezoelectric fiber stretcher.

[0007] The stiffness of the flexible hinge 1-4 in the long axis and thickness direction of the rhombic ring 1-3 is much greater than that in the short axis direction of the rhombic ring 1-3. This helps to improve the bending mode frequency of the piezoelectric fiber stretcher along the thickness direction and the torsional mode frequency along the center of the piezoelectric fiber stretcher, thereby increasing the working bandwidth of the piezoelectric fiber stretcher.

[0008] The flexible hinges 1-4 are arranged in a multi-stage manner. Under the premise of ensuring that the overall stiffness of the flexible hinges 1-4 in the direction of the short axis of the rhomboid rings 1-3 remains unchanged, the torsional stiffness of the piezoelectric fiber stretcher can be improved by adding multiple stages of flexible hinges. This helps to increase the torsional mode frequency of the piezoelectric fiber stretcher along the center of the piezoelectric fiber stretcher and improve the working bandwidth of the piezoelectric fiber stretcher.

[0009] The end of the rhombic ring 1-3 near the center of the tension ring 1 along its short axis is connected to the rigid component 1-2. Compared with the assembly method where the end of the rhombic ring 1-3 near the center of the tension ring 1 along its long axis is connected to the rigid component 1-2, the stress level of the piezoelectric stack 2 is smaller under the same impact load along the thickness direction of the tension ring 1.

[0010] The number of the fixed mounting holes 1-1, rhomboid rings 1-3, flexible hinges 1-4, and piezoelectric stacks 2 is not limited.

[0011] The circular ring structure 1-6 is composed of multiple sector-shaped circular ring structures with gaps between them. The presence of these gaps allows the sector-shaped circular ring structures to reciprocate as the applied voltage changes.

[0012] The circular structure 1-6 reduces mass and enhances rigidity by adding holes 1-7 and ribs in the middle, which helps to increase the modal frequency of the piezoelectric fiber stretcher and improve the working bandwidth of the fiber stretcher.

[0013] The magnification of the rhomboid rings 1-3 is 1.5 to 2.5 times.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1) Compared with the traditional method of using a single piezoelectric stack to stretch optical fibers, this invention has the characteristics of large optical fiber stretching displacement and low piezoelectric stack ceramic stress level under impact load due to the addition of the annular structure 1-6 and the rhombic ring 1-3.

[0016] 2) Compared with the traditional piezoelectric stack mechanism for stretching optical fibers, the piezoelectric fiber stretcher has a large radial displacement due to the design of a rhomboid ring with displacement amplification function; at the same time, the modal frequency of the piezoelectric fiber stretcher is increased by increasing the stiffness in a specific direction and reducing the mass through graded flexible hinges 1-4, holes 1-7 and ribs, thereby increasing the working bandwidth of the piezoelectric fiber stretcher. Therefore, the piezoelectric fiber stretcher of the present invention has the characteristics of large radial displacement and high working bandwidth. Attached Figure Description

[0017] Figure 1 This is a structural diagram of the piezoelectric fiber stretcher of the present invention.

[0018] Figure 2 This is a partial view of the piezoelectric fiber stretcher of the present invention. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] like Figure 1 As shown, this invention discloses a piezoelectric fiber stretcher with large radial displacement and high bandwidth. The stretcher includes a stretching ring 1, a piezoelectric stack 2 located inside the stretching ring, and a rhombus-shaped ring 1-3 with displacement amplification function. The stretching ring 1 includes a mounting hole 1-1, a rigid component 1-2 surrounding the mounting hole 1-1, the rhombus-shaped ring 1-3 with displacement amplification function, a flexible hinge 1-4, and a ring structure 1-6 with fiber winding grooves 1-5. The end of the rhombus-shaped ring 1-3 near the center of the stretching ring 1 along its short axis is connected to the rigid component 1-2; the end of the rhombus-shaped ring 1-3 away from the center of the stretching ring 1 along its short axis is connected to the ring structure 1-6. 1-2 and the annular structure 1-6 are connected by a flexible hinge 1-4; the piezoelectric stack 2 is installed inside the rhomboid ring 1-3, and the fit between the piezoelectric stack 2 and the rhomboid ring 1-3 is an interference fit. The height direction of the piezoelectric stack 2 is parallel to the long axis direction of the rhomboid ring 1-3; the optical fiber is wound in the optical fiber winding groove 1-5; when it is necessary to stretch the optical fiber, a positive voltage is applied to the piezoelectric stack 2, the piezoelectric stack 2 elongates, the rhomboid ring 1-3 pushes the annular structure 1-6 to deform, stretching the optical fiber and changing the cavity length of the optical fiber; the piezoelectric stack 2 has the characteristic that applying voltage will cause displacement along the height direction. By controlling the elongation of the piezoelectric stack 2 by voltage, the effect of stretching the optical fiber by the piezoelectric optical fiber stretcher with high precision can be achieved.

[0021] In a preferred embodiment of the present invention, the rhombic ring 1-3 has a displacement amplification function, with an amplification factor of 1.5 to 2.5 times. When the piezoelectric fiber stretcher is working, the displacement change of the rhombic ring 1-3 in the short axis direction is 1.5 to 2.5 times that of the displacement change of the piezoelectric stack 2. When the piezoelectric stack 2 is elongated, the distance between the center of the short axis of the rhombic ring 1-3 and the center of the stretching ring 1 increases, and the annular structure 1-6 moves away from the center, thereby increasing the radial displacement of the piezoelectric fiber stretcher.

[0022] In a preferred embodiment of the present invention, the stiffness of the flexible hinge 1-4 in the long axis direction and thickness direction of the rhombic ring 1-3 is at least one order of magnitude greater than the stiffness of the flexible hinge 1-4 in the short axis direction of the rhombic ring 1-3. This helps to improve the bending mode frequency along the thickness direction of the piezoelectric fiber stretcher and the torsional mode frequency along the center of the piezoelectric fiber stretcher, thereby increasing the working bandwidth of the piezoelectric fiber stretcher.

[0023] In a preferred embodiment of the present invention, the flexible hinges 1-4 are arranged in a two-stage manner. While ensuring that the overall stiffness of the flexible hinges 1-4 remains unchanged in the direction of the short axis of the rhomboid rings 1-3, the space occupancy rate is also considered. By arranging the flexible hinges in a two-stage manner, the torsional stiffness of the piezoelectric fiber stretcher is improved, which helps to increase the torsional mode frequency of the piezoelectric fiber stretcher along the center of the piezoelectric fiber stretcher and improve the working bandwidth of the piezoelectric fiber stretcher.

[0024] In a preferred embodiment of the present invention, the end of the rhombic ring 1-3 near the center of the stretching ring 1 in the short axis direction is connected to the rigid component 1-2. Compared with the assembly method in which the end of the rhombic ring 1-3 near the center of the stretching ring 1 in the long axis direction is connected to the rigid component 1-2, the stress level of the piezoelectric stack 2 is smaller under the same impact load along the thickness direction of the stretching ring 1.

[0025] In a preferred embodiment of the present invention, the number of fixed mounting holes 1-1 is 3, the number of rhomboid rings 1-3 is 3, which are evenly distributed on the tension ring 1, the number of two-stage hinge structures 1-4 is 6, and the number of piezoelectric stacks 2 is 3.

[0026] In a preferred embodiment of the present invention, the annular structure 1-6 is composed of three sector-shaped annular structures with gaps between them. The presence of these gaps allows the sector-shaped annular structures to reciprocate as the applied voltage changes.

[0027] In a preferred embodiment of the present invention, the annular structure 1-6 reduces mass and enhances rigidity by adding 12 holes 1-7 and 4 ribs, which helps to increase the modal frequency of the piezoelectric fiber stretcher and improve the working bandwidth of the fiber stretcher.

Claims

1. A piezoelectric fiber stretcher with large radial displacement and high bandwidth, characterized in that: The stretcher includes a stretching ring (1), a rhombus ring (1-3) with displacement amplification function located inside the stretching ring, and a piezoelectric stack (2) installed in the rhombus ring (1-3) with interference fit. The height direction of the piezoelectric stack (2) is parallel to the long axis of the rhombus ring (1-3). The stretching ring (1) includes a mounting hole (1-1), a rigid component (1-2) around the mounting hole (1-1), a flexible hinge (1-4), and a ring structure (1-6) with an optical fiber winding groove (1-5). The end of the rhombus ring (1-3) near the center of the stretching ring (1) is connected to the rigid component (1-2) in the short axis direction. The end away from the center of the stretching ring (1) is connected to the annular structure (1-6); the rigid component (1-2) and the annular structure (1-6) are connected by a flexible hinge (1-4); the optical fiber is wound in the optical fiber winding groove (1-5); when the optical fiber needs to be stretched, a positive voltage is applied to the piezoelectric stack (2), the piezoelectric stack (2) elongates, the diamond ring (1-3) pushes the annular structure (1-6) to deform, stretching the optical fiber and changing the cavity length of the optical fiber; the piezoelectric stack (2) has the characteristic that applying voltage will cause displacement along the height direction, and the elongation of the piezoelectric stack (2) is controlled by voltage to achieve the effect of high-precision control of the piezoelectric optical fiber stretcher to stretch the optical fiber.

2. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The rhombic ring (1-3) has the function of displacement amplification. When the piezoelectric fiber stretcher is working, the displacement change of the short axis of the rhombic ring (1-3) is greater than the displacement change of the piezoelectric stack (2). When the piezoelectric stack (2) is elongated, the distance between the center of the short axis of the rhombic ring (1-3) and the center of the stretching ring (1) increases, and the annular structure (1-6) moves away from the center, which improves the radial displacement of the piezoelectric fiber stretcher.

3. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The stiffness of the flexible hinge (1-4) in the long axis and thickness direction of the rhombic ring (1-3) is much greater than that of the flexible hinge (1-4) in the short axis direction of the rhombic ring (1-3). This helps to improve the bending mode frequency of the piezoelectric fiber stretcher along the thickness direction and the torsional mode frequency along the center of the piezoelectric fiber stretcher, thereby increasing the working bandwidth of the piezoelectric fiber stretcher.

4. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The flexible hinge (1-4) is arranged in a multi-level manner. Under the premise of ensuring that the overall stiffness of the flexible hinge (1-4) in the direction of the short axis of the rhomboid ring (1-3) remains unchanged, the torsional stiffness of the piezoelectric fiber stretcher can be improved by adding a multi-level flexible hinge. This helps to increase the torsional mode frequency of the piezoelectric fiber stretcher along the center of the piezoelectric fiber stretcher and improve the working bandwidth of the piezoelectric fiber stretcher.

5. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The end of the rhombic ring (1-3) near the center of the stretching ring (1) in the short axis direction is connected to the rigid component (1-2). Compared with the assembly method where the end of the rhombic ring (1-3) near the center of the stretching ring (1) in the long axis direction is connected to the rigid component (1-2), the stress level of the piezoelectric stack (2) is smaller when subjected to the same impact load along the thickness direction of the stretching ring (1).

6. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The number of mounting holes (1-1), rhomboid rings (1-3), flexible hinges (1-4), and piezoelectric stacks (2) is not limited.

7. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The annular structure (1-6) is composed of multiple fan-shaped annular structures with gaps between them.

8. The piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The circular structure (1-6) reduces mass and enhances rigidity by adding holes (1-7) and ribs in the middle, which helps to increase the modal frequency of the piezoelectric fiber stretcher and improve the working bandwidth of the fiber stretcher.

9. A piezoelectric fiber stretcher with large radial displacement and high bandwidth according to claim 1, characterized in that: The magnification of the rhomboid rings (1-3) is 1.5 to 2.5 times.

Images