Compact piezoelectric stepping rotation device for extremely low temperature, ultra-high vacuum environment

Abstract

Disclosed is a compact piezoelectric stepping rotation device for an ultra-low temperature, ultra-high vacuum environment, comprising a base, a shell, a cover plate, an elastic member, a piezoelectric ceramic stack, a friction member, a bearing and a connecting shaft, wherein the cover plate and the shell are connected, the elastic member is connected to the base to apply a pre-pressure to the piezoelectric ceramic stack, the connecting shaft is connected to the upper surface of the bearing, passes through the bearing, the friction member and the piezoelectric ceramic stack and is connected to the base, the piezoelectric ceramic stack applies a rotational driving force to the friction member around the connecting shaft when tangential deformation occurs, and the bearing and the friction member form an integral piece.

Description

Technical Field

[0001] This application relates to the field of piezoelectric ceramic stepper motor technology, and more specifically, to a compact piezoelectric stepper rotary device for use in extremely low temperature and ultra-high vacuum environments. Background Technology

[0002] In extremely low temperature and ultra-high vacuum environments, the measurement of physical properties plays a crucial role in research in condensed matter physics and other fields due to the lower thermal noise and the ability to observe information about materials closer to their ground state.

[0003] With the development of mechatronics, piezoelectric ceramic stepper motors are playing an increasingly important role in electromechanical conversion, such as adjusting the orientation of samples in low-temperature physical property measurements.

[0004] However, known piezoelectric ceramic stepper motors are too large, which in turn leads to an excessively large overall size for extremely low temperature and ultra-high vacuum environments, resulting in very high overall costs.

[0005] Therefore, a compact piezoelectric stepping rotary device suitable for extremely low temperature and ultra-high vacuum environments is needed. Summary of the Invention

[0006] To address the aforementioned technical problems, this application is proposed. An embodiment of this application provides a compact piezoelectric stepping rotary device for extremely low temperature and ultra-high vacuum environments, comprising a base, a housing, a cover plate, an elastic element, a piezoelectric ceramic stack, a friction element, a bearing, and a connecting shaft. The cover plate and the housing are connected. The elastic element is connected to the base and applies a preload to the piezoelectric ceramic stack. The connecting shaft is connected to the upper surface of the bearing and passes through the bearing, the friction element, and the piezoelectric ceramic stack to connect to the base. When the piezoelectric ceramic stack undergoes tangential deformation, it applies a rotational driving force to the friction element around the connecting shaft. The bearing and the friction element constitute a single integral component.

[0007] In one embodiment of this application, the bearing is made of zirconium oxide.

[0008] In one embodiment of this application, the connecting shaft and the base have inclined surfaces at the same angle to prevent relative rotation between them.

[0009] In one embodiment of this application, the compact piezoelectric stepping rotary device further includes a piezoelectric ceramic element connector for connecting a plurality of the piezoelectric ceramic stacks disposed thereon.

[0010] In one embodiment of this application, the elastic element is spaced apart from the piezoelectric ceramic stack by at least one spacer and a pre-stress is applied to the piezoelectric ceramic stack by the spacer.

[0011] In one embodiment of this application, the compact piezoelectric stepping rotary device further includes an angle acquisition device for determining the rotation angle of the bearing. The angle acquisition device includes a brush fixed to the inner surface of the cover plate and a resistor connected to the upper surface of the connecting shaft. The brush can slide on the resistor to acquire the rotation angle of the bearing.

[0012] Compared with the prior art, the compact piezoelectric stepping rotation device according to the embodiments of this application can drive the friction element to rotate through inertial stepping or step-by-step stepping by a tangentially deformed piezoelectric ceramic stack and a friction element; the bearing and the friction element are integrated to improve space utilization; the bearing can be used to stabilize the rotation axis of the piezoelectric ceramic stack and the friction element; the elastic element provides preload to the piezoelectric ceramic stack, and the spacer limits the degree of freedom of the piezoelectric ceramic stack in the direction perpendicular to the axis. Attached Figure Description

[0013] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0014] Figure 1 illustrates a schematic diagram of the overall structure of a piezoelectric stepping rotary device according to an embodiment of this application.

[0015] Figure 2 illustrates a cross-sectional schematic diagram of the compact piezoelectric stepping rotary device shown in Figure 1.

[0016] Figure 3 illustrates a structural schematic diagram of the elastic element and base of a piezoelectric stepping rotary device according to an embodiment of this application.

[0017] Figure 4 illustrates a schematic diagram of the structure of the piezoelectric ceramic stack and friction element of a piezoelectric stepping rotary device according to an embodiment of this application.

[0018] Figure 5 illustrates a structural schematic diagram of the bearing and friction element of a piezoelectric stepping rotary device according to an embodiment of this application.

[0019] Figure 6 illustrates a structural schematic diagram of the connecting shaft, friction element, piezoelectric ceramic stack, and piezoelectric ceramic element connector of a piezoelectric stepping rotary device according to an embodiment of this application.

[0020] Figure 7 illustrates a schematic diagram of the connection between the connecting shaft and the base of a piezoelectric stepping rotary device according to an embodiment of this application.

[0021] Figure 8 illustrates a structural schematic diagram of an angle acquisition device for a piezoelectric stepping rotation device according to an embodiment of this application.

[0022] List of reference numerals

[0023] 10 bases

[0024] 15. Outer shell

[0025] 20 Cover plate

[0026] 25 shrapnel

[0027] 30 ceramic balls

[0028] 35 Piezoelectric ceramic element connectors

[0029] 40 Piezoelectric ceramic stack

[0030] 45 Friction Plate

[0031] 50 bearings

[0032] 51 ball bearings

[0033] 55 Connecting shaft

[0034] 60 brushes

[0035] 65 Resistor Positioning Piece Detailed Implementation

[0036] Hereinafter, exemplary embodiments according to this application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein.

[0037] Application Overview

[0038] As mentioned above, piezoelectric ceramic stepper motors are playing an increasingly important role in electromechanical conversion, especially in extremely low temperature and ultra-high vacuum environments. However, currently known piezoelectric ceramic stepper motors are too large, resulting in very high overall costs for property measurements in extremely low temperature and ultra-high vacuum environments.

[0039] To address this technical problem, the basic concept of this application is to propose a compact piezoelectric ceramic stepping and rotating device suitable for extremely low temperature and ultra-high vacuum environments. By causing tangential deformation of the piezoelectric ceramic stack, the friction component is driven to rotate in an inertial stepping or step-by-step manner. Through the integrated design of the bearing and the friction component, the structure is compact and the volume is reduced.

[0040] After introducing the basic principles of this application, various non-limiting embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0041] Exemplary device

[0042] Figure 1 illustrates an overall structural schematic diagram of a compact piezoelectric stepping rotary device 100 for extremely low temperature and ultra-high vacuum environments according to an embodiment of this application, and Figure 2 illustrates a cross-sectional schematic diagram of the piezoelectric stepping rotary device 100 shown in Figure 1.

[0043] As shown in Figure 1, the piezoelectric stepping rotary device 100 includes, from bottom to top, a base 10, a housing 15, and a cover plate 20. The base 10 is detachably connected to the housing 15. The housing 15 is detachably connected to the cover plate 20.

[0044] As shown in Figure 2, the piezoelectric stepping rotary device 100 also includes a spring 25, a ceramic ball 30, a piezoelectric ceramic element connector 35, a piezoelectric ceramic stack 40, a friction plate 45, a bearing 50, a connecting shaft 55, a brush 60, and a resistor positioning plate 65.

[0045] As shown in Figure 2, the spring piece 25 is located on the base 10. Specifically, as shown in Figure 3, the spring piece 25 is fixed to the base 10 on one side, and a ceramic ball 30 is provided on the other side. Returning to Figure 2, the spring piece 25 is spaced apart from the piezoelectric ceramic element connector 35 by the ceramic ball 30. The piezoelectric ceramic element connector 35 applies a preload to the base 10 through the spring piece 25, and limits the degree of freedom of the piezoelectric ceramic element in the direction perpendicular to the axis while providing the preload through the ceramic ball 30. In this embodiment, the spring piece 25 is a beryllium copper spring piece.

[0046] As shown in Figures 2 and 4, the piezoelectric ceramic element connector 35 is connected to the piezoelectric ceramic stack 40 to form a piezoelectric ceramic stack 40 from multiple piezoelectric ceramic elements.

[0047] As shown in Figures 2 and 4, the piezoelectric ceramic stack 40 is fixedly connected to the friction plate 45. When tangential deformation occurs, but is not limited to tangential deformation, the piezoelectric ceramic elements constituting the piezoelectric ceramic stack 40 push the friction plate 45 around the rotation axis, applying a rotational driving force to the friction plate 45.

[0048] As shown in Figures 2 and 5, the friction plate 45 and the bearing 50 are fixedly connected. Preferably, the friction plate 45 and the bearing 50 are integrated to improve space utilization. The bearing has balls 51. Under the rotational driving force applied by the piezoelectric ceramic element, the friction plate 45 rotates, driving the bearing 50 to rotate. In one embodiment, the bearing 50 is a thrust bearing, preferably an irregularly shaped thrust bearing. In one embodiment, the bearing 50 is made of zirconium oxide.

[0049] As shown in Figures 2, 6, and 7, the connecting shaft 55 is connected to the upper surface of the bearing 50 and passes through the bearing 50, friction plate 45, piezoelectric ceramic stack 40, and piezoelectric ceramic element connector 35 to connect to the base 10. Preferably, the connecting shaft 55 and the base 10 are connected by a central thread. The connecting shaft 55 and the base 10 prevent relative rotation between them by a shape-fitting arrangement. Preferably, as shown in Figures 6 and 7, the connecting shaft 55 and the base 10 have bevels of the same angle to prevent relative rotation between them.

[0050] As shown in Figures 2 and 8, the resistor positioning plate 65 is connected to the upper surface of the connecting shaft 55 (i.e., the surface of the connecting shaft 55 facing away from the bearing 50 and friction plate 45), and the brush 60 is fixed to the inner surface of the cover plate 20 (i.e., the side surface facing the connecting shaft 55, bearing 50, and friction plate 45). The brush 60 slides on the resistor positioning plate 65 to read angle information and realize closed-loop control. In this embodiment, the annular resistor plate and the brush are used to read the angle to realize closed-loop control, but it is not limited to this. For example, the resistor positioning plate may not be annular, but may be strip-shaped, rhomboid, etc.

[0051] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0052] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A compact piezoelectric stepping rotary device for extremely low temperature and ultra-high vacuum environments, comprising a base, a housing, a cover plate, an elastic element, a stack of piezoelectric ceramics, a friction element, a bearing, and a connecting shaft, wherein, The cover plate is connected to the outer shell, the elastic element is connected to the base, and a preload is applied to the piezoelectric ceramic stack. The connecting shaft is connected to the upper surface of the bearing and passes through the bearing, the friction element and the piezoelectric ceramic stack to connect to the base. When the piezoelectric ceramic stack undergoes tangential deformation, it applies a rotational driving force to the friction element around the connecting shaft. The bearing and the friction element form an integral part.

2. The compact piezoelectric stepping rotary device as described in claim 1, wherein, The bearing is made of zirconium oxide.

3. The compact piezoelectric stepping rotary device as described in claim 1, wherein, The connecting shaft and the base have the same angled slope to prevent relative rotation between them.

4. The compact piezoelectric stepping rotary device of claim 1 further includes a piezoelectric ceramic element connector for connecting a plurality of said piezoelectric ceramic stacks disposed thereon.

5. The compact piezoelectric stepping rotary device as described in claim 1, wherein, The elastic element is spaced apart from the piezoelectric ceramic stack by at least one spacer and defines the piezoelectric ceramic stack in a degree of freedom perpendicular to the axis.

6. The compact piezoelectric stepping rotary device as described in claim 1, further comprising an angle acquisition device for determining the rotation angle of the bearing. in, The angle acquisition device includes a brush fixed to the inner surface of the cover plate and a resistor connected to the upper surface of the connecting shaft. The brush can slide on the resistor to obtain the rotation angle of the bearing.

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