Piezoelectric stack driving rotating motor

Abstract

The invention provides a piezoelectric stack driven rotating electric machine. The invention relates to the field of motors. The motor comprises a shell, a base, an upper cover and an end cover, the base is fixedly connected with a rotary supporting shaft through a first bearing. The top end of the rotary supporting shaft is connected with the center of the bottom of the U-shaped supporting rod. The upper part of a bottom rod of the U-shaped supporting rod is connected with the first piezoelectric stack; the top of the U-shaped supporting rod fixes the hinge lever element through a limiting supporting shaft. The two sides of the top of the hinge lever element are fixedly connected with clamping block elements. Pushing blocks are fixed to the two sides of the bottom of the hinge lever element. The top of the clamping block element is embedded with the outer edge of the rotor; the rotor is clamped and loosened through the two arc-shaped clamping block elements. According to the piezoelectric stack driving rotating motor, one piezoelectric stack acts on the side face of the U-shaped supporting rod, so that the U-shaped supporting rod drives the hinge lever element to rotate, motor rotation is achieved, the service life of the motor is prolonged, and the transmission efficiency of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the field of motors, and in particular to a piezoelectric stack driven rotating motor. Background Art

[0002] Piezoelectric motors use the inverse piezoelectric effect of piezoelectric elements to convert the microscopic deformation of materials into macroscopic rotation of the rotor through resonance amplification and coupled motion. They can produce stable motion with nanometer resolution and millimeter range, and have rapid response, certain load capacity and a wide speed range. They have good research prospects in many fields that have high requirements for ultra-precision positioning and manipulation technologies, such as bioengineering, aerospace, and micro-robotics.

[0003] The piezoelectric stack drives the rotating motor. In the piezoelectric stack driven stepping rotating motor with the publication number CN113162465A, two piezoelectric stacks in the driving mechanism are staggered along the axial direction of the motor, acting on two beams at different heights respectively, so that the arc-shaped displacement amplifying element can be controlled individually to realize the forward and reverse rotation of the motor.

[0004] Existing piezoelectric stacks usually output linear motion, and generally require a mechanical mechanism to convert the linear motion into rotational motion. The friction between the stator and the rotor involved in the rotational motion will consume energy, thereby reducing torque and shortening service life. These factors affect the application of piezoelectric stack-driven rotating motors in actual production and life. Summary of the invention

[0005] According to the above-mentioned technical problem that driving a piezoelectric motor requires multiple piezoelectric clamping mechanisms, which is complex in structure and has high manufacturing cost, a piezoelectric stack driven rotating motor is provided. The present invention mainly uses the lever principle to achieve the clamping and loosening of the rotor. When the piezoelectric stack is not working, the motor is self-locked, which can prevent the motor from rotating due to external force, and ensure the motor's requirement for precise positioning.

[0006] The technical means adopted by the present invention are as follows:

[0007] A piezoelectric stack driven rotating motor comprises: a housing, a base, an upper cover and an end cover; the bottom of the housing is fixed to the top outer ring of the base; the top of the housing is connected and fixed with the upper cover and the end cover in sequence;

[0008] A rotating support shaft is fixedly connected to the base via a first bearing; the top end of the rotating support shaft is connected to the bottom center of the U-shaped support rod; the upper part of the bottom rod of the U-shaped support rod is connected to the first piezoelectric stack; the bottom of the U-shaped support rod is located inside the piezoelectric stack base and the spring base, and a second piezoelectric stack and a spring are respectively provided; the top of the U-shaped support rod fixes the hinge lever element via a limiting support shaft; clamping block elements are fixedly connected to both sides of the top of the hinge lever element; push blocks are fixed to both sides of the bottom of the hinge lever element;

[0009] A rotor is arranged at the bottom of the upper cover; a second bearing is arranged at the center of the upper cover; the bottom of the second bearing realizes axial limitation of the rotor through a second elastic retaining ring and the upper cover; and the top of the second bearing is fixed by an end cover.

[0010] Furthermore, the top opposite sides of the two crossed hinge lever elements are fixedly connected by a tension spring.

[0011] Furthermore, the clamping block element is arc-shaped; the top of the clamping block element is engaged with the outer edge of the rotor; and the rotor is clamped and released by two arc-shaped clamping block elements.

[0012] Furthermore, a rotating support shaft is fixedly connected to the base via two first bearings; the bottom of the first bearing is axially positioned by a first elastic retaining ring; the upper part of the first bearing is positioned by a shaft shoulder, and a sleeve is provided between the two first bearings.

[0013] Furthermore, two second bearings are provided at the center of the upper cover; and a sleeve is provided between the second bearings.

[0014] Furthermore, the hinge lever element is composed of two parallelogram rods, one of which is thicker than the other and has a slot in the middle, through which the other rod passes, holes are drilled at the overlapping positions of the two rods, and tension springs are connected to the two rods, through which the two rods realize lever movement with the first piezoelectric stack.

[0015] Furthermore, the shell, base, upper cover and end cover are connected and fixed by screws.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. A piezoelectric stack driven rotating motor provided by the present invention realizes the clamping and loosening of the rotor by utilizing the lever principle. When the piezoelectric stack is not working, the motor is self-locked, which can prevent the motor from rotating due to external force, thereby ensuring the motor's requirement for precise positioning.

[0018] 2. The piezoelectric stack of the present invention drives the rotating motor, which is simple to control. By alternately applying square wave signals with a phase difference of T / 2 to two piezoelectric stacks, continuous forward and reverse rotation of the motor can be achieved.

[0019] 3. The piezoelectric stack of the present invention drives the rotating motor, and adopts two arc-shaped clamping block elements to increase the contact area with the rotor, reduce the temperature rise of the motor caused by the friction between the clamping block and the rotor, and improve the service life and transmission efficiency of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0022] Figure 2 For the present invention Figure 1 Schematic diagram of the explosion structure.

[0023] Figure 3 It is a structural diagram of the drive system of the present invention.

[0024] Figure 4 When the present invention is in the initial state Figure 1 AA View

[0025] Figure 5 This is a working principle diagram of the motor of the present invention when it rotates counterclockwise at 0-T / 2 time;

[0026] Figure 6 This is a working principle diagram of the motor of the present invention when it rotates counterclockwise during the T / 2-T time;

[0027] Figure 7 This is a working principle diagram of the T-2T time when the motor of the present invention rotates counterclockwise;

[0028] Figure 8 This is a working principle diagram of the motor of the present invention when it rotates clockwise at 0-T / 2 time;

[0029] Fig. 9 This is a working principle diagram of the motor of the present invention when it rotates clockwise during the T / 2-T time;

[0030] Fig.10 This is a working principle diagram of the T-2T time when the motor of the present invention rotates clockwise;

[0031] Fig.11This is a diagram of the voltage applied to the two piezoelectric stacks when the motor of the present invention rotates counterclockwise;

[0032] Fig.12 This is a diagram of the voltage applied to the two piezoelectric stacks when the motor of the present invention rotates clockwise.

[0033] In the figure: 1, housing; 2, first screw; 3, base; 4, first elastic retaining ring; 5, first bearing; 6, sleeve; 7, rotating support shaft; 8, spring base; 9, spring; 10, spring base upper cover; 11, push block; 11-1, first push block; 11-2, second push block; 12, first piezoelectric stack; 13, limit sleeve; 14, second screw; 15, clamping block element; 15-1, first clamping block element; 15-2, second clamping block element; 16 , rotor; 17, upper cover; 18, third screw; 19, end cover; 20, fourth screw; 21, sleeve; 22, second bearing; 23, second elastic retaining ring; 24, tension spring; 25, hinge lever element; 26, nut; 27, limit support shaft; 28, U-shaped support rod; 29, fifth screw; 30, sixth screw; 31, seventh screw; 32, piezoelectric stack base upper cover; 33, second piezoelectric stack; 34, piezoelectric stack base; 35, eighth screw. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0037] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0038] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0039] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0040] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0041] like Figure 1-3As shown, the present invention provides a piezoelectric stack driven rotating motor, comprising: a housing 1, a base 3, an upper cover 17 and an end cover 19; the bottom of the housing is fixed to the top outer ring of the base; the top of the housing is connected and fixed with the upper cover 17 and the end cover 19 by a third screw 18 and a fourth screw 20;

[0042] A rotating support shaft 7 is fixedly connected to the base via a first bearing 5; the top of the rotating support shaft 7 is connected to the bottom center of the U-shaped support rod 28; the upper part of the bottom rod of the U-shaped support rod 28 is connected to the first piezoelectric stack 12; the bottom of the U-shaped support rod 28 is located inside the piezoelectric stack base 34 and the spring base 8, and a second piezoelectric stack 33 and a spring 9 are respectively provided; the top of the U-shaped support rod 28 fixes the hinge lever element 25 via a limiting support shaft 27; clamping block elements 15 are fixedly connected to both sides of the top of the hinge lever element 25; push blocks 11 are fixed to both sides of the bottom of the hinge lever element 25; the opposite sides of the top of the two crossed hinge lever elements 25 are fixedly connected via tension springs 24.

[0043] A rotor 16 is disposed at the bottom of the upper cover; a second bearing 22 is disposed at the center of the upper cover 17; the bottom of the second bearing 22 is axially limited to the rotor 16 through a second elastic retaining ring 23 and the upper cover 17; the top of the second bearing 22 is fixed by an end cover 19.

[0044] The clamping block element 15 is arc-shaped; the top of the clamping block element 15 is engaged with the outer edge of the rotor 16; the rotor 16 is clamped and released by two arc-shaped clamping block elements 15.

[0045] The base is fixedly connected with a rotating support shaft 7 via two first bearings 5; the bottom of the first bearing 5 is axially positioned by a first elastic retaining ring 4; the upper part of the first bearing 5 is positioned by a shaft shoulder, and a sleeve 6 is provided between the two first bearings 5; two second bearings 22 are provided at the center of the upper cover 17; a sleeve 21 is provided between the second bearings 22; the housing 1, the base 3, the upper cover 17 and the end cover 19 are connected and fixed by screws.

[0046] The shell 1 is fixed to the base 3 by the first screw 2; the piezoelectric stack base 34 and the spring base 8 are connected to the base 3 by the eighth screw 35; the first piezoelectric stack 12 is vertically fixedly connected to the U-shaped support rod 28 by the sixth screw 30; the upper end of the U-shaped support rod 28 is connected to the limited support shaft 27 by a threaded connection; the limited support shaft 27 is a stepped shaft; the hinge lever element 25 is sleeved on its thinner shaft end and fixed by a nut 26, so that the hinge lever element 25 is located in the middle position of the limited support shaft 27; the hinge lever element 25 is composed of two parallelogram rods, one of which is thicker than the other, and a slot is provided in the middle position, the other rod passes through the slot, and holes are drilled at the overlapping position of the two rods, and the two rods are connected with tension springs 24, and the two rods realize lever movement with the first piezoelectric stack 12 through the tension springs 24.

[0047] The first push block 11-1 and the second push block 11-2 are fixed to the outer sides of the lower end of the hinge lever element 25 by the fifth screw 29, and the bottoms of the two push blocks are flush. A second piezoelectric stack 33 and a spring 9 are distributed on both sides of one side of the U-shaped support rod 28, and are respectively placed in the piezoelectric stack seat 34 and the spring base 8. The piezoelectric stack seat upper cover 32 and the spring base upper cover 10 are respectively covered on the piezoelectric stack seat 34 and the spring base 8, and are fixed by the seventh screw 31; the second piezoelectric stack 33 can apply force to the U-shaped support rod 28, thereby driving the hinge lever element 25 to rotate;

[0048] The spring 9 restores the hinge lever element 25 to its initial equilibrium position; the outer side of the upper end of the hinge lever element 25 is fixedly connected to the first clamping block element 15-1 and the second clamping block element 15-2 by the second screw 14 and the fifth screw 29; and the tops of the two arc-shaped clamping block elements are flush; the contact positions between the first clamping block element 15-1, the second clamping block element 15-2 and the hinge lever element 25 and the second screw 14 and the fifth screw 29 are all polished to ensure planar contact between the two.

[0049] The working process of the piezoelectric stack driving the rotating motor of the present invention is as follows:

[0050] In the initial state, if Figure 3 , 4 As shown, the first piezoelectric stack 12, the second piezoelectric stack 33, and the spring 9 are at their original lengths, the tension spring 24 is in a stretched state, the two push blocks 11 are perpendicular to the first piezoelectric stack 12, the U-shaped support rod 28 is perpendicular to the second piezoelectric stack 33 and the spring 9, and the two arc-shaped clamping block elements 15 and the rotor 16 are in a clamped state and relatively stationary.

[0051] When the motor rotates counterclockwise, Figure 5As shown, within the 0-T / 2 time period, a voltage with a positive bias amplitude of U1 is applied to the second piezoelectric stack 33, and the second piezoelectric stack 33 extends along its axial direction, pushing the U-shaped support rod 28, thereby driving the hinge lever element 25 together with the two arc-shaped clamping block elements 15 to rotate through an angle θ1. At the same time, the two arc-shaped clamping block elements 15 drive the rotor 16 clamped by the tension spring 24 to rotate through an angle θ1.

[0052] like Figure 6 As shown, in the T / 2-T time period, the voltage of the second piezoelectric stack 33 is reduced to 0, and the first piezoelectric stack 12 is supplied with a voltage with a positive bias amplitude of U2. The first piezoelectric stack 12 pushes the push block 11, thereby driving the hinge lever element 25 to perform a lever movement. The tension spring 24 is stretched by the hinge lever element 25 so that the two arc-shaped clamping block elements 15 are out of contact with the rotor 16. The spring 9 pushes the U-shaped support rod 28 to drive the hinge lever element 25 back to the initial position. At time T, the voltage of the first piezoelectric stack 12 is reduced to 0, and the hinge lever element 25 drives the two arc-shaped clamping block elements 15 to clamp the rotor 16 under the action of the tension spring 24, and the system returns to the initial equilibrium state.

[0053] like Figure 7 As shown, in the T-2T time period, the piezoelectric motor repeats the above 0-T time period process, so that the rotor 16 rotates by an angle of 2θ1. Continuously inputting a square wave signal with a positive bias amplitude of U1 to the second piezoelectric stack 33 and a square wave signal with a positive bias amplitude of U2 to the first piezoelectric stack 12 can make the rotor 16 rotate continuously counterclockwise.

[0054] When the motor rotates clockwise, Figure 8 As shown, in the 0-T / 2 time period, a voltage with a negative bias amplitude of U3 is applied to the second piezoelectric stack 33, and the second piezoelectric stack 33 is shortened along its axial direction. The spring 9 pushes the U-shaped support rod 28, thereby driving the hinge lever element 25 together with the two arc-shaped clamping block elements 15 to rotate through an angle θ2. At the same time, the two arc-shaped clamping block elements 15 drive the rotor 16 clamped by the tension spring 24 to rotate through an angle θ2.

[0055] like Fig. 9 As shown, within the T / 2-T time period, the voltage of the second piezoelectric stack 33 is reduced to 0, and a voltage with a positive bias amplitude of U2 is applied to the first piezoelectric stack 12. The first piezoelectric stack 12 pushes the push block 11, thereby driving the hinge lever element 25 to perform a lever movement. The tension spring 24 is stretched by the hinge lever element 25, thereby causing the two arc-shaped clamping block elements 15 to break away from contact with the rotor 16. The second piezoelectric stack 33 pushes the U-shaped support rod 28, thereby driving the hinge lever element 25 to return to the initial position.

[0056] At time T, the voltage of the first piezoelectric stack 12 is reduced to 0, and the hinge lever element 25 drives the two arc-shaped clamping block elements 15 to clamp the rotor 16 under the action of the tension spring 24, and the system returns to the initial equilibrium state.

[0057] like Fig.10 As shown, in the T-2T time period, the piezoelectric motor repeats the above 0-T time period process, so that the rotor 16 rotates by an angle of 2θ2. Repeating the above process, continuously inputting a square wave signal with a negative bias amplitude of U3 to the second piezoelectric stack 33, and inputting a square wave signal with a positive bias amplitude of U2 to the first piezoelectric stack 12, the rotor 16 can be continuously rotated clockwise.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A piezoelectric stack driven rotating motor, characterized in that: include: A shell (1), a base (3), an upper cover (17) and an end cover (19); the bottom of the shell is fixed to the top outer ring of the base; the top of the shell is connected and fixed with the upper cover (17) and the end cover (19) in sequence; A rotating support shaft (7) is fixedly connected to the base via a first bearing (5); the top end of the rotating support shaft (7) is connected to the bottom center of the U-shaped support rod (28); the upper part of the bottom rod of the U-shaped support rod (28) is connected to the first piezoelectric stack (12); the bottom of the U-shaped support rod (28) is located inside the piezoelectric stack base (34) and the spring base (8), and a second piezoelectric stack (33) and a spring (9) are provided respectively; the top of the U-shaped support rod (28) fixes the hinge lever element (25) via a limiting support shaft (27); clamping block elements (15) are fixedly connected to both sides of the top of the hinge lever element (25); push blocks (11) are fixed to both sides of the bottom of the hinge lever element (25); A rotor (16) is arranged at the bottom of the upper cover; a second bearing (22) is arranged at the center of the upper cover (17); the bottom of the second bearing (22) is connected to the upper cover (17) via a second elastic retaining ring (23) to achieve axial positioning of the rotor (16); and the top of the second bearing (22) is fixed via an end cover (19).

2. A piezoelectric stack driven rotating motor according to claim 1, characterized in that: The top opposite sides of the two crossed hinge lever elements (25) are fixedly connected via a tension spring (24).

3. The piezoelectric stack driven rotating motor according to claim 1, characterized in that: The clamping block element (15) is arc-shaped; the top of the clamping block element (15) is embedded with the outer edge of the rotor (16); the rotor (16) is clamped and released by two arc-shaped clamping block elements (15).

4. The piezoelectric stack driven rotating motor according to claim 1, characterized in that: The base is fixedly connected to a rotating support shaft (7) via two first bearings (5); the bottom of the first bearing (5) is axially positioned via a first elastic retaining ring (4); the upper part of the first bearing (5) is positioned via a shaft shoulder, and a sleeve (6) is provided between the two first bearings (5).

5. The piezoelectric stack driven rotating motor according to claim 1, characterized in that: Two second bearings (22) are provided at the center of the upper cover (17); a sleeve (21) is provided between the second bearings (22).

6. The piezoelectric stack driven rotating motor according to claim 1, characterized in that: The hinge lever element (25) is composed of two parallelogram rods, one of which is thicker than the other and has a slot in the middle, through which the other rod passes. Holes are drilled at the overlapping positions of the two rods, and tension springs (24) are connected to the two rods. The two rods realize lever movement with the first piezoelectric stack (12) through the tension springs (24).

7. A piezoelectric stack driven rotating motor according to claims 1-6, characterized in that: The housing (1), the base (3), the upper cover (17) and the end cover (19) are connected and fixed by means of screws.

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