Composite piezoelectric displacement actuator

Abstract

The invention provides a composite piezoelectric displacement actuator, which comprises an electromagnetic actuating mechanism, a piezoelectric driving mechanism, a piezoelectric driving mechanism, a first driving mechanism and a second driving mechanism, and is characterized in that the electromagnetic actuating mechanism is provided with a telescopic first output end; the piezoelectric actuating mechanism is provided with a telescopic second output end, and the piezoelectric actuating mechanism is connected with the first output end of the electromagnetic actuating mechanism; wherein the movement direction of the first output end is the same as the movement direction of the second output end, the electromagnetic actuating mechanism realizes ascending and descending displacement by pushing the fixed disc to rotate, the electromagnetic actuating mechanism is locked when encountering a scene with large thrust, and the piezoelectric actuating mechanism is in charge of output. Displacement control of various strokes is realized through the electromagnetic actuating mechanism and the piezoelectric actuating mechanism, so that the actuator can meet various working requirements.

Description

Technical Field

[0001] The invention relates to the field of displacement control, and in particular to a composite piezoelectric displacement actuator. Background Art

[0002] Although existing piezoelectric actuators can achieve displacement accuracy at the nanometer to micrometer level, their displacement stroke is relatively short, generally within 200 micrometers. Although electromagnetic actuators have a longer displacement stroke, up to thousands of micrometers, their displacement accuracy can only reach tens of micrometers at most. In some precision displacement scenarios, both a longer displacement stroke and nanometer-level displacement accuracy are required, and existing technologies cannot meet this demand. Summary of the invention

[0003] The object of the present invention is to provide a composite piezoelectric displacement actuator, while improving the stroke and displacement accuracy of the actuator.

[0004] In order to achieve the above-mentioned purpose, the present invention provides the following technical solution: a composite piezoelectric displacement actuator, comprising: an electromagnetic actuating mechanism, the electromagnetic actuating mechanism having a first output end capable of extension and retraction; a piezoelectric actuating mechanism, the piezoelectric actuating mechanism having a second output end capable of extension and retraction, and the piezoelectric actuating mechanism is connected to the first output end of the electromagnetic actuating mechanism; wherein the movement direction of the first output end is the same as the movement direction of the second output end.

[0005] Furthermore, the actuator also includes a switching mechanism; the first output end of the electromagnetic actuation mechanism is connected to the piezoelectric actuation mechanism through the switching mechanism.

[0006] Furthermore, the actuator also includes a shell, and the electromagnetic actuation mechanism, the switching mechanism and the piezoelectric actuation mechanism are all located in the shell.

[0007] Furthermore, the electromagnetic actuation mechanism includes a motor and a fixed disk, the output end of the motor is connected to the fixed disk, and when the motor is working, the output end of the motor can drive the fixed disk to rotate. Threads are provided on the side wall of the fixed disk and the inner wall of the shell, and the fixed disk can engage with the inner wall of the shell.

[0008] Furthermore, the piezoelectric actuation mechanism includes a piezoelectric ceramic rod, a buffer module and a drive head; the drive head includes a disc-shaped portion and a columnar portion, the columnar portion is connected to the disc-shaped portion, one end of the piezoelectric ceramic rod is connected to the adapter mechanism, and the other end of the piezoelectric ceramic rod is connected to the disc-shaped portion, the buffer mechanism is arranged between the disc-shaped portion and the inner wall of the shell, the shell is provided with an opening, and one end of the columnar portion extends out of the shell through the opening.

[0009] Furthermore, the buffer module includes a disc spring, one end of the disc spring is connected to the inner wall of the shell, and the other end of the disc spring is connected to the disc-shaped portion.

[0010] Furthermore, the piezoelectric actuation mechanism includes a limit platform, the limit platform is connected to the inner wall of the shell, and the piezoelectric ceramic rod passes through the limit platform and is connected to the driving head.

[0011] Furthermore, the shell includes a cylindrical shell, a top cover and a bottom plate, wherein the top cover and the bottom plate are respectively arranged at two ends of the cylindrical shell, wherein the opening is arranged on the top cover, and the motor is connected to the bottom plate.

[0012] Furthermore, the transfer mechanism comprises a transfer platform, one end of the transfer platform is provided with a pit, the fixed plate is provided with a convex ball, the convex ball is located in the pit, and the convex ball is in contact with the pit.

[0013] Furthermore, grating sensors are provided on both the piezoelectric ceramic rod and the inner wall of the shell, and the grating sensor on the piezoelectric ceramic rod is used in conjunction with the grating sensor on the inner wall of the shell.

[0014] From the analysis, it can be known that the present invention discloses a composite piezoelectric displacement actuator, in which the electromagnetic actuator mechanism realizes the upward and downward displacement by pushing the fixed plate to rotate. When encountering a scene with a large thrust, the electromagnetic actuator mechanism is locked and the piezoelectric actuator mechanism is responsible for the output. The displacement control of various strokes is realized by the electromagnetic actuator mechanism and the piezoelectric actuator mechanism, so that the actuator can meet various working requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0016] Figure 1 A schematic structural diagram of an embodiment of the present invention.

[0017] Explanation of the accompanying drawings: 1. Base plate; 2. Motor; 3. Fixed plate; 4. Transfer table; 5. Piezoelectric ceramic rod; 6. Limiting table; 7. Driving head; 8. Housing; 9. Disc spring; 10. Top cover. DETAILED DESCRIPTION

[0018] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention and does not limit the present invention. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as a part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desired that the present invention encompasses such modifications and variations within the scope of the appended claims and their equivalents.

[0019] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected", "connected" and "set" used in the present invention should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component; it can be a wired electrical connection, a radio connection, or a wireless communication signal connection. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0020] One or more examples of the present invention are shown in the accompanying drawings. The detailed description uses numbers and letter labels to refer to features in the drawings. Like or similar labels in the drawings and description have been used to refer to like or similar parts of the present invention. As used herein, the terms "first", "second", "third", and "fourth", etc. are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of individual components.

[0021] like Figure 1 As shown, according to an embodiment of the present invention, a composite piezoelectric displacement actuator is provided, comprising: an electromagnetic actuating mechanism, the electromagnetic actuating mechanism having a first output end capable of extension and retraction; a piezoelectric actuating mechanism, the piezoelectric actuating mechanism having a second output end capable of extension and retraction, and the piezoelectric actuating mechanism is connected to the first output end of the electromagnetic actuating mechanism; wherein the movement direction of the first output end is the same as the movement direction of the second output end.

[0022] The above-mentioned actuator also includes a switching mechanism; the first output end of the electromagnetic actuating mechanism is connected to the piezoelectric actuating mechanism through the switching mechanism.

[0023] The transfer mechanism comprises a transfer platform 4, one end of which is provided with a pit, and a convex ball is provided on the fixed plate 3, the convex ball is located in the pit, and the convex ball contacts the pit.

[0024] The convex ball and the concave pit form a hinge structure, and the hinge mechanism can make the axis of the piezoelectric ceramic rod 5 always coincide with the driving direction of the electromagnetic actuator mechanism, so even if the electromagnetic actuator mechanism is displaced, the force applied to the piezoelectric ceramic rod 5 can be vertical. Thereby, the axis of the piezoelectric ceramic rod 5 can be located on the same straight line as the axis of the fixed plate 3, so that the electromagnetic actuator mechanism can accurately control the displacement of the piezoelectric actuator mechanism.

[0025] The actuator further comprises a housing 8 , in which the electromagnetic actuation mechanism, the switching mechanism and the piezoelectric actuation mechanism are all located.

[0026] The housing 8 includes a cylindrical shell, a top cover 10 and a bottom plate 1 , wherein the top cover 10 and the bottom plate 1 are respectively arranged at two ends of the cylindrical shell, wherein an opening is arranged on the top cover 10 , and the motor 2 is connected to the bottom plate 1 .

[0027] The above-mentioned electromagnetic actuation mechanism includes a motor 2 and a fixed disk 3. The output end of the motor 2 is connected to the fixed disk 3. The output end of the motor 2 can drive the fixed disk 3 to rotate, but the output end of the motor 2 does not limit the movement of the fixed disk 3 in the vertical direction. It can be understood that the fixed disk 3 is similar to being sleeved on the output end of the motor 2, but the fixed disk 3 can prevent its rotation relative to the motor 2 through a limiting mechanism. When the motor 2 is working, the output end of the motor 2 can drive the fixed disk 3 to rotate. Threads are provided on the side walls of the fixed disk 3 and the inner wall of the shell 8, and the fixed disk 3 can engage with the inner wall of the shell 8.

[0028] The above-mentioned motor 2 is usually a brushless motor 2 , and a power supply line of the motor 2 passes through the housing 8 and is connected to the motor 2 , thereby supplying power to the motor 2 .

[0029] The fixing plate 3 is connected to the inner thread of the housing 8 . When the fixing plate 3 rotates, the fixing plate 3 moves up and down relative to the housing 8 under the guidance of the thread, thereby driving the piezoelectric actuator to move under the action of the transfer platform 4 .

[0030] The above-mentioned electromagnetic actuator is equipped with a locking mechanism, which is activated when encountering a scene with large thrust, and the piezoelectric actuator is responsible for the output.

[0031] The electromagnetic actuation mechanism described above is capable of operating while moving over a wide range, enabling the piezoelectric actuation mechanism to quickly move to the vicinity of a designated position.

[0032] The initial position of the fixed disk 3 can be adjusted in advance according to the use requirements. The fixed disk 3 is rotated to the required position, and the relative positions of the motor 2 and the piezoelectric ceramic rod 5 are adjusted at the same time to achieve the change of the output stroke of the actuator.

[0033] The piezoelectric actuator mechanism includes a piezoelectric ceramic rod 5, a buffer module and a drive head 7; the drive head 7 includes a disc-shaped portion and a columnar portion, the columnar portion is connected to the disc-shaped portion, one end of the piezoelectric ceramic rod 5 is connected to the adapter mechanism, and the other end of the piezoelectric ceramic rod 5 is connected to the disc-shaped portion, the buffer mechanism is arranged between the disc-shaped portion and the inner wall of the shell 8, and an opening is provided on the shell 8, and one end of the columnar portion extends out of the shell 8 through the opening.

[0034] The piezoelectric ceramic rod 5 is connected to an external power supply device via a power supply wire.

[0035] A capacitive sensor can be set on the object pushed by the above-mentioned driving head 7. The capacitive sensor can measure the displacement of the pushed object and provide feedback based on the measured displacement data to ensure the displacement accuracy of the piezoelectric actuator mechanism. The user can control the actuator based on the measured displacement data.

[0036] The axis of the piezoelectric ceramic rod 5, the axis of the drive head 7 and the axis of the housing 8 are all located on the same straight line. This arrangement enables the displacement of the piezoelectric ceramic rod 5 to be accurately reflected on the drive head 7 and makes the force on the drive head 7 more uniform.

[0037] The buffer module mentioned above includes a disc spring 9 , one end of which is connected to the inner wall of the housing 8 , and the other end of which is connected to the disc portion.

[0038] The disc spring 9 is in a suitable compression state, so that when the piezoelectric ceramic rod 5 is displaced to the maximum and minimum, the spring is within the range of elastic deformation, and the disc spring 9 always maintains the preload force applied to the piezoelectric ceramic rod 5 through the disc portion.

[0039] The piezoelectric actuation mechanism comprises a limit platform 6 , which is connected to the inner wall of the housing 8 , and the piezoelectric ceramic rod 5 passes through the limit platform 6 and is connected to the driving head 7 .

[0040] The above-mentioned limiting platform 6 limits the horizontal movement direction of the piezoelectric ceramic rod 5, so that the piezoelectric ceramic rod 5 can only move along the axis, making the output of the actuator more stable.

[0041] Grating sensors are provided on both the piezoelectric ceramic rod 5 and the inner wall of the housing 8 . The grating sensor on the piezoelectric ceramic rod 5 cooperates with the grating sensor on the inner wall of the housing 8 for use.

[0042] The above-mentioned grating sensors are the two ends of the grating ruler, one end of which is arranged on the piezoelectric ceramic rod 5, and the other end is arranged on the housing 8. The position of the piezoelectric actuator mechanism can be measured by the grating sensor, so that the user can control the working state of the actuator.

[0043] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: the electromagnetic actuator mechanism realizes the upward and downward displacement by pushing the fixed plate to rotate. When encountering a scenario with a large thrust, the electromagnetic actuator mechanism is locked and the piezoelectric actuator mechanism is responsible for the output. The displacement control of various strokes is realized by the electromagnetic actuator mechanism and the piezoelectric actuator mechanism, so that the actuator can meet various working requirements.

[0044] The above description is only a preferred embodiment of the present invention and is 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 in the protection scope of the present invention.

Claims

1. A composite piezoelectric displacement actuator, characterized in that: include: An electromagnetic actuation mechanism, wherein the electromagnetic actuation mechanism has a first output end capable of extension and contraction; A piezoelectric actuator mechanism, wherein the piezoelectric actuator mechanism has a second output end capable of extension and contraction, and the piezoelectric actuator mechanism is connected to the first output end of the electromagnetic actuator mechanism; The movement direction of the first output end is the same as the movement direction of the second output end.

2. A composite piezoelectric displacement actuator according to claim 1, characterized in that: The composite piezoelectric displacement actuator also includes a switching mechanism; The first output end of the electromagnetic actuation mechanism is connected to the piezoelectric actuation mechanism through the switching mechanism.

3. A composite piezoelectric displacement actuator according to claim 2, characterized in that: The composite piezoelectric displacement actuator further comprises a shell, and the electromagnetic actuation mechanism, the switching mechanism and the piezoelectric actuation mechanism are all located in the shell.

4. A composite piezoelectric displacement actuator according to claim 3, characterized in that: The electromagnetic actuation mechanism includes a motor and a fixed disk, the output end of the motor is connected to the fixed disk, and the output end of the motor can drive the fixed disk to rotate when the motor is working. Threads are provided on the side wall of the fixed disk and the inner wall of the shell, and the fixed disk can engage with the inner wall of the shell.

5. A composite piezoelectric displacement actuator according to claim 4, characterized in that: The piezoelectric actuation mechanism comprises a piezoelectric ceramic rod, a buffer module and a drive head; The driving head includes a disc-shaped portion and a columnar portion, the columnar portion is connected to the disc-shaped portion, one end of the piezoelectric ceramic rod is connected to the adapter mechanism, and the other end of the piezoelectric ceramic rod is connected to the disc-shaped portion, the buffer mechanism is arranged between the disc-shaped portion and the inner wall of the shell, the shell is provided with an opening, and one end of the columnar portion extends out of the shell through the opening.

6. A composite piezoelectric displacement actuator according to claim 5, characterized in that: The buffer module includes a disc spring, one end of which is connected to the inner wall of the housing, and the other end of which is connected to the disc portion.

7. The composite piezoelectric displacement actuator according to claim 5, characterized in that: The piezoelectric actuation mechanism comprises a limit platform, the limit platform is connected to the inner wall of the shell, and the piezoelectric ceramic rod passes through the limit platform and is connected to the driving head.

8. The composite piezoelectric displacement actuator according to claim 5, characterized in that: The housing comprises a cylindrical shell, a top cover and a bottom plate, wherein the top cover and the bottom plate are respectively arranged at two ends of the cylindrical shell, wherein the opening is arranged on the top cover, and the motor is connected to the bottom plate.

9. The composite piezoelectric displacement actuator according to claim 5, characterized in that: The transfer mechanism comprises a transfer platform, one end of which is provided with a pit, and the fixing plate is provided with a convex ball, which is located in the pit and contacts the pit.

10. The composite piezoelectric displacement actuator according to claim 5, characterized in that: The piezoelectric ceramic rod and the inner wall of the shell are both provided with grating sensors, and the grating sensor on the piezoelectric ceramic rod is used in conjunction with the grating sensor on the inner wall of the shell.

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