A method of controlling at least two interacting piezoelectric actuators
By applying a cyclic drive voltage signal with opposite phase to the piezoelectric actuator, the problem of inflexible control of piezoelectric actuators in the prior art is solved, and more flexible trajectory control and precise slider movement are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- PHYSIK INSTRUMENTE (PI) GMBH & CO KG
- Filing Date
- 2021-03-12
- Publication Date
- 2026-06-02
Smart Images
Figure CN115362625B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for controlling at least two interacting piezoelectric actuators to jointly displace an object attached thereto. This method is used, for example, to drive a dual-source inertial drive type motor, as described in EP3089348A1. Such a motor can drive a slider by utilizing a stick-slip effect. The two piezoelectric actuators are driven by corresponding cyclic drive voltage signals with stable frequencies. The cyclic drive voltage signals of the two piezoelectric actuators have multiple triangular waveforms and are mirrored to jointly move a friction element in contact with the slider to be driven. The tangential trajectory of the driven friction element is provided primarily by the interaction of the two piezoelectric actuators. In this inertial drive type motor, slider movement occurs because the friction element (contact point or area) of the motor moves slowly in one tangential direction, returns, and moves rapidly in the opposite direction. The result is a small step of the slider. This small movement accumulates as the sequence of movement of the friction element is repeated. As described, during these movements, the trajectory at the interface is tangential. Unfortunately, there are cases where the function of such a device is not optimal.
[0002] US6337532B1 relates to a fine stepping actuator. The corresponding electromechanical actuator arrangement includes multiple drive elements separated by a cutting element. Each drive element is divided into multiple discrete controllable phase segments. The individual electrode arrangements cause bending and / or expansion / contraction of the drive elements. The drive elements are divided into two groups, such that the drive elements within a group are jointly controlled. The two groups of drive elements typically have a 180-degree phase shift, but at least two groups of drive elements can be used. One embodiment of this design achieves fine stepping through appropriate electronic control. The gripping sequence of one group overlaps with the release sequence of the opposite group.
[0003] WO2005 / 122383A1 relates to a piezoelectric actuator, particularly for use in rechargeable battery-powered mobile devices. The piezoelectric actuator may include two independent, deflectable piezoelectric elements that can be connected together. A protrusion for moving an object is attached near the connection of the two piezoelectric elements. Applying a voltage between the respective voltage terminals of the piezoelectric elements changes the deflection degree of each piezoelectric element.
[0004] EP2495600A1 relates to an actuator for an optical deflector, the optical deflector comprising a mirror, a movable frame, and an internal piezoelectric actuator for moving the mirror relative to an X-axis. The internal piezoelectric actuator is fixed between the movable frame and a torsion bar. An external piezoelectric actuator is fixed between a support and the movable frame and is used to rock the mirror relative to a Y-axis. Summary of the Invention
[0005] Therefore, the object of the present invention is to provide a more flexible method for controlling at least two interacting piezoelectric actuators to jointly displace an object attached thereto.
[0006] This objective is achieved through a method that includes the following steps:
[0007] a. Step A: Apply a first cyclic drive voltage signal with a stable frequency to the first piezoelectric actuator;
[0008] b. Step B: Apply a second cyclic drive voltage signal with a stable frequency to the second piezoelectric actuator, wherein the frequencies of the first cyclic drive voltage signal and the second cyclic drive voltage signal are substantially the same, and wherein the frequencies of the first and second cyclic drive voltage signals are substantially out of phase (anti-cyclic), wherein the cyclic drive voltage signals in steps A and B are synchronized for at least a predetermined time period, such that at least one time phase is included in which the drive voltage signals of the first and second piezoelectric actuators both have a gradient of the same sign, decreasing or increasing the corresponding drive voltage signal.
[0009] The advantage of this method is that it allows not only tangential or tilted trajectories, but also other trajectories such as rectangles. This allows for greater flexibility in controlling two interacting piezoelectric actuators used for co-moving objects. This method also eliminates the need for, or can compensate for, specific orientations of the actuators relative to each other. For example, if this method is used to control a dual-source inertial drive motor using a rectangular trajectory at the slider-motor contact point, better controllability of the slider movement can be obtained. Until now, only mirrored triangular waveforms have been used. Using the method of this invention, one can deviate from a pure triangular waveform, and also from a strictly mirrored configuration of the two cyclic drive voltage signals. The terms "opposite phase" or "anti-cyclic" specifically mean that within the period (1 / frequency) of the drive voltage signals, the first drive voltage signal begins and ends at the reference voltage and crosses the reference voltage again. The second drive voltage signal also begins and ends at the reference voltage, crossing the reference voltage again during this period, but in the opposite direction. Therefore, the start and end points of the periods of the first and second drive voltage signals are preferably the same. This method allows for different trajectories to be provided by adapting the first cyclic drive voltage signal and the second drive voltage signal to each other in any possible way, regardless of whether the waveform is precisely mirrored or scaled differently, or has a fundamentally different shape.
[0010] Advantageous further development is the subject of the dependent claims.
[0011] The method may be advantageous when it includes (preferably within one cycle) the following time phases:
[0012] In the first time phase, the drive voltage signal from the first piezoelectric actuator increases from a reference voltage to a first upper intermediate voltage located between the reference voltage and a first upper peak voltage, or increases from the reference voltage to the first upper peak voltage; and the drive voltage signal from the second piezoelectric actuator decreases from the reference voltage to a second lower intermediate voltage located between the reference voltage and a second lower peak voltage, or decreases from the reference voltage to the second lower peak voltage.
[0013] In the second time phase, the drive voltage signal from the first piezoelectric actuator increases from a first upper intermediate voltage to a first upper peak voltage, or pauses at the first upper peak voltage, or decreases from the first upper peak voltage to a first upper intermediate voltage located between the first upper peak voltage and a reference voltage. Meanwhile, the drive voltage signal from the second piezoelectric actuator increases from a second lower peak voltage to a second lower intermediate voltage located between the second lower peak voltage and a reference voltage, or pauses at the second lower peak voltage, or decreases from the second lower intermediate voltage to the second lower peak voltage. Thus, in the second time phase, both the drive voltage signals from the first and second piezoelectric actuators have gradients of the same sign for decreasing or increasing the corresponding drive voltage signal, or one of these gradients is zero (e.g., paused) while the other is not zero, or both gradients are zero.
[0014] In the third time phase, the driving voltage signal of the first piezoelectric actuator decreases from the first upper peak voltage or the first upper intermediate voltage to the first lower intermediate voltage or the first lower peak voltage, and the driving voltage of the second piezoelectric actuator increases from the second lower intermediate voltage or the second lower peak voltage to the second upper intermediate voltage or the second upper peak voltage.
[0015] This means that in the first time phase, the length of the first piezoelectric actuator increases and the length of the second piezoelectric actuator decreases. It also means that in the third time phase, the length of the first piezoelectric actuator decreases and the length of the second piezoelectric actuator increases (or vice versa), while in the intermediate (second) time phase, neither of the two piezoelectric actuators performs an extension or contraction movement in the opposite direction to the other actuator. Then, in the second time phase, one actuator may remain stationary while the other remains stationary or moves in a particular direction, or both may move in the same direction. This behavior results in a trajectory completely different from those known in the art. The aforementioned time phases then follow in number, preferably one after another without any intermediate time phases. Preferably, in a certain time phase, the gradient of the drive voltage signal is stable, and preferably in subsequent time phases, the gradient of the drive voltage signal is different.
[0016] It can be useful when other additional time phases are included:
[0017] In the fourth time phase, the driving voltage signal of the first piezoelectric actuator increases from a first lower peak voltage to a first lower intermediate voltage located between the first lower peak voltage and a reference voltage, or pauses at the first lower peak voltage, or decreases from the first lower intermediate voltage to the first lower peak voltage; and the driving voltage of the second piezoelectric actuator increases from a second upper intermediate voltage to a second upper peak voltage, or pauses at the second upper peak voltage, or decreases from the second upper peak voltage to a second upper intermediate voltage located between the second upper peak voltage and a reference voltage. In the fourth time phase, the driving voltage signals of both the first and second piezoelectric actuators have gradients of the same sign for decreasing or increasing the corresponding driving voltage signals, or one of these gradients is zero and the other is not zero, or both gradients are zero, or the fourth time phase is omitted.
[0018] In the fifth stage, the driving voltage signal of the first piezoelectric actuator increases from the first lower intermediate voltage or the first lower peak voltage to the reference voltage, and the driving voltage of the second piezoelectric actuator decreases from the second upper intermediate voltage or the second upper peak voltage to the reference voltage.
[0019] Similar to the second time phase, in the fourth time phase, the two drive voltage signals do not decrease or increase in opposite directions. The fourth time phase can, for example, be used to compensate for the motion in the second time phase or to perform entirely different additional interactive motions. Alternatively, the fourth time phase can be omitted entirely, such that the fifth time phase follows the third time phase. Time phases then follow according to their sequence numbers. Preferably, the time phases follow each other immediately without any additional intermediate time phases. The only exception can be the fourth time phase, which can be omitted according to embodiments. Preferably, at a certain time phase, the gradient of the drive voltage signal is stable; preferably, in subsequent time phases, the gradient of the drive voltage signal is different.
[0020] In particular, if the piezoelectric actuator moves relatively slowly in one time phase and relatively quickly in the third time phase, according to one embodiment, it is advantageous that the gradient amount of increasing or decreasing the driving voltage signal of the first piezoelectric actuator in the second time phase is less than the gradient amount of decreasing the driving voltage signal of the first piezoelectric actuator in the third time phase, and / or the amount of increasing or decreasing the driving voltage signal of the second piezoelectric actuator in the second time phase is less than the gradient amount of increasing the driving voltage of the second piezoelectric actuator in the third phase. Especially in the third time phase, it is required that at least one actuator has a considerably fast movement, for example, to produce a beneficial stick-slip effect.
[0021] In another embodiment, the gradient amount of increasing the drive voltage signal of the first piezoelectric actuator in the first time phase may differ from the gradient amount of increasing, decreasing, or pausing the drive voltage signal of the first piezoelectric actuator in the second time phase, and / or the gradient amount of decreasing the drive voltage signal of the second piezoelectric actuator in the first time phase may differ from the gradient amount of increasing, decreasing, or pausing the drive voltage signal of the second piezoelectric actuator in the second time phase. This results in different movements of the actuator in these two phases to provide more beneficial trajectory control.
[0022] It is also possible to use a first piezoelectric actuator and a second piezoelectric actuator without generating a drive voltage signal, provided that a certain bias voltage has already been applied to the actuator. In this regard, according to another variant, it may be advantageous for the amount of the first upper peak voltage to differ from the amount of the first lower peak voltage and / or the amount of the second lower peak voltage. In this way, the movement of the corresponding actuator is asymmetrical relative to the starting position. This can, for example, prevent excessive force from being applied in a certain direction.
[0023] Preferably, the gradient amount of increasing, decreasing, or pausing the drive voltage signal of the first piezoelectric actuator in the fourth time phase may differ from the gradient amount of increasing or decreasing the drive voltage signal of the first piezoelectric actuator in the fifth and / or third time phases, and / or the gradient amount of increasing, decreasing, or pausing the drive voltage signal of the second piezoelectric actuator in the fourth time phase may differ from the gradient amount of increasing or decreasing the drive voltage signal of the second piezoelectric actuator in the fifth and / or third time phases. Similar to the second time phase, the expansion or contraction of the corresponding actuator is performed at different speeds in each time phase, thereby allowing for better trajectory control, which may preferably be adapted to a specific application.
[0024] The drive voltage signal of the piezoelectric actuator is itself generated by a combination of corresponding excitation voltages at the first and second terminals, meaning that the drive voltage signal itself is the result of a combination of two excitation voltage curves. According to a preferred embodiment, the drive voltage signals of the first and second piezoelectric actuators are generated by a cyclic first excitation voltage applied to the first terminal and a cyclic second excitation voltage applied to the second terminal, wherein the first terminal is preferably a positive terminal and the second terminal is preferably a negative terminal, and the amount of the upper peak voltage of the cyclic first excitation voltage is higher than the amount of the lower peak voltage of the cyclic first excitation voltage, and the amount of the upper peak voltage of the cyclic second excitation voltage is lower than the amount of either the upper or lower peak voltage of the cyclic first excitation voltage. The excitation voltages preferably have the same frequency. In known applications, the excitation voltage is applied in a triangular waveform, whereby the waveform of the excitation voltage at the second terminal has been mirrored with the waveform of the excitation voltage at the first terminal. This results in a triangular waveform where the upper and lower peak voltages are doubled. In contrast, in this invention, while the first and second excitation voltages preferably have the same frequency and are also preferably slightly triangular in form, it is also feasible that they have the same profile on another scale. Preferably, they are two isolated and distinct triangular waveforms. Depending on the amplitude and phase difference of these two waveforms, the actuator is applied not only with a strictly sawtooth triangular waveform but also with other types of waveforms.
[0025] For some applications, it can be advantageous when the peak voltages of the first and second cyclic excitation voltages are applied synchronously, preferably simultaneously. Particularly advantageous is when one of the excitation voltages has only a single sign (positive or negative), while the other has both positive and negative signs within one cycle.
[0026] It can be conveniently demonstrated that, in one variation, the object typically displaced and attached to by both the first and second piezoelectric actuators is at least one friction element of an inertial drive motor, whereby the at least one friction element is configured to frictionally contact the element to be driven, at least in the non-operating state of the first and second piezoelectric actuators. This inertial drive motor moves the slider, for example, by contacting at least one friction element. This movement of the slider can be improved by applying trajectory control according to the invention to adapt it to a specific application. More than one motor can jointly drive the slider.
[0027] Preferably, the inertial drive motor may include an elastic frame, at least one friction element disposed on the elastic frame, and first and second piezoelectric actuators configured to cause deformation of the elastic frame through interaction using corresponding drive voltage signals. In this design, piezoelectric actuators positioned side-by-side and having parallel expansion and contraction axes can be used. This simplifies the construction of such an inertial drive motor.
[0028] According to another embodiment, the first and second piezoelectric actuators can be configured to displace at least one friction element in frictional contact with the driven element in a forward direction during a first time phase, retract at least one friction element from the driven element during a second time phase, and displace at least one friction element in the retracted state in a rearward direction during a third time phase. This method results in reduced friction between the friction element and the driven element, such that the movement in the rearward direction during the third time phase can be achieved with reduced frictional contact or no frictional contact with the driven element. For example, a triangular trajectory can be used. This leads to better controllability of the movement of the driven element (e.g., a slider).
[0029] According to another embodiment, the elastic frame can be attached to a portion of a lever structure including a post on which at least one friction element is disposed, such that the deformation of the elastic frame caused by the interaction of the first and second piezoelectric actuators is amplified by the lever structure and transferred to the at least one friction element. Therefore, using such a structure can increase the movement steps of the friction element, or can improve the positioning of such an inertial drive motor.
[0030] In another embodiment, it is preferable to provide at least three or preferably four piezoelectric actuators configured to co-displace and attach to at least one friction element, whereby the piezoelectric actuators are controlled by their corresponding drive voltage signals to displace at least one of the friction elements in the x and z directions, and to retract at least one friction element from the element to be driven in the y direction. The x and z directions define a plane parallel to the movement of the element to be driven relative to each other using two or more actuators of a particular arrangement, which can move the element to be driven not only back and forth, but also in intersecting and combined directions. It is still possible to affect the frictional contact of the friction element to be driven by involving movement in the y direction.
[0031] Alternatively, the object typically displaced and attached to by the first and second piezoelectric actuators is the central mass block of the piezoelectric-hydraulic actuator. Such a piezoelectric-hydraulic actuator uses two opposing one-way valves for fluid transfer from one chamber to another. Synchronous movement of the two actuators in the same direction will open only one valve, thus fluid transfer will be in only one direction. With the method of the present invention, corresponding control is feasible.
[0032] The present invention also relates to a component comprising an assembly of two interacting first and second piezoelectric actuators, a displaceable object attached to the first and second piezoelectric actuators, and means for applying and controlling cyclic drive voltage signals for controlling the interaction of the first and second piezoelectric actuators to displace the object, wherein the means for applying and controlling are configured to perform the method according to any one of the preceding claims. Such means allows for adapted trajectory control of a dual-source driven object.
[0033] In one embodiment of this component, a drive electronics device with two signal sources is provided, each signal source having an active terminal and a passive terminal. Only the active terminals are electrically connected to the positive or negative terminals (12a, 12b) of the piezoelectric actuators, and the other of the positive or negative terminals (12a, 12b) of the piezoelectric actuators is electrically connected to each other, causing them to float. The passive terminals of both signal sources are grounded. As a result, the two piezoelectric actuators are electrically connected in series. This configuration simplifies the drive electronics device because only two wires travel from the signal sources to the respective piezoelectric actuators. Attached Figure Description
[0034] In the following description and illustration, several embodiments of the invention are shown in conjunction with the accompanying drawings, in which:
[0035] Figure 1 This is a perspective view of the first embodiment of an inertial drive type electric motor.
[0036] Figure 2 yes Figure 1 The front view of the electric motor is shown, along with a possible rectangular trajectory.
[0037] Figure 3 It is similar to Figure 1 A schematic diagram of a dual-source inertial drive motor is shown, illustrating its contact with the slider.
[0038] Figure 4 This is a schematic side view of a piezoelectric actuator.
[0039] Figure 5a This is a schematic side view of a second embodiment of the piezoelectric actuator.
[0040] Figure 5b From Figure 5aA view of the piezoelectric actuator from below;
[0041] Figure 6 This is a perspective view of a partially cut-off piezoelectric multilayer actuator;
[0042] Figure 7 This is a simplified schematic diagram of the driving steps in an inertial drive type electric motor.
[0043] Figure 8 yes Figure 7 A schematic diagram of the drive voltage signals of the two actuators in the corresponding steps;
[0044] Figure 9a This is a diagram showing the first and second excitation voltages of the first piezoelectric actuator in an inertial drive motor;
[0045] Figure 9b This is a diagram showing the driving voltage signal obtained from the first piezoelectric actuator;
[0046] Figure 10a This is a diagram showing the first and second excitation voltages of the second piezoelectric actuator.
[0047] Figure 10b This is a diagram showing the drive voltage signal obtained from the second piezoelectric actuator.
[0048] Figure 11 This is a diagram showing the interchangeable first and second drive voltage signals;
[0049] Figure 12 This is a diagram illustrating further replacements of the first and second drive voltage signals.
[0050] Figure 13 This is a diagram illustrating further replacements of the first and second drive voltage signals.
[0051] Figure 14 This is an alternative diagram of the first and second drive voltage signals;
[0052] Figure 15a This is a schematic side view of an alternative connection between two piezoelectric actuators.
[0053] Figure 15b This is a schematic side view of an alternative connection, with only the positive terminal 12a connected to the drive electronics, and the other wiring of the signal source terminated or grounded in the drive electronics.
[0054] Figure 16a This is a 3D diagram of an alternative configuration for an inertial drive type electric motor.
[0055] Figure 16b yes Figure 16a A three-dimensional view of a square cross-section of an inertial drive type electric motor.
[0056] Figure 17a This is a perspective view of an alternative embodiment of an inertial drive type electric motor.
[0057] Figure 17b yes Figure 17a A three-dimensional view of a square cross-section of an inertial drive type electric motor.
[0058] Figure 18a This is a perspective view of an alternative embodiment of an inertial drive type electric motor.
[0059] Figure 18b yes Figure 18a A three-dimensional view of a square cross-section of an inertial drive type electric motor.
[0060] Figure 19a It is a 3D diagram of a piezoelectric hydraulic actuator, and
[0061] Figure 19b yes Figure 19a A perspective view of the square portion of a piezoelectric hydraulic actuator. Detailed Implementation
[0062] exist Figure 1 , Figure 2 and Figure 3 The image shows a first embodiment of an inertial drive type motor 1. This inertial drive type motor 1 is used to move a slider 2 by a small movement at the motor-slider contact point (see...). Figure 3 The inertial drive type motor 1 has an elastic frame 3, which includes an elastic base element 4 and two or more frame-like leaf springs 5 attached to either side of the base element 4, such that only one longitudinal side of each spring 5 contacts the base element 4. The base element 4 provides a recess 6, which is bridged by one longitudinal side of the upper frame-like leaf spring 5. Two piezoelectric actuators 7 and 8 are sandwiched in a slightly offset configuration between the upper leaf spring 5 and the bottom of the recess 6 of the base element 4. Just between the two piezoelectric actuators 7 and 8, a friction element (tip) 9 is attached to one side of the upper leaf spring 5 such that it protrudes upward and contacts the underside of the slider 2 in an offset configuration during use. The two piezoelectric actuators 7 and 8, placed side by side, have vertical actuation directions A1 and A2 perpendicular to the extension of the leaf springs 5. These leaf springs 5 are attached to the base element 4 by means of screws 10.
[0063] By driving piezoelectric actuators 7 and 8 in a specific manner, friction element 9 (or connector) performs forward and backward movement to move slider 2. This is possible due to the stick-slip effect using different speeds in the forward and backward movements.
[0064] exist Figures 1 to 3 In the illustrated embodiment, multilayer piezoelectric actuators 7 and 8 are used. These actuators... Figure 6The cross-sectional portion shows the internal electrode connectivity from the internal electrodes 11a and 11b to the external electrodes or terminals 12a and 12b.
[0065] Alternatively, a single-layer piezoelectric actuator with a positive terminal 12a and a negative terminal 12b can be used. Figure 5a and Figure 5b Alternative configurations of piezoelectric actuators 7 and 8 with multilayer configurations and their corresponding positive and negative terminals 12a and 12b are shown.
[0066] Combination Figure 7 To describe in more detail Figures 1 to 3 The operation of the inertial drive type motor 1 shown.
[0067] Figure 7 In the following six steps, the movement of the friction element 9 of the inertial drive motor 1 is shown, which is performed by the inertial drive motor 1 during one excitation cycle of the first piezoelectric actuator 7 and the second piezoelectric actuator 8. The forward movement of the friction element 9 occurs due to the synchronous expansion and contraction of the first piezoelectric actuator 7 and the second piezoelectric actuator 8, which is caused by their corresponding synchronous cyclic drive voltage signals 13 and 14 (see...). Figure 8 ).
[0068] In step 0, the friction element 9 is in its natural (untilted) position. This corresponds to... Figure 8 In step 0, both the first driving voltage signal 13 and the second driving voltage signal 14 have a value of 0 volts, i.e., reference voltages 15a and 15b in this configuration. Actuators 7 and 8 both have their intermediate positions, meaning they neither expand nor contract, so that the elastic frame 3 does not deform. In step 1, the friction element 9 tilts slowly in the forward direction due to the bending of the elastic frame 3. The slider 2 also moves together with the friction end 9. The movement between step 0 and step 1 is completed by a slow increase of the first driving voltage signal 13 from the reference voltage 15a to the first upper peak voltage 16a. The increase is linear and has a positive gradient because the first upper peak voltage is also positive. This gradient is the quotient (rate) of the voltage change over a specific time period.
[0069] The voltage changes that occur during the two subsequent steps are drawn with solid lines, while the remainder of the driving voltage signal in that cycle is drawn with dashed lines.
[0070] Simultaneously (in the first time phase), the second driving voltage signal 14 decreases from the reference voltage 15b to the second lower intermediate voltage 17b. The voltage change is linear, and the corresponding gradient is negative. In this embodiment, the magnitudes of the upper peak voltage 16a and the second lower intermediate voltage 17b are the same.
[0071] In step 2, the friction element 9 has already moved rapidly back in the normal direction, so the friction element is retracted and disengaged from the slider 2 (in other embodiments, only the friction or bias between the friction element 9 and the slider 2 may be reduced). This movement of the friction element 9 is due to the first driving voltage signal 13 decreasing from the first upper peak voltage 16a to the first upper intermediate voltage 18a in the second time period, during which the gradient is negative. In the same second time period, the second driving voltage signal 14 decreases from the second lower intermediate voltage 17b to the second lower peak voltage 19b. The gradient of the second driving voltage signal 14 in the second time period is also negative (having the same sign as the gradient of the first driving voltage signal 13). The two gradients in the second time period are the same, and this amount is greater than the gradient amount in the first time period.
[0072] In the third step, friction element 9 has undergone a fairly rapid reverse (backward) movement without any interference from slider 2. Contrary to known driving concepts for such friction elements, this avoids frictional nonlinearities that could interfere with slider movement. The rapid reverse movement is due to the rapid changes in the first and second driving voltage signals 13 and 14 during the third time phase. During the third time phase, the first driving voltage signal 13 decreases from a first upper intermediate voltage 18a to a first lower peak voltage 19a. The gradient of the first driving voltage signal 13 in the third time phase is negative, and its magnitude is greater than the gradient magnitudes in the first and second time phases. Correspondingly, the second driving voltage signal 14 increases fairly rapidly from a second lower peak voltage 19b to a second upper intermediate voltage 18b during the third time phase. The gradient has a positive sign, and its magnitude is greater than the gradient magnitudes in the first and second time phases.
[0073] In the fourth step, the friction element 9 moves forward in the vertical direction and contacts the slider 2 again, causing it to engage with the slider 2 once more. This movement occurs in the fourth time phase by the waveforms of the first driving voltage signal 13 and the second driving voltage signal 14. In the fourth time phase, the first driving voltage signal 13 increases from a first lower peak voltage 19a to a first lower intermediate voltage 17a. The corresponding gradient is positive and the amount is the same as the gradient amount in the second time phase. In the fourth time phase, the corresponding second driving voltage signal 14 increases from a second upper intermediate voltage 18b to a second upper peak voltage 16b. The sign of the gradient in the fourth time phase is also positive for the second driving voltage signal 14 (having the same sign as the gradient of the first driving voltage signal 13).
[0074] In the fifth step, the friction element 9 has returned to its natural position by moving forward. This is achieved by the first driving voltage signal 13, which increases from the first lower intermediate voltage 17a to the reference voltage 15a. The gradient corresponding to the fifth time stage is positive and its magnitude is lower than that in the third and fourth time stages. In the fifth time stage, the corresponding second driving voltage signal 14 decreases from the second upper peak voltage 16b to the reference voltage 15b. The gradient is negative and its magnitude is less than that in the third and fourth time stages.
[0075] It should be noted that, in Figure 8 The diagram illustrates one cycle (1 / frequency) of the first driving voltage signal 13 and a corresponding cycle (1 / frequency) of the second driving voltage signal 14. The first and second driving voltage signals 13 and 14 are thus synchronized and substantially out of phase or in reverse cycle. Each of these signals reaches its corresponding reference voltage 15a or 15b three times, i.e., at the beginning of the cycle, at the end of the cycle, and sometime in the middle. It should be noted that in the first, third, and fifth time phases, the gradients of the first driving voltage signal 13 and the second driving voltage signal 14 have opposite signs, while in the second and fourth time phases, the gradients of the first driving voltage signal 13 and the second driving voltage signal 14 have the same sign. Whenever the driving voltage signal 14 is positive (above the reference voltage), the corresponding piezoelectric actuator 7 or 8 is in an expanded state; whenever the corresponding driving voltage signal 13 or 14 is negative, the corresponding piezoelectric actuator 7 or 8 is in a contracted state. These gradients remain the same within a time phase.
[0076] The interaction between the first piezoelectric actuator 7 and the second piezoelectric actuator 8 causes the desired deformation of the elastic frame 3, thus resulting in corresponding movement of the friction element 9 in the forward and rearward directions, and a slight movement in the direction perpendicular to it, causing the friction element 9 to separate from or engage with the slider 2. This is achieved by using drive voltage signals 13 and 14, such as... Figure 8 As shown, not only are tangential or inclined trajectories of the friction element 9 feasible, but rectangular motion of the friction element 9 is also feasible, as shown in the figure. Figure 2 It is depicted above the friction element 9. (As shown in...) Figure 7 As can be seen in particular, the slider 2 moves forward in two steps during each cycle of the first driving voltage signal 13 and the second driving voltage signal 14. It should be noted that a larger motor structure can be produced by using multiple inertial drive type motors 1 to jointly drive the slider 2.
[0077] Figure 9a and Figure 9b as well as Figure 10a and 10b Explain how to apply the first drive voltage signal 13 and the second drive voltage signal 14 at the corresponding first piezoelectric actuator 7 and second piezoelectric actuator 8. Figure 9a The solid line shows the triangular waveform of the cyclic first excitation voltage 20 applied at the first (positive) terminal 12a of the first piezoelectric actuator 7, and the dashed line shows the cyclic second excitation voltage 21 applied at the second (negative) terminal 12b of the first piezoelectric actuator 7. This cyclic second excitation voltage is also a sawtooth waveform, but only has values between zero and the positive peak voltage, which is 10V in the current case. The cyclic first excitation voltage 20 has a positive peak voltage (30V) higher than the lower peak voltage (-20V). The peak voltage of the cyclic second excitation voltage 21 occurs simultaneously with the upper peak voltage of the cyclic first excitation voltage 20. The cyclic first excitation voltage 20 at the first terminal 20a and the cyclic second excitation voltage 21 at the second terminal 12b generate a first drive voltage signal 13, as shown below. Figure 9b As shown. If as Figure 9a The waveform shown is applied to the positive terminal 12a and the negative terminal 12b, and the resulting drive voltage signal of the first piezoelectric actuator 7 is V1 = (V1+) - (V1-).
[0078] Similarly, Figure 10a and Figure 10b The corresponding cyclic first excitation voltage 22 and cyclic second excitation voltage 23 for the second piezoelectric actuator 8, and the corresponding second drive voltage signal 14 are shown. Figure 10b Furthermore, here, the waveform applied to the positive terminal 12a (shown as a solid line (V2+)) and the waveform applied to the negative terminal 12b (shown as a dashed line (V2-)) are generated. Figure 10b The second drive voltage signal 14 (V2) is shown in the figure.
[0079] As a result, the potentials at the positive terminal 12a and negative terminal 12b of the piezoelectric actuator 7 or 8 in the inertial drive motor 1 are two isolated and distinct triangular waveforms. Depending on the amplitude and phase difference of these two waveforms, the actuator 7 or 8 can be set not only to a sawtooth triangular waveform but also to other types of waveforms. Consequently, the aforementioned trajectory, such as the rectangular trajectory at the slider-motor contact point, can be generated, which can lead to better controllability of the slider movement.
[0080] By actuating the inertial drive type motor 1 of the first and second piezoelectric actuators 7 and 8 using the described first and second drive voltage signals 13 and 14, precise movement of the slider 2 is provided by avoiding interference with the movement due to frictional nonlinearity. Particularly in the third time phase, when the friction element 9 moves backward quite rapidly, the described method avoids friction caused by the retraction of the friction element 9 in the second time phase during this backward movement. It is also possible to reduce the friction between the friction element 9 and the slider 2 only in the second time phase in order to avoid frictional nonlinearity to a certain extent (e.g., the friction is reduced by more than 25%, preferably more than 50%, compared to the neutral position of the friction element 9).
[0081] When driving the inertial drive type motor 1, it is important that the voltage on the piezoelectric actuators 7 and 8 begins to rise or fall from, for example, 0V (reference voltage) to its maximum or minimum value, and returns to, for example, 0V (reference voltage) at the end of each cycle. This is to keep the friction element in its natural position at the beginning and end of a cycle. The rise and fall times of the slip phase with this drive waveform are preferably in the middle of the cycle. This waveform is the most general of the drive waveforms. The amplitude at the beginning and end of the cycle is typically 0V (reference voltage). Most of the time, the amplitudes of the intermediate voltage and the corresponding peak voltage can be set independently to different values, but they can often also be equal.
[0082] In the following text, refer to Figures 11 to 14 These figures illustrate the first drive voltage signal 13 and the corresponding second drive voltage signal 14 for different applications. These waveforms can also be used in other piezoelectric drive devices, where two piezoelectric actuators are used accordingly. To create a combination with the above... Figure 8 The trajectories described are different.
[0083] Furthermore, a single-cycle waveform is divided into five time phases. Figure 11 In the second and fourth time stages, the rate of change (gradient) of the amplitude has the same sign. Here, the sign is positive (+) in both the second and fourth time stages. In the first, third, and fifth time stages, the rate of change (gradient) of the amplitude has different signs, and the rate of change is different, which means that the corresponding gradient amount in each of these time stages is different.
[0084] Turning Figure 12The diagram illustrates the waveforms of a first driving voltage signal 13 and a second driving voltage signal 14 according to another embodiment. In the second and fourth time phases, the gradients of the first driving voltage signal 13 and the second driving voltage signal 14 have the same sign. In the second time phase, both gradients have negative signs, while in the fourth time phase, both gradients have positive signs. In the first, third, and fifth time phases, the gradients of the first and second driving voltage signals 13 and 14 are always opposite. In the first time phase, the gradient amounts are the same, such that the first upper peak voltage 16a has the same amount as the second lower intermediate voltage 17b. The second lower peak voltage 19b is the same as the first lower peak voltage 19a. The first upper intermediate voltage 18a is the same as the second upper intermediate voltage 18b.
[0085] Figure 13 Another variation is illustrated. The first driving voltage signal 13 and the second driving voltage signal 14 are mirror images of each other at the reference voltage line. In the second time phase, the first voltage signal 13 pauses at the first upper peak voltage 16a, and the second driving voltage signal 14 pauses at the second lower peak voltage 19b. In the fourth time phase, the second driving voltage signal 14 pauses at the second upper peak voltage 16b, and the first driving voltage signal 13 pauses at the first lower peak voltage 19a. Therefore, the gradients of the two driving voltage signals 13 and 14 are zero. In the first, third, and fifth time phases, the signs of the gradients of the first driving voltage signal 13 and the second driving voltage signal 14 are always opposite, but the gradient magnitudes are the same in each time phase.
[0086] exist Figure 14 Another embodiment of driving voltage signals 13 and 14 is disclosed. Again, in the second and fourth time phases, the gradients of these two driving voltage signals 13 and 14 are zero. In the remaining time phases, the signs of the two gradients of the first and second driving voltage signals 13 and 14 are opposite, respectively. Furthermore, in the first, third, and fifth time phases, the rates of change (gradient amounts) in the waveforms of the first driving voltage signal 13 and the second driving voltage signal 14 are different.
[0087] Figures 11 to 14 Combination Figure 8 The diagram illustrates numerous variations in the waveforms of the first drive voltage signal 13 and the second drive voltage signal 14. The gradients at each time stage can be different; at least in one time stage, the signs of the gradients are the same, or one of these gradients is zero while the other is not zero, or both gradients are zero. Reasonable alterations and variations can be used in all other time stages. It is also possible to extend or compress these time stages, or even omit one of them. In particular, a fourth time stage may, for example, be... Figure 13 and Figure 14In one of the illustrated embodiments, this is omitted so that the corresponding drive voltage signal 13 or 14 does not pause at the corresponding peak voltage 16a, 16b, 19a or 19b. According to... Figure 9a , 9b The principles explained in 10a and 10b involve modifying the drive voltage signal as described above and all other modifications using corresponding cyclic first and second excitation voltages. Therefore, the trajectory of the friction element 9 can be adapted to any possible trajectory through the interaction of two or more piezoelectric actuators, which can be generated by modulation of waveforms as described herein.
[0088] Typically, the first piezoelectric actuator 7 and the second piezoelectric actuator 8 are independently actuated by corresponding first excitation voltage 13 and second excitation voltage 14. Figure 15a The diagram shows a configuration where only two wires pass through the drive electronics to provide corresponding drive voltage signals 13 and 14 to the first piezoelectric actuator 7 and the second piezoelectric actuator 8, respectively. The negative terminals 12b are electrically connected to each other and are floating. Figure 15b As shown, the positive terminal 12a is connected to the driving electronics, such as... Figure 15b As shown. Since the negative terminal 12b is not connected to the driving electronics but is floating, both piezoelectric actuators 7 and 8 are driven as if there were only one actuator. There are two main advantages to this driving configuration:
[0089] First, the driver will see a small capacitor, while the two piezoelectric actuators 7 and 8 are connected in series. Second, another advantage is that only two wires are connected to the control electronics, as is the case with only one piezoelectric actuator in an inertial drive type motor 1. In short, the negative terminals 12b of the two piezoelectric actuators 7 and 8 are electrically short-circuited to each other and not connected anywhere. This configuration can be used with... Figure 11 , Figure 12 , Figure 13 and Figure 14 Either of the two previously described waveforms 13 and 14 shown are used together. However, the potential difference between the two waveforms will be shared equally by the two actuators. The waveforms applied to the positive terminals 12a of the two piezoelectric actuators 7 and 8 are identical, but mirror images, so the gradients of the signals can always be equal, but with opposite signs or zero.
[0090] In the following text, Figure 16a and Figure 16bAnother embodiment of the inertial drive type electric motor 1 is shown. In the illustrated embodiment, a lever structure is used, which includes a column 24 on which a friction element 9 is positioned. The column 24 is located between two piezoelectric actuators 7 and 8, and the elastic frame 3 of the inertial drive type electric motor 1 includes two base elements 4.1 and 4.2 (end mass blocks). The piezoelectric actuators 7 and 8 are thus clamped between the arms 25 of the base elements 4.1 and 4.2 and the lower leaf spring 5. The upper spring 5 has a U-shaped or V-shaped intermediate section 26 on which the column 24 is positioned. The lower part of the intermediate section 26 is in almost contact with the lower leaf spring 5, with a small gap between them. Screws 10 attach the upper spring 5 to the base elements 4.1 and 4.2, the lower spring 5 to the base elements 4.1 and 4.2, and the column 24 and the intermediate section 26 to the lower spring 5. When the two piezoelectric actuators 7 and 8 are electrically excited at 180° out of phase, their motion in the length (or thickness) direction is antisymmetric. These antisymmetric motions are transmitted as wobbling motions to the column 24 and the friction element 9. The trajectory provided by the friction element 9 can be modified by using the drive voltage signal as described above.
[0091] Even when the component is combined with screw 10, other combination methods can be used, such as welding or epoxy bonding. A separate friction element is not necessarily required. The post 24 itself can provide the corresponding function. For example, a ceramic material structure attached to the end of the post 24 can also be used as a friction element.
[0092] Combination Figure 17a and 17b The above-mentioned Figure 16a and 16b An alternative structure to the similar inertial drive type motor 1. In this configuration, the base elements 4.1, 4.2, the lower spring 5, and the column 24 are integrally formed. Two piezoelectric actuators 7 and 8 are clamped between the upper and lower parts of the elastic frame 3, respectively. Two screws 10 are used to remove actuator tolerances and hold them between the portions of the elastic frame 3. When the piezoelectric actuators 7 and 8 expand and contract simultaneously in the longitudinal direction, these deformations are converted into angular motion of the lever structure (specifically the column 24) due to the base elements 4.1 and 4.2 (end mass blocks). The deformation of the actuators 7 and 8 occurs at the lower end of the column 24 between the two piezoelectric actuators 7 and 8. This lever structure amplifies the deformation caused by the actuators 7 and 8 at the end where the friction tip 9 is located. The corresponding hinge point is at the lower end of the column 24. The trajectory provided by the friction element 9 can be modified by using the drive voltage signal as described above.
[0093] Now for reference Figure 18a and Figure 18b Another embodiment is shown.
[0094] Used with Figure 16a and Figure 16b A similar structure is used in the embodiment. However, the central column 24 is combined with four piezoelectric actuators 7.1, 7.2, 8.1, and 8.2. The elastic frame 3 is in the form of a wheel, with four spokes and corresponding four arms 5. The upper spring 5 and the lower spring 5 are connected to the spokes of the base element 4. The upper spring 5 also has four spokes, which together form a recess in the middle, in which the column 24 is located. The lower spring 5 also has four spokes. The spokes of the upper spring 5 and the lower spring 5 are respectively connected to the corresponding spokes of the base element 4 by screws. By appropriately exciting the piezoelectric actuators 7.1, 7.2, 8.1, and 8.2 in phase or out of phase, movement of the column 24 in different directions can be obtained. The friction elements 9 are moved by the column 24 (lever structure). Thus, an inertial drive type motor 1 is generated, which can move the corresponding slider 2 in two degrees of freedom of motion. The corresponding drive voltage signals are synchronized respectively to obtain such movement. The driving voltage signal that can generate three-dimensional motion of friction element 9, as described above, can be used.
[0095] Figure 18a and Figure 18b The structure shown can also be replaced by an elastic frame 3, which is composed of and Figure 17a and Figure 17b The structures shown in the embodiments are made from a single piece, which means that the two springs 5, the base element 4, and the column 24 are made from a single piece.
[0096] about Figure 19a and Figure 19b Another embodiment is shown. Figure 19a and Figure 19bThis invention relates to a piezoelectric-hydraulic actuator 30 for precise movement of a central mass block 31. The piezoelectric-hydraulic actuator 30 includes: a rigid frame 32; a first piezoelectric actuator 7; and a second piezoelectric actuator 8 on the opposite side; a first connecting element 33 attached to the first actuator 7; and a second connecting element 34 attached to the second piezoelectric actuator 8; a first bellows 35 positioned between the first connecting element 33 and the central mass block 31; and a second bellows 36 positioned between the second connecting element 34 and the central mass block 31. The central mass block 31 includes two parallel fluid flow channels 37 and 38, which are respectively closed at one end by check valves 39 and 40. The first bellows 35 and the second bellows 36 are filled with fluid and act as reservoirs. The fluid flow channels 37 and 38, combined with the corresponding check valves 39 and 40, are formed as opposing fluid diodes, serving as hydraulic chargers or accumulators. Two piezoelectric actuators 7 and 8 can simultaneously apply pressure to bellows 35 and 36, causing a pressure difference within the bellows to create fluid flow from one bellows to the other. This results in a change in the length of both bellows, one expanding while the other contracts. This, in turn, produces movement of the central mass block 31 guided by a linear bearing within frame 32. The hysteresis of both piezoelectric actuators 7 and 8 is reduced by two mirrored sawtooth signals. Furthermore, during fluid transfer, the response time is faster, with the pressure on one side increasing due to the expansion of the corresponding piezoelectric actuator 7 or 8, and the pressure on the other side decreasing due to the contraction of the corresponding piezoelectric actuator 7 or 8. These two synchronized movements will cause only one check valve 39 or 40 to open, thus fluid transfer will be in only one direction. As described above, modifications to the first and second drive voltage signals 13 and 14 are feasible to produce the specific behavior of the piezoelectric-hydraulic actuator 30 as shown here.
[0097] List of reference numerals in the attached figures
[0098] 1. Inertial drive type electric motor
[0099] 2 sliders
[0100] 3 Flexible Frame
[0101] 4.1.4.2 Base Components
[0102] 5 leaf springs
[0103] 6 recesses
[0104] 7.1, 7.2 First piezoelectric actuator
[0105] 8.1, 8.2 Second piezoelectric actuator
[0106] 9 friction elements
[0107] 10 screws
[0108] Internal electrodes (terminals) of 11a and 11b
[0109] 12a, 12b External Electrodes (Terminals)
[0110] 13 First cycle drive voltage signal
[0111] 14 Second cycle drive voltage signal
[0112] 15a, 15b reference voltage
[0113] 16a First Peak Voltage
[0114] 16b Second Peak Voltage
[0115] 17a First Intermediate Voltage
[0116] 17b Second Intermediate Voltage
[0117] 18a First Intermediate Voltage
[0118] 18b Second Intermediate Voltage
[0119] 19a First Lower Peak Voltage
[0120] 19b Second Lower Peak Voltage
[0121] 20-cycle first excitation voltage
[0122] 21-cycle second excitation voltage
[0123] 22-cycle first excitation voltage
[0124] 23rd cycle, second excitation voltage
[0125] 24 columns
[0126] 25 arms
[0127] 26 intermediate sections
[0128] 30 piezoelectric hydraulic actuator
[0129] 31 center mass block
[0130] 32-frame
[0131] 33 Connecting elements
[0132] 34 connecting elements
[0133] 35 Corrugated Pipe
[0134] 36 Corrugated Pipe
[0135] 37 Fluid Flow Channel
[0136] 38 fluid flow channels
[0137] 39 Check Valve
[0138] 40 Check Valve
[0139] A1 Actuation direction of the first piezoelectric actuator
[0140] A2 Actuation direction of the second piezoelectric actuator
Claims
1. A first and second piezoelectric actuator (7, 8) controlling at least two interacting elements; 7.1，7.2； 8.1, 8.2) A method for attaching a friction element (9) to which it is commonly displaced, the method comprising the steps of: a. Step A: Apply a first cyclic drive voltage signal (13) with a stable frequency to the first piezoelectric actuator (7; 7.1, 7.2). b. Step B: Apply a second cyclic drive voltage signal (14) with a stable frequency to the second piezoelectric actuator (8; 8.1, 8.2), wherein the first and second cyclic drive voltage signals (13, 14) have the same frequency, and wherein the frequencies of the first and second cyclic drive voltage signals (13, 14) are opposite in phase, characterized in that: For at least a predetermined time period, the first and second cyclic drive voltage signals (13, 14) in steps A and B are synchronized such that at least one time phase is included in which the first and second cyclic drive voltage signals (13, 14) of the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) both have a gradient that decreases or increases the corresponding first and second cyclic drive voltage signals (13, 14) by the same sign.
2. The method according to claim 1, comprising the following time stages: In the first phase, among which... The first piezoelectric actuator (7; 7.1, 7.2) The first cyclic drive voltage signal (13) is increased from the reference voltage (15a) to a first upper intermediate voltage (18a) located between the reference voltage (15a) and the first upper peak voltage (16a), or from the reference voltage (15a) to the first upper peak voltage (16a), and wherein, From the second piezoelectric actuator (8; The second cyclic drive voltage signal (14) of 8.1, 8.2) is reduced from the reference voltage (15b) to a second lower intermediate voltage (17b) located between the reference voltage (15b) and the second lower peak voltage (19b), or reduced from the reference voltage (15b) to the second lower peak voltage (19b). The second time phase, in which... The first piezoelectric actuator (7; 7.1, 7.2) The first cyclic drive voltage signal (13) increases from the first upper intermediate voltage (18a) to the first upper peak voltage (16a), or pauses at the first upper peak voltage (16a), or decreases from the first upper peak voltage (16a) to the first upper intermediate voltage (18a) located between the first upper peak voltage (16a) and the reference voltage (15a), and wherein, From the second piezoelectric actuator (8; The second cyclic drive voltage signal (14) of 8.1, 8.2) increases from the second lower peak voltage (19b) to the second lower intermediate voltage (17b) located between the second lower peak voltage (19b) and the reference voltage (15b), or pauses at the second lower peak voltage (19b), or decreases from the second lower intermediate voltage (17b) to the second lower peak voltage (19b), thereby, during the second time phase, the first and second piezoelectric actuators (7, 8; 7.1，7.2； The first and second cyclic drive voltage signals (13, 14) of 8.1, 8.2) both have gradients that decrease or increase the corresponding first and second cyclic drive voltage signals (13, 14) by the same sign, or one of these gradients is zero while the other is not zero, and In the third time phase, the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) decreases from the first upper peak voltage (16a) or the first upper intermediate voltage (18a) to the first lower intermediate voltage (17a) or the first lower peak voltage (19a), and the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) increases from the second lower intermediate voltage (17b) to the second upper intermediate voltage (18b) or the second upper peak voltage (16b).
3. The method of claim 2, further comprising the following additional time phases: In the fourth time phase, the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) increases from the first lower peak voltage (19a) to the first lower intermediate voltage (17a) located between the first lower peak voltage (19a) and the reference voltage (15a), or pauses at the first lower peak voltage (19a), or decreases from the first lower intermediate voltage (17a) to the first lower peak voltage (19a), and the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) increases from the second upper intermediate voltage (18b) to the second upper peak voltage (16b). Either pause at the second upper peak voltage (16b), or decrease from the second upper peak voltage (16b) to the second upper intermediate voltage (18b) located between the second upper peak voltage (16b) and the reference voltage (15b), wherein, in the fourth time phase, the first and second cyclic drive voltage signals (13, 14) of the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) both have gradients of the same sign that decrease or increase the corresponding first and second cyclic drive voltage signals (13, 14), or one of these gradients is zero and the other is not zero, or both of these gradients are zero, or wherein the fourth time phase is omitted, and In the fifth time phase, the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) increases from the first lower intermediate voltage (17a) or the first lower peak voltage (19a) to the reference voltage (15a), and the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) decreases from the second upper intermediate voltage (18b) or the second upper peak voltage (16b) to the reference voltage (15b).
4. The method according to claim 3, characterized in that, in the second time phase, the gradient amount of increasing or decreasing the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) is less than the gradient amount of decreasing the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) in the third time phase, and / or, in the second time phase, the amount of increasing or decreasing the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) is less than the gradient amount of increasing the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) in the third time phase.
5. The method according to claim 4, characterized in that, the gradient amount of increasing the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) in the first time phase is different from the gradient amount of increasing, decreasing or pausing the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) in the second time phase, and / or, the gradient amount of decreasing the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) in the first time phase is different from the gradient amount of increasing, decreasing or pausing the second cyclic drive voltage signal (14) of the second piezoelectric actuator (8; 8.1, 8.2) in the second time phase.
6. The method according to claim 5, wherein the amount of the first upper peak voltage (16a) is different from the amount of the first lower peak voltage (19a) and / or the amount of the second upper peak voltage (16b) and / or the amount of the second lower peak voltage (19b).
7. The method according to claim 6, characterized in that the gradient amount of the first cyclic drive voltage signal (13) of the first piezoelectric actuator (7; 7.1, 7.2) being increased, decreased, or paused in the fourth time phase is different from the increase or decrease of the first piezoelectric actuator (7; 7.1, 7.2) in the fifth time phase and / or the third time phase. The gradient amount of the first cyclic drive voltage signal (13) of 7.1, 7.2), and / or, in the fourth time phase, increasing or decreasing or pausing the second piezoelectric actuator (8); The gradient amount of the second cyclic drive voltage signal (14) of 8.1, 8.2) is different from the reduction or decrease of the second piezoelectric actuator (8) in the fifth time phase and / or the third time phase. The gradient of the second cyclic drive voltage signal (14) of 8.1, 8.2).
8. The method according to claim 7, characterized in that, The first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) are generated by a cyclic first excitation voltage (20, 22) applied to the first terminal (12a) and a cyclic second excitation voltage (21, 23) applied to the second terminal (12b) of the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2). 7.1，7.2； The first and second cyclic drive voltage signals (13, 14) of 8.1, 8.2) have the first terminal (12a) being the positive terminal and the second terminal (12b) being the negative terminal, and the amount of the upper peak voltage of the cyclic first excitation voltage (20, 22) being higher than the amount of the lower peak voltage of the cyclic first excitation voltage (20, 22), and the amount of the upper peak voltage of the cyclic second excitation voltage (21, 23) being lower than the amount of the upper peak voltage or the lower peak voltage of the cyclic first excitation voltage (20, 22).
9. The method according to claim 8, characterized in that, The upper peak voltage of the first cyclic excitation voltage (20, 22) is synchronized with the upper peak voltage of the second cyclic excitation voltage (21, 23) and is applied simultaneously.
10. The method according to claim 9, characterized in that, The object to which the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) are displaced together and attached is at least one friction element (9) of an inertial drive motor (1), wherein the at least one friction element (9) is configured to be at least in the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2); 7.1，7.2； In the non-operating state of 8.1, 8.2), it makes frictional contact with the element to be driven (2).
11. The method according to claim 10, characterized in that, The inertial drive motor (1) includes an elastic frame (3), at least one friction element (9) arranged on the elastic frame (3), and the first and second piezoelectric actuators (7, 8). 7.1, 7.2; 8.1, 8.2), the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) are configured to cause deformation of the elastic frame (3) by interaction through the use of corresponding first and second cycle drive voltage signals (13, 14).
12. The method according to claim 11, characterized in that, The first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) are configured to displace at least one friction element (9) in frictional contact with the driven element (2) in a forward direction during a first time phase, retract at least one friction element (9) from the driven element (2) during a second time phase, and displace at least one friction element (9) in a rearward direction during a third time phase.
13. The method according to claim 12, characterized in that, The elastic frame (3) is attached to a portion of a lever structure, the lever structure including a column (24), on which at least one friction element (9) is arranged, powered by the first and second piezoelectric actuators (7, 8). 7.1，7.2； The deformation of the elastic frame (3) caused by the interaction of 8.1, 8.2) is amplified by the lever structure and transferred to the at least one friction element (9).
14. The method according to claim 13, characterized in that, At least three of the first and second piezoelectric actuators (7.1, 7.2; 8.1, 8.2) are provided, configured to be jointly displaced and attached to the at least one friction element (9), thereby the first and second piezoelectric actuators ( 7.1, 7.2; 8.1, 8.2) are controlled by their corresponding first and second cycle drive voltage signals (13, 14) to shift the at least one of the friction elements (9) in the x and z directions and to retract the at least one friction element (9) from the driven element (2) in the y direction.
15. The method according to claim 13, characterized in that, Four of the first and second piezoelectric actuators (7.1, 7.2; 8.1, 8.2) are provided, configured to be jointly displaced and attached to the at least one friction element (9), thereby the first and second piezoelectric actuators ( 7.1, 7.2; 8.1, 8.2) are controlled by their corresponding first and second cycle drive voltage signals (13, 14) to shift the at least one of the friction elements (9) in the x and z directions and to retract the at least one friction element (9) from the driven element (2) in the y direction.
16. The method according to any one of claims 1 to 10, characterized in that, The object that is jointly moved by the first and second piezoelectric actuators (7, 8) and attached to them is the central moving mass block (31) of the piezoelectric hydraulic actuator (30).
17. An assembly comprising two interacting first and second piezoelectric actuators (7, 8); 7.1, 7.2; 8.1, 8.2), attached to the first and second piezoelectric actuators (7, 8; 7.1，7.2； 8.1, 8.2) a displaceable object, and the first and second piezoelectric actuators (7, 8) for applying and controlling the control of displacement of the object. 7.1，7.2； A means for the interaction of first and second cyclic drive voltage signals (13, 14) of 8.1, 8.2), wherein the means for applying and controlling are configured to perform the method according to any one of the preceding claims.
18. The component according to claim 17, characterized in that, The device is equipped with driving electronics having two signal sources, each having an active terminal and a passive terminal, wherein only the active terminal is electrically connected to the positive or negative terminal of the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2), the other of the positive or negative terminals of the first and second piezoelectric actuators (7, 8; 7.1, 7.2; 8.1, 8.2) is electrically connected to each other such that they are floating, and the passive terminals of the two signal sources are grounded.