JP5867040B2 - Electrostatic actuator, electrostatic actuator control method, and stator - Google Patents

Description

  The present invention relates to an electrostatic actuator, an electrostatic actuator control method, and a stator.

  2. Description of the Related Art Conventionally, there is an electrostatic actuator having a stator provided with electrodes and a mover provided with a resistor such as a film. Such an electrostatic actuator employs a method of driving with signals of a plurality of phases.

  Here, in such an electrostatic actuator, when the slider is linearly moved on the stator, the slider may meander or move to the left and right due to in-plane variations in frictional resistance or foreign matter. There is.

  In order to solve such a problem, the conventional electrostatic actuator has a technique of providing a guide for preventing the moving member from meandering and biasing to the left and right. However, the movement of the moving element is hindered by the frictional resistance between the guide and the moving element, and unnecessary charging may occur due to the friction between the guide and the moving element. Furthermore, the force to return the moving element to the center does not work only by being regulated by the position of the guide.

  Therefore, there is a conventional electrostatic actuator in which voltage supply lines are provided on both sides of the electrode along the moving direction of the moving element (see, for example, Patent Document 1). Thereby, the moment component perpendicular to the moving direction of the moving element is fixed by the electrostatic force of the two voltage supply lines on both sides of the electrode. Therefore, the generation of the rotational moment of the mover is suppressed, and the meandering of the mover is prevented.

  Here, some of the conventional electrostatic actuators detect the position of the moving element using an optical sensor. However, such an optical sensor has a problem that predetermined detection cannot be performed when it is affected by outside light, particularly infrared light. Furthermore, it is necessary to provide a hole for the optical sensor on the surface of the stator. There is a possibility that foreign matter may be mixed in the hole, and there is a problem that the design property is lowered due to the hole. .

JP-A-3-65081

  The present invention provides an electrostatic actuator capable of detecting the position of a moving element without being affected by external light.

An electrostatic actuator according to an aspect of the present invention is provided.
A stator,
A mover disposed on the stator;
A control device that outputs a signal to the stator to control the operation of the movable element,
The stator is
A substrate having one side and the other side;
A plurality of main operation linear electrodes provided independently on one surface of the substrate and arranged in parallel to each other at equal intervals;
Detection provided on one surface of the substrate, adjacent to the plurality of main operation linear electrodes in a direction orthogonal to the plurality of main operation linear electrodes, and arranged in parallel to the plurality of main operation linear electrodes. A linear electrode;
Provided on one surface of the substrate, arranged in parallel with the detection linear electrode and electrically connected to the ground so that the detection linear electrode is positioned between the plurality of main operation linear electrodes. And a ground electrode,
The controller is
The movement based on a detection signal corresponding to a change in potential difference between the detection linear electrode and the ground electrode due to a change in the distance between the charged movable element and the detection linear electrode. It is an electrostatic actuator characterized by detecting the position of a child.

In the electrostatic actuator,
The controller is
You may have an arithmetic circuit which acquires the electric potential difference signal according to the said electric potential difference in the timing which the signal applied to the said linear electrode for main operation | movement of the said stator does not change.

In the electrostatic actuator,
The arithmetic circuit is:
The detection signal included in the potential difference signal may be extracted by recognizing a pattern of the potential difference signal corresponding to the potential difference and removing a pulse wave included in the potential difference signal.

In the electrostatic actuator,
The controller is
An analog / digital converter that performs analog / digital conversion on the potential difference signal may be further included.

In the electrostatic actuator,
The controller is
A low-pass filter for filtering the potential difference signal may be provided.

In the electrostatic actuator,
The controller is
Based on the detection signal, it may be determined that the movable element is in a state of being close to the detection linear electrode.

In the electrostatic actuator,
The controller is
When the detection signal is detected a plurality of times in succession, it may be determined that the movable element is in a state of being close to the detection linear electrode.

In the electrostatic actuator,
The controller is
When the detection signal is detected, driving of the moving element may be stopped, or the moving element may be driven in the reverse direction.

In the electrostatic actuator,
The controller is
When the detection signal is detected, the moving element may be driven as it is for a predetermined period, and then the driving of the moving element may be stopped or the moving element may be driven in the reverse direction.

In the electrostatic actuator,
The width of the detection linear electrode may be larger than the width of the main operation linear electrode.

In the electrostatic actuator,
The width of the detection linear electrode may be three times the width of the main operation linear electrode.

In the electrostatic actuator,
The wiring connected to the detection linear electrode and the wiring connected to the ground electrode may be positioned between two protective ground wirings electrically connected to the ground.

In the electrostatic actuator,
Of the four main operation linear electrodes included in the plurality of main operation linear electrodes, a rectangular wave whose phase is inverted to the first main operation linear electrode and the third main operation linear electrode, respectively. Signal is input,
A rectangular wave signal whose phase is inverted is input to the second main operation linear electrode and the fourth main operation linear electrode,
Two signals input to two adjacent electrodes may have the same intensity by being shifted by a quarter period.

An electrostatic actuator control method according to an aspect of the present invention includes:
A stator and a mover disposed on the stator, and the stator is provided on one surface of the substrate independently of the substrate having one surface and the other surface, and is parallel to each other. A plurality of main operation linear electrodes arranged at intervals, provided on one surface of the substrate, adjacent to the plurality of main operation linear electrodes in a direction perpendicular to the plurality of main operation linear electrodes, and the plurality of The detection linear electrode is disposed between the detection linear electrode arranged in parallel to the main operation linear electrode and the plurality of main operation linear electrodes provided on one surface of the substrate. And a ground electrode arranged in parallel to the detection linear electrode and electrically connected to the ground,
The movement based on a detection signal corresponding to a change in potential difference between the detection linear electrode and the ground electrode due to a change in the distance between the charged movable element and the detection linear electrode. An electrostatic actuator control method is characterized in that the position of a child is detected.

The stator according to one aspect of the present invention is:
A substrate having one side and the other side;
A plurality of main operation linear electrodes provided independently on one surface of the substrate and arranged in parallel to each other at equal intervals;
Detection provided on one surface of the substrate, adjacent to the plurality of main operation linear electrodes in a direction orthogonal to the plurality of main operation linear electrodes, and arranged in parallel to the plurality of main operation linear electrodes. A linear electrode;
Provided on one surface of the substrate, arranged in parallel with the detection linear electrode and electrically connected to the ground so that the detection linear electrode is positioned between the plurality of main operation linear electrodes. And a ground electrode.

  According to the electrostatic actuator according to the present invention, the position of the moving element can be detected without being affected by external light.

FIG. 1 is a perspective view showing an example of the configuration of an electrostatic actuator 100 according to the present invention. FIG. 2 is a top view schematically showing the electrostatic actuator 100 shown in FIG. FIG. 3 is a cross-sectional view showing a cross section of the electrostatic actuator 100 along the line AA in FIG. FIG. 4 is a cross-sectional view showing a cross section of the electrostatic actuator 100 along the line BB in FIG. FIG. 5 is a waveform diagram showing an example of waveforms of signals a to d applied to the main operation linear electrodes 1 a to 1 d. FIG. 6 is a waveform diagram showing an example of waveforms of signals s to v applied to the auxiliary operation linear electrodes 1 s to 1 v. FIG. 7 is a block diagram showing an example of the configuration of the control device CON shown in FIG. FIG. 8 is a diagram illustrating an example of a configuration of a region in the vicinity of the detection linear electrodes G1 and G2 of the electrostatic actuator 100 of FIG. FIG. 9 is a diagram illustrating an example of the potential difference signal. FIG. 10 is a diagram illustrating an example of the potential difference signal filtered by the low-pass filter.

  Embodiments of an electrostatic actuator according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing an example of the configuration of an electrostatic actuator 100 according to the present invention. FIG. 2 is a top view schematically showing the electrostatic actuator 100 shown in FIG. 3 is a cross-sectional view showing a cross section of the electrostatic actuator 100 along the line AA in FIG. FIG. 4 is a cross-sectional view showing a cross section of the electrostatic actuator 100 along the line BB in FIG. For simplicity, the control device is omitted in FIG. Further, in FIG. 2, the cover film 103 and the sliding structure film 104 are omitted.

  As shown in FIGS. 1 and 2, the electrostatic actuator 100 includes a stator 1, a mover 2, and a control device CON.

  The stator 1 includes a substrate 102 having one surface 102a and another surface 102b, and at least four linear electrodes 1a for main operation that are provided independently on each surface 102a of the substrate 102 and arranged in parallel to each other at equal intervals. 1d and a plurality of auxiliary operation linear electrodes 1s to 1v which are provided independently on one surface 102a of the substrate 102 and arranged at equal intervals in parallel to each other, and a plurality of main motions provided on one surface of the substrate 102. Detection linear electrode D1 arranged adjacent to the plurality of main operation linear electrodes 1a to 1d in parallel to the plurality of main operation linear electrodes 1a to 1d in a direction orthogonal to the working linear electrodes 1a to 1d. , D2 and parallel to the detection linear electrodes G1 and G2 so that the detection linear electrodes G1 and G2 are positioned between the main operation linear electrodes 1a to 1d. Arranged and gra A ground electrode G1, G2 that are electrically connected to de, a.

  The mover 2 is movably disposed on the stator 1.

  The control device CON outputs signals a to d and s to v to the stator 1 to control the operation of the mover 2. Further, the control device CON detects the position of the movable element 2 based on the voltage signals SD1, SD2, SG1, and SG2, and determines the operation of the movable element 2 according to the detection result.

  In the following description, auxiliary operation linear electrodes 1s to 1v extending in a direction orthogonal to the main operation linear electrodes 1a to 1d on one side of the main operation linear electrodes 1a to 1d (lower side in FIG. 2) will be described. An auxiliary operation line which is called a one-side auxiliary operation linear electrode and extends in a direction perpendicular to the main operation linear electrodes 1a to 1d on the other side (upper side in FIG. 2) of the main operation linear electrodes 1a to 1d. The electrode 1s-1v may be referred to as the other-side auxiliary operation linear electrode.

  Hereinafter, the stator 1 will be further described in detail. As described above, the stator 1 is provided on the substrate 102, at least four main operation linear electrodes 1 a to 1 d provided on the one surface 102 a of the substrate 102, and the one surface 102 a of the substrate 102. And a plurality of auxiliary operation linear electrodes 1s to 1v.

  Here, out of the four main operation linear electrodes 1a to 1d, the first main operation linear electrode 1a and the third main operation linear electrode 1c are each a rectangular wave signal or a sine whose phase is inverted. A wave signal is input, and a rectangular wave signal or a sine wave signal with inverted phases is input to the second main operation linear electrode 1b and the fourth main operation linear electrode 1d.

  In addition, two signals input to two adjacent electrodes, for example, the first main operation linear electrode 1a and the second main operation linear electrode 1b are shifted by a quarter period and have the same intensity. have.

  Further, the main operation linear electrodes 1a to 1d are arranged on one side (lower side in FIG. 2) in a direction orthogonal to the four main operation linear electrodes 1a to 1d, and the first A first main operation bus line 101a and a second main operation bus line 101b connected to the main operation linear electrode 1a and the second main operation linear electrode 1b, respectively, are provided in parallel to each other.

  Further, on the other side of the four main operation linear electrodes 1a to 1d (upper side in FIG. 2), it extends in a direction perpendicular to the four main operation linear electrodes 1a to 1d and is for the third main operation. A third main operation bus line 1c and a fourth main operation bus line 1d connected to the linear electrode 1c and the fourth main operation linear electrode 1d are provided in parallel to each other.

  In addition, as described above, a plurality of main operation linear electrodes 1a to 1d extending on one side (the lower side in FIG. 2) in a direction perpendicular to the four main operation linear electrodes 1a to 1d. One side auxiliary operation linear electrodes 1s to 1v are provided (here, a set of four units is a total of eight sets of two units).

  Further, as described above, a plurality (in this case,) extending in the direction orthogonal to the four main operation linear electrodes on the other side (upper side in FIG. 2) of the four main operation linear electrodes 1a to 1d. The other side auxiliary operation linear electrodes 1s to 1v are provided.

  The plurality of one-side auxiliary operation linear electrodes 1 s to 1 v and the plurality of other side auxiliary operation linear electrodes 1 s to 1 v are the four main operations on both sides of the four main operation linear electrodes. They are arranged symmetrically around the working line electrodes 1a to 1d (in this embodiment, eight are arranged with the same wiring rule).

  The plurality of one-side auxiliary operation linear electrodes 1s to 1v may be provided in a larger number than the plurality of other side auxiliary operation linear electrodes 1s to 1v. Thereby, for example, when the force (gravity) is applied in a direction in which the movable element 2 moves away from the center of the stator 1, such as when the electrostatic actuator 100 is fixed to the wall, the direction opposite to the direction of this force (this In this case, it is possible to make the auxiliary force work more in the auxiliary operation direction Z).

  Further, since the auxiliary operation linear electrodes 1s to 1v are provided on both sides of the main operation linear electrodes 1a to 1d, the auxiliary operation linear electrodes 1s to 1v can be used not only for the purpose of correcting the position of the moving element 2. Further, it is possible to move the moving element 2 in a zigzag manner with respect to the main operation direction X by actively using the auxiliary operation directions Y and Z orthogonal to the main operation direction X.

  Of the four one-side auxiliary operation linear electrodes 1s to 1v, the first one-side auxiliary operation linear electrode 1s and the third one-side auxiliary operation linear electrode 1u are each phased. A rectangular wave signal or a sine wave signal that is inverted is input to the second one-side auxiliary operation linear electrode 1t and the fourth one-side auxiliary operation linear electrode 1v. A signal or sine wave signal is input.

  Then, two adjacent one-side auxiliary operation linear electrodes, for example, two input to the first one-side auxiliary operation linear electrode 1s and the second first-side auxiliary operation linear electrode 1t The signals have the same intensity, shifted by a quarter period.

  That is, a rectangular wave signal or a sine wave signal having different phases is input to the plurality of one-side auxiliary operation linear electrodes 1s to 1v, and the movement is close to the plurality of one-side auxiliary operation linear electrodes 1s to 1v. The child 2 is moved to the four main operation linear electrodes 1a to 1d (auxiliary operation direction Z).

  Among the four other side auxiliary operation linear electrodes 1s to 1v, the phase is shifted to the first other side auxiliary operation linear electrode 1s and the third other side auxiliary operation linear electrode 1u. A rectangular wave signal or a sine wave signal that is inverted is input to the second other-side auxiliary operation linear electrode 1t and the fourth other-side auxiliary operation linear electrode 1v. A signal or sine wave signal is input.

  Then, two adjacent auxiliary operation linear electrodes, for example, two input to the first other auxiliary operation linear electrode 1s and the second other auxiliary operation linear electrode 1t are input. The signals have the same intensity, shifted by a quarter period.

  That is, rectangular wave signals or sine wave signals having different phases are input to the plurality of other side auxiliary operation linear electrodes 1 s to 1 v, and the movement is close to the plurality of other side auxiliary operation linear electrodes 1 s to 1 v. The child 2 is moved to the four main operation linear electrodes 1a to 1d (auxiliary operation direction Y).

  Further, as shown in FIG. 2, the first auxiliary operation bus line 101s and the second auxiliary operation line electrode 1s connected to the first auxiliary operation linear electrode 1s and the second auxiliary operation linear electrode 1t, respectively. The auxiliary operation bus lines 101t are provided in parallel to each other.

  Furthermore, a third auxiliary operation bus line 101u and a fourth auxiliary operation bus line 101v connected to the third auxiliary operation linear electrode 1u and the fourth auxiliary operation linear electrode 1v, respectively. Are provided in parallel to each other.

  Further, as shown in FIGS. 3 and 4, a cover film 103 is provided to cover the main operation linear electrodes 1a to 1d and the auxiliary operation linear electrodes 1s to 1v provided on one surface 102a of the substrate 102, Further, a sliding structure film 104 is provided so as to cover the cover film 103.

  By the way, the substrate 102 has a thickness of, for example, 25 μm. Examples of the material used for the substrate 102 include polyimide, glass epoxy resin, phenol resin, PET (polyethylene terephthalate), PET-G (terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer), and PEN (polyethylene naphthalate). ), PP (polypropylene), PE (polyethylene), PC (polycarbonate), PA (polyamide), PPS (polyphenylene sulfide), polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, cellulose diacetate, cellulose triacetate, polystyrene System, ABS, polyacrylate, polyethylene, polyurethane, etc. are selected. In particular, polyimide is preferable because of its high heat resistance and high strength.

  In addition, as described above, the main operation linear electrodes 1a to 1d and the auxiliary operation linear electrodes 1s to 1v are provided independently on the one surface 102a of the substrate 102, and are comb-like in parallel to each other at equal intervals. It is arranged repeatedly. The main operation linear electrodes 1a to 1d and the auxiliary operation linear electrodes 1s to 1v have, for example, a wiring pitch set to 0.3 mm or less, and the main operation linear electrodes 1a to 1d and the auxiliary operation linear electrodes 1a to 1d. The linear electrodes 1s to 1v have a thickness of, for example, about 18 μm when copper is formed as an electrode material on a polyimide substrate (see FIGS. 2 to 4).

  Further, as shown in FIG. 2, the two first and second main operation bus lines 101a and 101b each have a strip shape, and one side of the main operation linear electrodes 1a to 1d (see FIG. 2). On the lower side).

  Among these, the first main operation bus line 101a is provided on one surface (upper surface) 102a of the substrate 102, and the first main operation bus line 101a is electrically connected to the first main operation linear electrode 1a. Has been.

  The second main operation bus line 101b is provided on the other surface (lower surface) 102b of the substrate 102, and is electrically connected to the second main operation linear electrode 1b. The substrate 102 is provided with through-hole wiring 1b2 that penetrates the substrate 102 and is connected to the second main operation bus line 101b provided on the other surface 102b of the substrate 102. Further, a pad electrode 1b1 for connecting one side of the second main operation linear electrode 1b and the through-hole wiring 1b2 is provided on the one surface 102a of the substrate 102.

  As a result, the second main operation bus line 101b is electrically connected to the second main operation line electrode 1b.

  Further, the two third and fourth main operation bus lines 101c and 101d each have a strip shape, and are provided on the other side (upper side in FIG. 2) of the main operation linear electrodes 1a to 1d as described above. ing.

  The third main operation bus line 101c is provided on one surface (upper surface) 102a of the substrate 102 and is electrically connected to the third main operation linear electrode 1c.

  The fourth main operation bus line 101d is provided on the other surface (lower surface) 102b of the substrate 102 and is electrically connected to the fourth main operation linear electrode 1d. Here, the substrate 102 is provided with through-hole wiring 1 d 2 that penetrates the substrate 102 and is connected to the fourth main operation bus line 101 d provided on the other surface 102 b of the substrate 102. A pad electrode 1d1 for connecting one side of the fourth main operation linear electrode 1d and the through-hole wiring 1d2 is provided on one surface (upper surface) 102a of the substrate 102.

  Thus, the fourth main operation bus line 101d is electrically connected to the fourth main operation line electrode 1d.

  As shown in FIG. 2, the two first and second auxiliary operation bus lines 101s and 101t are each provided in a strip shape. The lower right 101s and 101t are connected to external connection terminals 100s and 100t, respectively (not shown).

  Of these, the first auxiliary operation bus line 101s is provided on one surface (upper surface) 102a of the substrate 102, and the first auxiliary operation bus line 101s is electrically connected to the first auxiliary operation linear electrode 1s. Connected.

  The second auxiliary operation bus line 101t is provided on the other surface (lower surface) 102b of the substrate 102 and is electrically connected to the second auxiliary operation linear electrode 1t. In addition, the substrate 102 is provided with a through-hole wiring 1t2 that penetrates the substrate 102 and is connected to the second auxiliary operation bus line 101t provided on the other surface 102b of the substrate 102. Furthermore, a pad electrode 1t1 for connecting one side of the second auxiliary operation linear electrode 1t and the through-hole wiring 1t2 is provided on the one surface 102a of the substrate 102.

  As a result, the second auxiliary operation bus line 101t is electrically connected to the second auxiliary operation linear electrode 1t.

  The two third and fourth auxiliary operation bus lines 101u and 101v are each provided in a strip shape. The lower left 101u and 101v are connected to connection terminals 100u and 100v to the outside although not shown.

  The third auxiliary operation bus line 101u is provided on one surface (upper surface) 102a of the substrate 102 and is electrically connected to the third auxiliary operation linear electrode 1u.

  The fourth auxiliary operation bus line 101v is provided on the other surface (lower surface) 102b of the substrate 102 and is electrically connected to the fourth auxiliary operation linear electrode 1v. Here, the substrate 102 is provided with through-hole wiring 1v2 that penetrates the substrate 102 and is connected to the fourth auxiliary operation bus line 101v provided on the other surface 102b of the substrate 102. A pad electrode 1v1 for connecting one side of the fourth auxiliary operation linear electrode 1v and the through-hole wiring 1v2 is provided on one surface (upper surface) 102a of the substrate 102.

  Accordingly, the fourth auxiliary operation bus line 101v is electrically connected to the fourth auxiliary operation linear electrode 1v.

  In FIG. 2, the first auxiliary operation bus line 101 s has a partially separated area, and the separated areas are electrically connected via a wiring (not shown). The same applies to the other auxiliary operation bus lines 101t to 101v.

  Next, the cover film 103 and the sliding structure film 104 of the stator 1 will be described in detail with reference to FIGS.

  As shown in FIGS. 3 and 4, the cover film 103 is provided on the substrate 102 so as to cover the main operation linear electrodes 1 a to 1 d and the auxiliary operation linear electrodes 1 s to 1 v. For example, the cover film 103 has a thickness of 12.5 μm. As a material used for the cover film 103, for example, polyimide is selected.

  The sliding structure film 104 is provided on the cover film 103. This sliding structure film 104 has slidability with respect to the lower surface of the moving element 2 (the lower surface of a base film 2a described later). The sliding structure film 104 has a thickness of several nm, for example. For example, silicon is selected as the material used for the sliding structure film 104.

  The distance D from the upper surface of the main operation linear electrodes 1a to 1d and the auxiliary operation linear electrodes 1s to 1v to the charging surface (lower surface) of the resistor film 2b is set to, for example, 30 μm or more and 150 μm or less. .

  Further, as described above, the detection linear electrodes D1 and D2 are provided on one surface of the substrate 102, and the plurality of main operation linear electrodes 1a to 1d in a direction orthogonal to the plurality of main operation linear electrodes 1a to 1d. It is adjacent to 1d and arranged in parallel to the plurality of main operation linear electrodes 1a to 1d.

  Further, as described above, the ground electrodes G1 and G2 are provided on one surface of the substrate 102, and the detection linear electrodes G1 and G2 are positioned between the plurality of main operation linear electrodes 1a to 1d. The detection linear electrodes G1 and G2 are arranged in parallel and are electrically connected to the ground.

  The widths of the detection linear electrodes D1 and D2 are larger than the widths of the main operation linear electrodes 1a to 1d. For example, the width of the detection linear electrodes D1 and D2 is three times the width of the main operation linear electrodes 1a to 1d.

  Next, the moving element 2 will be described in detail with reference to FIGS.

  As shown in FIGS. 1 and 2, the mover 2 is disposed on the stator 1. As shown in FIGS. 3 and 4, the mover 2 includes a base film 2 a and a resistor film 2 b.

  The base film 2a is disposed so as to face and contact the stator 1. The base film 2a has a thickness of about 25 μm, for example.

  Examples of the material used for the base film 2a include PET (polyethylene terephthalate), PET-G (terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer), PEN (polyethylene naphthalate), PP (polypropylene), and PE. (Polyethylene), PC (polycarbonate), PA (polyamide), PPS (polyphenylene sulfide), polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, cellulose diacetate, cellulose triacetate, polystyrene, ABS, polyacrylic ester Polyethylene, polyurethane, etc. are selected. In particular, PET is preferable because it is inexpensive and readily available.

The resistor film 2b is provided on the base film 2a. The resistor film 2b has a thickness of about 1 μm, for example. The resistor film 2b has a surface resistivity in the range of, for example, 10 ¹¹ to 10 ¹³ Ω / □.

  Next, the operation of the present embodiment having the above configuration will be described. First, the case where the movable element 2 is positioned on the main operation linear electrodes 1a to 1d and operates in the main operation direction X will be described.

  First, as shown in FIG. 2, the signals a to d are input to the electrostatic actuator 100 from a drive circuit (not shown) via the first to fourth main operation input terminals 100a to 100d. At this time, the signals a to d are respectively applied to the main operation linear electrodes 1a to 1d through the main operation bus lines 101a to 101d, the through-hole wirings 1b2 and 1d2, and the pad electrodes 1b1 and 1d1. .

  Here, FIG. 5 is a waveform diagram showing an example of waveforms of the signals a to d applied to the main operation linear electrodes 1 a to 1 d. Although FIG. 5 shows the case where the signals a to d are rectangular waves, the same phase relationship is obtained when the signals a to d are sine waves.

  As shown in FIG. 5, the two signals a and b inputted to the adjacent main operation linear electrodes 1a and 1b are shifted by a quarter cycle. Similarly, the two signals b and c inputted to the adjacent main operation linear electrodes 1b and 1c are shifted by a quarter cycle. Similarly, the two signals c and d input to the adjacent main operation linear electrodes 1c and 1d are shifted by a quarter period.

  In this case, the signals a to d have the same intensity (amplitude). Further, the absolute value of the amplitude (voltage) of each signal a to d is set to 800 V or less, for example.

  As a result, the first main operation linear electrode 1a and the third main operation linear electrode 1c each have a phase-inverted signal (phase is shifted by a half cycle) (rectangular wave signal or sine wave signal). a and c are input. The second main operation linear electrode 1b and the fourth main operation linear electrode 1d each have a signal (rectangular wave signal or sine wave signal) b whose phase is inverted (the phase is shifted by a half period). , D are input.

  In this case, the resistor film 2b of the moving element 2 is charged according to the signals a to d applied to the main operation linear electrodes 1a to 1d. And, for example, as shown in FIG. 5, the amplitude of the signals a to d changes, and according to the electrostatic energy accumulated in the charging portion of the moving element 2 and the main operation linear electrodes 1 a to 1 d, The mover 2 moves on the stator 1 in a direction (main operation direction X) perpendicular to the main operation linear electrodes 1a to 1d (FIG. 2).

  Next, a description will be given of a case where the mover 2 moves from the main operation direction X so that the mover 2 is positioned on the one-side auxiliary operation linear electrodes 1s to 1v and receives a force in the auxiliary operation direction Z. To do. The same applies to the case where the mover 2 deviates from the main operation direction X and is positioned on the other-side auxiliary operation linear electrodes 1s to 1v and receives the force in the auxiliary operation direction Y to operate. is there.

  Here, FIG. 6 is a waveform diagram showing an example of waveforms of the signals s to v applied to the auxiliary operation linear electrodes 1s to 1v. FIG. 6 shows the case where the signals s to v are rectangular waves, but the same phase relationship is obtained when the signals s to v are sine waves.

  As shown in FIG. 6, the two signals s and t inputted to the adjacent one-side auxiliary operation linear electrodes 1s and 1t are shifted by a quarter cycle. Similarly, the two signals t and u input to the adjacent one-side auxiliary operation linear electrodes 1t and 1u are shifted by a quarter cycle. Similarly, the two signals u and v inputted to the adjacent one-side auxiliary operation linear electrodes 1u and 1v are shifted by a quarter cycle.

  In this case, the signals s to v have the same intensity (amplitude). Moreover, the absolute value of the amplitude (voltage) of each signal s-v is set to 800 V or less, for example.

  As a result, the first one-side auxiliary operation linear electrode 1s and the third one-side auxiliary operation linear electrode 1u each have a phase-inverted signal (phase is shifted by a half cycle) (rectangular wave). Signal or sine wave signal) s, u. The second one-side auxiliary operation linear electrode 1t and the fourth one-side auxiliary operation linear electrode 1v each have a phase-inverted signal (phase is shifted by a half cycle) (rectangular wave signal). Alternatively, sine wave signals t and v are input.

  In this case, the movable body 2 is charged by the resistor film 2b according to the signals s to v applied to the one-side auxiliary operation linear electrodes 1s to 1v. For example, as shown in FIG. 6, the electrostatic energy accumulated in the charging portion of the moving element 2 and the linear electrodes 1 s to 1 v for one-side auxiliary operation is changed by changing the amplitudes of the signals s to v. Accordingly, the mover 2 receives a force in the direction perpendicular to the one-side auxiliary operation linear electrodes 1s to 1v (auxiliary operation direction Z toward the main operation linear electrode) on the stator 1 and moves ( Figure 2).

  As a result, in the electrostatic actuator 100 according to the present embodiment, even if the moving element 2 deviates from the main operation direction X, the force moves in the auxiliary operation direction Z by approaching the auxiliary operation linear electrodes 1s to 1v. Receive. That is, a moment component is generated in a direction to return the moving element to the center side of the stator, and the moving element 2 operates toward the main operation linear electrode without increasing the frictional resistance of the moving element.

  Next, the configuration and function of the control device CON will be described in detail with reference to FIGS. 2 and 7 to 10. FIG. 7 is a block diagram showing an example of the configuration of the control device CON shown in FIG. FIG. 8 is a diagram illustrating an example of a configuration of a region in the vicinity of the detection linear electrodes G1 and G2 of the electrostatic actuator 100 of FIG. FIG. 9 is a diagram illustrating an example of the potential difference signal. FIG. 10 is a diagram illustrating an example of the potential difference signal filtered by the low-pass filter.

  As described above, the control device CON outputs the signals a to d and s to v to the stator 1 to control the operation of the mover 2.

  Further, the control device CON detects the position of the mover 2 based on the voltage signals SD1, SD2, SG1, and SG2 output from the voltage signal terminals 100D1, 100D2, 100G1, and 100G2 of the stator 1, and the detection result The operation of the mover 2 is determined according to the above.

  This control device CON is configured so that a distance between the charged moving element and the detecting linear electrode changes (approaches or moves away) between the detecting linear electrode D1 and the ground electrode G1. The position of the moving element 2 is detected based on a detection signal corresponding to a change in potential difference (voltage signal SD1−voltage signal SG1).

  That is, the control device CON determines that the movable element 2 is in a state of being close to the detection linear electrode D1 based on the detection signal.

  Similarly, the control device CON determines whether the distance between the charged movable element and the detection linear electrode changes (approaches or moves away) between the detection linear electrode D2 and the ground electrode G2. The position of the moving element 2 is detected based on a detection signal corresponding to a change in potential difference (voltage signal SD2−voltage signal SG2).

  That is, the control device CON determines that the movable element 2 is in the state of being close to the detection linear electrode D2 based on the detection signal.

  The purpose of providing the signal ground electrodes G1 and G2 in the vicinity of the detection linear electrode is to remove common mode noise.

  Further, for example, as illustrated in FIG. 7, the control device CON includes a low-pass filter 10, an analog / digital converter 30 provided in the CPU 20, and an arithmetic circuit 40 provided in the CPU 20.

  The low pass filter 10 filters the potential difference signal. Thereby, noise included in the potential difference signal can be removed to some extent.

  As shown in FIG. 8, the wiring HD1 connected to the detection linear electrode D1 and the wiring HG1 connected to the ground electrode G1 are two protective ground wirings P1 electrically connected to the ground. , P2 may be located.

  As a result, it is possible to reduce inductive noise and the like from neighboring wirings that can be superimposed on the wirings HD1 and HG1.

  Similarly, the wiring HD2 connected to the detection linear electrode D2 and the wiring HG2 connected to the ground electrode G2 are located between two protective ground wirings P3 and P4 electrically connected to the ground. You may do it.

  As a result, it is possible to reduce inductive noise from neighboring wirings that can be superimposed on the wirings HD2 and HG2. That is, the detection signal can be acquired more reliably.

  Further, as shown in FIG. 7, the CPU 20 outputs signals a to d and s to v to drive the mover 2 and detects the position of the mover 2 based on the potential difference signal.

  The analog-to-digital converter 30 performs analog-to-digital conversion on the potential difference signal filtered by the low-pass filter 10 (which means that the analog signal is converted into a digital signal here). Thereby, since the potential difference signal can be recognized as a digital value, pattern recognition described later becomes possible.

  Here, the potential difference signal includes noise other than the detection signal (FIG. 9). This noise includes a pulse wave of induced noise caused by changes in signals applied to the plurality of main operation linear electrodes 1a to 1d. As shown in FIG. 10, even after filtering by the low-pass filter 10, the potential difference signal includes pulse waves due to changes in signals applied to the plurality of main operation linear electrodes 1 a to 1 d.

  Therefore, the arithmetic circuit 40 determines the timing at which the signals applied to the plurality of main operation linear electrodes 1a to 1d of the stator 1 do not change (the timing at which all the rectangular wave signals a to d are at the “High” level or “Low” level). ), A potential difference signal corresponding to the potential difference is acquired. It should be noted that the signal change mentioned here does not include noise that can be ignored.

  Thereby, the detection signal contained in the potential difference signal can be detected at a timing at which noise due to the rectangular wave signals a to d is not superimposed on the voltage difference signal.

  Further, the arithmetic circuit 40 recognizes the pattern of the potential difference signal corresponding to the potential difference, and extracts the detection signal included in the potential difference signal by removing the pulse wave included in the potential difference signal.

  As a result, the detection signal included in the potential difference signal can be more reliably extracted.

  Further, the control device CON may erroneously determine that it is a detection signal due to the influence of noise or the like.

  However, for example, when the mover 2 passes near the detection linear electrode D1, the potential difference (voltage signal SD1−voltage signal SG1) continuously changes according to whether the surface of the mover 2 is charged or not. The number of detection signals corresponding to the number of changes is acquired in the control device CON.

  Therefore, the control device CON determines that the moving element 2 is in the vicinity of the detection linear electrode D1 when the detection signal is continuously detected a plurality of times.

  Thereby, the control device CON can more reliably determine whether or not the moving element 2 is in the state of being close to the detection linear electrode D1.

  Further, when detecting the detection signal, the control device CON stops driving the moving element 2 or drives the moving element 2 in the reverse direction, for example.

  Further, when detecting the detection signal, the control device CON may drive the moving element 2 as it is for a predetermined period and then stop driving the moving element 2 or drive the moving element 2 in the reverse direction. .

  As described above, according to the electrostatic actuator according to the present embodiment, the position of the mover can be detected without being affected by external light.

  Further, according to the electrostatic actuator according to the present embodiment, since it can be formed by wiring only on the same substrate, other elements are not required, the cost is low, and a flat appearance can be provided.

  Further, in the electrostatic actuator according to the present embodiment, since there is no need to provide a hole for the optical sensor on the surface of the stator, there is no problem of foreign matter mixing, and the design property is not impaired. .

  In the above embodiment, at least four auxiliary operation linear electrodes are provided. However, if a force can be applied in the auxiliary operation directions Y and Z toward the main operation linear electrodes, the auxiliary operation linear electrodes are provided. Three or less may be sufficient.

DESCRIPTION OF SYMBOLS 1 Stator 1a 1st main operation line electrode 1b 2nd main operation line electrode 1c 3rd main operation line electrode 1d 4th main operation line electrode 1s, 1sb 1st auxiliary operation line Electrode 1t, 1tb second auxiliary operation linear electrode 1u, 1ub third auxiliary operation linear electrode 1v, 1vb fourth auxiliary operation linear electrode 1b1, 1d1, 1t1, 1u1, 1tb1, 1ub1 pad electrode 1b2, 1d2, 1t2, 1u2, 1tb2, 1ub2 Through-hole wiring 2 Mover 2a Base film 2b Resistive film 100 Electrostatic actuator 100a First main operation input terminal 100b Second main operation input terminal 100c Third main operation Input terminal 100d Fourth main operation input terminal 100s First auxiliary action input terminal 100t Second auxiliary action input terminal 100u Third Auxiliary action input terminal 100v fourth auxiliary action input terminal 101a first main operation bus line 101b second main operation bus line 101c third main operation bus line 101d fourth main operation bus line 101s first auxiliary Operation bus line 101t Second auxiliary operation bus line 101u Third auxiliary operation bus line 101v Fourth auxiliary operation bus line 102 Substrate 103 Cover film 104 Sliding structure films a to d, s to v Signal D1 , D2 detection linear electrodes G1, G2 ground electrodes SD1, SD2, SG1, SG2 voltage signals 100D1, 100D2, 100G1, 100G2 voltage signal terminals HD1, HG1, HD2, HG2 wiring CON control device 10 low-pass filter 20 CPU
30 Analog / digital converter 40 Arithmetic circuit D Distance X Main operation direction Y, Z Auxiliary operation direction

Claims (15)

A stator,
A mover disposed on the stator;
A control device that outputs a signal to the stator to control the operation of the movable element,
The stator is
A substrate having one side and the other side;
A plurality of main operation linear electrodes provided independently on one surface of the substrate and arranged in parallel to each other at equal intervals;
Detection provided on one surface of the substrate, adjacent to the plurality of main operation linear electrodes in a direction orthogonal to the plurality of main operation linear electrodes, and arranged in parallel to the plurality of main operation linear electrodes. A linear electrode;
Provided on one surface of the substrate, arranged in parallel with the detection linear electrode and electrically connected to the ground so that the detection linear electrode is positioned between the plurality of main operation linear electrodes. And a ground electrode,
The controller is
The movement based on a detection signal corresponding to a change in potential difference between the detection linear electrode and the ground electrode due to a change in the distance between the charged movable element and the detection linear electrode. An electrostatic actuator characterized by detecting the position of a child. The controller is
The electrostatic actuator according to claim 1, further comprising an arithmetic circuit that acquires a potential difference signal corresponding to the potential difference at a timing at which a signal applied to the main operation linear electrode of the stator does not change. The arithmetic circuit is:
The detection signal included in the potential difference signal is extracted by recognizing a pattern of the potential difference signal corresponding to the potential difference and removing a pulse wave included in the potential difference signal. Electrostatic actuator. The controller is
The electrostatic actuator according to any one of claims 2 to 3, further comprising an analog-to-digital converter that performs analog-to-digital conversion on the potential difference signal. The controller is
The electrostatic actuator according to any one of claims 2 to 3, characterized in that it comprises a low pass filter for filtering the potential difference signal. The controller is
6. The electrostatic actuator according to claim 1, wherein it is determined that the moving element is in proximity to the detection linear electrode based on the detection signal. 7. The controller is
The electrostatic actuator according to claim 6, wherein when the detection signal is continuously detected a plurality of times, it is determined that the moving element is in a state of being close to the detection linear electrode. The controller is
The electrostatic actuator according to any one of claims 1 to 7, wherein when the detection signal is detected, the driving of the moving element is stopped or the moving element is driven in the reverse direction. . The controller is
The detection unit according to claim 8, wherein when the detection signal is detected, the moving unit is driven as it is for a predetermined period, and then the driving of the moving unit is stopped or the moving unit is driven in the reverse direction. Electrostatic actuator.   10. The electrostatic actuator according to claim 1, wherein a width of the detection linear electrode is larger than a width of the main operation linear electrode. 11.   11. The electrostatic actuator according to claim 10, wherein the width of the detection linear electrode is three times the width of the main operation linear electrode.   The wiring connected to the detection linear electrode and the wiring connected to the ground electrode are located between two protective ground wirings electrically connected to the ground. Item 12. The electrostatic actuator according to any one of Items 1 to 11. Of the four main operation linear electrodes included in the plurality of main operation linear electrodes, a rectangular wave whose phase is inverted to the first main operation linear electrode and the third main operation linear electrode, respectively. Signal is input,
A rectangular wave signal whose phase is inverted is input to the second main operation linear electrode and the fourth main operation linear electrode,
The electrostatic actuator according to any one of claims 1 to 12, wherein two signals input to two adjacent electrodes have the same intensity by being shifted by a quarter period. A stator and a mover disposed on the stator, and the stator is provided on one surface of the substrate independently of the substrate having one surface and the other surface, and is parallel to each other. A plurality of main operation linear electrodes arranged at intervals, provided on one surface of the substrate, adjacent to the plurality of main operation linear electrodes in a direction perpendicular to the plurality of main operation linear electrodes, and the plurality of The detection linear electrode is disposed between the detection linear electrode arranged in parallel to the main operation linear electrode and the plurality of main operation linear electrodes provided on one surface of the substrate. And a ground electrode arranged in parallel to the detection linear electrode and electrically connected to the ground,
The movement based on a detection signal corresponding to a change in potential difference between the detection linear electrode and the ground electrode due to a change in the distance between the charged movable element and the detection linear electrode. A method for controlling an electrostatic actuator, comprising detecting a position of a child. A substrate having one side and the other side;
A plurality of main operation linear electrodes provided independently on one surface of the substrate and arranged in parallel to each other at equal intervals;
Detection provided on one surface of the substrate, adjacent to the plurality of main operation linear electrodes in a direction orthogonal to the plurality of main operation linear electrodes, and arranged in parallel to the plurality of main operation linear electrodes. A linear electrode;
Provided on one surface of the substrate, arranged in parallel with the detection linear electrode and electrically connected to the ground so that the detection linear electrode is positioned between the plurality of main operation linear electrodes. And a ground electrode.

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