JP5573114B2 - Performance controller drive unit - Google Patents

Description

  The present invention relates to a drive device provided with a drive means such as a solenoid for driving a performance operator such as a key, and more particularly to a drive device provided with a position detection means for detecting the position of a movable member.

  The keyboard unit of a natural keyboard instrument that produces live sounds, such as an acoustic piano, is configured so that a hammer that rotates when a key is pressed produces a string, and a jack or wippen is provided between the key and the hammer. An action mechanism is provided. By this action mechanism, a unique reaction force is applied from the key to the performer's finger, and the keyboard unit of the natural keyboard instrument provides a key touch feeling peculiar to each instrument.

  On the other hand, the keyboard unit of an electronic keyboard instrument that generates an electronic sound is equipped with a spring and a mass body (pseudo hammer) that return the key to its initial position when the key is pressed. Simulates the feeling. However, an electronic keyboard instrument is a device that generates an electronic sound by pressing a key, and does not have a mechanism for actually striking a string to produce sound, and therefore does not have a complicated action mechanism like a natural keyboard instrument. Therefore, the key touch feeling generated by the action mechanism of the natural keyboard instrument cannot be faithfully reproduced, and the key touch feeling of the electronic keyboard instrument is strictly different from the key touch feeling of the natural keyboard instrument.

  Therefore, for electronic keyboard instruments, a key driving device and a control device (force control means) that change the reaction force against the key press have been proposed for the purpose of obtaining a key motion or key touch feeling similar to a natural keyboard instrument. . As an example of this, the keyboard unit described in Patent Document 1 includes an actuator (solenoid) for driving a key, and a control means for controlling the actuator, thereby arbitrarily adjusting the key touch feeling. It is designed to simulate the performance of natural keyboard instruments. In this case, by providing position detection means for detecting position (displacement) information of the plunger of the solenoid, the solenoid is driven and controlled based on the detection signal of the position detection means, and the driving force or reaction force of the key is controlled. Control is to be performed.

  As a specific example of such position detection means, the keyboard device described in Patent Document 2 includes a reflective optical sensor for detecting the position of the plunger of the solenoid. That is, the keyboard device described in Patent Document 2 has a tone pattern in which the color tone is changed so as to exhibit a characteristic in which the light reflection characteristics gradually increase or decrease in parallel with the movement direction of the plunger, and a change in the tone of the tone pattern. A position sensor unit including a light reflection type sensor that detects the movement of the plunger by a change in the amount of reflected light according to the above.

Japanese Patent No. 2956180 JP 2005-195619 A

  By the way, in an actuator provided with a reciprocating plunger, it is necessary to provide a slight gap (clearance) between the plunger and a bearing supporting the plunger in order to ensure a smooth operation of the plunger. In particular, the gap between the plunger and the bearing needs to be set larger in order to allow the plunger to tilt as the distance between the bearings arranged at both ends of the plunger increases with the coil interposed therebetween. However, by providing this gap, there is a possibility that a slight backlash may occur in the operation of the plunger. Then, there is a problem in that the position of the reflected light from the position sensor is shaken due to the backlash, so that the position of the plunger cannot be stably detected and the position detection accuracy cannot be improved.

  As the position detecting means for detecting the position of the plunger, there are an optical digital sensor, a differential transformer type sensor, a magnetic scale type sensor and the like in addition to the reflection type optical sensor as described above. However, since the optical digital sensor has a complicated structure, the mechanism is large and a large installation space is required. The differential transformer type sensor requires a circuit such as excitation and a detection coil, and it is expensive to include them. The magnetic scale type sensor is not suitable for detecting the position of the solenoid plunger because the leakage magnetic field from the solenoid becomes noise and the detection accuracy is lowered.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a performance operator provided with a position detection means capable of improving the position detection accuracy of the movable member while having a simple and inexpensive configuration. It is in providing the drive device of.

  In order to solve the above-described problems, a driving device for a performance operator according to the present invention includes a movable member (46) for applying a driving force to the performance operator (20), and a movable member (46) reciprocating in the axial direction. The guide part (43) that is supported so as to be movable and rotatable about the axis, and the contact part (48a) provided on the movable member (46) abut on the contacted part (48b) provided on the fixed side. A rotation restricting portion (48) for restricting the rotation of the movable member (46), a drive source (41) for driving the movable member (46), and a position detection for detecting the position of the movable member (46). The position detection means (47) includes a moving element (110) having a moving electrode (112) provided on the movable member (46) side, and an induction electrode (103) provided on the fixed side. And a stator (101) having a potential detection electrode (104). A voltage is applied to the induction electrode (103) of the child (101), and the potential distribution generated in the moving electrode (112) by electrostatic induction is detected by the potential detection electrode (104), thereby moving the movable element relative to the stator (101). (110) is a so-called electrostatic encoder configured to detect the position, and the moving element (110) of the position detecting means (47) is plate-like and has elasticity against surface deflection, and one end is a free end. The movable member (46) is attached to the movable member (46) so that the movable member (110) is in contact with the stator (101) in a bent state. The contact portion (48a) of the rotation restricting portion (48) is in contact with the contacted portion (48b) by the biasing force.

According to the driving device for a performance operator according to the present invention, by adopting the above configuration, it is possible to effectively improve the position detection accuracy by the position detecting means without complicating the structure of the driving device. That is, as a position detection means for detecting the position of the movable member, a small and thin electrostatic encoder with excellent position detection performance is used, so that the position detection accuracy of the movable member can be improved with a simple and inexpensive configuration. Can be improved. Further, in the electrostatic encoder, since there is no need to connect a wiring to the moving element, the movement of the movable member to which the moving element is attached is not hindered, and the smooth operation of the driving means can be ensured.
Further, the position detection means includes a plate-like moving element having elasticity against the bending of the surface, and is configured to press the moving element against the stator in a bent state. The electrode surface of the stator can be reliably contacted, and the position detection accuracy of the movable member by the electrostatic encoder can be further improved.
In addition, since the elastic plate-like moving element is in contact with the stator in a bent state, an urging force in the rotational direction is generated on the movable member, and the urging force is applied to the rotation restricting portion. The contact portion is in contact with the contacted portion so that the rotation of the movable member is restricted. Thereby, it is possible to effectively prevent the play of the movable member that is guided by the guide portion and reciprocates in the axial direction. Therefore, it is possible to prevent a decrease in position detection accuracy due to the play of the movable member.
As described above, the position detection accuracy of the movable member can be improved with a simple and inexpensive configuration.

  In addition to the above-described configuration, the driving device for a performance operator according to the present invention biases the electrode surface (112) of the mover (110) against the electrode surface (104) of the stator (101). It is good to further provide a urging member (37). According to this, since the electrode surface of the mover can be brought into uniform contact with the electrode surface of the stator by the urging of the urging member, the clearance of the electrode surface can be stabilized and the position detection can be performed. The position detection accuracy of the means can be further improved.

In another aspect of the drive device for a performance operator according to the present invention, the movable member (46) for applying a driving force to the performance operator (20) and the movable member (46) reciprocate in the axial direction. The guide part (43) that is supported so as to be movable and rotatable about the axis, and the contact part (48a) provided on the movable member (46) abut on the contacted part (48b) provided on the fixed side. A rotation restricting portion (48) for restricting the rotation of the movable member (46), a drive source (41) for driving the movable member (46), and a position detection for detecting the position of the movable member (46). The position detection means (47) includes a moving element (110) having a moving electrode (112) provided on the movable member (46) side, and an induction electrode (103) provided on the fixed side. And a stator (101) having a potential detection electrode (104) A voltage is applied to the induction electrode (103) of (101), and the potential distribution generated in the movement electrode (112) by electrostatic induction is detected by the potential detection electrode (104), whereby the mover ( 110), and the moving element (110) of the position detecting means (46) is composed of a plate-like member attached to the movable member (46) so that one end is a free end. There is provided a biasing member (37) that biases the electrode surface of the child (110) against the electrode surface of the stator (101), and the mover (110) is attached to the stator (101). By being urged by the urging member (37), the abutting portion (48a) of the rotation restricting portion (48) abuts on the abutted portion (48b) by the urging force of the urging member (37) . The rotation of the movable member (46) is restricted. To.

According to this configuration, the electrostatic position encoder is used as the position detection unit, as in the drive device having another configuration described above, so that the position detection accuracy of the movable member can be effectively achieved while the configuration is simple and inexpensive. Can be improved. In addition, by providing an urging member that urges the electrode surface of the mover against the electrode surface of the stator, the electrode surface of the mover and the electrode surface of the stator are uniformly contacted. Therefore, the clearance of the electrode surface can be stabilized, and the detection accuracy of the position detection means can be further improved. Furthermore, the biasing force applied to the moving element by the biasing member causes the contact portion of the rotation restricting portion to contact the contacted portion and restricts the rotation of the movable member. It is possible to effectively suppress the play of the movable member that reciprocates in the axial direction. Therefore, it is possible to prevent a decrease in position detection accuracy due to the play of the movable member.
As described above, the position detection accuracy of the movable member can be improved with a simple and inexpensive configuration.
In addition, the code | symbol in parenthesis here has shown the code | symbol of the corresponding component of embodiment mentioned later as an example of this invention.

  According to the drive device for a performance operator according to the present invention, it is possible to effectively improve the position detection accuracy of the mover by the position detection means, while having a simple and inexpensive configuration.

1 is a block diagram showing an example of the overall functional configuration of an electronic keyboard instrument including a key driving device according to a first embodiment of the present invention. It is a figure which shows the drive device of the key concerning 1st Embodiment, and is a schematic side view which shows the key and its surrounding component part. (A) is a partial side view which shows a drive device, (b) is a schematic plan view of a position sensor. (A) is a perspective view which shows the structural example of an electrostatic encoder, (b) is a figure which shows a stator, (c) is a figure which shows a moving element. FIGS. 4A and 4B are diagrams for explaining how the phase angle of a vector changes according to the position of a moving element. FIG. 5A shows a case where the moving element is at a position of d = 0, and FIG. A case where the electrode pitch is moved rightward by a distance d = Ps is shown. It is a figure for demonstrating operation | movement of a key and a mass body, (a) is a state which has a key in a non-key-pressing position, (b) is a figure which shows the state in which a key is in a key-pressing position. It is a figure which shows the drive device concerning 2nd Embodiment of this invention, (a) is a partial side view which shows a drive device, (b) is a schematic plan view of a position sensor. It is a figure which shows the drive device concerning 3rd Embodiment of this invention, (a) is a partial side view which shows a drive device, (b) is a schematic plan view of a position sensor. It is a figure which shows the keyboard apparatus provided with the drive device concerning 4th Embodiment of this invention, and is a schematic side view which shows the key and its peripheral component part.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[First Embodiment]
FIG. 1 is a block diagram showing an overall functional configuration of an electronic keyboard instrument provided with a drive device for keys (performance operators) according to the first embodiment of the present invention. The electronic keyboard instrument 1 shown in FIG. 1 includes a keyboard device 10 having a key 20 and a drive device 40 for driving the key 20, a pedal device 52, and the electronic keyboard instrument 1 including the keyboard device 10 and the pedal device 52. And a main control unit 50 for controlling the whole. Each part of the electronic keyboard instrument 1 such as the keyboard device 10, the pedal device 52, and the main control unit 50 is connected to each other via a bus 51.

  The main control unit 50 includes a CPU 51, a ROM 52, a RAM 53, and a flash memory (EEPROM) 54. A timer 55 is connected to the CPU 51. The CPU 51 controls the entire electronic keyboard instrument 1 including the keyboard device 10. In addition to the control program executed by the CPU 51 and various table data, the ROM 52 and the flash memory 54 store a force sense imparting table 80 described later. The RAM 53 temporarily stores various input information such as performance data and text data, various flags, buffer data, and arithmetic processing results. The timer 55 measures various times such as an interrupt time in the timer interrupt process.

  In addition to the main control unit 50, the electronic keyboard instrument 1 includes a setting operation unit 61, a display device 63, an audio output unit 65, an external storage device 66, an HDD 67, a communication interface 68, a MIDI interface 69, and the like. . An external device 71 can be connected to the communication interface 68, and a MIDI device 72 can be connected to the MIDI interface 69. The communication interface 68 can communicate with an external server device 74 via a communication network 73 such as the Internet. The setting operation unit 61 includes various switches (not shown) used by the performer to input setting operation information, and a signal generated by the operation of the switch is supplied to the CPU 51. The external storage device 66 and the HDD 67 store various application programs including the above control program, various music data, and the like. The display device 63 is connected to the bus 51 via the display control circuit 62, and the audio output unit 65 is connected to the bus 51 via the sound source circuit 64.

  2 and 3 are diagrams showing the keyboard device 10, FIG. 2 is a schematic side view of the key 20 and its surroundings, and FIG. 3 is a partially enlarged side view showing a detailed configuration of the driving device 40 and its surroundings. . The keyboard device 10 includes a flat frame 11 that is a part of the electronic keyboard instrument 1, a key 20 and a mass body (pseudo hammer) 30 that are rotatably supported with respect to the frame 11, And a drive device 40 composed of an electromagnetic actuator installed between the mass bodies 30. In the following description, of the two sides of the key 20 in the longitudinal direction, the player side of the electronic keyboard instrument 1 is referred to as the front or the front, and the opposite side is referred to as the back or the rear. In FIG. 2, one key 20 and its peripheral components are shown among the plurality of keys 20 provided in parallel in the keyboard device 10. Moreover, although the case where the key 20 is a white key is shown in the same figure, the configuration is the same in the case of a black key. Although not shown, the keyboard device 10 is also provided with a switch contact mechanism for converting the operation of the key 20 into an electrical output so as to generate a musical sound according to the operation of the key 20. .

  The key 20 is supported by a key fulcrum 12 on the frame 11 at an intermediate position in the front-rear direction. The key fulcrum 12 includes a fulcrum pin 12b erected on a balance rail 12a extending along the arrangement direction of the key 20 on the frame 11, and the key 20 is supported by the fulcrum pin 12b. The front end 20a and the rear end 20b of the key 20 can be rotated in the vertical direction about the key fulcrum 12, and are rotated in response to a key pressing operation to the key pressing portion 20c by the performer. Further, a front pin 13 is erected below the front end 20 a of the key 20. The front pin 13 has an upper end inserted into the back side of the key 20 and restricts lateral deflection of the front end 20a of the rotating key 20.

  A key upper limit stopper 21 is installed below the rear end 20b of the key 20, and a key lower limit stopper 22 is installed below the front end 20a. Each of the key upper limit stopper 21 and the key lower limit stopper 22 includes a cushioning material such as felt fixed to the upper surface of the frame 11. The key upper limit stopper 21 contacts the lower surface of the rear end 20b of the key 20 at the non-key-pressing position (see FIG. 6A), and restricts the rotation of the key 20 at the non-key-pressing position. On the other hand, the key lower limit stopper 22 contacts the lower surface of the front end 20a of the key 20 at the key pressing position (see FIG. 6B), and restricts the rotation of the key 20 at the key pressing position.

  A columnar support portion 14 for supporting the mass body 30 is provided on the frame 11 behind the key fulcrum 12. The support unit 14 protrudes from between adjacent keys 20 on the frame 11 directly above each key 20 at a rate of one for each of a plurality of key ranges. The support portion 14 includes a front wall 14a and a rear wall 14b that are arranged forward and backward at a predetermined interval. Both the front wall 14 a and the rear wall 14 b are vertically erected and extend to a position higher than the key 20.

  The mass body 30 supported by the support portion 14 is installed corresponding to each key 20, and is installed at a position directly above the key fulcrum 12. The mass body 30 includes a straight bar-shaped shank portion 32 extending rearward from a mass body fulcrum 31 provided at the upper end of the front wall 14a of the support portion 14, and a mass portion having a predetermined mass attached to the tip of the shank portion 32 ( Weight) 33. The shank portion 32 is rotatably supported by the mass body fulcrum 31, and is rotated up and down within a vertical plane along the longitudinal direction of the key 20. The mass portion 33 is formed in a rod shape extending along the rotation direction at the tip of the shank portion 32. The mass body 30 is configured such that the mass portion 33 rotates in the vertical direction above the vicinity of the rear end of the key 20 with the shank portion 32 as an arm around the mass body fulcrum 31.

  A mass body upper limit stopper 34 and a mass body lower limit stopper 35 for restricting the rotation of the mass body 30 are provided on the rear wall 14 b of the support portion 14. The mass body lower limit stopper 35 contacts the shank portion 32 of the mass body 30 rotated to the lower limit position, and the mass body upper limit stopper 34 contacts the shank portion 32 of the mass body 30 rotated to the upper limit position. It is something to touch. By these mass body lower limit stopper 35 and mass body upper limit stopper 34, the mass body 30 has a lower limit position (see FIG. 6A) in which the shank portion 32 extends obliquely downward on the rear side from the mass body fulcrum 31, and the shank portion. 32 is controlled to rotate between the mass body fulcrum 31 and an upper limit position (see FIG. 6B) extending in the substantially horizontal direction on the rear side. The mass body 30 is interlocked with the operation of the key 20 via a plunger 46 described later, and gives the key 20 a reaction force to the performance operation in cooperation with the driving device 40.

  A driving device 40 for applying a predetermined driving force to the key 20 and the mass body 30 is installed between the upper surface of the key 20 on the rear side of the key fulcrum 12 and the shank portion 32 of the mass body 30. The drive device 40 of the present embodiment is a bidirectional drive type electromagnetic actuator, and as shown in FIG. 3, a coil (drive source) 41 composed of a forward coil 41a and a backward coil 41b arranged side by side coaxially in the vertical direction. And a plunger (movable member) 46 installed on the inner peripheral side of a cylindrical bobbin (guide portion) 43 around which the coil 41 is wound. The plunger 46 is guided by the bobbin 43 so as to be vertically movable and rotatable. Further, yokes 49a and 49b are provided on the outer circumferences of the forward coil 41a and the backward coil 41b.

  The yokes 49a and 49b are fixed to the front surface of the rear wall 14b of the support portion 14 via the plate 15 whose rear side surface is a flat plate. Therefore, the forward coil 41a and the backward coil 41b are fixed to the support portion 14 and the frame 11 on the fixed side. On the other hand, the plunger 46 has a barrel portion 42a made of a columnar ferromagnetic body that is slidable (reciprocating) in the vertical direction on the inner peripheral surface of the bobbin 43, and a rod-shaped first portion connected to the upper end of the barrel portion 42a. 1 rod 42b and the 2nd rod 42c connected with the lower end. A columnar base member 44 having a horizontal upper surface is attached to the upper end of the first rod 42b. On the other hand, a cap-shaped cover member 45 having a buffering and sliding action is attached to the lower end of the second rod 42c. And the axial center of the trunk | drum 42a, the 1st rod 42b, and the 2nd rod 42c is arranged in the straight line shape toward the perpendicular direction.

  A cylindrical roller 36 is attached to the shank portion 32 of the mass body 30. The roller 36 has an axial direction horizontally oriented along the arrangement direction of the keys 20, and a lower side surface (cylindrical surface) is placed on the upper surface of the base member 44. On the other hand, the cover member 45 at the lower end of the second rod 42 c of the plunger 46 is placed on a screw 25 provided on the upper surface of the opposing key 20. Therefore, the plunger 46 is disposed in a state of being sandwiched between the mass body 30 and the key 20 by a load due to the weight of the mass body 30.

  The drive device 40 is configured to drive the plunger 46 in both directions along the axial direction by supplying a drive current to the forward coil 41a and the backward coil 41b. That is, when a drive current is supplied to the return coil 41b, the plunger 46 moves downward. As a result, a downward load is applied from the plunger 46 to the rear side of the key fulcrum 12 of the key 20, so that the load applied in the key release direction of the key 20 increases. On the other hand, when a drive current is supplied to the forward movement coil 41a, the plunger 46 moves upward. Thereby, since the load applied downward from the plunger 46 to the rear side of the key fulcrum 12 of the key 20 is reduced, the load applied in the key release direction of the key 20 is reduced.

  The drive device 40 is provided with a position sensor (position detection means) 47 for detecting the position of the plunger 46. As shown in FIG. 3, the position sensor 47 is a plate-shaped moving element 110 attached to the plunger 46 and a plate-shaped fixed element installed on the coil 41 side (fixed side) so as to bring the moving element 110 into surface contact. A voltage is applied to the induction electrode 103 (see FIG. 4) of the stator 101, and the potential distribution generated on the movement electrode 112 (see FIG. 4) of the mover 110 by electrostatic induction is applied to the stator 101. This is an electrostatic encoder that detects the position of the mover 110 by detecting it with the potential detection electrode 104 (see FIG. 4).

  The principle and configuration of the electrostatic encoder will be described. The basic principle and detailed configuration of the electrostatic encoder are disclosed in Japanese Patent Laid-Open No. 2005-221472. 4A is a diagram illustrating a configuration example of an electrostatic encoder, FIG. 4B is a diagram illustrating a stator 101 provided in the electrostatic encoder, and FIG. 4C is a diagram illustrating a movable element 110. FIG. The electrostatic encoder is divided into a sensor unit including a stator 101, a mover 110 capable of reciprocating in a surface contact state with the stator 101, and a peripheral circuit including other electric circuits. . Then, the output of the AC transmitter 121 is amplified to an appropriate size by the amplifier 122 and applied to the terminals U and V of the stator 101 as a differential output of the carrier wave. The signals obtained at the terminals A and C of the stator 101 are received by the differential amplifier 123a, and the signals obtained at the terminals B and D are received by the differential amplifier 123b, and the subsequent multipliers 124a and 124b A carrier wave component is removed by a synchronous detection circuit including low-pass filters 125a and 125b, and complex number components “REAL” and “IMAG” including two baseband signals are extracted. These two differential amplifiers 123a and 123b, multipliers 124a and 124b, and low-pass filters 125a and 125b constitute a vector generation circuit 120 as a whole. Then, the phase division circuit 126 performs a multiplication process, and outputs two increment signals of an A-phase pulse and a B-phase pulse corresponding to the moving distance.

  A stator 101 shown in FIG. 4B includes induction electrodes 103 a and 103 b and a potential detection electrode 104 incorporated in an insulator 102. A terminal U for inputting a carrier wave is connected to the induction electrode 103a, and the other terminal V is connected to the induction electrode 103b. Such a stator 101 can be manufactured using a printed circuit board or a flexible printed circuit board that is generally used in electronic devices.

  The moving element 110 shown in FIG. 4C is installed so as to contact the surface of the stator 101. The mover 110 has a pair of comb-like electrodes 112 a and 112 b on the electrode surface 112 disposed in an insulator 111 in a crossed finger shape, and the bases of the comb-like electrodes 112 a and 112 b serve as induction electrodes of the stator 101. 103a and 103b are arranged so as to overlap. The moving element 110 is supplied with electric energy by electrostatic induction via the induction electrodes 103a and 103b of the stator 101 without any connection to the outside. Therefore, as in this embodiment, if the mover 110 is attached to the plunger 46 that is the object to be measured, the plunger 46 can be freely moved without restrictions such as routing of the signal line, and the plunger 46 can be smoothly moved. The operation can be secured.

  Then, a plus is applied to the induction electrode 103a of the stator 101 and a minus is applied to the induction electrode 103b by an external power source (not shown). At this time, due to the principle of electrostatic induction, a negative true charge is induced at the base of one comb-like electrode 112a of the movable element 110, and a positive true charge is generated at the comb-teeth end of the comb-like electrode 112a. A charge is induced. Further, a positive true charge is induced at the base of the other comb-shaped electrode 112b, and a negative true charge is induced at the end of the comb tooth. In the vicinity of the center where the comb teeth ends of the two comb-shaped electrodes 112a and 112b face each other, the electrodes are insulated and close to each other, so that positive and negative charges are attracted to each other, and the comb teeth surface has a certain amount. True charge is distributed at a uniform density. As described above, the alternating potential distribution in which positive and negative true charges are alternately distributed in the vicinity of the central portion of the electrode by the two comb-like electrodes 112a and 112b disposed in a crossed finger shape relative to the electrostatic induction described above. It is formed.

  FIGS. 5A and 5B are diagrams for explaining how a vector whose component is a voltage detected by the potential detection electrode 104 changes according to the position of the mover 110. Actually, since it is driven using a carrier wave signal generated from the AC transmitter 121 shown in FIG. 4A, it is necessary to consider a temporal change, but here, for the sake of easy understanding, A state in which the carrier wave signal is cut out in an instant, that is, a direct-current signal without time change will be described.

  FIG. 5A shows a case where the mover 110 is at the position of d = 0. The potential detection electrode 104 has a four-phase electrode arrangement. An electrode having a 0 degree phase is connected to the terminal A, an electrode having a 90 degree phase is connected to the terminal B, an electrode having a 180 degree phase is connected to the terminal C, and an electrode having a 270 degree phase is provided. Each is connected to a terminal D. When an external voltage is applied to the induction electrodes 103a and 103b of the stator 101, "-", "++", "-", and "++" are applied to the comb-tooth electrodes 112a and 112b of the movable element 110 by electrostatic induction. True charge is generated, and an alternating potential distribution 151 is formed. Then, under the influence of this alternating potential distribution 151, “+”, “0”, “−”, “0” charges are repeatedly induced in the potential detection electrode 104 of the stator 101, and the terminal A is induced. A voltage of +, zero is generated at the terminal B, − is generated at the terminal C, and zero is generated at the terminal D. Then, a positive voltage is generated in the differential amplifier 123a, and the output of the differential amplifier 123b becomes zero. If the output of the differential amplifier 123a is represented in complex space as a complex real component “REAL” and the output of the differential amplifier 123b is represented as a complex imaginary component “IMAG”, a vector having only the “REAL” component is obtained.

  FIG. 5B shows a case where the mover 110 has moved to the right by the pitch distance d = Ps of the potential detection electrode 104. At this time, the potential detection electrode 104 has “0” and “+”. , “0”, and “−” are repeatedly induced, and a zero voltage is generated at the terminal A, a positive voltage is generated at the terminal B, a zero voltage is generated at the terminal C, and a negative voltage is generated at the terminal D. Then, the output of the differential amplifier 123a is zero, and a positive voltage is generated at the output of the differential amplifier 123b. In the complex space, a vector having only the “IMAG” component is obtained.

  In this way, the vector angle in the complex space changes according to the position of the mover 110. Each time the mover 110 moves at the pitch Ps interval of the potential detection electrode 104, the vector rotates by 90 degrees and returns to the original position at the moving distance d = 4Ps. Therefore, by detecting the vector angle in the complex space, it is possible to detect where the moving element 110 is. If the movement is less than the pitch, for example, if the movement distance is d = Ps / 8, the phase change amount of the vector is 11.25 degrees, and the fine movement change amount is accurately reflected in the vector phase.

  In the electrostatic encoder having the above configuration, as shown in FIGS. 5A and 5B, a plurality of alternating potential distributions 151 generated in the comb-like electrodes 112a and 112b of the mover 110 are arranged in the stator 101. Since detection is performed by the potential detection electrode 104, a desired voltage is detected even if the comb-shaped electrodes 112a and 112b and the potential detection electrode 104 are not necessarily in parallel. For this reason, the positioning of the stator 101 and the mover 110 may be approximate, and strict alignment is not necessary. Note that the stator 101 and the mover 110 do not necessarily need to be in contact with each other, and may be slightly separated as long as a signal can be detected.

  In the position sensor 47 of the present embodiment, as shown in FIG. 3, the mover 110 is a flexible thin plate member made of a synthetic resin material or the like. The moving element 110 has elasticity against the bending of the surface (returning force to return to the original flat shape when the surface is bent). The moving element 110 has a substantially rectangular outer shape, one side of which is fixed to the side surface of the base member 44, and the other opposite side is a free end. The surface on the free end side is in contact with the surface of the stator 101 in a pressed state with the surface being bent. Thereby, the electrode surface (comb-like electrode) 112 of the mover 110 is in contact with the electrode surface (potential detection electrode) 104 of the stator 101 in a pressed state, and the plunger 46 reciprocates in the axial direction. Along with the movement, the electrode surface 112 of the moving element 110 and the electrode surface 104 of the stator 101 come into sliding contact.

  Further, the plunger 46 is provided with a rotation restricting portion 48 for restricting rotation (autorotation) around the axis. The rotation restricting portion 48 includes a small protrusion-like contact portion 48a provided on the side surface of the base member 44 in the plunger 46 and a columnar contact provided on the upper surface of the coil 41 on the fixed side (the upper surface around the plunger 46). The contact portion 48b of the plunger 46 guided by the bobbin (guide portion) 43 comes into contact with the contacted portion 48b, whereby the rotation of the plunger 46 is regulated. ing. Further, a contacted portion 48c is provided at a position opposite to the contacted portion 48b with the contact portion 48a interposed therebetween. The abutted portion 48c is formed in a columnar shape similar to the abutted portion 48b, and is arranged with a slight gap with respect to the abutting portion 48a abutting on the abutted portion 48b. Yes. In addition, illustration of the to-be-contacted part 48c is abbreviate | omitted in Fig.3 (a).

  Since the movable element 110 of the position sensor 47 is in contact with the stator 101 in a bent state, a biasing force in the rotational direction is generated in the plunger 46 due to a reaction caused by the elastic force of the movable element 110. By this urging force, the contact portion 48a of the rotation restricting portion 48 is normally in contact with (being pressed against) the contacted portion 48b, and the rotation of the plunger 46 is restricted. Further, by providing the abutted portion 48c, even if a strong force that rotates the plunger 46 in the counterclockwise direction in FIG. By contacting the portion 48c, the rotation of the plunger 46 in the same direction is restricted. As a result, it is possible to prevent the mover 110 from being excessively bent and damaged.

  Next, the operation of the keyboard apparatus 10 having the above configuration will be described. 6A and 6B are diagrams for explaining the operation of the keyboard device 10. FIG. 6A shows a state where the key 20 is in a non-key-pressed position, and FIG. 6B shows a state where the key 20 is in a key-pressed position. Show. The key 20 is subjected to a key pressing force by the magnitude relationship between the biasing force in the key pressing direction generated by the mass (self-weight) balance before and after the key fulcrum 12 and the load from the mass body 30 via the plunger 46. In the state where it is not, the lower surface of the rear end 20b is in contact with the key upper limit stopper 21, and the key pressing portion 20c of the front end 20a is raised to the uppermost position, and is in the non-key pressing position shown in FIG. At this time, the mass body 30 is in the lower limit position where the shank portion 32 contacts the mass body lower limit stopper 35. On the other hand, when the key 20 in the non-key pressing position is pressed, the key 20 rotates in the key pressing direction about the key fulcrum 12 while pushing up the mass body 30 via the plunger 46. In this way, the lower surface of the front end 20a is rotated to a position where it contacts the key lower limit stopper 22, and the key pressing position shown in FIG. 6B is obtained. When the key 20 is in the key pressing position, the mass body 30 pushed up by the key 20 via the plunger 46 is at the upper limit position where the shank portion 32 contacts the mass body upper limit stopper 34. When the key pressing force on the key 20 is released, a load is applied to the key 20 from the mass body 30 that rotates downward by its own weight through the plunger 46. The key 20 returns to the non-key-pressed position by both this load and its own weight balance.

  When the operation of the key 20 using the inertial mass of the mass body 30 is performed, the plunger 46 is driven bidirectionally by the driving device 40 to assist the urging force applied to the key 20 from the mass body 30 or Can be reduced. Therefore, by controlling the driving of the driving device 40 by the main control unit 50, it is possible to perform force sense control of the reaction force with respect to the key pressing operation.

  As shown in FIG. 1, the drive control circuit that controls the drive of the key 20 outputs a drive PWM (pulse width modulation) signal to the drive device 40 in response to a command from the main control unit 50. A control driver 58 is provided. The ROM 52 of the main control unit 50 stores a keyboard force sense imparting table 80 in which patterns of driving force to be generated by the driving device 40 are stored. The position information of the key 20 detected by the position sensor 47 is output to the main control unit 50. A control signal from the main control unit 50 is input to the control driver 58. The control driver 58 supplies a driving signal to the driving device 40 based on a control signal from the main control unit 50.

  The drive device 40 of the key 20 of the present embodiment is a movable element 110 having a movable electrode 112 provided on the plunger (movable member) 46 side as a position sensor 47 for detecting the position of the plunger 46, and a fixed side. And a stator 101 having an induction electrode 103 and a potential detection electrode 104 provided on the coil 41. A voltage is applied to the induction electrode 103 of the stator 101, and generated on the moving electrode 112 of the mover 110 by electrostatic induction. An electrostatic sensor configured to detect the position of the mover 110 relative to the stator 101 by detecting the potential distribution with the potential detection electrode 104 of the stator 101 is employed. As described above, the position sensor 47 for detecting the position of the plunger 46 is a small and thin electrostatic encoder with good position detection accuracy. The accuracy can be improved effectively. Further, in the electrostatic encoder, since there is no need to connect wiring to the moving element 110 side, the movement of the plunger 46 to which the moving element 110 is attached is not hindered, and the smooth operation of the driving device 40 can be ensured.

  Further, since the plate-like moving element 110 having elasticity against the bending of the surface is provided and pressed against the stator 101 in a state where the moving element 110 is bent, it is fixed to the electrode surface 112 of the moving element 110. The electrode surface 104 of the child 101 can be reliably brought into contact. Therefore, the position detection accuracy of the plunger 46 by the electrostatic encoder can be further improved. In addition, since the elastic plate-like moving element 110 is in contact with the stator 101 in a bent state, a biasing force in the rotation direction is generated in the plunger 46, and the rotation restricting portion is generated by the biasing force. The 48 abutting portions 48 a abut against the abutted portion 48 b so that the rotation of the plunger 46 is restricted. As a result, it is possible to effectively suppress the play of the plunger 46 that is guided by the bobbin (guide portion) 43 and reciprocates in the axial direction. Accordingly, it is possible to prevent a decrease in position detection accuracy due to the play of the plunger 46. As described above, it is possible to improve the position detection accuracy of the plunger 46 with a simple and inexpensive configuration.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the description of the second embodiment and the corresponding drawings, the same or corresponding components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted below. In addition, matters other than those described below are the same as those in the first embodiment. These points are the same for the other embodiments.

  7A and 7B are diagrams showing a driving device 40-2 according to the second embodiment of the present invention, in which FIG. 7A is a schematic side view showing the whole driving device 40-2, and FIG. 7B is a position sensor 47-. FIG. In addition to the configuration of the driving device 40 of the first embodiment, the driving device 40-2 of the present embodiment biases the electrode surface 112 of the movable element 110 against the electrode surface 104 of the stator 101. It has. Further, the drive device 40 of the first embodiment is a bidirectional drive type electromagnetic actuator, whereas the drive device 40-2 of the present embodiment is a unidirectional drive type electromagnetic actuator. . Except for these points, the other configuration is the same as that of the driving device 40 of the first embodiment.

  That is, the urging member 37 included in the driving device 40-2 is a sheet-like member made of felt or nonwoven fabric. The urging member 37 is attached to the rear side surface of the support column 37 a erected on the upper end surface of the coil 41, and presses the mover 110 that contacts the front surface of the stator 101 toward the stator 101 from the front side. It is installed in a state.

  Further, the driving device 40-2 moves the plunger 46 only downward (key 20 side) by driving a single coil 41. Therefore, although not shown, the drive control circuit included in the keyboard device 10-2 of the present embodiment has a configuration necessary for controlling the drive of the drive device 40-2 including the single coil 41. Yes.

  In the driving device 40-2 according to the present embodiment, the electrode surface 112 of the moving element 110 can be uniformly brought into contact with the electrode surface 104 of the stator 101 by urging by the urging member 37. The clearances 112 and 104 can be stabilized. Therefore, the position detection accuracy of the plunger 46 by the position sensor 47-2 can be further improved. Further, since the mover 110 moves while being sandwiched between the stator 101 and the urging member 37, the operation of the plunger 46 is further stabilized, and the position detection accuracy is also improved in this respect.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIGS. 8A and 8B are diagrams showing a drive device 40-3 according to the third embodiment of the present invention, in which FIG. 8A is a schematic side view showing the entire drive device 40-3, and FIG. 8B is a drive device 40-. 3 is a schematic plan view of a position sensor 47-3 included in FIG. In FIG. 8A, illustration of other members adjacent to the driving device 40-3 such as the shank portion 32 and the key 20 of the mass body 30 is omitted. The drive device 40-3 of the present embodiment is in contact with the stator 101 in a state where the plate-like moving element 110 attached to the plunger 46 is not bent so that one end is a free end. In addition, a biasing member 37 that biases the electrode surface 112 of the mover 110 against the electrode surface 104 of the stator 101 is provided.

  That is, the movable element 110 protruding from the side surface of the base member 44 has a flat surface. The electrode surface 112 of the mover 110 is pressed against the electrode surface 104 of the stator 101 by the urging by the urging member 37. The urging member 37 has the same configuration as in the second embodiment. Therefore, in this embodiment, the mover 110 does not necessarily have flexibility and elasticity, and may be a flat plate member made of a hard material. The moving member 110 is urged against the stator 101 by the urging member 37, so that the abutting portion 48a of the rotation restricting portion 48 abuts on the abutted portion 48b and the rotation of the plunger 46 is restricted. It is in a state.

  In the driving device 40 of the first embodiment, the reciprocating motion of the plunger 46 is guided by the cylindrical bobbin 43, whereas the driving device 40-3 of the present embodiment is replaced with the bobbin 43. A first bearing 38 a and a second bearing 38 b for guiding the plunger 46 above and below the coil 41 are provided. The first bearing 38a is installed so as to support the outer periphery of the plunger 46 near the upper end of the first rod 42b, and the second bearing 38b supports the outer periphery of the plunger 46 near the lower end of the second rod 42c. Is installed. The first bearing 38a and the second bearing 38b are provided with slight gaps (clearances) A and A ′ with respect to the outer circumferences of the first rod 42b and the second rod 42c in order to ensure a smooth operation of the plunger 46. Have.

  In the keyboard device 10, although detailed illustration is omitted, in order to accommodate the driving device 40-3 in the lateral space of the key 20, the driving device 40-3 that drives the adjacent key 20 is shifted alternately up and down. Arrangement is done. In this case, since the interval between the first bearing 38a and the second bearing 38b disposed at both ends of the plunger 46 with the coil 41 interposed therebetween must ensure at least the size of the two coils 41 arranged vertically, The said space | interval will become large. Then, as the distance between the first bearing 38a and the second bearing 38b becomes longer, the dimensions of the clearances A and A ′ in the first bearing 38a and the second bearing 38b are set larger in order to allow the operation with respect to the inclination of the plunger 46. There is a need. However, when the clearances A and A 'are set to be large, there is a problem that the plunger 46 is likely to be loose.

  On the other hand, in the drive device 40-3 of the present embodiment, the moving element 110 of the position sensor 47-3 is urged by the urging member 37, so that the rotation restricting portion 48 is abutted by the urging force. 48a abuts against the abutted portion 48b so that the rotation and backlash of the plunger 46 are restricted. Accordingly, even when the gaps A and A ′ between the first bearing 38a and the second bearing 38b are large, the plunger 46 that is guided by the first bearing 38a and the second bearing 38b and reciprocates in the axial direction can be operated smoothly. It can be secured. Therefore, it is possible to prevent a decrease in detection accuracy of the position sensor 47 due to the play of the plunger 46.

  Also in the driving device 40-3 of this embodiment, the electrode surface 112 of the mover 110 can be uniformly brought into contact with the electrode surface 104 of the stator 101 by the biasing member 37. 104 can be stabilized, and the position detection accuracy by the position sensor 47-3 can be improved. In addition, in the drive device 40-3 of this embodiment, although the case where the position sensor 47-3 provided with the flat-shaped moving element 110-3 which was not bent was demonstrated, it replaced with this and the state bent It is also possible to install the position sensor 47 of the first embodiment provided with the mover 110 installed in step 1 or the position sensor 47-2 of the second embodiment.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. FIG. 9 is a diagram conceptually showing the configuration of the keyboard apparatus 10-4 according to the fourth embodiment. Compared with the keyboard device 10 of the first embodiment, the keyboard device 10-4 of the present embodiment has a reverse relationship in the arrangement of the key 20 and the mass body 30, and accordingly, the key 20 and the mass body 30. The direction of the driving device 40-4 installed between the two is also reversed upside down. Moreover, the direction of operation | movement of each of the key 20, the mass body 30, and the drive device 40-4 is also reverse with respect to 1st Embodiment.

  That is, in the keyboard device 10-4 of the present embodiment, the mass body 30 is installed below the key 20, and the driving device 40-4 and the plunger 46 are disposed between the lower surface of the key 20 and the mass body 30. Has been. In the plunger 46, the upper end of the second rod 42c extending upward is in contact with the lower surface of the key 20 on the front side of the key fulcrum 12, and the lower end of the base member 44 fixed to the first rod 42b extending downward is the mass. The body fulcrum 31 is in contact with the upper surface of the shank part 32 extending to the opposite side of the mass part 33. The configurations of the drive device 40-4 and the position sensor 47-4 are the same as those of the drive device 40 and the position sensor 47 of the first embodiment except that the top and bottom are reversed.

  Also in the keyboard device 10-4 of the present embodiment, the key 20 is not pressed by both the weight balance before and after the key fulcrum 12 and the load from the mass body 30 via the plunger 46. In the state, as shown in FIG. 9, the lower surface of the rear end 20 b is in a non-key-pressing position where it abuts against the key upper limit stopper 21. At this time, the mass body 30 is in the lower limit position in contact with the mass body lower limit stopper 35. When the key pressing operation is performed, the key 20 rotates while pushing down the shank portion 32 of the mass body 30 via the plunger 46. Thus, the key 20 becomes a key pressing position where the lower surface of the front end 20a abuts against the key lower limit stopper 22. The mass body 30 rotated by being pushed down by the key 20 via the plunger 46 comes into contact with the mass body upper limit stopper 34 and reaches the upper limit position when the key 20 is in the key depression position. On the other hand, when the key pressing force that pushes down the key 20 is released, a load is applied to the key 20 from the rotating mass body 30 via the plunger 46. The key 20 returns to the non-key-pressed position with both this load and its own weight balance.

  Even in the driving device 40-4 according to the present embodiment, the electrostatic sensor including the mover 110 and the stator 101 is used as the position sensor 47 that detects the position of the plunger 46, so that the configuration is simple and inexpensive. The position detection accuracy of the plunger 46 can be improved. In addition, since the position sensor 47 is configured to be pressed against the stator 101 with the mover 110 being bent, the electrode surface 112 of the mover 110 and the electrode surface 104 of the stator 101 can be reliably brought into contact with each other. Further, the position detection accuracy of the plunger 46 by the position sensor 47 can be further improved. Further, rattling of the plunger 46 can be suppressed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. For example, in each of the above embodiments, the case where the performance operator driven by the driving devices 40 to 40-4 is the key 20 is shown. However, the performance operator driven by the driving device according to the present invention is the key. However, other performance operators such as a pedal may be used. In addition, the position sensor according to the present invention detects the position of a member other than the plunger as long as it detects the position of a movable member supported so as to be able to reciprocate in the axial direction of the driving device and to be rotatable about the axis. You may do.

DESCRIPTION OF SYMBOLS 1 Electronic keyboard instrument 10 Keyboard apparatus 20 Key 30 Mass body 38a 1st bearing (guide part)
38b Second bearing (guide part)
40 Drive device 41 Coil (drive source)
41a Forward coil 41b Reverse coil 43 Bobbin (guide part)
46 Plunger (movable member)
47 Position sensor (position detection means)
48 Rotation restriction part 48a Contact part 48b Contacted part 50 Main control part 52 Pedal device 101 Stator 103 (103a, 103b) Induction electrode 104 Potential detection electrode (electrode surface)
110 Mover 112 (112a, 112b) Comb-like electrode (moving electrode, electrode surface)

Claims (3)

A movable member for applying a driving force to the performance operator;
A guide portion that supports the movable member so as to be capable of reciprocating in the axial direction and rotatable about the axis;
A rotation restricting portion that restricts the rotation of the movable member by abutting a contact portion provided on the movable member with a contacted portion provided on the fixed side;
A drive source for driving the movable member;
Position detecting means for detecting the position of the movable member,
The position detecting means includes a moving element having a moving electrode provided on the movable member side, and a stator having an induction electrode and a potential detecting electrode provided on the fixed side, and applies a voltage to the induction electrode of the stator. And detecting the position of the moving element relative to the stator by detecting the potential distribution generated in the moving electrode by electrostatic induction with the potential detecting electrode,
The moving element of the position detecting means is plate-like and has elasticity against surface deflection, and is attached to the movable member so that one end is a free end,
Since the movable element is in contact with the stator in a bent state, an urging force in the rotational direction is generated on the movable member, and the urging force causes the abutting portion of the rotation restricting portion to be in the covered state. A drive device for a performance operator, which is in contact with a contact portion. 2. The drive device for a performance operator according to claim 1, further comprising a biasing member that biases the electrode surface of the movable element against the electrode surface of the stator. A movable member for applying a driving force to the performance operator;
A guide portion that supports the movable member so as to be capable of reciprocating in the axial direction and rotatable about the axis;
A rotation restricting portion that restricts the rotation of the movable member by abutting a contact portion provided on the movable member with a contacted portion provided on the fixed side;
A drive source for driving the movable member;
Position detecting means for detecting the position of the movable member,
The position detecting means includes a moving element having a moving electrode provided on the movable member side, and a stator having an induction electrode and a potential detecting electrode provided on the fixed side, and applies a voltage to the induction electrode of the stator. And detecting the position of the moving element relative to the stator by detecting the potential distribution generated in the moving electrode by electrostatic induction with the potential detecting electrode,
The moving element of the position detecting means is composed of a plate-like member attached to the movable member so that one end is a free end,
An urging member for urging the electrode surface of the movable element against the electrode surface of the stator;
Since the moving element is urged by the urging member with respect to the stator, the abutting portion of the rotation restricting portion abuts on the abutted portion by the urging force of the urging member . A drive device for a performance operator, characterized in that:

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