Playing operation device

Abstract

To generate a detection signal on which fine movement of a movable member used for a musical performance is reflected with high precision.SOLUTION: A musical performance operation device comprises a movable member which is displaced according to musical performance operation, a detected part which is formed of a magnetic body or conductor, and installed at the movable member, and a signal generation unit which generates a detection signal from a reference signal with a low-pass filter using a coil, the filter varying in frequency response with the distance between the detected part and the coil. A high-pass filter includes an input terminal supplied with the reference signal, an output terminal outputting the detection signal, a first capacitive element connected between the input terminal and a connection point, a second capacitive element connected between the connection point and the output terminal, and coils including a first coil connected to the connection point and a second coil connected to the output terminal. A magnetic field generated by the first coil and a magnetic field generated by the second coil are in mutually opposite directions.SELECTED DRAWING: Figure 15

Description

Technical Field

[0005]

[0001] This disclosure relates to a performance operation device used for performance.

Background Art

[0002] For example, various techniques for detecting the displacement of a movable member such as a key in a keyboard instrument have been conventionally proposed. Patent Document 1 discloses a configuration for detecting the position of each key by using a coil installed on the frame of a keyboard instrument and a metal plate installed on each key. In the above configuration, when the metal plate is displaced by pressing a key, the current flowing through the coil changes. By detecting the current flowing through the coil, a detection signal representing the presence or absence of pressing the key is generated.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the technique of Patent Document 1, it is not actually easy to sufficiently change the current of the coil due to the displacement of the metal plate by pressing the key. Therefore, it is difficult to generate a detection signal that accurately reflects the minute displacement of the key. In view of the above circumstances, one aspect of this disclosure aims to generate a detection signal that accurately reflects the minute displacement of a movable member used for performance. [[ID=​​​​To solve the above problems, a performance control device according to one aspect of the present disclosure comprises a movable member that is displaced in accordance with a performance operation, a detected unit made of a magnetic material or a conductor and installed on the movable member, and a signal generating unit that generates a detection signal from a reference signal using a coil-based filter, wherein the frequency response of the filter changes according to the distance between the detected unit and the coil. [Brief explanation of the drawing]

[0006] [Figure 1] This is a block diagram illustrating the configuration of a keyboard instrument in the first embodiment. [Figure 2] This is a block diagram illustrating the configuration of a keyboard instrument. [Figure 3] This is the circuit diagram for the signal generation section. [Figure 4] This is a block diagram illustrating the configuration of a signal processing circuit. [Figure 5] This is the frequency response of the signal generation section. [Figure 6] This is a plan view of the coil. [Figure 7] This is a cross-sectional view of line aa in Figure 6. [Figure 8] This is a circuit diagram of the signal generation unit in the second embodiment. [Figure 9] This is a circuit diagram of the signal generation unit in the third embodiment. [Figure 10] This is the frequency response of the signal generation unit in the third embodiment. [Figure 11] This is a circuit diagram of the signal generation unit in the fourth embodiment. [Figure 12] This is the frequency response of the signal generation unit in the fourth embodiment. [Figure 13] This is a circuit diagram of the signal generation unit in the fifth embodiment. [Figure 14] This is the frequency response of the signal generation unit in the fifth embodiment. [Figure 15] This is a circuit diagram of the signal generation unit in the sixth embodiment. [Figure 16] This is the frequency response of the signal generation unit in the sixth embodiment. [Figure 17] This is a block diagram illustrating the configuration of a keyboard instrument in a modified example. [Figure 18] This is a block diagram illustrating the configuration of a keyboard instrument in a modified example. [Figure 19] This is a plan view illustrating the coil configuration in a modified example. [Figure 20] This is a diagram showing the configuration of a keyboard instrument in a modified example. [Figure 21] This is a diagram showing the configuration of a keyboard instrument in a modified example. [Modes for carrying out the invention]

[0007] A: First Embodiment Figure 1 is a block diagram illustrating the configuration of a keyboard instrument 100 according to the first embodiment of this disclosure. The keyboard instrument 100 is an electronic musical instrument comprising a keyboard 10, a detection system 20, an information processing device 30, and a sound emission device 40. The keyboard 10 is composed of a plurality of keys 12, including white keys and black keys. Each of the plurality of keys 12 is a movable member that displaces in accordance with the playing action of the user. The detection system 20 detects the displacement of each key 12. The information processing device 30 generates an acoustic signal V according to the result of the detection by the detection system 20. The acoustic signal V is a signal representing a musical tone of a pitch corresponding to the key 12 operated by the user. The sound emission device 40 emits the sound represented by the acoustic signal V. For example, a speaker or headphones are used as the sound emission device 40.

[0008] FIG. 2 is a block diagram illustrating a specific configuration of a keyboard instrument 100 focusing on one key 12 of a keyboard 10. The keyboard instrument 100 includes a support member 14. The support member 14 is a structure (frame) that supports each element of the keyboard instrument 100. The support member 14 includes a first surface 141 and a second surface 142. The first surface 141 is a surface facing the keyboard 10. The second surface 142 is a surface on the opposite side of the first surface 141. Each key 12 of the keyboard 10 is supported by the support member 14 with a support portion 13 installed on the first surface 141 as a fulcrum. An elastic body 15 is installed between the bottom surface of the key 12 and the first surface 141 of the support member 14. The elastic body 15 biases the key 12 upward in the vertical direction. An end portion 121 of each key 12 is displaced in the vertical direction by a key press and a key release by a user.

[0009] A connecting member 123 is installed on the bottom surface of the key 12. The connecting member 123 is a portion that protrudes downward in the vertical direction from the bottom surface of the key 12. The connecting member 123 penetrates a through hole 143 formed in the support member 14. That is, the connecting member 123 protrudes downward in the vertical direction from the second surface 142 of the support member 14. Further, a support portion 144 is installed on the second surface 142 of the support member 14. The support portion 144 protrudes downward in the vertical direction from the second surface 142.

[0010] A tuning weight 50 is installed for each key 12 in a space on the opposite side of the key 12 across the support member 14. The tuning weight 50 is a hammer weight for adjusting the operating feeling of the key 12 by a user. The tuning weight 50 is formed of a magnetic body (ferromagnetic body) or a conductor. Specifically, the tuning weight 50 is formed of a magnetic material such as iron or ferrite, for example.

[0011] The adjustment weight 50 is a structure in which a rotating part 51 and a load part 52 are integrally formed. The rotating part 51 is a columnar (for example, cylindrical or prismatic) part extending between a first end e1 and a second end e2. The load part 52 is a weight-shaped part formed with a predetermined weight and is installed at the first end e1 of the rotating part 51. The second end e2 is supported by the connecting member 123. The adjustment weight 50 is rotatably supported by the support part 144 between the first end e1 and the second end e2. With the above configuration, the adjustment weight 50 rotates about the support part 144 as a fulcrum in response to the displacement of the key 12. That is, the position of the load part 52 in the vertical direction changes in conjunction with the displacement of the key 12. Specifically, the load part 52 moves upward in the vertical direction by pressing the key and moves downward in the vertical direction by releasing the key. By moving the load part 52 in conjunction with the displacement of the key 12 as described above, the user perceives an appropriate sense of resistance when pressing the key.

[0012] For each of the plurality of keys 12, the detection system 20 generates a detection signal D at a level corresponding to the position Z of the end 121 in the vertical direction. The position Z is the amount of displacement of the end 121 based on the position of the end 121 in a state where no load acts on the key 12.

[0013] The detection system 20 includes a signal generation unit 60 and a signal processing circuit 21. The signal generation unit 60 is installed for each key 12 on the second surface 142 of the support member 14. The signal generation unit 60 includes a coil 61. The signal generation unit 60 and the load part 52 of the adjustment weight 50 face each other with a gap in the vertical direction. The distance between the signal generation unit 60 and the load part 52 (the distance between the coil 61 and the load part 52) changes according to the position Z of the end 121 in the key 12.

[0014] Figure 3 is a circuit diagram illustrating the electrical configuration of the signal generation unit 60. The signal generation unit 60 is a filter that includes an input terminal T1, an output terminal T2, a coil 61, and a capacitive element 62. The coil 61 is connected between the input terminal T1 and the output terminal T2. The capacitive element 62 is connected between the output terminal T2 and the ground wire. The signal generation unit 60 is a low-pass filter (LPF) that suppresses bandwidth components above the cutoff frequency Fc in the signal supplied to the input terminal T1. The cutoff frequency Fc is set to a value (Fc = 1 / (2π√LC)) corresponding to the inductance coefficient L of the coil 61 and the capacitance coefficient C of the capacitive element 62.

[0015] The signal processing circuit 21 in Figure 2 generates a detection signal D with a level corresponding to the distance between the coil 61 and the load unit 52. Figure 4 is a block diagram illustrating the specific configuration of the signal processing circuit 21. The signal processing circuit 21 comprises a supply circuit 22 and an output circuit 23. The supply circuit 22 supplies a reference signal Q to each of the multiple signal generation units 60. The reference signal Q is a voltage signal whose level fluctuates with frequency Fref. For example, a periodic signal of any waveform, such as a sine wave, can be used as the reference signal Q. The frequency Fref of the reference signal Q is, for example, about 1 MHz. The supply circuit 22 supplies the reference signal Q to each of the multiple signal generation units 60 in a time-division manner. Specifically, the supply circuit 22 is a demultiplexer that sequentially selects each of the multiple signal generation units 60 and supplies the reference signal Q to the selected signal generation unit 60. That is, the reference signal Q is supplied to each of the multiple signal generation units 60 in a time-division manner. Furthermore, the period of the reference signal Q is sufficiently shorter than the time duration for which the supply circuit 22 selects one signal generation unit 60.

[0016] As illustrated in Figure 3, the reference signal Q is supplied to the input terminal T1 of the signal generation unit 60. The signal generation unit 60 generates a detection signal d from the reference signal Q using a filter with a coil 61. The detection signal d is a periodic signal whose level fluctuates with the same period as the reference signal Q.

[0017] Figure 5 shows the frequency responses X(X1,X2) of the signal generation unit 60. Frequency response X1 is the frequency response X of the signal generation unit 60 when the load unit 52 is closest to the coil 61 (hereinafter referred to as the "close state"). On the other hand, frequency response X2 is the frequency response X of the signal generation unit 60 when the load unit 52 is furthest from the coil 61 (hereinafter referred to as the "farthest state").

[0018] The closer the load unit 52 gets to the coil 61, the lower the induction coefficient L of the coil 61 becomes. Therefore, the frequency response X of the signal generation unit 60 changes depending on the distance between the load unit 52 and the coil 61. Specifically, the cutoff frequency Fc in the frequency response X changes depending on the distance between the load unit 52 and the coil 61. For example, the closer the load unit 52 gets to the coil 61, the higher the cutoff frequency Fc becomes. Therefore, the gain G of the reference signal Q with respect to frequency Fref changes depending on the distance between the load unit 52 and the coil 61. For example, in the close-proximity state, the gain G with respect to frequency Fref is a value g1, while in the far-proximity state, the gain G with respect to frequency Fref is a value g2, which is lower than g1.

[0019] As can be understood from the above explanation, a detection signal d with an amplitude level δ corresponding to the distance between the load unit 52 and the coil 61 is output from the output terminal T2 of the signal generation unit 60. In other words, the load unit 52 is used as the detected unit to be detected by the detection system 20.

[0020] In Figure 5, frequency band B is the frequency band above the cutoff frequency Fc in which the gain G changes with frequency. The frequency Fref of the reference signal Q lies within the range W between frequencies fL and fH. Frequency fL is the lower limit of frequency band B in the separated frequency response X2 and corresponds to the cutoff frequency Fc in frequency response X2. Frequency fH is the upper limit of frequency band B in the close-proximity frequency response X1 and corresponds to the frequency in frequency response X1 in which the gain G becomes 0.

[0021] For example, the frequency Fref of the reference signal Q, the induction coefficient L of the coil 61, and the capacitance coefficient C of the capacitive element 62 are set such that the frequency Fref of the reference signal Q is contained within the frequency band B in both the approaching and separating states. That is, the frequency Fref of the reference signal Q is located within the range wM in which the frequency band B in frequency response X1 and the frequency band B in frequency response X2 overlap within the range W. However, configurations in which the frequency Fref is located within the range wL in which the gain G is constant (G=1) in frequency response X1, or configurations in which the frequency Fref is located within the range wH in which the gain G is constant (G=0) in frequency response X2, are also conceivable.

[0022] The output circuit 23 in Figure 4 generates a detection signal D by arranging the detection signals d output sequentially from each of the multiple signal generation units 60 on the time axis. That is, the detection signal D is a voltage signal with an amplitude level δ corresponding to the distance between the load unit 52 and the coil 61 at each key 12. As mentioned above, the distance between the load unit 52 and the coil 61 is linked to the position Z of each key 12, so the detection signal D can be expressed as a signal corresponding to the position Z of each of the multiple keys 12. The detection signal D generated by the output circuit 23 is supplied to the information processing device 30.

[0023] The information processing device 30 in Figure 2 analyzes the position Z of each key 12 by analyzing the detection signal D supplied from the signal processing circuit 21. The information processing device 30 is realized as a computer system comprising a control device 31, a storage device 32, an A / D converter 33, and a sound source circuit 34. The A / D converter 33 converts the detection signal D supplied from the signal processing circuit 21 from analog to digital.

[0024] The control device 31 consists of one or more processors that control each element of the keyboard instrument 100. For example, the control device 31 consists of one or more types of processors such as a CPU (Central Processing Unit), SPU (Sound Processing Unit), DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), or ASIC (Application Specific Integrated Circuit).

[0025] The storage device 32 is one or more memories that store programs executed by the control device 31 and data used by the control device 31. The storage device 32 is composed of known recording media such as magnetic recording media or semiconductor recording media. The storage device 32 may be composed of a combination of multiple types of recording media. Alternatively, a portable recording media that can be attached to or detached from the keyboard instrument 100, or an external recording media that the keyboard instrument 100 can communicate with (e.g., online storage), may be used as the storage device 32.

[0026] The control device 31 analyzes the position Z of each key 12 by analyzing the detection signal D after conversion by the A / D converter 33. The control device 31 also instructs the sound source circuit 34 to produce a musical tone corresponding to the position Z of each key 12. The sound source circuit 34 generates an acoustic signal V representing the musical tone instructed by the control device 31. That is, the sound source circuit 34 generates an acoustic signal V corresponding to the amplitude level δ of the detection signal D. For example, the volume of the acoustic signal V is controlled according to the amplitude level δ. When the acoustic signal V is supplied from the sound source circuit 34 to the sound emission device 40, musical tones corresponding to the user's playing action (pressing or releasing each key 12) are emitted from the sound emission device 40.

[0027] Figure 6 is a plan view illustrating the configuration of the coil 61 in the signal generation unit 60, and Figure 7 is a cross-sectional view of line aa in Figure 6. The coil 61 is composed of, for example, a wiring pattern formed on the surface of a wiring board. The coil 61 includes a first portion 611 and a second portion 612. The first portion 611 and the second portion 612 are formed in different regions in a plan view. Specifically, the first portion 611 and the second portion 612 are adjacent to each other along the longitudinal direction of the key 12.

[0028] The first section 611 is a spiral-shaped portion that rotates from the inner circumference end Ea1 to the outer circumference end Ea2. Similarly, the second section 612 is a spiral-shaped portion that rotates from the inner circumference end Eb1 to the outer circumference end Eb2. End Ea2 is connected to the input terminal T1, and end Eb2 is connected to the output terminal T2. Ends Ea1 and Eb1 are also interconnected via a relay wiring 614.

[0029] As can be understood from the above explanation, the direction of the current flowing through the first part 611 and the direction of the current flowing through the second part 612 are opposite. Specifically, when a current in direction C1 flows through the first part 611, a current in the opposite direction C2 flows through the second part 612. Therefore, as illustrated in Figure 7, magnetic fields are generated in opposite directions in the first part 611 and the second part 612. That is, a magnetic field is formed that flows from one part 611 to the other. With this configuration, the diffusion of the magnetic field between each adjacent key 12 is reduced. Therefore, a detection signal D that accurately reflects the position Z of each of the multiple keys 12 is generated.

[0030] The load portion 52 of the adjustment weight 50 faces both the first portion 611 and the second portion 612 of the coil 61. Specifically, the central axis of the first portion 611 and the central axis of the second portion 612 coincide with the load portion 52. With this configuration, the load portion 52 influences both the magnetic field formed by the first portion 611 and the magnetic field formed by the second portion 612. Therefore, the aforementioned effect of being able to detect the detection signal D, which accurately reflects the minute displacement of the key 12, is remarkable.

[0031] As described above, in the first embodiment, the frequency response X of the signal generation unit 60 changes according to the distance between the load unit 52 and the coil 61, so that a detection signal D with an amplitude level δ corresponding to that distance is generated. That is, a detection signal D corresponding to the position Z of each key 12 is generated. In the above configuration, since the amplitude level δ of the detection signal D changes according to the frequency response X of the signal generation unit 60, it is possible to significantly change the level of the detection signal D in response to the displacement of the key 12. Therefore, there is an advantage in that a detection signal D that accurately reflects the minute displacement of each key 12 can be generated.

[0032] In the first embodiment in particular, the distance between the load portion 52 and the coil 61 in the direction of the central axis of the coil 61 changes according to the displacement of the key 12. Therefore, compared to a configuration in which the load portion 52 and the coil 61 move relative to each other in a plane perpendicular to the central axis of the coil 61 (i.e., a configuration in which the distance between the load portion 52 and the coil 61 in the direction of the central axis of the coil 61 does not change), it is possible to significantly change the amplitude level δ of the detection signal D with respect to the displacement of each key 12.

[0033] Furthermore, in the first embodiment, the adjustment weight 50 (loading part 52) ​​for adjusting the feel of the key 12 operated by the user is also used as a detected part for detecting the position Z of the key 12. Therefore, compared to a configuration in which a detected part is installed separately from the adjustment weight 50, there is the advantage that the configuration of the keyboard instrument 100 is simplified.

[0034] B: Second Embodiment A second embodiment of this disclosure will now be described. For elements whose function is the same as in the first embodiment in each of the configurations illustrated below, the reference numerals used in the description of the first embodiment will be reused, and detailed descriptions of each will be omitted as appropriate.

[0035] Figure 8 is a circuit diagram illustrating the electrical configuration of the signal generation unit 60 in the second embodiment. The signal generation unit 60 in the second embodiment is a filter including an input terminal T1, an output terminal T2, a coil 61, and a resistor 63. The coil 61 is connected between the input terminal T1 and the output terminal T2. Similar to the example in Figure 6, the coil 61 includes a first part 611 and a second part 612, the current directions of which are opposite to each other. The resistor 63 is connected between the output terminal T2 and the ground wire.

[0036] The signal generation unit 60 is a low-pass filter that suppresses components in the reference signal Q supplied to the input terminal T1 that exceed the cutoff frequency Fc, similar to the first embodiment. The cutoff frequency Fc is set to a value (Fc = R / (2πL)) corresponding to the induction coefficient L of the coil 61 and the electrical resistance R of the resistive element 63. The same effects as in the first embodiment are achieved in the second embodiment as well.

[0037] C: Third Embodiment Figure 9 is a circuit diagram illustrating the electrical configuration of the signal generation unit 60 in the third embodiment. The signal generation unit 60 in the third embodiment is a filter including an input terminal T1, an output terminal T2, a coil 61, and a capacitive element 62. The capacitive element 62 is connected between the input terminal T1 and the output terminal T2. The coil 61 is connected between the output terminal T2 and the ground wire. Similar to the example in Figure 6, the coil 61 includes a first part 611 and a second part 612, the current directions of which are opposite to each other.

[0038] Figure 10 shows the frequency response X(X1,X2) of the signal generation unit 60 in the third embodiment. The frequency response X1 in the approach state and the frequency response X2 in the distance state are shown together in Figure 10. The signal generation unit 60 is a high-pass filter (HPF) that suppresses bandwidth components below the cutoff frequency Fc in the reference signal Q supplied to the input terminal T1. The cutoff frequency Fc is set to a value (Fc = 1 / (2π√LC)) corresponding to the induction coefficient L of the coil 61 and the capacitance coefficient C of the capacitive element 62.

[0039] The cutoff frequency Fc in the frequency response X changes depending on the distance between the load unit 52 and the coil 61. For example, the closer the load unit 52 is to the coil 61, the higher the cutoff frequency Fc of the signal generation unit 60. Therefore, the gain G of the reference signal Q with respect to frequency Fref changes depending on the distance between the load unit 52 and the coil 61. For example, in the close-proximity state, the gain G with respect to frequency Fref is a value g1, while in the separated-proximity state, the gain G with respect to frequency Fref is a value g2, which is greater than g1. Therefore, a detection signal d of amplitude level δ corresponding to the distance between the load unit 52 and the coil 61 is output from the output terminal T2 of the signal generation unit 60. The same effects as in the first embodiment are achieved in the third embodiment as well.

[0040] In Figure 10, frequency band B represents the range where the gain G changes with frequency within the frequency band below the cutoff frequency Fc. The frequency Fref of the reference signal Q lies within the range W between frequencies fL and fH. Frequency fL is the lower limit of frequency band B in the separated frequency response X2, and corresponds to the frequency at which the gain G becomes 0 in frequency response X2. Frequency fH is the upper limit of frequency band B in the close-proximity frequency response X1, and corresponds to the cutoff frequency Fc in frequency response X1.

[0041] For example, the frequency Fref of the reference signal Q, the induction coefficient L of the coil 61, and the capacitance coefficient C of the capacitive element 62 are set such that the frequency Fref of the reference signal Q is contained within the frequency band B in both the approaching and separating states. That is, the frequency Fref of the reference signal Q is located within the range wM of the range W where the frequency band B in frequency response X1 and the frequency band B in frequency response X2 overlap. However, configurations in which the frequency Fref is located within the range wL of the range W where the gain G is constant (G=0) in frequency response X1, or configurations in which the frequency Fref is located within the range wH of the range W where the gain G is constant (G=1) in frequency response X2 are also conceivable.

[0042] D: Fourth Embodiment Figure 11 is a circuit diagram illustrating the electrical configuration of the signal generation unit 60 in the fourth embodiment. The signal generation unit 60 in the fourth embodiment is a filter including an input terminal T1, an output terminal T2, a coil 61, a capacitive element 62, a resistive element 63A, and a resistive element 63B. The resistive element 63A is connected between the input terminal T1 and the output terminal T2. The coil 61, the capacitive element 62, and the resistive element 63B are connected between the output terminal T2 and the ground wire. Similar to the example in Figure 6, the coil 61 includes a first part 611 and a second part 612, the current directions of which are opposite to each other.

[0043] Figure 12 shows the frequency response X(X1,X2) of the signal generation unit 60 in the fourth embodiment. The frequency response X1 in the approach state and the frequency response X2 in the separated state are shown together in Figure 12. The signal generation unit 60 in the fourth embodiment is a band-stop filter (BEF) that suppresses the component of the frequency band (stopband) B in the reference signal Q. Specifically, the signal generation unit 60 is a notch filter with a sufficiently narrow frequency band B.

[0044] The frequency response X of the signal generation unit 60 changes depending on the distance between the load unit 52 and the coil 61. Specifically, the position of the frequency band B on the frequency axis changes according to the distance. For example, the closer the load unit 52 gets to the coil 61, the higher the frequency band B of the signal generation unit 60 moves. Therefore, the gain G of the reference signal Q with respect to frequency Fref changes depending on the distance between the load unit 52 and the coil 61. For example, in the close-up state, the gain G with respect to frequency Fref is a value g1, while in the separated state, the gain G with respect to frequency Fref is a value g2, which is greater than g1. Therefore, similar to the first embodiment, a detection signal d of amplitude level δ corresponding to the distance between the load unit 52 and the coil 61 is output from the output terminal T2 of the signal generation unit 60. Note that the frequency Fref of the reference signal Q, the inductance coefficient L of the coil 61, and the capacitance coefficient C of the capacitive element 62 are set so that the frequency Fref of the reference signal Q is contained within the frequency band b in both the close-up and separated states. Frequency band b is the range within frequency band B where the gain G increases with frequency. Alternatively, frequency band b may be defined as the range where the gain G decreases with frequency. Furthermore, the frequency Fref of the reference signal Q may be set within the range where the gain G is constant in either frequency response X1 or frequency response X2.

[0045] The same effects as in the first embodiment are achieved in the fourth embodiment. A band-stop filter has the characteristic that the gradient of the gain G with respect to frequency is steeper compared to a low-pass filter or a high-pass filter. Therefore, according to the fourth embodiment, it is easier to ensure the amount of change in gain G (and thus the amount of change in amplitude level δ) between the approach state and the separation state compared to the first embodiment. In other words, there is an advantage in that a detection signal D that accurately reflects the minute displacement of each key 12 can be generated.

[0046] E: Fifth Embodiment Figure 13 is a circuit diagram illustrating the electrical configuration of the signal generation unit 60 in the fifth embodiment. The signal generation unit 60 in the fifth embodiment is a low-pass filter including an input terminal T1, an output terminal T2, a coil 61A, a coil 61B, a capacitive element 62A, and a capacitive element 62B. Specifically, the signal generation unit 60 in the fifth embodiment has a configuration in which multiple stages (specifically two stages) of the low-pass filter exemplified in the first embodiment are interconnected.

[0047] Coils 61A and 61B are connected between the input terminal T1 and the output terminal T2. Specifically, coil 61A is connected between the input terminal T1 and connection point N, and coil 61B is connected between connection point N and the output terminal T2. Coil 61A is the first part 611 illustrated in Figure 6, and coil 61B is the second part 612 illustrated in Figure 6. That is, the direction of the current flowing through coil 61A and the direction of the current flowing through coil 61B are opposite to each other. As illustrated above, coils 61A and 61B correspond to a single coil 61 illustrated in the first embodiment. Capacitive element 62A is connected between connection point N and the ground wire, and capacitive element 62B is connected between the output terminal T2 and the ground wire.

[0048] Figure 14 shows the frequency response X(X1,X2) of the signal generation unit 60 in the fifth embodiment. The frequency response X1 in the approach state and the frequency response X2 in the separated state are shown together in Figure 14.

[0049] As can be seen from Figure 14, in the fifth embodiment, in which the signal generation unit 60 is composed of multiple low-pass filters, the gradient of the gain G with respect to frequency is steeper compared to the first embodiment, in which the signal generation unit 60 is composed of a single low-pass filter. Therefore, according to the fifth embodiment, it is easier to ensure the amount of change in gain G ΔG (and thus the amount of change in amplitude level δ) between the approach state and the separation state compared to the first embodiment. With the above configuration, there is an advantage in that a detection signal D that accurately reflects the minute displacement of each key 12 can be generated.

[0050] F: Sixth Embodiment Figure 15 is a circuit diagram illustrating the electrical configuration of the signal generation unit 60 in the sixth embodiment. The signal generation unit 60 in the sixth embodiment is a high-pass filter including an input terminal T1, an output terminal T2, a coil 61A, a coil 61B, a capacitive element 62A, and a capacitive element 62B. Specifically, the signal generation unit 60 in the fifth embodiment is configured by interconnecting multiple stages (specifically two stages) of the high-pass filter exemplified in the third embodiment.

[0051] Capacitive elements 62A and 62B are connected between the input terminal T1 and the output terminal T2. Specifically, capacitive element 62A is connected between the input terminal T1 and connection point N, and capacitive element 62B is connected between connection point N and output terminal T2. Coil 61A is connected between connection point N and the ground wire. Coil 61B is connected between the output terminal T2 and the ground wire. Coil 61A is the first part 611 illustrated in Figure 6, and coil 61B is the second part 612 illustrated in Figure 6. That is, the direction of the current flowing through coil 61A and the direction of the current flowing through coil 61B are opposite to each other. As illustrated above, coil 61A and coil 61B correspond to one coil 61 illustrated in the first embodiment.

[0052] Figure 16 shows the frequency response X(X1,X2) of the signal generation unit 60 in the sixth embodiment. The frequency response X1 in the approach state and the frequency response X2 in the separated state are shown together in Figure 16.

[0053] As can be seen from Figure 16, in the sixth embodiment, in which the signal generation unit 60 is composed of multiple high-pass filters, the gradient of the gain G with respect to frequency is steeper compared to the third embodiment, in which the signal generation unit 60 is composed of a single high-pass filter. Therefore, according to the sixth embodiment, it is easier to ensure the amount of change in gain G ΔG (and consequently the amount of change in amplitude level δ) between the approach state and the separation state compared to the third embodiment. With the above configuration, there is an advantage in that a detection signal D that accurately reflects the minute displacement of each key 12 can be generated.

[0054] In Figures 13 and 15, an example configuration is shown in which the first part 611 is used as coil 61A and the second part 612 is used as coil 61B. However, each of coils 61A and 61B may be composed of a coil 61 that includes the first part 611 and the second part 612.

[0055] G: Variant The following are examples of specific modifications that may be added to each of the embodiments exemplified above. Two or more embodiments may be arbitrarily selected from the following examples and merged as appropriate, provided they do not contradict each other.

[0056] (1) In the embodiments described above, a hammer weight connected to the key 12 via a connecting member 123 was exemplified as the adjustment weight 50, but the adjustment weight 50 is not limited to the above examples. For example, as illustrated in Figure 17, a counterweight directly attached to the key 12 may be used as the adjustment weight 50. The adjustment weight 50 is made of, for example, a magnetic material or a conductor. In the configuration of Figure 17, a signal generation unit 60 is installed on the first surface 141 of the support member 14. The distance between the adjustment weight 50 and the signal generation unit 60 changes according to the position Z of the key 12. Therefore, as in the embodiments described above, a detection signal D corresponding to the position Z of each key 12 is generated by the signal processing circuit 21.

[0057] (2) In each of the above-described embodiments, the adjustment weight 50 for adjusting the feel of each key 12 was also used as a detected part for detecting the position Z of the key 12. However, it is not essential to use elements that constitute the keyboard instrument 100 as a detected part. In other words, a detected part may be installed separately from the elements necessary for the keyboard instrument 100.

[0058] For example, as illustrated in Figure 18, a coil 55 installed on the key 12 may be used as the part to be detected. The coil 55 is installed on the bottom surface of the key 12 so as to face the coil 61 of the signal generation unit 60 installed on the first surface 141 of the support member 14. The coil 55 is made up of, for example, a wiring pattern formed of a magnetic material or conductor on the surface of a wiring board, and constitutes a resonant circuit that resonates through mutual induction with the coil 61.

[0059] Figure 19 is a plan view illustrating the configuration of the coil 55. The coil 55 includes a first part 551 and a second part 552. The first part 551 and the second part 552 are formed in different regions in a plan view. Specifically, the first part 551 and the second part 552 are adjacent to each other along the longitudinal direction of the key 12.

[0060] The first section 551 is a spiral-shaped portion that rotates from the inner circumference end Ec1 to the outer circumference end Ec2. Similarly, the second section 552 is a spiral-shaped portion that rotates from the inner circumference end Ed1 to the outer circumference end Ed2. Ends Ec2 and Ed2 are interconnected. Ends Ec1 and Ed1 are also interconnected via a relay wiring 553.

[0061] In the above configuration, an induced current is generated in coil 55 due to electromagnetic induction caused by the magnetic field generated in coil 61 by the supply of the reference signal Q. Therefore, a magnetic field is generated in coil 55 in a direction that cancels out the change in the magnetic field of coil 61. The magnetic field generated in coil 61 changes according to the distance between coil 55 and coil 61. Therefore, a detection signal d with an amplitude level δ corresponding to the distance between coil 55 and coil 61 is output from the output terminal T2 of the signal generation unit 60. That is, as in each of the above-described configurations, a detection signal D corresponding to the position Z of the key 12 is generated.

[0062] As can be seen from the example in Figure 19, the direction of the current flowing through the first part 551 and the direction of the current flowing through the second part 552 are opposite. Therefore, magnetic fields are generated in opposite directions in the first part 551 and the second part 552. That is, a magnetic field is formed that flows from one part 551 to the other. With this configuration, the diffusion of the magnetic field between each adjacent key 12 is reduced. Therefore, a detection signal D is generated that accurately reflects the position Z of each of the multiple keys 12.

[0063] (3) In the above-described embodiments, an example was given of a configuration for detecting the displacement of the keys 12 of the keyboard instrument 100, but the movable members whose displacement is detected by the detection system 20 are not limited to the keys 12. Specific examples of movable members are given below.

[0064] [Aspect A] Figure 20 is a schematic diagram of a configuration in which the detection system 20 is applied to the string striking mechanism 91 of a keyboard instrument 100. The string striking mechanism 91 is an action mechanism that strikes strings (not shown) in conjunction with the displacement of each key 12 of the keyboard 10, similar to an acoustic piano. Specifically, the string striking mechanism 91 is equipped with a hammer 911 that can strike the strings by rotation, and a transmission mechanism 912 (e.g., a wippen, jack, repetition lever, etc.) that rotates the hammer 911 in conjunction with the displacement of the key 12, for each key 12. In the above configuration, the detection system 20 detects the displacement of the hammer 911. Specifically, a detectable part 54 made of a magnetic material or a conductor is installed on the hammer 911 (e.g., the hammer shank). On the other hand, the signal generating unit 60 is installed on the support member 913. The support member 913 is, for example, a structure that supports the string striking mechanism 91. Alternatively, the detection unit 54 may be installed on a component other than the hammer 911 in the string striking mechanism 91.

[0065] [Pattern B] Figure 21 is a schematic diagram of a configuration in which the detection system 20 is applied to the pedal mechanism 92 of a keyboard instrument 100. The pedal mechanism 92 comprises a pedal 921 operated by the user's foot, a support member 922 that supports the pedal 921, and an elastic body 923 that biases the pedal 921 vertically upward. In this configuration, the detection system 20 detects the displacement of the pedal 921. Specifically, the detected part 54 is installed on the bottom surface of the pedal 921. On the other hand, the signal generation unit 60 is installed on the support member 922 so as to face the detected part 54. Note that the instrument in which the pedal mechanism 92 is used is not limited to the keyboard instrument 100. For example, a pedal mechanism 92 with a similar configuration can be used in any instrument such as a percussion instrument.

[0066] As can be understood from the above examples, the objects of detection by the detection system 20 are comprehensively represented as movable members that are displaced in accordance with playing movements. Movable members include playing controls such as the keys 12 or pedals 921 that are directly operated by the user, as well as structures such as hammers 911 that are displaced in conjunction with operations on the playing controls. However, movable members in this disclosure are not limited to members that are displaced in accordance with playing movements. That is, movable members are comprehensively represented as members that can be displaced regardless of the trigger that causes the displacement.

[0067] (4) In each of the above-described embodiments, the keyboard instrument 100 is shown as having a sound source circuit 34, but in configurations where the keyboard instrument 100 has a sound-producing mechanism such as a string striking mechanism 91, the sound source circuit 34 may be omitted. The detection system 20 is used to record the performance of the keyboard instrument 100.

[0068] As can be understood from the above explanation, this disclosure is also identified as a device (performance control device) that controls musical tones by outputting operation signals corresponding to performance actions to the sound source circuit 34 or sound generation mechanism. In addition to musical instruments (keyboard instrument 100) equipped with a sound source circuit 34 or sound generation mechanism as exemplified in the above embodiments, the concept of a performance control device also includes devices that do not have a sound source circuit 34 or sound generation mechanism (for example, a MIDI controller or the aforementioned pedal mechanism 92). In other words, a performance control device in this disclosure is comprehensively expressed as a device operated by a performer (operator) for the purpose of performance.

[0069] (5) In the embodiments described above, the coil 61 is shown to include a first portion 611 and a second portion 612, but it is not necessary for the coil 61 to be formed of two coils. The coil 61 may be formed of a single coil (for example, only one of the first portion 611 and the second portion 612).

[0070] (6) In each of the above-described embodiments, an example was given in which the sound source circuit 34 generates an acoustic signal V corresponding to the position Z of the key 12. However, the control device 31 may realize the function of the sound source circuit 34 by executing a program (sound source software, for example) stored in the memory device 32. The element that generates the acoustic signal V representing the sound corresponding to the level of the detection signal D (sound source circuit 34 or control device 31) is comprehensively expressed as a "sound control unit".

[0071] (7) In the above-described embodiments, the configuration of the adjustment weight 50 is shown to be made entirely of a magnetic material, but the configuration of the adjustment weight 50 is not limited to the above examples. For example, the adjustment weight 50 may be constructed by placing a detected part made of a magnetic material or a conductive material on a base made of an insulating material such as resin or wood. The detected part may be integrally molded with the base, for example, or it may be fixed to the base with an adhesive or the like.

[0072] (8) In the above-described embodiments, an example was given in which the distance between the coil 61 and the detected part changes according to the performance operation. However, instead of the above configuration, an alternative configuration in which the area where the coil 61 and the detected part face each other (hereinafter referred to as the "facing area") changes according to the performance operation is also conceivable. In other words, in this disclosure, it is sufficient to have a configuration in which the distance between the coil 61 and the detected part or the facing area changes according to the performance operation, and the frequency response of the filter changes as a result of this change.

[0073] H: Note From the forms exemplified above, the following configuration can be understood, for example.

[0074] A performance control device according to one aspect of the present disclosure (Aspect 1) comprises a movable member that displaces in accordance with a performance operation, a detected part formed of a magnetic material or a conductor and installed on the movable member, and a signal generating unit that generates a detection signal from a reference signal using a coil-based filter, wherein the frequency response of the filter changes according to the distance between the detected part and the coil. According to the above aspect, since the frequency response of the filter to the reference signal changes according to the distance between the detected part and the coil, a detection signal of a level corresponding to that distance is generated. That is, a detection signal corresponding to the position of the movable member is generated. With the above configuration, since the level of the detection signal changes according to the frequency response of the filter, it is possible to significantly change the level of the detection signal in response to the displacement of the movable member. Therefore, there is an advantage in that a detection signal that accurately reflects minute displacements of the movable member can be generated.

[0075] "Movable members" include not only performance controls such as keys or pedals that are directly operated by the user, but also structures such as hammers that are displaced in conjunction with the operation of the performance controls. Furthermore, "distance between the detected part and the coil" typically refers to the shortest distance between the detected part and the coil. Therefore, even in a configuration where the detected part rotates around a fixed central axis (i.e., a configuration where the central axis does not move), the distance between the detected part and the coil can change.

[0076] In a specific example of Embodiment 1 (Embodiment 2), the distance between the detected part and the coil in the direction of the coil's central axis changes according to the displacement of the movable member. According to the above embodiment, compared to a configuration in which the detected part and the coil move relatively in a plane perpendicular to the coil's central axis (i.e., a configuration in which the distance between the detected part and the coil in the direction of the coil's central axis does not change), it is possible to significantly change the level of the detection signal in response to the displacement of the movable member.

[0077] In a specific example of Embodiment 1 or Embodiment 2 (Embodiment 3), the movable member is a performance control operated by the user, and the detected part is an adjustment weight for adjusting the feel of the performance control operated by the user. According to the above embodiments, since the adjustment weight for adjusting the feel of the performance control is also used as the detected part, the configuration of the performance control device is simplified compared to a configuration in which the detected part is installed separately from the adjustment weight.

[0078] In any specific example of Embodiments 1 to 3 (Embodiment 4), the coil includes a first part and a second part, and the direction of the current flowing through the first part and the direction of the current flowing through the second part are opposite. According to the above embodiment, since magnetic fields are generated in opposite directions in the first part and the second part, the diffusion of the magnetic field from the coil to the surroundings is reduced. Therefore, in a configuration in which multiple coils corresponding to different movable members are in close proximity to each other, it is possible to generate a detection signal that accurately reflects the displacement of each of the multiple movable members.

[0079] In a specific example of Embodiment 4 (Embodiment 5), the detected part faces both the first and second parts. According to the above embodiments, since the detected part faces both the first and second parts of the coil, the aforementioned effect of being able to generate a detection signal that accurately reflects minute displacements of the movable member is particularly remarkable. It is not necessary for the detected part to face both the first and second parts over the entire range of displacement of the movable member. That is, it is sufficient for the detected part to face both the first and second parts when the movable member is in a specific position (for example, the position where the detected part is closest to the coil).

[0080] In any specific example of Embodiments 1 to 5 (Embodiment 6), the filter is a low-pass filter that suppresses components in the reference signal that exceed the cutoff frequency, and the cutoff frequency changes depending on the distance between the detected part and the coil.

[0081] In any specific example of Embodiments 1 to 5 (Embodiment 7), the filter is a high-pass filter that suppresses components in the reference signal below the cutoff frequency, and the cutoff frequency changes depending on the distance between the detected unit and the coil.

[0082] In any specific example (8) of Embodiments 1 to 7, the filter is a band-stop filter that suppresses the stopband component in the reference signal, and the stopband changes depending on the distance between the detected unit and the coil.

[0083] A specific example of any of embodiments 1 to 8 (embodiment 9) of the performance control device comprises a sound control unit that generates an acoustic signal representing a sound corresponding to the level of the detection signal. According to the above embodiments, since a detection signal that accurately reflects minute displacements of the movable member is generated, an acoustic signal that reflects minute displacements of the movable member can be generated.

[0084] In any specific example of Embodiments 1 to 9 (Embodiment 10), the detected unit includes a coil. [Explanation of Symbols]

[0085] 100...Keyboard instrument (playing control device), 10...Keyboard, 12...Key, 20...Detection system, 21...Signal processing circuit, 22...Supply circuit, 23...Output circuit, 30...Information processing device, 31...Control device, 32...Memory device, 33...A / D converter, 34...Sound source circuit, 40...Sound emission device, 50...Adjusting weight, 51...Rotating part, 52...Loading part, 60...Signal generation part, 61,61A,61B...Coil, 62,62A,62B...Capacitive element, 63,63A,63B...Resistive element, 91...String striking mechanism, 911...Hammer, 912...Transmission mechanism, 913...Support member, 92...Pedal mechanism, 921...Pedal, 922...Support member, 923...Elastic body.

Claims

1. A movable member that displaces in accordance with the playing motion, A detection unit, formed of a magnetic material or conductor and installed on the movable member, A signal generation unit that generates a detection signal from a reference signal using a high-pass filter with a coil, wherein the frequency response of the high-pass filter changes according to the distance between the unit to be detected and the coil, Support member that supports the movable member and It is equipped with, The aforementioned movable member is a performance control that is operated by the user. The detected part is an adjustment weight for adjusting the feel of the user operating the performance control, The adjustment weight is installed on the opposite side of the support member from the playing control element, and is displaced in conjunction with the movable member. The aforementioned high-pass filter is The input terminal to which the aforementioned reference signal is supplied, An output terminal that outputs the aforementioned detection signal, A first capacitive element connected between the input terminal and the connection point, A second capacitance element connected between the aforementioned connection point and the aforementioned output terminal, The coil includes a first coil connected to the aforementioned connection point and a second coil connected to the aforementioned output terminal, The magnetic field generated in the first coil and the magnetic field generated in the second coil are in opposite directions. Performance operation device.

2. The support member includes a first surface and a second surface, The movable member is supported on the first surface, The signal generation unit is installed on the second surface. The performance control device according to claim 1.

3. Sound control unit that generates an acoustic signal representing sound corresponding to the level of the detected signal. A performance control device according to claim 1 or claim 2, comprising the above.

Images