JP7327646B2 - Displacement sensor and performance control device - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to displacement sensors and performance operating devices.

For example, various techniques have been proposed for detecting displacement of movable members such as keys in keyboard instruments. Patent Document 1 discloses a configuration for detecting displacement of a movable member by using an exciting coil and a position detection coil installed on a fixed member and an excited coil installed on a movable member that moves with respect to the fixed member. is disclosed. Each of the exciting coil, the position detecting coil, and the excited coil is formed in an annular shape parallel to the moving direction of the movable member. In such a configuration, by supplying a periodic signal to generate a magnetic field in the exciting coil, a magnetic field is generated in the excited coil by electromagnetic induction. An induced voltage generated in the position detection coil according to the magnetic field of the energized coil is generated as a detection signal representing the position of the movable member.

JP-A-6-323803

However, in the technique disclosed in Patent Literature 1, there is a possibility that the coil installed on the movable member may be damaged by a tool or the like during maintenance of the movable member. In consideration of such circumstances, one aspect of the present disclosure aims to reduce damage to coils installed on a movable member.

To achieve the above object, a displacement sensor according to one aspect of the present disclosure is a displacement sensor that detects displacement of a movable member according to an operation, is installed on the movable member, and is made of an insulating resin. A relative position between the first coil of the detected part including a first coil protected by a protective member and the second coil that generates a magnetic field when supplied with a current, and the second coil facing it. and a signal generation unit that generates a detection signal according to.

1 is a block diagram showing an example of the configuration of a keyboard instrument to which the displacement sensor according to the first embodiment is applied; FIG. 1 is a block diagram showing an example of the configuration of a keyboard instrument; FIG. FIG. 4 is a diagram showing a circuit of a main part in the displacement sensor; 3 is a block diagram showing an example of a signal processing circuit; FIG. It is a top view which shows the wiring pattern of a to-be-detected part. FIG. 6 is a cross-sectional view taken along line Aa in FIG. 5; It is explanatory drawing, such as a magnetic field which generate|occur|produces with the 1st coil of a to-be-detected part. 3 is a plan view illustrating a specific configuration of a signal generator; FIG. FIG. 9 is a cross-sectional view taken along line BB in FIG. 8; FIG. 4 is an explanatory diagram of a magnetic field generated by a second coil of the signal generator; It is a top view of the to-be-detected part in 2nd Embodiment. FIG. 12 is a cross-sectional view taken along line Cc in FIG. 11; It is a top view of the to-be-detected part in 3rd Embodiment. It is a top view of the to-be-detected part in 4th Embodiment. It is a figure to which the displacement sensor which concerns on a modification is applied. It is a figure to which the displacement sensor which concerns on a modification is applied.

A: First Embodiment FIG. 1 is a block diagram illustrating the configuration of a keyboard instrument 100 to which a displacement sensor according to a first embodiment of the present disclosure is applied.
A keyboard instrument 100 is an electronic musical instrument that includes a keyboard 10 , a detection system 15 , an information processing device 30 and a sound emitting device 40 . A keyboard 10 is composed of a plurality of keys 12 including a plurality of white keys and a plurality of black keys. Each of the plurality of keys 12 is a movable member that is displaced according to the performance operation by the user. A detection system 15 detects the displacement (position) of the key 12 . The information processing device 30 generates an acoustic signal V according to the detection result of the detection system 15 . 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 emitting device 40 emits the sound represented by the acoustic signal V. FIG. For example, a speaker or headphones are used as the sound emitting device 40 .

FIG. 2 is a block diagram illustrating a specific configuration of the keyboard instrument 100, focusing on one key 12 of the keyboard 10. As shown in FIG. Each key 12 of the keyboard 10 is supported by a support member 14 with a fulcrum portion (balance pin) 13 as a fulcrum. The support member 14 is a structure that supports each element of the keyboard instrument 100 . The end portion 121 of each key 12 is displaced in the vertical direction by key depression and key release by the user. The detection system 15 generates a detection signal D whose level corresponds to the position Z of the end 121 in the vertical direction for each of the plurality of keys 12 . The position Z is expressed, for example, by the amount of displacement of the end portion 121 with reference to the position of the end portion 121 in the released state where no load acts on the key 12 .

The detection system 15 comprises a displacement sensor 20 provided for each key 12 and a signal processing circuit 21 common to each key 12 . The displacement sensor 20 is a position sensor that detects the position of each key 12 and includes a detected portion 50 and a signal generating portion 60 . The signal generator 60 is installed on the support member 14 . The detected part 50 is installed on the key 12 . Specifically, the detected portion 50 is installed on the bottom surface (hereinafter referred to as “installation surface”) 122 of the key 12 . Detected portion 50 includes a first coil 51 . The signal generator 60 includes a second coil 61 . The first coil 51 and the second coil 61 face each other with a space therebetween in the vertical direction. The distance between the signal generating portion 60 and the detected portion 50 (the distance between the first coil 51 and the second coil 61) varies depending on the change in the position Z of the end portion 121 of the key 12 due to key depression and key release. Change.

FIG. 3 is a circuit diagram illustrating an electrical configuration of the detected portion 50 and the signal generating portion 60 that constitute the displacement sensor 20. As shown in FIG. The signal generator 60 includes an input terminal T1, an output terminal T2, a second coil 61, a capacitive element 62, a capacitive element 63, and a resistive element 64. A resonance circuit is configured by the second coil 61 , the capacitive element 62 , the capacitive element 63 and the resistive element 64 . The input terminal T1 is connected to one end of the resistance element 64 and the other end of the resistance element 64 is connected to one end of the capacitance element 62 and one end of the second coil 61 . The other end of the second coil 61 is connected to the output terminal T2 and one end of the capacitive element 63 . The other end of the capacitive element 62 and the other end of the capacitive element 63 are grounded to the potential Gnd, which is the zero voltage reference.

On the other hand, the detected portion 50 includes a first coil 51 and a capacitive element 52 . One end of the first coil 51 and one end of the capacitive element 52 are connected to each other, and the other end of the first coil 51 and the other end of the capacitive element 52 are connected to each other. A resonance circuit is configured by the first coil 51 and the capacitive element 52 . The resonance frequency of the signal generating section 60 is set according to the relationship with the resonance frequency of the detected section 50, for example. The resonance frequency of the signal generating section 60 is set to, for example, a frequency substantially equal to the resonance frequency of the detected section 50 or a frequency obtained by multiplying the resonance frequency of the detected section 50 by a predetermined constant.

The signal processing circuit 21 of FIG. 2 generates a detection signal D whose level corresponds to the distance dr between the first coil 51 and the second coil 61 .
FIG. 4 is a block diagram illustrating a specific configuration of the signal processing circuit 21. As shown in FIG. The signal processing circuit 21 comprises a supply circuit 22 and an output circuit 23 . The supply circuit 22 supplies the reference signal R to each of the input terminals T1 of the multiple signal generators 60 . The reference signal R is a voltage signal whose level periodically fluctuates. A periodic signal having an arbitrary waveform such as a sine wave is used as the reference signal R, for example. The supply circuit 22 supplies the reference signal R to each signal generator 60 in a time division manner. Specifically, the supply circuit 22 is a demultiplexer that sequentially selects each of the plurality of signal generators 60 and supplies the reference signal R to the selected signal generators 60 . That is, the reference signal R is supplied to each of the plurality of signal generators 60 in a time division manner. Note that the period of the reference signal R is sufficiently shorter than the length of time during which the supply circuit 22 selects one signal generator 60 . Moreover, the frequency of the reference signal R is substantially equal to the resonance frequencies of the signal generating section 60 and the detected section 50 .

As illustrated in FIG. 3, the reference signal R is supplied to the input terminal T1 of the signal generator 60. As shown in FIG. A magnetic field is generated in the second coil 61 by supplying a current corresponding to the reference signal R to the second coil 61 . An induced current is generated in the first coil 51 by electromagnetic induction due to the magnetic field generated in the second coil 61 . Therefore, a magnetic field is generated in the first coil 51 in a direction that cancels out the change in the magnetic field of the second coil 61 . The magnetic field generated in the first coil 51 changes according to the relative distance dr between the first coil 51 and the second coil 61 . Therefore, a detection signal d having a level δ (peak-to-peak value) corresponding to the relative distance dr between the first coil 51 and the second coil 61 is output from the output terminal T2 of the signal generating section 60 . The detection signal d is a periodic signal whose level fluctuates in the same period as the reference signal R.

The output circuit 23 of FIG. 4 generates the detection signal D by arranging the detection signals d sequentially output from each of the plurality of signal generation units 60 on the time axis. That is, the detection signal D is a voltage signal with a level δ corresponding to the distance dr between the first coil 51 and the second coil 61 in each key 12 . As described above, since the relative distance dr between the first coil 51 and the second coil 61 correlates with the position Z of each key 12, the detection signal D can be expressed as a signal corresponding to the position Z of each of the plurality of keys 12. be. The detection signal D generated by the output circuit 23 is supplied to the information processing device 30 .

The information processing device 30 in FIG. 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 by a computer system including a control device 31 , a storage device 32 , an A/D converter 33 and a tone generator circuit 34 .

The A/D converter 33 converts the detection signal D supplied from the signal processing circuit 21 from analog to digital.
The control device 31 is composed of one or more processors that control each element of the keyboard instrument 100 . For example, the control device 31 includes one or more types of CPU (Central Processing Unit), SPU (Sound Processing Unit), DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), or ASIC (Application Specific Integrated Circuit). Consists of a processor.

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 a known recording medium such as a magnetic recording medium or a semiconductor recording medium. Note that the storage device 32 may be configured by combining multiple types of recording media. Alternatively, a portable recording medium detachable from the keyboard instrument 100 or an external recording medium (for example, an online storage) with which the keyboard instrument 100 can communicate may be used as the storage device 32 .

The control device 31 analyzes the position Z of each key 12 by analyzing the detection signal D converted by the A/D converter 33 . Further, the control device 31 instructs the tone generator circuit 34 to produce musical tones corresponding to the position Z of each key 12 . A tone generator circuit 34 generates an acoustic signal V representing a musical tone instructed by the control device 31 . That is, the sound source circuit 34 detects that the key has reached a predetermined position according to the level δ of the detection signal D, and starts generating the acoustic signal V. FIG. Then, for example, the volume of the acoustic signal V is controlled according to the speed change of the level δ. When the acoustic signal V is supplied from the sound source circuit 34 to the sound emitting device 40, musical tones are emitted from the sound emitting device 40 in accordance with the user's performance operation. Specifically, when the user presses each key 12, a musical tone is emitted, and when the key 12 is released, the musical tone is stopped. Note that the control device 31 may implement the function of the tone generator circuit 34 by executing a program stored in the storage device 32 . The sound source circuit 34 or the control device 31 that implements the function of the sound source circuit 34 functions as a sound control section that generates the sound signal V corresponding to the level δ of the detection signal D. FIG.

First, the signal generator 60 of the displacement sensor 20 will be described. FIG. 8 is a plan view showing a specific configuration of the signal generator 60. As shown in FIG. That is, FIG. 8 is a plan view of the signal generating section 60 as viewed from the detected section 50 side. 9 is a cross-sectional view taken along line BB in FIG.

The signal generator 60 includes a base material 651 and wiring patterns 611 and 612 . Base material 651 is a plate-like member including surface F3 and surface F4. Note that the vertical direction in FIG. 8 is the arrangement direction of the plurality of keys 12 on the keyboard 10 . Surface F4 faces support member 14 . The surface F3 is a surface opposite to the surface F4 and faces the detected portion 50 .

The wiring pattern 611 is formed by patterning a conductive layer such as copper foil provided on the surface F3. The wiring pattern 612 is formed by patterning a conductive layer such as copper foil provided on the surface F4.

The second coil 61 of the signal generation unit 60 includes a fifth portion 621 formed in a spiral shape and a sixth portion formed in a spiral shape in the same direction as the winding direction of the fifth portion 621 in the wiring pattern 611. 622.
One end of the fifth portion 621 is the node N11, and the other end of the fifth portion 621 is the via C11 located at the center of the spiral. One end of the sixth portion 622 is the via C12 located at the center of the spiral, and the other end of the sixth portion 622 is the node N12. Each of via C11 and via C12 is a circular opening penetrating through base material 651 . The via C11 and via C12 are connected to each other through the wiring pattern 612 .

Note that capacitive elements 62 and 63 and a resistive element 64 are mounted on the surface F3. Further, as described above, the reference signal R is supplied from the supply circuit 22 to the input terminal T1. A detection signal d having a level δ corresponding to the distance dr between the first coil 51 and the second coil 61 is output from the output terminal T2.

In the signal generator 60, for example, when current flows through a route of node N12→via C12→via C11→node N11, the current flows counterclockwise in the fifth portion 621 and the current flows clockwise in the sixth portion 622. . 8 and upward in FIG. 10 is generated in the fifth portion 621, and a magnetic field in the depth direction of the page of FIG. 8 and downward in FIG. A magnetic field is generated.
That is, as illustrated in FIG. 10, magnetic fields in opposite directions are generated in the fifth portion 621 and the sixth portion 622 . As described above, the plurality of keys 12 on the keyboard 10 are arranged in the direction perpendicular to the plane of FIG. Therefore, by generating magnetic fields in opposite directions in the fifth portion 621 and the sixth portion 622, the diffusion of the magnetic field across the signal generation sections 60 facing the adjacent keys 12 is reduced. As a result of the reduced diffusion of the magnetic field, the detection signal D that reflects the position Z of each of the plurality of keys 12 with high precision is generated.
Note that FIG. 10 describes the case where the current flows through the path of node N12 → . . . → node N11. .

As described above, the fifth portion 621 and the sixth portion 622 of the second coil 61 in the signal generating section 60 are the spirally formed wiring pattern 611 . Therefore, there is an advantage that the second coil 61 is easy to manufacture and handle, compared to a configuration in which the second coil 61 is formed by winding a conductive wire, for example.

Next, the detected portion 50 of the displacement sensor 20 will be described. The part to be detected 50 in the first embodiment is configured by a substrate including four layers of wiring patterns (wiring layers). FIG. 5 is a plan view showing the wiring patterns of the first to fourth layers in the detected portion 50 as seen through from the signal generating portion 60. FIG.
In addition, in the detected part 50, the wiring pattern closest to the installation surface 122 of the key 12 among the multiple layers of wiring patterns is conveniently the first layer, and along the direction toward the second coil 61 of the signal generation part 60 The second layer, the third layer, and the fourth layer are arranged in order. Also, in FIG. 5, illustration of the capacitive element 52 is omitted for the sake of convenience.

FIG. 6 is a cross-sectional view taken along line Aa in FIG.
The detected portion 50 of the first embodiment includes a first layer wiring pattern 511, a base material 551, a second layer wiring pattern 512, a base material 552, a third layer wiring pattern 513, and a base material. 553 and the wiring pattern 514 of the fourth layer are laminated in this order. That is, in the detected portion 50, the wiring patterns and the substrates are alternately arranged.
The base materials 551, 552 and 553 are rectangular plate members made of insulating resin. Specifically, the base materials 551 and 553 are, for example, prepregs obtained by impregnating glass cloth with a resin such as epoxy and curing the prepreg, and preferably have a thickness of 0.06 mm or more and 0.36 mm or less. The base material 552 is a core material such as glass cloth, and preferably has a thickness of 0.1 mm or more and 1.1 mm or less.

A surface F<b>1 of the detected portion 50 is a surface that is attached to the installation surface 122 of the key 12 . Therefore, the horizontal width W of the detected portion 50 is less than the horizontal width of one key 12 . Further, the surface F2 is the surface opposite to the surface F1. Therefore, the surface F2 faces the signal generator 60 .

A plurality of vias C1 to C8 are provided in the detected portion 50 . The vias C1 to C8 are circular contact holes penetrating through the substrates 551, 552, 553. FIG.

A chip-type capacitive element 52 is mounted on the terminal Na connected to the via C1 and the terminal Nb connected to the via C8 in the wiring pattern 511 . Specifically, one end of the capacitive element 52 is connected to the terminal Na, and the other end is connected to the terminal Nb.
The first coil 51 of the detected portion 50 is composed of a wiring pattern 512 of the second layer and a wiring pattern 513 of the third layer. Specifically, the first coil 51 includes a spirally formed first portion 521 and a fourth portion 524 of the wiring pattern 512 , and a spirally formed second portion 522 and 524 of the wiring pattern 513 . and a third portion 523 .

The center of the spiral in the first portion 521 and the center of the spiral in the second portion 522 are the via C3, and the center of the spiral in the third portion 523 and the center of the spiral in the fourth portion 524 are the via C6. Therefore, the first portion 521 and the second portion 522 overlap each other, and the third portion 523 and the fourth portion 524 overlap each other when viewed in plan from the signal generation section 60 .
Also, the first portion 521 and the fourth portion 524 are adjacent to each other along the longitudinal direction of the key 12 in the second layer. Similarly, the third portion 523 and the fourth portion 524 are adjacent to each other along the longitudinal direction of the key 12 in the third layer.

Terminal Na is connected to one end (node N1) of first portion 521 in the second layer via via C1. The other end of the first portion 521 is connected to one end of the second portion 522 in the third layer through the via C3. The other end (node N2) of the second portion 522 is connected to one end (node N3) of the third portion 523 in the third layer. The other end of the third portion 523 is connected to one end of the fourth portion 524 in the second layer through the via C6. The other end (node N4) of the fourth portion 524 is connected to the first layer terminal Nb through the via C8. Thus, in this embodiment, in the first coil 51, the first portion 521, the second portion 522, the third portion 523, and the fourth portion 524 are connected in series in this order when viewed from the terminal Na.
When the capacitive element 52 is mounted on the terminal Na and the terminal Nb, one end of the capacitive element 52 and one end of the first coil 51 are connected to each other, and the other end of the capacitive element 52 and the other end of the first coil 51 are connected. are interconnected.

A notch 124 is provided on the installation surface 122 of the key 12 as shown in FIG. The notch 124 is a space recessed with respect to the installation surface 122 . The notch 124 is provided by cutting the installation surface 122 with a drill or the like. On the other hand, in the detected portion 50 , the capacitive element 52 protrudes from the surface F<b>1 of the detected portion 50 . With the capacitive element 52 accommodated in the notch 124 , the surface F<b>1 of the detected portion 50 comes into contact with the installation surface 122 of the key 12 .
The capacitive element 52 is exposed before the detected portion 50 is installed on the installation surface 122, but after the detected portion 50 is installed, the capacitative element 52 and the surface F1 are not exposed. Therefore, it is possible to prevent the capacitive element 52 from being caught by another member during maintenance of the keyboard instrument 100 or the like, thereby preventing the capacitive element 52 from being damaged.

When the first coil 51 moves away from the second coil 61 , the first coil 51 receives a magnetic field in a direction that prevents the reduction of the magnetic field generated by the second coil 61 , i.e., the same magnetic field generated by the second coil 61 . A directional magnetic field is generated. Therefore, in this case, a current is induced in the first coil 51 according to the magnetic field in the same direction as the magnetic field generated by the second coil 61 .
For example, when the second coil 61 of the signal generating section 60 generates a magnetic field in the direction shown in FIG. A magnetic field in the same direction as the magnetic field generated by the second coil 61 is generated in the coil 51 as shown in FIG.
Therefore, in FIG. 5, the current flows counterclockwise through the first portion 521 and the second portion 522 of the first coil 51, and the current flows clockwise through the third portion 523 and the fourth portion 524 of the first coil 51 . Therefore, in this case, the current flows through the route of terminal Na→via C1→node N1→via C3→node N2→node N3→via C6→node N4→via C8→terminal Nb.

When the first coil 51 approaches the second coil 61 while the second coil 61 generates a magnetic field in a direction opposite to that in FIG. is generated in the first coil 51 . Therefore, the current similarly flows through the route of terminal Na→...→terminal Nb.
Further, when the first coil 51 approaches the second coil 61 in a state where the second coil 61 generates a magnetic field in the direction shown in FIG. The current flows clockwise in the third portion 523 and the fourth portion 524 in the counterclockwise direction. Similarly, when the first coil 51 separates from the second coil 61 while the second coil 61 generates a magnetic field in the direction opposite to that in FIG. current flows counterclockwise in the third portion 523 and the fourth portion 524 . Therefore, in these cases, the current flows in the opposite direction from terminal Nb to terminal Na.

In the first embodiment, of the first coil 51, the first portion 521 and the fourth portion 524 are the spiral wiring pattern 512, and the second portion 522 and the third portion 523 are the spiral wiring patterns. A wiring pattern 513 is formed. The first coil 51 is composed of a serial connection of a first portion 521 , a second portion 522 , a third portion 523 and a fourth portion 524 .
This configuration has the advantage that the first coil 51 is easy to manufacture and handle, as compared with, for example, a configuration in which the first coil 51 is formed by winding a conductive wire. In addition, it is easier to increase the inductance of the first coil 51 compared to the case where the first coil 51 is configured by only one portion. In other words, when the resonance frequency of the detection target section 50 is matched with the resonance frequency of the signal generation section 60, the capacitance of the capacitive element 52 can be reduced by the amount corresponding to the increase in the inductance of the first coil 51. FIG.

In addition, in the first embodiment, the first portion 521 and the fourth portion 524 of the first coil 51 are covered with the base material 551 and the base material 552 in the detected portion 50 . That is, first portion 521 and fourth portion 524 are formed between substrate 551 and substrate 552 . Also, the second portion 522 and the third portion 523 are covered with the base material 552 and the base material 553 . That is, second portion 522 and third portion 523 are formed between substrate 552 and substrate 553 .
Therefore, the first coil 51 is protected by at least the base material 551 and the base material 553 functioning as protective members. That is, the first coil 51 facing the second coil 61 of the signal generating section 60 is not exposed in the detected section 50 . Therefore, even when the keyboard instrument 100 is disassembled and the keys 12 are removed for maintenance or the like, the first coil 51 is not exposed, so that the first coil 51 is prevented from being damaged by rubbing with a tool or the like.
In the first embodiment, the base material 551 functions as an example of the first insulating layer, the wiring pattern 512 functions as an example of the first wiring pattern, the base material 552 functions as an example of the second insulating layer, The wiring pattern 513 functions as an example of the second wiring pattern, and the base material 553 functions as an example of the third insulating layer. Also, the base material 551 and the base material 553 function as an example of a protective member.

B: Second Embodiment Next, a second embodiment will be described. Note that, in each configuration illustrated below, the reference numerals used in the description of the first embodiment are used for elements having the same functions as those of the first embodiment, and detailed description of each element is appropriately omitted.

The part to be detected 50 in the second embodiment is configured by a substrate including two layers of wiring patterns. FIG. 11 is a plan view showing the wiring patterns of the first layer and the second layer in the detected portion 50 as seen through from the signal generating portion 60. FIG. Note that the illustration of the capacitive element 52 is omitted in FIG. 11 for the sake of convenience. 12 is a sectional view taken along line C--c in FIG. 11. FIG.

The detected portion 50 of the second embodiment is a laminate in which a first layer wiring pattern 511, a base material 551, a second layer wiring pattern 512, and a base material 552 are laminated in this order. That is, in the detected portion 50 of the second embodiment, the wiring pattern 513 of the third layer, the base material 553, and the wiring pattern 514 of the fourth layer are omitted as compared with the first embodiment.

The detected portion 50 is provided with vias C1, C3, C6 and C8. These vias C1, C3, C6 and C8 are contact holes.

In the wiring pattern 511 of the first layer, the capacitive element 52 is mounted in a region A1 including the terminal Na connected to the via C1 and the terminal Nb connected to the via C8.
The first coil 51 of the part to be detected 50 is configured by the wiring pattern 512 of the second layer. Specifically, the first coil 51 is configured by a spiral first portion 521 of the wiring pattern 512 and a second portion 522 spirally formed in the same direction.
In the second embodiment, the center of the spiral in the first portion 521 is the via C3, and the center of the spiral in the second portion 522 is the via C6. Via C3 and via C6 are connected to each other through wiring 515 that is part of wiring pattern 511 .

That is, in the second embodiment, the terminal Na in the area A1 is connected to one end (node N21) of the first portion 521 in the second layer via the via C1. The other end of the first portion 521 is connected to the via C6 via the wiring 515 in the first layer via the via C3. The wiring 515 is connected to the second portion 522 in the second layer through the via C6. The other end (node N22) of the second portion 522 is connected to the terminal Nb in the first layer through the via C8.
Thus, in the first coil 51 of the second embodiment, the first portion 521 and the second portion 522 are connected in series.

In the second embodiment, the total number of parts constituting the first coil 51 is half that of the first embodiment, but the direction of magnetic field generation is the same as in the first embodiment. That is, magnetic fields in opposite directions are generated in the first portion 521 and the second portion 522 . Since the keys 12 of the keyboard 10 are arranged in the direction perpendicular to the plane of FIG. 12, the diffusion of the magnetic field between adjacent keys 12 is reduced. Therefore, it is possible to generate the detection signal D that reflects the position Z of each of the plurality of keys 12 with high accuracy.

In the second embodiment, since the first portion 521 and the second portion 522 that constitute the first coil 51 are covered with the base material 551 and the base material 552, they are not exposed. That is, in the second embodiment, the base material 551 and the base material 552 function as protective members, so that the first coil 51 is protected. Therefore, also in the second embodiment, damage to the first coil 51 due to rubbing with a tool or the like is prevented.
Further, in the second embodiment, the wiring pattern 513 of the third layer, the base material 553 and the wiring pattern 514 of the fourth layer are not present as compared with the first embodiment, so the configuration is simplified accordingly.
In the second embodiment, the base material 551 functions as an example of the first insulating layer, the wiring pattern 512 functions as an example of the first wiring pattern, and the base material 552 functions as an example of the second insulating layer. The base material 551 and the base material 552 function as an example of a protective member.

C: Third Embodiment A third embodiment will be described. The detected part 50 in the third embodiment is configured by a substrate including four layers of wiring patterns, as in the first embodiment. FIG. 13 is a plan view showing the wiring patterns of the first layer and the second layer in the detected portion 50 as seen through from the signal generating portion 60. FIG. 13, illustration of the capacitive element 52 is omitted for the sake of convenience. As in the first embodiment illustrated in FIG. 6, the detected portion 50 of the third embodiment includes a first layer wiring pattern 511, a base material 551, a second layer wiring pattern 512, and a base material 552. , the wiring pattern 513 of the third layer, the base material 553, and the wiring pattern 514 of the fourth layer are laminated in this order.

In the third embodiment, the first coil 51 of the detected portion 50 is configured by the first portion 521 of the wiring pattern 512 of the second layer and the second portion 522 of the wiring pattern 513 of the third layer. . The first portion 521 is spirally formed. The second portion 522 is spirally formed in the opposite direction to the first portion 521 .
In the second embodiment, the center of the spiral in the first portion 521 and the center of the spiral in the second portion 522 are the via C3. That is, in the third embodiment, the first portion 521 and the second portion 522 are connected to each other via the via C3.

Specifically, in the third embodiment, the terminal Na in the area A1 is connected to one end (node N31) of the first portion 521 in the second layer via the via C1. The other end of the first portion 521 is connected to one end of the second portion 522 in the third layer through the via C3. The other end (node N32) of the second portion 522 is connected to the terminal Nb in the region A1 on the first layer through the via C8.
It should be noted that the structure of the detected portion 50 of the third embodiment can be sufficiently analogized from FIG. 6, which is a cross-sectional view of the first embodiment, so illustration is omitted.

In the third embodiment, as in the first embodiment, the second portion 522 constituting the first coil 51 is covered with the base material 552 and the base material 553, so that it is not exposed. That is, in the third embodiment, the base material 552 and the base material 553 function as protective members, so that the first coil 51 is protected. Therefore, also in the third embodiment, damage to the first coil 51 due to rubbing with a tool or the like is prevented.
Also, in the third embodiment, the portion constituting the first coil 51 is halved compared to the first embodiment, but the first portion 521 and the second portion 522 are positioned so as to overlap each other, and the magnetic field occur in the same direction. Therefore, in the third embodiment, the substrate area is approximately half that of the first embodiment. That is, the space required for installation of the detected part 50 is reduced.
In the third embodiment, the base material 551 functions as an example of the first insulating layer, the wiring pattern 512 functions as an example of the first wiring pattern, the base material 552 functions as an example of the second insulating layer, The wiring pattern 513 functions as an example of the second wiring pattern, and the base material 553 functions as an example of the third insulating layer. The base material 552 and the base material 553 function as an example of a protective member.

D: Fourth Embodiment A fourth embodiment will be described. FIG. 14 is a plan view showing the wiring pattern in the detected portion 50 in a see-through state as seen from the signal generating portion 60. As shown in FIG. The first coil 51 of the detected portion 50 in the fourth embodiment is composed of either the first portion 521 or the second portion 522 . That is, the detected part 50 is switched from one of a state in which the first coil 51 is configured by the first portion 521 and a state in which the first coil 51 is configured by the second portion 522 to the other.
A jumper switch 560 is provided on the surface of the first layer. Jumper switch 560 is a switch that connects either via C21 or via C22 to terminal Na in area A1. Specifically, when connecting the terminal Na to the via C21, a socket is inserted as shown in the right column of the figure, and when connecting the terminal Na to the via C22, as shown in the left column of the figure. socket is inserted into the

When jumper switch 560 is positioned as shown in the right column, terminal Na is connected to one end (node N41) of first portion 521 in the second layer via via C21. When jumper switch 560 is positioned as shown in the left column, terminal Na is connected to one end (node N42) of second portion 522 in the third layer via via C22.
The other end of the first portion 521 and the other end of the second portion 522 are connected to the terminal Nb in the region A1 on the first layer via a common via C3.

In the fourth embodiment, the jumper switch 560 is positioned as shown in the left column to cause the second portion 522 to function as the first coil 51 in the initial state when the detected portion 50 is installed, for example. On the other hand, if the second portion 522 has some kind of trouble, the jumper switch 560 is switched to the state shown in the right column to cause the first portion 521 to function as the first coil 51 .
That is, in the fourth embodiment, the first part 521 is used as a spare coil, and the second part 522 is made to function as the first coil 51. If a problem occurs in the second part 522, switching the jumper switch 560 , the first portion 521 can function as the first coil 51 .

As can be understood from the above description, the displacement sensor 20 of the fourth embodiment includes the detected portion 50 installed on the key 12, which is an example of a movable member, and the second coil 61 that generates a magnetic field by supplying current. and a signal generation unit 60 including. Detected portion 50 includes a first portion 521 protected by a protective member (base material 551 or base material 552) made of insulating resin, and a second portion 522, which is an example of a third coil. Jumper switch 560 functions as a switching unit that switches between a first state in which first portion 521 forms a resonant circuit and a second state in which second portion 522 forms a resonant circuit. The signal generating section 60 generates a detection signal corresponding to the relative position between the resonance circuit of the detected section 50 and the second coil 61 . The second portion 522 may or may not be protected by a protective member.

In the fourth embodiment, there may be no member covering the second portion 522, and even if the second portion 522 is damaged, the first portion 521 can be made to function as the first coil 51 by switching the jumper switch 560. be able to. That is, in the fourth embodiment, when the jumper switch 560 causes the first portion 521 to function as the first coil 51 , the base material 552 functions as a protective member, so the first coil 51 is protected.
In the fourth embodiment, the base material 551 functions as an example of the first insulating layer, the wiring pattern 512 functions as an example of the first wiring pattern, the base material 552 functions as an example of the second insulating layer, The wiring pattern 513 functions as an example of the second wiring pattern, and the base material 553 functions as an example of the third insulating layer.

E: Modifications Examples of specific modifications added to the above-exemplified embodiments are given below. Two or more aspects arbitrarily selected from the following examples may be combined as appropriate within a mutually consistent range.

(1) In each of the above embodiments, the configuration for detecting the displacement of the keys 12 of the keyboard instrument 100 is illustrated, but the movable member whose displacement is detected by the displacement sensor 20 is not limited to the keys 12 . Specific aspects of the movable member are exemplified below.

[Aspect 1]
FIG. 15 is a schematic diagram of a configuration in which the displacement sensor 20 is applied to the string-striking mechanism 91 of the keyboard instrument 100. As shown in FIG. The string-striking mechanism 91 is an action mechanism that strikes a string (not shown) in conjunction with displacement of each key 12 of the keyboard 10, like an acoustic piano. Specifically, the string-striking mechanism 91 includes a hammer 911 capable of striking a string by rotation, and a transmission mechanism 912 (for example, a whipen, a jack, a repetition lever, etc.) that rotates the hammer 911 in conjunction with the displacement of the key 12 . , for each key 12 .
A detected part 50 is installed on a hammer 911 (for example, a hammer shank). Also, the signal generator 60 is installed on the support member 913 . In such a configuration, the displacement sensor 20 detects displacement of the hammer 911 . Specifically, the support member 913 is a structure that supports the string-striking mechanism 91, for example. Note that the detected portion 50 may be installed on a movable member other than the hammer 911 in the string-striking mechanism 91 .

[Aspect 2]
FIG. 16 is a schematic diagram of a configuration in which the displacement sensor 20 is applied to the pedal mechanism 92 of the keyboard instrument 100. As shown in FIG. The pedal mechanism 92 includes a pedal 921 that is 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 upward in the vertical direction.
A detected part 50 is installed on the bottom surface of the pedal 921 . Further, the signal generation section 60 is installed on the support member 922 so as to face the detected section 50 . In such a configuration, the displacement sensor 20 detects displacement of the pedal 921 .
Note that the musical instrument using the pedal mechanism 92 is not limited to the keyboard musical instrument 100 . A similarly configured pedal mechanism 92 is utilized for any musical instrument such as, for example, a percussion instrument.

As can be understood from the above examples, the objects to be detected by the displacement sensor are comprehensively represented as movable members that are displaced according to the performance action. The movable members include performance operators such as the keys 12 or pedals 921 that are directly operated by the user, and structures such as the hammers 911 that are displaced in conjunction with operations on the performance operators. However, the movable member in the present disclosure is not limited to a member that displaces according to the performance action. In other words, the movable member is generically expressed as a member that can be displaced regardless of the trigger that causes the displacement.

(2) In the above-described embodiment, the configuration in which the capacitive element 52 on the surface F1 is connected to the wiring pattern 511 formed on the surface F1 of the detected portion 50 is illustrated, but the wiring pattern (512 or 513) may be connected to the capacitive element 52 on the surface F1 by, for example, a blind via. In a configuration in which the capacitive element 52 is connected to the wiring pattern between the insulating layers, the wiring pattern 511 may be omitted from the detected portion 50 . That is, a configuration in which the wiring pattern 511 does not exist on the surface F1 of the detected portion 50 is also assumed. In the above configuration, if the above-described configuration in which the capacitive element 52 is accommodated in the cutout portion 124 of the installation surface 122 is adopted, the above-described effect of suppressing damage to the capacitative element 52 is particularly remarkable.

(3) In the above-described embodiments, the substrates (552, 553) were exemplified as protective members, but the form of the protective member is not limited to the above examples. For example, an insulating layer formed on the surface of a flat substrate may be used as the "protective member". The insulating layer is, for example, a film intended for waterproofing, and is formed of an insulating material such as silicon, epoxy, or urethane. Various processing techniques, such as coating or potting, are used to form the insulating layer. As understood from the above description, the concept of "protective member" includes not only an independent base material but also a film body covering the surface of the base material.

(4) In each of the above-described embodiments, the keyboard instrument 100 includes the tone generator circuit 34. However, in a configuration in which the keyboard instrument 100 includes a sound generating mechanism such as the string striking mechanism 91, the tone generator circuit 34 may be used. May be omitted. The detection system 15 is used to record performance content of the keyboard instrument 100 . The sound generator and sound source circuit 34 are generically represented as sound generators that produce sounds in response to detection by the detection system 15 .

As can be understood from the above description, the present disclosure is also specified as a device (performance operation device) that controls musical tones by outputting operation signals corresponding to performance operations to the tone generator circuit 34 or the sound generating mechanism. In addition to a musical instrument (keyboard instrument 100) having a tone generator circuit 34 or a sounding mechanism as exemplified in each of the above embodiments, a device not equipped with a tone generator circuit 34 or a sounding mechanism (for example, a MIDI controller or the pedal mechanism 92 described above) Included in the concept of an instrument playing apparatus. That is, the performance operation device in the present disclosure is comprehensively expressed as a device operated by a performer (operator) for performance.

(5) In the above-described embodiments, the protective member of the present disclosure has a configuration in which the entire surface is covered with a resin layer, but the entire surface may not necessarily be covered. For example, the protective member may be a mesh-like member covering the pattern. Also, the prismatic members may be arranged side by side in the longitudinal direction or the lateral direction of the substrate with no gap between the members or with a predetermined gap. Alternatively, only the coil pattern portion may be covered with the protective member.

F: Supplementary Note The following aspects, for example, can be understood from the above-described embodiments and the like.

A displacement sensor according to an aspect (first aspect) of the present disclosure is a displacement sensor that detects displacement of a movable member according to an operation, and is installed on the movable member and protected by a protective member made of insulating resin. and a second coil that generates a magnetic field when supplied with a current, and detection according to the relative position of the first coil of the detected part and the second coil facing it and a signal generator that generates a signal.
According to this aspect, since the first coil is protected by the protective member, it is possible to prevent the first coil from being damaged due to rubbing or the like.

In the example of the first aspect (second aspect), the distance between the first coil and the second coil in the direction of the central axis of the second coil changes according to the displacement of the movable member.
According to this aspect, the detected portion and the second coil move relatively in a plane perpendicular to the central axis of the second coil (that is, the detected portion and the second coil move in the direction of the central axis of the second coil). Compared to the configuration in which the distance to the two coils does not change), it is possible to greatly change the level of the detection signal with respect to the displacement of the movable member.

In the example of the first or second aspect (third aspect), the detected part includes a capacitive element connected to the first coil. According to this aspect, there is an advantage that the resonance frequency by the first coil and the capacitive element can be adjusted according to the capacitance of the capacitive element.

In the example of the third aspect (fourth aspect), the movable member has an installation surface on which the detected part is installed, the installation surface is provided with a notch, and the capacitive element is provided in the notch. The part to be detected is installed on the movable member in the accommodated state.
According to this aspect, since the capacitive element mounted on the substrate is not exposed, it is possible to prevent the capacitive element from being damaged by being caught by other members during maintenance or the like.

In any example of the first to fourth aspects (fifth aspect), the part to be detected includes at least a first insulating layer, a first wiring pattern and a second insulating layer, and the first wiring pattern includes the Located between the first insulating layer and the second insulating layer, the first coil is a spiral portion included in the first wiring pattern.
According to this aspect, there is an advantage that the first coil is easy to manufacture and handle, compared with a configuration in which the first coil is formed by winding a conductive wire, for example.

In any example of the first to fourth aspects (sixth aspect), the part to be detected includes at least a first insulating layer, a first wiring pattern, a second insulating layer, a second wiring pattern and a third insulating layer. wherein the first wiring pattern is located between the first insulating layer and the second insulating layer, the second wiring pattern is located between the second insulating layer and the third insulating layer, The first coil includes a first portion, a second portion, a third portion, and a fourth portion, and the first portion and the fourth portion are spiral-shaped portions included in the first wiring pattern. , the second portion and the third portion are spiral-shaped portions included in the second wiring pattern, the first portion and the second portion overlap each other in a plan view, and the third portion and the The fourth portion overlaps with each other in plan view, the magnetic field generated by the first portion and the magnetic field generated by the second portion are in the first direction, and the magnetic field generated by the third portion and the magnetic field generated by the fourth portion is in a second direction opposite to the first direction.
According to this aspect, a magnetic field in the first direction is generated in the first portion and the second portion, and a magnetic field in the direction opposite to the first direction is generated in the third portion and the fourth portion, so that the first coil from the spread of the magnetic field to the surroundings is reduced. Therefore, in a configuration in which a plurality of first coils corresponding to different movable members are close to each other, it is possible to generate a detection signal reflecting the displacement of each of the plurality of movable members with high accuracy.

Note that "planar view" means observing along a direction perpendicular to the surface of the wiring pattern, or observing from a direction perpendicular to the surface of the insulating layer. Observation along the axial direction of the first coil may be expressed as "plan view".

In any example of the first to fourth aspects (seventh aspect), the detected portion includes at least a first insulating layer, a first wiring pattern, and a second insulating layer, and the first wiring pattern includes the Positioned between a first insulating layer and the second insulating layer, the first coil includes a first portion and a second portion, the first portion and the second portion being connected to the first wiring pattern. A spiral-shaped portion is included, wherein the magnetic field generated by the first portion and the magnetic field generated by the second portion are in opposite directions to each other.
According to this aspect, the first portion and the second portion overlap in plan view, and the generated magnetic field is in the same direction. be able to.

In any example of the first to fourth aspects (eighth aspect), the part to be detected includes at least a first insulating layer, a first wiring pattern, a second insulating layer, a second wiring pattern and a third insulating layer. wherein the first wiring pattern is located between the first insulating layer and the second insulating layer, the second wiring pattern is located between the second insulating layer and the third insulating layer, The first coil includes a first portion and a second portion, the first portion being a spiral-shaped portion included in the first wiring pattern, and the second portion being in the second wiring pattern. spiral-shaped portion included, the first portion and the second portion overlap each other in plan view, and the magnetic field generated by the first portion and the magnetic field generated by the second portion overlap each other in the same direction.
According to this aspect, since the first portion and the second portion overlap in a plan view, the space required for installing the detected portion can be reduced.

In any one of the first to fourth aspects (the ninth aspect), the part to be detected includes a third coil, a first state in which the first coil forms a resonance circuit, and a state in which the third coil resonates. a switching unit for switching between a second state and a second state forming a circuit; According to this aspect, even if another coil is damaged, the other coil can be used by replacing it with the first coil protected by the protective member.

A performance operating device according to one aspect (tenth aspect) of the present disclosure includes the displacement sensor according to any one of the first to ninth aspects, and generates an acoustic signal representing a sound according to the level of the detection signal. and a sound controller.

DESCRIPTION OF SYMBOLS 100... Keyboard instrument (performance operation apparatus), 10... Keyboard, 12... Key, 15... Detection system, 20... Displacement sensor, 21... Signal processing circuit, 22... Supply circuit, 23... Output circuit, 30... Information processing apparatus, 50... Detected portion, 51... First coil, 52... Capacitive element, 521... First part, 522... Second part, 523... Third part, 524... Fourth part, 551, 552, 553... Base material.

Claims (10)

A displacement sensor that detects displacement of a movable member according to an operation,
A detection target portion installed on an installation surface of the movable member, the protection member being formed of an insulating resin , a first coil protected by the protection member , and a capacitive element connected to the first coil. and a detected part including
a signal generator that includes a second coil that generates a magnetic field when supplied with a current and that generates a detection signal according to the relative position of the first coil of the detected portion and the second coil facing the first coil;
and
The part to be detected is installed on the movable member in a state in which the capacitive element is accommodated in the notch formed in the installation surface.
displacement sensor. The part to be detected is installed on the movable member in a state in which the surface of the protective member is in contact with the installation surface and the capacitive element protruding from the surface of the protective member is accommodated in the notch. Item 1. The displacement sensor according to item 1. 3. The displacement sensor according to claim 1, wherein the distance between the first coil and the second coil in the direction of the central axis of the second coil changes according to the displacement of the movable member. The part to be detected is
including at least a first insulating layer, a first wiring pattern and a second insulating layer;
the first wiring pattern is located between the first insulating layer and the second insulating layer;
The displacement sensor according to any one of claims 1 to 3, wherein the first coil is a spiral portion included in the first wiring pattern. The part to be detected is
including at least a first insulating layer, a first wiring pattern, a second insulating layer, a second wiring pattern and a third insulating layer;
the first wiring pattern is located between the first insulating layer and the second insulating layer;
the second wiring pattern is located between the second insulating layer and the third insulating layer;
the first coil includes a first portion, a second portion, a third portion, and a fourth portion;
The first portion and the fourth portion are spiral-shaped portions included in the first wiring pattern,
the second portion and the third portion are spiral-shaped portions included in the second wiring pattern;
the first portion and the second portion overlap each other in plan view;
the third portion and the fourth portion overlap each other in plan view,
the magnetic field generated by the first portion and the magnetic field generated by the second portion are in a first direction;
The displacement according to any one of claims 1 to 3, wherein the magnetic field generated by the third portion and the magnetic field generated by the fourth portion are in a second direction opposite to the first direction. sensor. The part to be detected is
including at least a first insulating layer, a first wiring pattern and a second insulating layer;
the first wiring pattern is located between the first insulating layer and the second insulating layer;
the first coil includes a first portion and a second portion;
The first portion and the second portion are spiral-shaped portions included in the first wiring pattern,
4. The displacement sensor according to any one of claims 1 to 3, wherein the magnetic field generated by the first portion and the magnetic field generated by the second portion are opposite to each other. The part to be detected is
including at least a first insulating layer, a first wiring pattern, a second insulating layer, a second wiring pattern and a third insulating layer;
the first wiring pattern is located between the first insulating layer and the second insulating layer;
the second wiring pattern is located between the second insulating layer and the third insulating layer;
the first coil includes a first portion and a second portion;
The first portion is a spiral-shaped portion included in the first wiring pattern,
The second portion is a spiral-shaped portion included in the second wiring pattern,
the first portion and the second portion overlap each other in plan view;
The displacement sensor according to any one of claims 1 to 3 , wherein the magnetic field generated by the first portion and the magnetic field generated by the second portion are in the same direction. A displacement sensor that detects displacement of a movable member according to an operation,
A first state in which a first coil, a third coil, and the first coil, which is a detected portion provided on the movable member and protected by a protective member made of an insulating resin, constitutes a resonance circuit. and a detecting portion including a switching portion for switching between and a second state in which the third coil forms a resonant circuit ;
a signal generator that includes a second coil that generates a magnetic field when supplied with a current and that generates a detection signal according to the relative position of the first coil of the detected portion and the second coil facing the first coil;
a displacement sensor. The first coil and the third coil overlap each other in plan view.
9. The displacement sensor of claim 8. a displacement sensor according to any one of claims 1 to 9 ;
a sound control unit that generates an acoustic signal representing a sound corresponding to the level of the detection signal;
A performance operation device comprising

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