Keyboard device key operation detection device, keyboard device key operation detection method and keyboard device

Abstract

A detection device (101) for key operation of a keyboard device is provided, comprising: a key-side conductive portion (20) arranged on each key (13) of a plurality of keys (13); a circuit substrate (15) arranged to be opposite to the plurality of keys (13) in the pressing direction of the plurality of keys (13); a plurality of sensor portions (30), each having a coil, arranged on the circuit substrate (15) corresponding to each key (13) and outputting a signal corresponding to the distance from the key-side conductive portion (20) arranged on the corresponding key (13); and a detection portion (50) which detects the position of the corresponding key (13) in the pressing direction and the displacement in the front-rear direction based on the signal output from the sensor portion (30).

Description

Technical Field

[0001] The invention relates to a key operation detection device of a keyboard device, a key operation detection method and a keyboard device with the detection device. Background Art

[0002] In the past, a keyboard device is known in which a resonant circuit having a coil is provided between a key and a substrate as a non-contact sensor, and the position and speed of the key are detected based on the signal output from the resonant circuit of the substrate (Patent Document 1). Patent Document 1 can detect the position and speed of the key in the pressing direction using a signal output unit (resonant circuit) having a coil. However, the key cannot be displaced in the front-rear direction.

[0003] On the other hand, keyboard devices having keys that can be displaced in the front-rear direction are disclosed in Patent Documents 2 and 3. Patent Documents 2 and 3 can detect the displacement of the keys in the front-rear direction.

[0004] Patent Document 1: International Patent Publication WO2019 / 122867A1

[0005] Patent document 2: US7723597

[0006] Patent Document 3: Japanese Utility Model Publication No. 49-004621 Summary of the invention

[0007] However, in Patent Documents 2 and 3, the displacement in the pressing direction and the displacement in the front-rear direction of the key are detected at different positions. Therefore, it is necessary to provide a signal output unit for detecting the displacement in the pressing direction and the displacement in the front-rear direction, respectively.

[0008] An object of the present invention is to provide a key operation detection device for a keyboard device that can detect not only the position of a key in a pressing direction but also the displacement of a key in a front-rear direction based on the output of a signal output unit.

[0009] According to one embodiment of the present invention, there is provided a device for detecting key operations of a keyboard device, comprising: a conductive portion, which is arranged on each of a plurality of keys; a substrate, which is arranged opposite to the plurality of keys in the pressing direction of the plurality of keys; a plurality of signal output portions, each having a coil, which is arranged on the substrate corresponding to each of the plurality of keys and outputs a signal corresponding to the following distance, which is the distance between the signal output portion and the conductive portion arranged on the corresponding key; and a detection portion, which detects the position of the corresponding key in the pressing direction and the displacement of the corresponding key in the front-rear direction based on the signals output from the plurality of signal output portions.

[0010] Effects of the Invention

[0011] According to one aspect of the present invention, not only the position of a key in the pressing direction but also the displacement of the key in the front-rear direction can be detected based on the output of the same signal output unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a schematic side view of a keyboard device.

[0013] Figure 2 It is a schematic diagram of the main parts of the operation detection device.

[0014] Figure 3 It is a schematic plan view showing a configuration example of the key-side conductive portion and the sensor portion.

[0015] Figure 4 This is an enlarged view of the first conductive portion observed in a plan view.

[0016] Figure 5 This is an enlarged view of the first signal output portion obtained by plan view.

[0017] Figure 6 This is a circuit diagram of the first conductive portion.

[0018] Figure 7 This is a circuit diagram of the first signal output section.

[0019] Figure 8 This is a schematic front view of one key and the sensor portion corresponding thereto.

[0020] Fig. 9 It is a schematic plan view showing a configuration example of the key-side conductive portion and the sensor portion.

[0021] Fig.10 It is a schematic plan view showing a first structural example of the key-side conductive portion and the sensor portion according to the second embodiment.

[0022] Fig.11 It is a schematic plan view showing a second structural example of the key-side conductive portion and the sensor portion.

[0023] Fig.12 This is a schematic front view of one key and the sensor portion corresponding thereto.

[0024] Fig.13 This is a schematic front view of one key and the sensor portion corresponding thereto.

[0025] Fig.14 It is a schematic plan view showing a configuration example of a first modification of the key-side conductive portion and the sensor portion.

[0026] Fig.15 It is a schematic plan view showing a configuration example of a second modification of the key-side conductive portion and the sensor portion. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0028] (First embodiment)

[0029] Figure 1 This is a schematic side view of a keyboard device to which the key operation detection device according to the first embodiment of the present invention is applied. Figure 1 FIG. 1 is a diagram focusing on one key 13 among the plurality of keys 13 of the keyboard device 100. Figure 1 In the embodiment, the front end side of the length direction of the key 13 is the front, and the key surface (surface) side is the top. The left-right direction refers to the direction observed from the front side of the key 13 where the performer is located. Therefore, the key arrangement direction is the same as the left-right direction. The length direction of the key 13 is also the front-back direction. The keyboard device 100 is suitable for application to electronic keyboard instruments, and is also suitable for devices that output sound signals without generating sound.

[0030] A leaf spring 19 is provided on the frame 11. A fulcrum 12 is fixed to the upper end of the leaf spring 19. The leaf spring 19 can bend in the front-to-back direction (Y direction). The leaf spring 19 stands straight without being bent in a non-operating state in which the key 13 is not operated. With the bending of the leaf spring 19, the fulcrum 12 is displaced in the front-to-back direction. As the fulcrum 12 is displaced in the front-to-back direction, the entire key 13 is also displaced in the front-to-back direction. The front end portion of the key 13 can be rotated in the up-down direction (Z direction) with the fulcrum 12 as the center. Thus, through operation, the key 13 can be displaced in the front-to-back direction and rotated with the fulcrum 12 as the center in parallel.

[0031] The key 13 has a protrusion 16 and a protrusion 17. A key-side conductive portion 20 described later is provided at the lower end of the protrusion 16. A circuit substrate 15 is provided on the frame 11. The circuit substrate 15 is provided opposite to each key 13 in the direction in which the keys 13 are pressed. A sensor portion 30 described later is arranged on the circuit substrate 15 corresponding to the key-side conductive portion 20.

[0032] A coil spring 14 is installed in a compressed state between the key 13 and the frame 11. The coil spring 14 always pushes the key 13 upward. A lower limit stopper 18 is provided on the frame 11 opposite to the protrusion 17. The key 13 in the non-operated state hits the upper limit stopper (not shown) and is thereby restricted. Figure 1The initial position (non-key position) shown. If the performer presses the key 13, the coil spring 14 is compressed, and the protrusion 17 contacts the lower limit stopper 18. The lower limit position of the key stroke of the protrusion 17 is limited by the lower limit stopper 18. The lower limit stopper 18 can be elastically deformed within a specified range, and is elastically deformed by being pressed by the protrusion 17. The position where the lower limit stopper 18 is elastically deformed within a specified range becomes the lower limit position of the key stroke of the protrusion 17. The lower limit stopper 18 and the stopper for specifying the lower limit position may also be provided separately. If the performer releases the key 13 from the key pressing end state where the protrusion 17 has pressed the lower limit stopper 18, the key 13 returns to the initial position due to the force of the coil spring 14.

[0033] During the key stroke of the key 13, the key side conductive part 20 approaches the sensor part 30, and during the key release stroke of the key 13, the key side conductive part 20 moves away from the sensor part 30. Here, even if the protrusion 17 reaches the lowest limit position, the key side conductive part 20 does not contact the sensor part 30. Therefore, the key side conductive part 20 and the sensor part 30 are always in a non-contact relationship. The details will be described later. The key side conductive part 20 is composed of a pair of conductive parts 21 and 22 ( Figure 3 The sensor unit 30 includes, for example, two (a pair of) signal output units 31 and 32 ( Figure 3 ), which is the distance between the signal output parts 31, 32 and the key-side conductive part 20 of the corresponding key 13.

[0034] There are a plurality of white keys and a plurality of black keys in the plurality of keys 13. The plurality of keys 13 are arranged in the left-right direction (key arrangement direction) when viewed from the performer. The structures of each key 13 and the corresponding key-side conductive portion 20 and sensor portion 30 are common. The front end portion of the key 13 swings in the pressing direction, i.e., the pitch direction, through pressing and releasing operations. In addition, if the performer applies force to the key 13 forward and backward during the process of pressing the key 13 or in the pressed state, the leaf spring 19 is deformed and the key 13 is displaced in the front-back direction together with the fulcrum 12.

[0035] In the past, by further key operation at the end of key pressing, the after touch distance is detected and used for sound control, thereby widening the expression of sound. Representatively, as the after touch distance, the increase or decrease of the force in the pressing direction is detected at the end of key pressing. However, in addition to this, if the after touch distance can be generated by the performer intentionally causing the key to be displaced in the front-to-back direction at the end of key pressing, the expressiveness is improved. As described in detail later, in this embodiment, through the combination of the key-side conductive part 20 and the sensor part 30, it is possible to detect not only the stroke position of the key 13 but also the displacement in the front-to-back direction in a non-contact manner. Moreover, they can detect not only at the end of key pressing, but also in the middle of key pressing and key releasing.

[0036] Figure 2 It is a schematic diagram of the main parts of the operation detection device 101. In addition to the key-side conductive part 20 and the sensor part 30, the operation detection device 101 also includes an adding part 51, a subtracting part 52 and a control part 50. The detection part of the present invention mainly includes an adding part 51, a subtracting part 52 and a control part 50. Although the control part 50 is not shown in the figure, it includes a CPU, a RAM, a ROM, a timer, etc. The sound generating part 53 includes a sound source circuit and an effect circuit. The control part 50 controls the sound generation achieved by the sound generating part 53 based on the detection results of the operation of each key 13 detected by the operation detection device 101. For example, the control part 50 controls the generation and muting of the sound based on the detection results in the pitch direction, and controls the effect of the generated sound based on the detection results related to the displacement in the front-back direction. The details of the effect assignment will be described later.

[0037] Figure 3 2 is a schematic plan view showing a configuration example of the key-side conductive portion 20 and the sensor portion 30. Figure 3 In FIG. 1 , the key-side conductive portion 20 is shown as a projection diagram obtained by plan view (plane view). Figure 3 To the left is the rear of a key 13 of the fulcrum 12. In addition, Figure 3 In the figure, capacitors and resistors are omitted. The key-side conductive portion 20 includes a pair of conductive portions (a first conductive portion 21 and a second conductive portion 22). The first conductive portion 21 and the second conductive portion 22 are arranged in a front-to-back direction. The first conductive portion 21 is a circuit having a coil connected to two spiral portions (winding portions 23 and 24). The second conductive portion 22 is a circuit having a coil connected to two spiral portions (winding portions 25 and 26).

[0038] The sensor unit 30 is provided corresponding to each key 13, and includes a pair of signal output units (a first signal output unit 31 and a second signal output unit 32). The first signal output unit 31 and the second signal output unit 32 are arranged in a front-to-back direction. The first signal output unit 31 is a circuit having a coil with two spiral parts connected. The second signal output unit 32 is also a circuit having a coil with two spiral parts (winding parts 35 and 36) connected. The structure of the first conductive part 21 and the second conductive part 22 is common. The structure of the first signal output unit 31 and the second signal output unit 32 is common. Use Figures 4 to 7 , the detailed structures of the first conductive portion 21 and the first signal output portion 31 are representatively described.

[0039] Figure 4 This is an enlarged view of the first conductive portion 21 obtained by top view. The first conductive portion 21 has a coil C21 that is in the shape of an "8" as a whole. The coil C21 is arranged in a plane at the lower end of the protrusion 16. The coil C21 is continuous from the via hole 27 to the via hole 28 via the capacitor 29. In addition, the via hole 27 and the via hole 28 are directly connected on the back side of the substrate. The winding portion 23 and the winding portion 24 are adjacent to each other. The center of gravity position of each of the winding portions 23 and 24 is set as the center of gravity G1 and G2. In addition, the center of gravity G1 and G2 are defined as the center of gravity position of the figure of the winding portions 23 and 24 having an approximately circular contour shape. Alternatively, the center of gravity G1 and G2 can also be defined as the center of gravity position of each of the winding portions 23 and 24 with a focus on mass. The straight line L1 passing through the center of gravity G1 and G2 is approximately parallel to the key arrangement direction. A straight line L2 ( Figure 3 ) is also approximately parallel to the key arrangement direction. Therefore, the first conductive portion 21 and the second conductive portion 22 are arranged so that the straight lines L1 and L2 are approximately parallel.

[0040] Figure 5 This is an enlarged view of the first signal output unit 31 obtained by top view. The first signal output unit 31 has a coil C31 that is in the shape of an "8" as a whole. The coil C31 is arranged in a planar shape on the circuit substrate 15. The coil C31 is continuous from the via hole 37 to the via hole 38 via the capacitors 39 and 40. In addition, the via hole 37 and the via hole 38 are directly connected on the back side of the substrate. The resistor 41 is connected to the capacitor 39, and the resistor 42 is connected to the capacitor 40. Resistors 41 and 42 are not necessarily provided. The winding portion 33 and the winding portion 34 are adjacent to each other. The center of gravity positions of the winding portions 33 and 34 are respectively set as the center of gravity G3 and G4. In addition, the definition of the center of gravity G3 and G4 is the same as that of the center of gravity G1 and G2. The straight line L3 passing through the center of gravity G3 and G4 is approximately parallel to the key arrangement direction. The straight line L4 ( Figure 3) is also approximately parallel to the key arrangement direction. Therefore, the first signal output unit 31 and the second signal output unit 32 are configured so that the straight lines L3 and L4 are approximately parallel. Figure 3 As shown, the interval between the straight lines L3 and L4 is wider than the interval between the straight lines L1 and L2.

[0041] like Figure 4 As shown, the vortex directions of the winding portions 23 and 24 with the center as the base point are the same. That is, the vortex direction of the winding portion 23 when the passage hole 28 close to the center of gravity G1 is regarded as the starting point is the right-hand (clockwise) direction. The vortex direction of the winding portion 24 when the passage hole 27 close to the center of gravity G2 is regarded as the starting point is also the right-hand direction. According to the relationship described above, when a current in a certain direction flows through the coil C21, the direction of the magnetic flux is opposite in the winding portion 23 and the winding portion 24. Similarly, Figure 5 As shown, the swirl directions of the windings 33 and 34 are the same with respect to the center. When a current in a certain direction flows through the coil C31, the directions of the magnetic flux are opposite in the windings 33 and 34.

[0042] Figure 6 2 is a circuit diagram of the first conductive portion 21 . Figure 7 : is a circuit diagram of the first signal output unit 31. The first conductive unit 21 is configured as a resonant circuit on the passive side. The first conductive unit 21 is a closed circuit. The first signal output unit 31 is configured as a resonant circuit on the active side. The above-mentioned resonant circuit is basically the same as the structure disclosed in Patent Document 1 (WO2019 / 122867A1).

[0043] In the first signal output unit 31, the input terminal 44 is connected to a driving circuit (not shown). The detection signal is taken out from the output terminal 43. Figure 2 As shown, the detection signal from the second signal output unit 32 is input to the + terminal of the adder 51 and the + terminal of the subtractor 52. The detection signal from the first signal output unit 31 is input to the other + terminal of the adder 51 and the - terminal of the subtractor 52. In addition, in order to correct the phase deviation between the detection signal from the first signal output unit 31 and the detection signal from the second signal output unit 32, the respective outputs may be input to the adder 51 and the subtractor 52 via a smoothing circuit (not shown). The adder 51 outputs the sum of the detection signals from the first signal output unit 31 and the second signal output unit 32 to the control unit 50. The subtractor 52 outputs the difference between the detection signal from the first signal output unit 31 and the detection signal from the second signal output unit 32 to the control unit 50. The above detection signal is a continuous quantity.

[0044] The output of the signal output parts 31 and 32 is, for example, a voltage value. When the signal output parts 31 and 32 are driven at a predetermined resonant frequency, if the first conductive part 21 approaches the first signal output part 31, then in the first conductive part 21, a current flows in a direction that cancels out the magnetic flux generated in the first signal output part 31. As a result, the magnetic flux of the first signal output part 31 changes, and the voltage changes. Therefore, the detection signal can be taken out as a voltage value. As the first conductive part 21 approaches the first signal output part 31, the output of the first signal output part 31 decreases. Similarly, if the second conductive part 22 approaches the second signal output part 32, the output of the second signal output part 32 decreases accordingly. That is, the output (voltage) of the signal output parts 31 and 32 changes in accordance with the distance from the corresponding conductive parts 21 and 22, and the shorter the distance, the smaller the output (voltage). In addition, as the output of the signal output parts 31 and 32, the change of the resonant signal and the current value can also be used.

[0045] In particular, as described above, both the coil C21 and the coil C31 are in the shape of an "8". Therefore, the relationship between the first signal output part 31 and the first conductive part 21 is as follows. First, in a state where an upward magnetic flux is generated from the winding part 33 of the first signal output part 31 and a downward magnetic flux is generated from the winding part 34, the first conductive part 21 is set to approach the first signal output part 31. Then, a current flows in the winding part 23 of the first conductive part 21 in a direction that cancels out the upward magnetic flux from the winding part 33. As a result, an upward magnetic flux is generated in the winding part 24 of the first conductive part 21, and therefore, the downward magnetic flux of the winding part 34 of the first signal output part 31 is weakened. Therefore, compared with a structure in which the winding directions of the winding part 33 and the winding part 34 are opposite, the variation range of the output of the first signal output part 31 is large. As a result, the sensitivity as a sensor becomes higher.

[0046] In addition, from the perspective of crosstalk suppression, the resonant frequencies may be different between the first signal output unit 31 and the second signal output unit 32. In addition, as disclosed in patent document 1 (WO2019 / 122867A1), the resonant frequencies may be different between multiple sensor units 30. In particular, the resonant frequencies may be different between sensor units 30 corresponding to adjacent keys 13. In addition, as disclosed in patent document 1 (WO2019 / 122867A1) and Japanese Patent Gazette No. 4375302, time division processing may be performed using a multiplexer and a demultiplexer when driving each sensor unit 30. For example, multiple sensor units 30 are grouped according to the key domain so that physically adjacent sensor units 30 are not driven at the same time. For example, the sensor units 30 in the low domain may be driven in sequence in each group one by one at the same time.

[0047] Figure 8 1 is a schematic front view of one key 13 and the corresponding sensor unit 30. The stroke position (position in the pressing direction) and the displacement in the front-rear direction of the key 13 are detected as follows.

[0048] First, when the key-side conductive portion 20 approaches the sensor portion 30 due to a key operation, as shown in FIG. Figure 2 As shown, the detection signals of the signal output units 31 and 32 are input to the adding unit 51 and the subtracting unit 52. The control unit 50 detects the stroke position of the key 13 based on the sum of the detection signals of the signal output units 31 and 32 input from the adding unit 51. At this time, for example, the smaller the sum of the signals is, the deeper the stroke position is detected.

[0049] In parallel with this, the control unit 50 detects the magnitude of the displacement in the front-rear direction of the key 13 based on the difference between the detection signals of the signal output units 31 and 32 input from the subtraction unit 52. At this time, the larger the difference in the signals, the larger the displacement in the front-rear direction is detected. Figure 8 As shown in FIG. 1 , if the key 13 is pressed and receives a forward force, the key 13 is displaced forward. In this case, the overlapping area of ​​the first conductive portion 21 and the first signal output portion 31 is larger than the overlapping area of ​​the second conductive portion 22 and the second signal output portion 32. Therefore, the first signal output portion 31 outputs a smaller detection signal than the second signal output portion 32, and the difference in the detection signals becomes larger.

[0050] As mentioned above, Figure 3 As shown in FIG. 1 , the interval between the straight lines L3 and L4 is larger than the interval between the straight lines L1 and L2. That is, the first signal output part 31 is offset to the front side relative to the first conductive part 21, and the second signal output part 32 is offset to the rear side (the opposite direction of the first signal output part 31) relative to the second conductive part 22. For example, it is conceivable that Figure 8 As shown, the key 13 is subjected to a force directed forward, and the key 13 is displaced to the front side in the horizontal direction. In this case, in the projection obtained by looking down, the overlapping area of ​​the first conductive part 21 and the first signal output part 31 is larger than the overlapping area of ​​the second conductive part 22 and the second signal output part 32. Therefore, the magnetic flux of the first conductive part 21 acting on the first signal output part 31 is stronger than the magnetic flux of the second conductive part 22 acting on the second signal output part 32. As a result, the first signal output part 31 outputs a detection signal smaller than the second signal output part 32, thereby increasing the difference in the detection signals. As a result, the control unit 50 can detect the situation in which the key 13 is displaced forward and the size of the displacement of the key 13 forward. In the case where the key 13 is displaced backward, the difference in the above-mentioned detection signals is reversed.

[0051] The offset arrangement increases the difference between the signal output units 31 and 32 when the key 13 is displaced in the front-rear direction, thereby increasing the sensitivity of detection related to the front-rear direction. The control unit 50 controls the sound effect based on the detected front-rear displacement.

[0052] In addition, the direction of the offset may be opposite to the illustrated direction. In addition, the offset configuration is not necessary, and the interval between the straight lines L1 and L2 may be the same as the interval between the straight lines L3 and L4, and the straight lines L1 and L2 may overlap with the straight lines L3 and L4. In this case, from the perspective of crosstalk suppression, it is preferred to configure the key side conductive portion 20 and the sensor portion 30 in a manner such that the center of gravity G1 is consistent with the center of gravity G3, and the center of gravity G2 is consistent with the center of gravity G4.

[0053] The control unit 50 detects the stroke position of the key 13 at any time during the key pressing and the key releasing. When the stroke position of the key 13 is deeper than the first predetermined position, the control unit 50 generates a note-on event and causes the sound generating unit 53 to start sounding. After the sound starts, the control unit 50 implements post-control of imparting effects such as vibrato based on the magnitude of the displacement in the detected front-to-back direction. For example, the greater the displacement in the front-to-back direction, the greater the degree of the effect imparted by the control unit 50 and the shorter the cycle. In addition, the detection result can be used for the control of effect imparting not only at the end of the key pressing of the key 13, but also during the key pressing and the key releasing.

[0054] In addition, when the stroke position of the key 13 is shallower than the second prescribed position (shallower than the first prescribed position) during the sound generation process, the control unit 50 starts to mute the sound generating unit 53. In addition, the control unit 50 detects the key pressing speed based on the time required for the key 13 to reach the first prescribed position from the third prescribed position (shallower than the first prescribed position) and uses it for sound control such as volume. Similarly, the key release speed can also be detected during the key release operation and used for sound control. In addition, the effect parameter to be controlled is not limited.

[0055] The above Figure 3 The arrangement shown can be applied to any of the white keys and the black keys, but it is difficult to realize if the key width is narrow. Figure 3 The configuration shown is for white keys. Fig. 9 The arrangement of black keys suitable for narrow key widths is described in detail.

[0056] Fig. 9 2 is a schematic plan view showing a configuration example of the key-side conductive portion 20 and the sensor portion 30. Fig. 9 In FIG. 1 , the key-side conductive portion 20 is shown as a projection diagram obtained by a plan view. Fig. 9 The first conductive portion 21, the second conductive portion 22, the first signal output portion 31, and the second signal output portion 32 are each configured similarly to those in Figure 3 The structure is the same as described in .

[0057] like Fig. 9 As shown, the conductive parts 21 and 22 are arranged in a straight line in the key length direction (front-back direction). The signal output parts 31 and 32 are also arranged in the key length direction. In the front-back direction (Y direction), the conductive parts 22 and 32 are closer to the fulcrum 12 than the conductive parts 21 and 31. On the other hand, compared with the interval L5 between the first conductive part 21 and the second conductive part 22 in the front-back direction, the interval L6 between the first signal output part 31 and the second signal output part 32 is larger. That is, the first signal output part 31 is offset to the front side relative to the first conductive part 21, and the second signal output part 32 is offset to the rear side relative to the second conductive part 22. In addition, the intervals L5 and L6 can also be defined as the intervals between the centers of gravity of the conductive parts and the intervals between the centers of gravity of the signal output parts. In addition, in the white keys, it is also possible to adopt Fig. 9 Configuration shown.

[0058] According to the present embodiment, a key side conductive portion 20 is provided as a pair of conductive portions on each of the plurality of keys 13. A sensor portion 30 (a pair of signal output portions 31, 32) is provided on the circuit substrate 15 corresponding to each key 13. The sensor portion 30 outputs a signal corresponding to the distance between the corresponding key 13 and the side conductive portion 20. The control portion 50 obtains the signal output from the sensor portion 30, and detects the position of the corresponding key 13 in the pressing direction and the displacement of the corresponding key 13 in the front-to-back direction based on the obtained signal. For example, the control portion 50 detects the stroke of the key 13 based on the sum of the signals respectively output from the signal output portions 31, 32, and detects the displacement of the key 13 in the front-to-back direction based on the difference between the signals respectively output. Thus, it is possible to detect not only the position of the key 13 in the pressing direction but also the displacement in the front-to-back direction based on the output of the same (common) signal output portions 31, 32.

[0059] In particular, it is possible to Figure 3 , Fig. 9 The offset arrangement shown can detect the displacement of the key 13 in the front-rear direction with high accuracy.

[0060] Furthermore, in each of the key-side conductive portion 20 and the sensor portion 30 , the spiral directions of two spiral portions adjacent to each other with the center as a base point are the same, so that crosstalk can be suppressed.

[0061] In addition, the stroke position detection does not necessarily require the use of the sum of the signals, and the stroke position may be detected using only one of the pair of signal output units 31 and 32 .

[0062] (Second embodiment)

[0063] In the first embodiment, the position of the key 13 in the pressing direction and the displacement in the front-rear direction are detected based on the signal output from the sensor unit 30. In the second embodiment of the present invention, in addition to the above, the displacement in the yaw direction or the roll direction of the key 13 can also be detected.

[0064] First, the key 13 is displaced mainly in the pitch direction, and strictly speaking, it is also displaced in the yaw direction and the roll direction. That is, the key 13 is subjected to a force in the left-right direction, and may also be displaced in the yaw direction. In addition, the key 13 is subjected to a force in the left-right direction, or is pressed near the end position in the width direction, so that the key 13 can be displaced in the direction of rotation (roll direction) centered on the axis along the length direction. In addition, the key 13 is mainly displaced in the pitch direction, but the structure of the key 13 can also be designed to be a structure that produces displacement in the roll direction and the yaw direction, as disclosed in Japanese Patent Gazette No. 4375302.

[0065] Fig.10 , Fig.11 It is a schematic plan view showing first and second structural examples of the key-side conductive portion 20 and the sensor portion 30 according to the second embodiment. Fig.12 , Fig.13 It is a schematic front view of one key 13 and the sensor unit 30 corresponding thereto in the first structural example.

[0066] exist Figure 10 to Figure 13 In the figure, the conductive parts A1 and A2 are Fig. 9 The conductive parts 21 and 22 shown in FIG. 1 are constructed in the same manner. The conductive parts A3 and A4 are also constructed in the same manner. Fig. 9 The conductive parts 21 and 22 shown in FIG. 1 are similarly configured. The signal output parts B1 and B2 are Fig. 9 The signal output units 31 and 32 shown in FIG. 1 are configured similarly. The signal output units B3 and B4 are configured similarly to the signal output units B4 and B5. Fig. 9 The signal output units 31 and 32 shown are constructed similarly. Fig.10 , Fig.11 In any of the first and second structural examples, the conductive parts A1 to A4 are shown as projections obtained by top view (planar view). In the front-to-back direction (Y direction), the conductive parts A2 and the signal output part B2 are closer to the fulcrum 12 than the conductive parts A1 and the signal output part B1.

[0067] In the first and second structural examples ( Fig.10 , Fig.11 ), the conductive parts A1 to A4 are offset in two directions, the front-rear direction and the key arrangement direction, relative to the signal output parts B1 to B4. Fig.10), in the key arrangement direction, the interval between the signal output parts B1 and B3 is larger than the interval between the conductive parts A1 and A3, and the interval between the signal output parts B2 and B4 is larger than the interval between the conductive parts A2 and A4. In the front-to-back direction, the interval between the signal output parts B1 and B2 is larger than the interval between the conductive parts A1 and A2, and the interval between the signal output parts B3 and B4 is larger than the interval between the conductive parts A3 and A4.

[0068] In the second structural example ( Fig.11 ), the signal output parts B1 to B4 are arranged in a straight line along the front-to-back direction. In the key arrangement direction, the conductive parts A1 and A3 are offset to the opposite sides of each other across the signal output parts B1 and B3, and the conductive parts A2 and A4 are offset to the opposite sides of each other across the signal output parts B2 and B4. In the front-to-back direction, the interval between the signal output parts B1 and B2 is larger than the interval between the conductive parts A1 and A2, and the interval between the signal output parts B3 and B4 is larger than the interval between the conductive parts A3 and A4.

[0069] Taking the first structural example ( Fig.10 ) as an example, the detection method of the stroke position, the displacement in the front-to-back direction and the yaw (displacement in the yaw direction or the rolling direction) of the key 13 is described.

[0070] First, for the detection of the stroke position and displacement in the front-to-back direction of the key 13, the combination of "the conductive part A1 and the signal output part B1" and "the conductive part A2 and the signal output part B2" is used. That is, the control part 50 detects the stroke position of the key 13 based on the sum of the detection signals of the signal output parts B1 and B2. In addition, the control part 50 detects the magnitude of the displacement in the front-to-back direction of the key 13 based on the difference between the detection signals of the signal output parts B1 and B2. In addition, for the detection of the stroke position and displacement in the front-to-back direction of the key 13, the combination of "the conductive part A3 and the signal output part B3" and "the conductive part A4 and the signal output part B4" can also be used.

[0071] Next, for the detection of the yaw, the combination of "the conductive part A1 and the signal output part B1" and "the conductive part A3 and the signal output part B3" is used. That is, the control part 50 detects the magnitude of the yaw of the key 13 based on the difference between the detection signals of the signal output parts B1 and B3 input from the subtraction part 52. At this time, the larger the difference between the signals, the larger the yaw is detected. If the signal output parts B1 and B2 are set as a pair of signal output parts for detecting the stroke position and the displacement in the front-rear direction, the signal output parts B1 and B3 are equivalent to another pair of signal output parts for detecting the yaw.

[0072] like Fig.12As shown, if the right part of the key surface of the key 13 is pressed down, the key 13 rolls to the right. In this case, the distance between the conductive part A1 and the signal output part B1 is shorter than the distance between the conductive part A3 and the signal output part B3. Therefore, the signal output part B1 outputs a smaller detection signal than the signal output part B3, so the difference in the detection signal becomes larger. As a result, the control unit 50 can detect the rolling direction of the key 13 and the size of the rolling displacement.

[0073] In addition, as described above, the interval between the signal output parts B1 and B3 is wider than the interval between the conductive parts A1 and A3. Fig.13 As shown, if the key 13 is subjected to a force to the right, the key 13 is displaced on the right side in the horizontal direction. In this case, in the projection obtained by looking down, the overlapping area of ​​the conductive part A1 and the signal output part B1 is larger than the overlapping area of ​​the conductive part A3 and the signal output part B3. Therefore, the magnetic flux of the conductive part A1 acting on the signal output part B1 is stronger than the magnetic flux of the conductive part A3 acting on the signal output part B3. As a result, the signal output part B1 outputs a smaller detection signal than the signal output part B2, so the difference in the detection signal becomes larger. As a result, the control unit 50 is able to detect the magnitude of the displacement of the key 13 in the deflection direction. By the offset configuration as described above, the difference between the signal output parts B1 and B3 when the key 13 is displaced in the horizontal direction becomes larger, so the sensitivity of the detection related to the deflection direction becomes higher.

[0074] Furthermore, the displacement in the yaw direction and the roll direction (so-called yaw) is generated in a complex manner, and it is difficult for the performer to be aware of both and to perform the performance. In the detection, it is not very meaningful to distinguish between the two. Therefore, the control unit 50 can also capture both in a complex manner and detect them as yaw, which is beneficial to effect control. However, yaw can be detected not only at the end of the key press, but also in the middle of the key press and the middle of the key release.

[0075] Furthermore, when detecting yaw, it is also possible to determine whether the yaw is mainly caused by rolling displacement or deflection displacement based on the difference between the difference between the signal output parts B1 and B3 and the difference between the signal output parts B2 and B4. For example, in the key arrangement direction, if the key front end is displaced more than the key rear end, and the difference is large, it can be determined that the yaw is mainly caused by deflection displacement. In addition, for the detection of yaw, the combination of "conductive part A2 and signal output part B2" and "conductive part A4 and signal output part B4" can also be used.

[0076] In the second structural example ( Fig.11), the stroke position, displacement in the front-to-back direction, and yaw of the key 13 can be detected. For example, for the detection of the stroke position and displacement in the front-to-back direction of the key 13, the combination of "the conductive part A1 and the signal output part B1" and "the conductive part A2 and the signal output part B2" is used. Alternatively, the combination of "the conductive part A3 and the signal output part B3" and "the conductive part A4 and the signal output part B4" can be used. In addition, for the detection of yaw, the combination of "the conductive part A1 and the signal output part B1" and "the conductive part A3 and the signal output part B3" is used. Alternatively, the combination of "the conductive part A2 and the signal output part B2" and "the conductive part A4 and the signal output part B4" can be used.

[0077] According to this embodiment, not only the position of the key 13 in the pressing direction but also the displacement in the front-back direction can be detected based on the output of the same (common) signal output unit, and the same effect as the first embodiment can be achieved. In addition, the displacement in the deflection direction or the rolling direction of the key can be detected in the middle of the key pressing based on the output of the same (common) signal output unit.

[0078] In addition, in the first structural example ( Fig.10 )、Second structural example ( Fig.11 ), the two spiral parts of the conductive parts A1 to A4 and the signal output parts B1 to B4 are arranged in the front-to-back direction. However, the two spiral parts of the conductive parts A1 to A4 and the signal output parts B1 to B4 may also be arranged in the key arrangement direction.

[0079] In addition, in this embodiment, the sensor parts used for the detection of the stroke position, the displacement in the front-back direction, and the yaw detection can be common, so the structure is simple and there is no need to set up an optical sensor. However, in order to detect the stroke position and the key speed, an optical or contact position sensor or a speed sensor may be separately provided. In addition, it is not necessary to detect the stroke position by a pair of signal output parts.

[0080] Below, in Fig.14 , Fig.15 , modifications of the above-mentioned embodiments are described. Fig.14 2 is a schematic plan view showing a configuration example of a first modified example of the key-side conductive portion 20 and the sensor portion 30. Fig.14 In the example shown, relative to Figure 3In the example shown, the winding directions of the winding parts 23 and 24 of the first conductive part 21 are opposite. Therefore, the swirl directions of the winding parts adjacent to each other in the front-back direction, that is, the winding part 23 of the first conductive part 21 and the winding part 25 of the second conductive part 22, with the center as the base point are opposite to each other. Similarly, the swirl directions of the winding part 24 and the winding part 26 adjacent to each other in the front-back direction with the center as the base point are also opposite to each other.

[0081] In addition, similarly, Fig.14 In the example shown, relative to Figure 3 In the example shown, the winding portions adjacent to each other in the front-to-back direction, i.e., the winding portions 33 and 34 of the first signal output portion 31, have opposite winding directions. Therefore, the vortex directions of the winding portions 33 and 35 adjacent to each other in the front-to-back direction with the center as the base point are opposite to each other. Similarly, the vortex directions of the winding portions 34 and 36 adjacent to each other in the front-to-back direction with the center as the base point are opposite to each other. As described above, in each of the key side conductive portion 20 and the sensor portion 30, the vortex directions of the winding portions adjacent to each other in the front-to-back direction with the center as the base point are opposite to each other. With this structure, the directions of the magnetic flux generated are opposite not only in the key arrangement direction but also between the winding portions adjacent to each other in the key length direction, which is more conducive to suppressing crosstalk.

[0082] In addition, in the above embodiments, the conductive parts 21, 22 and the signal output parts 31, 32 are not necessarily parallel to the key arrangement direction or the key length direction. The conductive parts and the corresponding signal output parts can be inclined in the same direction, but they do not have to be inclined in the same direction.

[0083] Fig.15 2 is a schematic top view showing a configuration example of a second modified example of the key-side conductive portion 20 and the sensor portion 30. Fig.15 As shown, the conductive parts 21, 22 (or conductive parts A1 to A4) and the signal output parts 31, 32 (or signal output parts B1 to B4) may be each formed by a coil composed of a single vortex instead of two vortices. In addition, only the group of the conductive part 21 and the signal output part 31 or the group of the conductive part 22 and the signal output part 32 may be formed as a group of coils composed of a single vortex.

[0084] In addition, the key-side conductive portion is preferably an inductive element, and is not limited to an induction coil, and a conductive component can also be used for the key-side conductive portion. For example, with respect to the key-side conductive portion, as shown as the key-side conductive portion 20-2, a conductive metal plate 54, 55 can be provided instead of the conductive portion 21, 22. The metal plates 54, 55 are made of iron or the like. The metal plates 54, 55 are plate components that are approximately parallel to the key surface. If the distance of the metal plates 54, 55 relative to the signal output portions 31, 32 changes, the capacitance of the signal output portions 31, 32 changes, thereby being able to extract a signal of a size corresponding to the distance.

[0085] Alternatively, as shown as the key-side conductive portion 20-3, a metal plate 56 having the same conductivity as the metal plates 54 and 55 may be provided instead of the conductive portions 21 and 22. In addition, when the key-side conductive portion 20-2 or the key-side conductive portion 20-3 is used, the coil shape of the signal output portion 31 and 32 may be either two spirals or a single spiral.

[0086] In addition, the parallel movement of the key in the horizontal direction or the up-down direction can also be detected based on the output of the same (common) signal output unit. For example, in a keyboard configured so that the key as a whole can be displaced in parallel in the key arrangement direction, it can also be configured so that the parallel movement of the key in the key arrangement direction can be detected. Alternatively, in a keyboard configured so that the key as a whole can be displaced in parallel in the up-down direction, it can also be configured so that the parallel movement of the key in the up-down direction can be detected. At this time, it is also possible to detect the parallel movement of the key in the horizontal direction or the up-down direction on the basis of the detection objects illustrated in the above-mentioned embodiments, or to replace the illustrated detection objects.

[0087] In addition, in each example including the above-mentioned modified example, the signal output unit that outputs a signal corresponding to the distance from the corresponding key-side conductive portion 20 can also be set to have more than two signal output units corresponding to multiple keys 13, not limited to two. For example, more than two pairs of signal output units can be set, and the displacement can be detected using the signals from each pair. Alternatively, three signal output units can be arranged, and the signal output unit in the middle is set to be dedicated to the detection of the stroke position.

[0088] Furthermore, the key operation detection device of the present invention does not necessarily need to be able to detect operations on all the keys 13 of the keyboard device 100 , and may detect only some of the keys 13 .

[0089] The spiral-shaped portions of the coils C21 and C31 constituting the conductive portions 21 and 22 and the signal output portions 31 and 32 may be not limited to circular shapes, but may be oval or rectangular shapes. The coils C21 and C31 are planar shapes, but need not be limited to planar shapes if the configuration space allows.

[0090] Furthermore, the present invention is not limited to the keyboard device 100 , but can also be applied to a pedal, a keyboard for a personal computer, and the like.

[0091] In addition, in this embodiment, the content added with "approximately" does not mean to exclude completely. For example, "approximately parallel" and "approximately circular" mean to include parallel and circular, respectively.

[0092] The present invention has been described in detail based on its preferred embodiments above, but the present invention is not limited to the above-mentioned specific embodiments, and various modes that do not deviate from the scope of the present invention are also included in the present invention. Parts of the above-mentioned embodiments may also be appropriately combined.

[0093] This application is based on the Japanese application (Japanese Patent Application No. 2020-085055) filed on May 14, 2020, the contents of which are incorporated herein by reference.

[0094] Description of the label

[0095] 13 keys

[0096] 15 Circuit board

[0097] 20 Key side conductive part

[0098] 21, 22 Conductive part

[0099] 31, 32 Signal output unit

[0100] 30 Sensor unit

[0101] 50 Control Department

[0102] 101 Operation detection device

Claims

1. A device for detecting key operation of a keyboard device, comprising: a conductive portion provided on each of the plurality of keys; A substrate, which is arranged to be opposite to the plurality of keys in a pressing direction of the plurality of keys; at least one pair of signal output parts, each having a coil, provided on the substrate corresponding to one of the plurality of keys, and outputting a signal corresponding to a distance between the signal output part and the conductive part provided on the corresponding key; and A detection unit detects the position of the corresponding key in the pressing direction based on the sum of the signals outputted from the pair of signal output units, and detects the displacement of the corresponding key in the front-to-back direction, i.e., the length direction of the key, based on the difference between the signals outputted from the pair of signal output units.

2. The key operation detection device of the keyboard device according to claim 1, wherein: The pair of signal output parts are arranged side by side in the front-rear direction of the key.

3. The key operation detection device of the keyboard device according to claim 2, wherein: The first signal output portion of the pair of signal output portions is arranged to be offset in a first direction in the front-rear direction relative to the conductive portion. The second signal output portion of the pair of signal output portions is arranged to be offset with respect to the conductive portion in a second direction, which is a direction opposite to the first direction of the first signal output portion in a front-rear direction.

4. The key operation detection device of the keyboard device according to any one of claims 1 to 3, wherein: The coils of the signal output parts each have two spiral parts adjacent to and connected to each other. The two spiral portions have the same spiral directions with their respective centers as base points.

5. The key operation detection device of the keyboard device according to any one of claims 1 to 3, wherein: The conductive portion is a metal plate that is approximately parallel to a surface of the corresponding key.

6. The key operation detection device of the keyboard device according to any one of claims 1 to 3, wherein: The conductive part is a circuit having a coil formed by connecting two spiral parts. The two spiral portions of the conductive portion have spiral directions that are the same with respect to their respective centers.

7. The key operation detection device of the keyboard device according to claim 2, wherein: The signal output unit includes another pair of signal output units arranged in a key arrangement direction corresponding to each of the plurality of keys. The detection unit detects displacement of the corresponding key in at least one of a deflection direction and a rollover direction based on a difference between the signals outputted from the other pair of signal output units.

8. A keyboard device, comprising: The key operation detection device according to any one of claims 1 to 7; and The plurality of keys.

9. A method for detecting key operation of a keyboard device, the keyboard device comprising: a conductive portion provided on each of a plurality of keys; a substrate provided opposite to the plurality of keys in a direction in which the plurality of keys are pressed; and at least one pair of signal output portions, each of which has a coil, provided on the substrate corresponding to one of the plurality of keys, and outputting a signal corresponding to the following distance, the distance being the distance between the signal output portion and the conductive portion provided on the corresponding key, In the method for detecting key operation of the keyboard device, obtaining a signal output from the at least one pair of signal output units, The position of the corresponding key in the pressing direction is detected based on the sum of the signals outputted from the pair of signal output parts, and the displacement of the corresponding key in the front-to-back direction, i.e., the length direction of the key is detected based on the difference between the signals outputted from the pair of signal output parts.

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