Keyboard device and method for forming magnetic shield

Abstract

The magnetic shield 82a and the magnetic shield 82b are formed by the conductor pattern of the substrate 8, so that the magnetic shield 82a and the magnetic shield 82b can be formed to be thin. Therefore, even if the displacement member (7) (detected part (75)) is displaced substantially parallel to the substrate (8), the interference of the magnetic shield (82a, 82b) to the displacement of the displacement member (7) can be suppressed, and the key information can be detected on the basis of the increase and decrease in the inductance of the coil (80). Furthermore, even if the displacement member (7) (the detected part (75)) is vertically displaced with respect to the substrate (8), the key information can be detected on the basis of the increase and decrease in the inductance of the coil (80). Therefore, the degree of freedom of design of the keyboard device 1 is improved. Further, by forming the magnetic shield (82a, 82b) thin by means of the conductor pattern, restrictions on the arrangement of the substrate (8) can be suppressed. As a result, the degree of freedom of design of the keyboard device (1) is also improved.

Description

Technical Field

[0001] The present invention relates to a keyboard device and a method for forming a magnetic shielding member, and in particular to a keyboard device and a method for forming a magnetic shielding member capable of improving the degree of freedom in design. Background Art

[0002] For example, Patent Document 1 describes a technique in which a coil that forms a magnetic field is provided on a magnetic detection circuit 12 (substrate), and a magnet 8 is relatively displaced relative to the magnetic detection circuit 12 (coil) when a key 2 is pressed. According to the technique, the coil generates an electromotive force corresponding to the distance or speed of the magnet 8 relative to the magnetic detection circuit 12, and thus the depth or speed of the key press (hereinafter referred to as "key press information") can be detected by the electromotive force.

[0003] Furthermore, in Patent Document 1, interference of magnetic fields between adjacent coils is suppressed by partitioning (enclosing) each magnetic detection circuit 12 arranged in the scale direction with a shield frame 14. By suppressing such interference of magnetic fields, key information of each key 2 can be detected with good accuracy.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Utility Model Publication No. 02-111199 (for example, page 6, line 3 to page 7, line 4 and page 9, line 2 to line 7, Figure 1 ) Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, in the prior art, the shielding frame 14 is formed in the shape of a wall rising from the magnetic detection circuit 12. Therefore, in order to detect the key information based on the displacement of the magnet 8, it is necessary to displace the magnet 8 vertically (up and down) relative to the magnetic detection circuit 12. Therefore, for example, it is impossible to displace the magnet 8 parallel to the magnetic detection circuit 12 (in the horizontal direction), which is likely to restrict the structure of the keyboard device. In addition, it is necessary to ensure the configuration space of the shielding frame 14 rising from the magnetic detection circuit 12, which is also likely to restrict the structure of the keyboard device. That is, in the prior art, by providing the shielding frame 14, although the interference of the magnetic field of the adjacent coils can be suppressed, there is a problem that the design freedom of the keyboard device is low.

[0009] The present invention is made to solve the above-mentioned problems, and an object of the present invention is to provide a keyboard device and a method for forming a magnetic shield that can improve the degree of freedom in design.

[0010] Technical means of solving problems

[0011] In order to achieve the above-mentioned purpose, the keyboard device of the present invention includes: a plurality of displacement members arranged in the scale direction and displaced along with the operation of the performer; and a substrate having coils for generating a magnetic field for detecting the displacement of these plurality of displacement members, the substrate including: a plurality of the coils provided for each of the plurality of the displacement members; and a magnetic shielding member dividing these plurality of the coils from each other and formed by the conductive pattern of the substrate.

[0012] The method for forming a magnetic shield of the present invention is a method for forming a magnetic shield in a keyboard device, the keyboard device comprising: a plurality of displacement members arranged in a scale direction and displaced in response to a performer's operation; and a substrate having coils for generating a magnetic field for detecting the displacement of the plurality of displacement members, the substrate comprising: a plurality of the coils provided for each of the plurality of displacement members; and a magnetic shield for dividing the plurality of coils from each other, wherein the magnetic shield is formed by a conductive pattern of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] [ Figure 1 ] is a cross-sectional view of the keyboard device of the first embodiment.

[0014] [ Figure 2 (a) Yes Figure 1 (b) is a partially enlarged cross-sectional view of the keyboard device of part IIa of Figure 2 (a) is a partially enlarged cross-sectional view of the keyboard device taken along line IIb-IIb.

[0015] [ Figure 3 (a) Yes Figure 2 (b) is a partially enlarged cross-sectional view of the substrate of part IIIa, (b) is Figure 3 (a) is a top view of the substrate when viewed in the direction of arrow IIIb.

[0016] [ Figure 4 ](a) is a partially enlarged cross-sectional view of a substrate of the second embodiment, (b) is a partially enlarged cross-sectional view of a substrate of the third embodiment, and (c) is a partially enlarged cross-sectional view of a substrate of the fourth embodiment.

[0017] [ Figure 5 ](a) is a top view of the substrate of the fifth embodiment, and (b) is a top view of the substrate of the sixth embodiment.

[0018] [ Figure 6 ](a) is a top view of the substrate of the seventh embodiment, and (b) is a top view of the substrate of the eighth embodiment. DETAILED DESCRIPTION

[0019] Hereinafter, preferred embodiments will be described with reference to the accompanying drawings. Figure 1 , the overall structure of the keyboard device 1 according to the first embodiment will be described. Figure 1 is a cross-sectional view of the keyboard device 1 according to the first embodiment. Figure 1 , a cross section obtained by cutting the keyboard device 1 along a plane perpendicular to the scale direction (the arrangement direction of the plurality of keys 2) is shown. Figure 1 The left side of the keyboard device 1 is recorded as the front side of the keyboard device 1, and the opposite side ( Figure 1 The right side of the key 2 is recorded as the rear side, and the arrangement direction of the plurality of keys 2 ( Figure 1 The direction perpendicular to the paper surface) is recorded as the scale direction for explanation.

[0020] like Figure 1 As shown, the keyboard device 1 is a keyboard musical instrument (synthesizer) including a plurality of keys 2. The keys 2 include a plurality of (52 in this embodiment) white keys 2a for playing natural sounds and a plurality of (36 in this embodiment) black keys 2b for playing altered sounds. The plurality of white keys 2a and black keys 2b are arranged in a scale direction ( Figure 1 In addition, in the present embodiment, a total of 88 keys 2 are provided, but a structure in which 76 or 61 keys 2 are provided may also be provided.

[0021] The keyboard device 1 includes a bottom plate 3 for supporting the white keys 2a and the black keys 2b. The bottom plate 3 is formed into a flat plate extending in the scale direction using synthetic resin, wood, steel plate, etc., and a chassis 4 is supported on the upper surface of the bottom plate 3.

[0022] The chassis 4 includes Figure 1 A pair of legs 40 are provided at a predetermined interval in the left-right direction of the support portion 41, and the upper ends of the pair of legs 40 are connected to each other front and back. The legs 40 and the support portion 41 are integrally formed using synthetic resin, wood, steel plate, etc., and the rear end side ( Figure 1 A supporting member 5 for rotatably supporting the key 2 is provided on the upper surface of the key 2 (on the right side).

[0023] Hereinafter, a support structure for supporting the white key 2a by the support member 5 and a structure for rotating the displacement member 7 via the white key 2a will be described, but these structures are substantially the same also in the black key 2b.

[0024] The support member 5 includes a mounted portion 50 mounted on the upper surface of the chassis 4 (support portion 41), a wall portion 51 rising upward from the mounted portion 50, and a cylindrical shaft portion 52 formed on the upper end side of the wall portion 51. These portions 50 to 52 are integrally formed using a resin material (synthetic resin).

[0025] Although not shown in the figure, the mounted portion 50 is formed in a plate shape extending in the scale direction, and a plurality of wall portions 51 are arranged in the scale direction. In the space between the plurality of wall portions 51, the rear end portion of the white key 2a is rotatably supported by the shaft portion 52.

[0026] On the front end side of the mounted portion 50 ( Figure 1 The upper surface of the left end portion of the coil spring 6 is formed with a cylindrical retaining wall 53 for retaining the coil spring 6, and a plurality of retaining walls 53 are arranged in the scale direction. In the central portion of the inner circumference of each retaining wall 53, a conical convex portion 54 protruding upward is formed.

[0027] A recess 20 is formed on the lower surface of the white key 2a at a position facing the holding wall 53 from top to bottom, and a conical convex portion 21 protruding downward is formed on the inner circumference of the recess 20. The coil spring 6 is held by the holding wall 53 and the inner circumference of the recess 20 by clamping the coil spring 6 from top to bottom using the convex portion 54 of the support member 5 and the convex portion 21 of the white key 2a.

[0028] When the white key 2a is pressed, the elastic force of the coil spring 6 provides a key touch. On the other hand, when the white key 2a is released after being pressed, the white key 2a returns to its initial position due to the elastic restoring force of the coil spring 6. When the white key 2a is pressed and released, the displacement member 7 is linked to the rotation of the white key 2a around the shaft 52, and the displacement of the displacement member 7 is controlled by the coil 80 of the substrate 8 (see Figure 2 ) detection.

[0029] Reference Figure 2 A detailed structure for detecting the displacement of the displacement member 7 will be described below. Figure 2 (a) Yes Figure 1 A partial enlarged cross-sectional view of the keyboard device 1 of part IIa, Figure 2 (b) Yes Figure 2 (a) is a partially enlarged cross-sectional view of the keyboard device 1 along line IIb-IIb. Figure 2 In (b), some structures (white keys 2a, bottom plate 3, etc.) are omitted from illustration, only the main part of the keyboard device 1 is illustrated, and hatching of the base plate 8 is omitted.

[0030] like Figure 2 As shown, the bottom plate 3 is fixed with a Figure 2(b) The plate-shaped substrate 8 extends in the left-right direction of the key 2, and a plurality of coils 80 are arranged in the scale direction on the substrate 8. The coils 80 generate a magnetic field for detecting the displacement of the displacement member 7 provided for each of the plurality of keys 2, as will be described in detail later.

[0031] The displacement member 7 is rotatably supported by the holder 9 above each coil 80. The holder 9 includes a mounted portion 90 mounted on the upper surface of the substrate 8, and the mounted portion 90 is formed in a plate shape extending in the scale direction.

[0032] A plurality of wall portions 91 arranged in the scale direction stand upward from the mounted portion 90, and a cylindrical shaft portion 92 for axially supporting the displacement member 7 is formed on the upper end side of the wall portion 91. The respective portions 90 to 92 of the retainer 9 are integrally formed using a resin material (synthetic resin).

[0033] The mounted portion 90 is provided with a plurality of through holes 93 arranged in the scale direction, and these plurality of through holes 93 are formed at positions corresponding to the coils 80. The shaft portions 92 protrude from a pair of wall portions 91 facing each other across the through holes 93 toward the opposing spaces, and the insertion holes 70 for inserting the shaft portions 92 penetrate the displacement member 7 in the scale direction. Although not shown in the figure, the shaft portions 92 can be inserted into the insertion holes 70 of the displacement member 7 by elastically deforming the wall portions 91 (mounted portion 90) to expand the interval between the facing shaft portions 92. The displacement member 7 is rotatably supported by the shaft portions 92 at a position facing each other up and down with the coils 80 (through holes 93).

[0034] The bottom surface 71 of the displacement member 7 (the surface facing the coil 80 when the displacement is caused by the key) is formed in an arc shape with the insertion hole 70 (the shaft portion 92) as the center. The two ends of the bottom surface 71 in the rotation direction of the displacement member 7 around the shaft portion 92 are connected to the front side ( Figure 2 (a) the front surface 72 of the displacement member 7 and the rear side ( Figure 2 The groove 74 extends from the rear surface 73 of the displacement member 7 toward the front side of the displacement direction of the displacement member 7 ( Figure 2 The lower left of (a) extends in a straight line.

[0035] The protrusion 22 protrudes downward from the lower surface of the white key 2a, and the cylindrical guide pin 23 protrudes in the scale direction from the side surface of the protrusion 22. These protrusions 22 and guide pins 23 are formed integrally with the white key 2a, but the protrusions 22 and guide pins 23 may be formed separately from the white key 2a (the protrusions 22 are embedded in the white key 2a).

[0036] The guide pin 23 is slidably engaged with the groove 74 of the displacement member 7, and the groove 74 is arranged so as to be slidable with the guide pin 23 around the shaft portion 52 (see Figure 1 Therefore, although the figure is omitted, when the white key 2a is pressed, if the guide pin 23 is rotated around the shaft portion 52 (refer to Figure 1 ) is rotated, the groove 74 is pressed into the guide pin 23, and the displacement member 7 is moved around the shaft portion 92 ( Figure 2 (a) clockwise rotation).

[0037] By the rotation of the displacement member 7, the detected portion 75 provided on the bottom surface 71 and the front surface 72 of the displacement member 7 is relatively displaced with respect to the coil 80 of the substrate 8. That is, as the stroke amount of the white key 2a increases from the state before the key is pressed, the intrusion amount of the detected portion 75 into the area facing the coil 80 (hereinafter referred to as the "detection area") increases. The so-called intrusion amount of the detected portion 75 refers to the size of the area facing the detected portion 75 and the coil 80 in the thickness direction of the substrate 8.

[0038] On the other hand, when the white key 2a is released, the coil spring 6 (see Figure 1 ) elastic restoring force, the guide pin 23 rotates around the shaft portion 52 (refer to Figure 1 ) is rotated. The guide pin 23 rotates, and the groove 74 is pushed up by the guide pin 23, thereby the displacement member 7 is moved around the shaft portion 92 ( Figure 2 As the detected portion 75 rotates counterclockwise (in the direction of FIG. 1 ), the amount of intrusion of the detected portion 75 into the detection area decreases.

[0039] The detected portion 75 is a conductor formed of a conductive material (copper, etc.), so when a current flows through the coil 80 to generate a magnetic field, if the amount of intrusion of the detected portion 75 into the detection area increases, the inductance of the coil 80 decreases, and if the amount of intrusion of the detected portion 75 into the detection area decreases, the inductance of the coil 80 increases. The key information (note information) of each key 2 is detected based on the increase or decrease in the inductance of the coil 80.

[0040] Then, refer to Figure 3 The detailed structure of the substrate 8 will be described. Figure 3 (a) Yes Figure 2 (b) is a partially enlarged cross-sectional view of the substrate 8 in part IIIa, Figure 3 (b) Yes Figure 3 (a) is a top view of the substrate 8 when viewed in the direction of arrow IIIb. Figure 3 In FIG. 8 , the cross-sectional structure of the substrate 8 is schematically illustrated, while the resist covering the coil 80 and the magnetic shield 82a and 82b is omitted. Figure 3In (a), the cross-sections of the coil 80 and the magnetic shield 82a and 82b are marked with dotted hatching. Figure 3 In (b), the formation area of ​​the magnetic shield 82a when the substrate 8 is viewed from above is indicated by dotted hatching. Figures 4 to 6 ) is also the same.

[0041] like Figure 3 As shown, the substrate 8 is a multilayer substrate (multilayer printed wiring board) having a plurality of (three in this embodiment) laminated plates 81a to 81c laminated. Among the laminated plates 81a to 81c, laminated plates 81a and 81c are laminated on the front and back of the substrate 8, and laminated plate 81b is laminated between them.

[0042] The coil 80 includes a coil 80a stacked on the upper surface of the laminated plate 81a (the outer layer on the surface side of the substrate 8), a coil 80b and a coil 80c stacked on the inner layer between the laminated plates 81a to 81c, and a coil 80d stacked on the lower surface of the laminated plate 81c (the outer layer on the back side of the substrate 8). Figure 3 In (b)), the coil 80 (coil 80a to coil 80d) is formed in a rectangular shape, but a circular coil 80 may also be used.

[0043] When manufacturing the coils 80a to 80d stacked in this way, first, the copper foils on both sides of the laminate 81b (copper-clad laminate with copper foils on both sides) are etched to form the coils 80b and 80c. Then, the copper foils of the laminate 81a and 81c (copper-clad laminate with copper foils on one side) are etched to form the coils 80a and 80d, and the laminates 81a to 81c are overlapped in such a manner that the coils 80a and 80d are arranged on the front and back of the substrate 8. Thus, the substrate 8 stacked with the coils 80a to 80d (conductor layers) and the laminates 81a to 81c (insulating layers) is manufactured.

[0044] That is, each coil 80 of the substrate 8 is formed by the conductor pattern of the substrate 8. In the following description, the case where the coil 80 is formed by etching of such a copper foil is simply described as "formed by the conductor pattern of the substrate 8" and the like.

[0045] The coil 80 formed by the conductor pattern is in the scale direction ( Figure 3 The coils 80 are arranged in the left and right directions, but these coils 80 are divided by magnetic shielding members 82a and 82b as conductors. Thus, the magnetic fields of the coils 80 adjacent to each other in the scale direction can be suppressed from interfering with each other. By suppressing such magnetic field interference (reducing the mutual inductance between adjacent coils 80), the key information of each key 2 can be detected with good accuracy.

[0046] The magnetic shields 82a and 82b are formed of the conductor pattern of the substrate 8 in the same manner as the coil 80, so the magnetic shields 82a and 82b can be formed thin. Therefore, even if the displacement member 7 (detected portion 75) is displaced substantially parallel to the substrate 8 (see Figure 2 ), the magnetic shields 82a and 82b can be prevented from interfering with the displacement of the displacement member 7, and the key information can be detected based on the increase or decrease of the inductance of the coil 80. In addition, even if a structure equivalent to the detection portion 75 is provided in the key 2 as in the prior art (Japanese Utility Model Publication No. 02-111199), and the displacement member 7 (detection portion 75) is vertically displaced relative to the substrate 8, the key information can be detected based on the increase or decrease of the inductance of the coil 80. Therefore, the freedom of design of the keyboard device 1 is improved.

[0047] Furthermore, by making the magnetic shields 82a and 82b thinner by using the conductor pattern, it is possible to suppress restrictions on the arrangement of the substrate 8. This also improves the degree of freedom in designing the keyboard device 1.

[0048] The magnetic shields 82a and 82b are formed in a ring shape (a quadrilateral ring shape) surrounding the entire circumference of the coil 80 in a plan view (see Figure 3 (b)), it is possible to effectively suppress interference between magnetic fields of adjacent coils 80. Therefore, key information can be detected with high accuracy.

[0049] Here, when the current flowing in the coil 80 changes, the magnetic field generated by the coil 80 also changes. Due to the change in the magnetic field of the coil 80, an induced current is generated in the conductive magnetic shields 82a and 82b surrounding the coil 80. The magnetic fields of the magnetic shields 82a and 82b generated by the induced current are in the opposite direction to the magnetic field of the coil 80, so the magnetic field of the coil 80 is offset by the magnetic fields of the magnetic shields 82a and 82b, and the interference of the magnetic fields of the adjacent coils 80 can be suppressed.

[0050] For example, in the sixth embodiment described later (see Figure 5 When the magnetic shield 682 is connected to the ground as in (b), it is difficult to generate the magnetic field of the magnetic shield 82a and the magnetic shield 82b (the magnetic field that cancels the magnetic field of the coil 80). The reason is that when the magnetic shield 682 is connected to the ground, part of the induced current generated in the magnetic shield 682 flows to the ground (the current remaining in the magnetic shield 682 is reduced), and the intensity of the magnetic field generated in the magnetic shield 682 is reduced.

[0051] When the magnetic shield 682 is formed into a wide surface as in the sixth embodiment, the path of the induced current generated in the magnetic shield 682 becomes wider. When the path of the induced current becomes wider, a weak current flows widely in the magnetic shield 682, so the strength of the magnetic field of the magnetic shield 682 decreases.

[0052] That is, in a structure where the magnetic shield 682 is connected to the ground or is formed in a wide planar shape as in the sixth embodiment, the strength of the magnetic field of the magnetic shield 682 generated by the induced current, that is, the magnetic field that cancels the magnetic field of the coil 80, decreases, so the magnetic field of the adjacent coil 80 is easily interfered. Therefore, the detection accuracy of the key information decreases.

[0053] In contrast, the magnetic shields 82a and 82b of the present embodiment are not connected to the circuit constituting the substrate 8, such as the ground, and the magnetic shields 82a and 82b adjacent to each other in the scale direction are not connected to each other. That is, each magnetic shield 82a and 82b is in an electrically floating state in the substrate 8, so unlike the case where the magnetic shields 82a and 82b are connected to the ground as described above, a part of the induced current of the magnetic shields 82a and 82b can be suppressed from flowing to the ground. Therefore, the strength of the magnetic field of the magnetic shields 82a and 82b can be suppressed from decreasing.

[0054] Furthermore, since the magnetic shields 82a and 82b are formed in a linear shape, the path of the induced current generated in the magnetic shields 82a and 82b can be limited (strong current can flow in a relatively narrow range) compared to the case where the magnetic shields 82a and 82b are formed in a wide plane shape. This can also suppress the reduction in the strength of the magnetic field of the magnetic shields 82a and 82b.

[0055] That is, when the magnetic shields 82a and 82b are electrically floating and formed into a linear shape as in the present embodiment, the magnetic field of the coil 80 can be appropriately offset by the magnetic field generated by the magnetic shields 82a and 82b. As a result, interference of the magnetic fields of the adjacent coils 80 can be suppressed, so that the key information can be detected with good accuracy. In addition, the so-called linear shape means, for example, that the width dimension of the magnetic shields 82a and 82b is set to a dimension that is greater than 1% and less than 20% of the interval between the coils 80 in the scale direction.

[0056] In this way, in order to detect the key information with good accuracy, it is important to balance the enhancement of the magnetic field of the coil 80 (increasing the self-inductance) and the suppression of the interference of the magnetic fields between the coils 80 (reducing the mutual inductance). Therefore, in this embodiment, four layers of coils 80a to 80d are stacked on the substrate 8, and two layers of magnetic shields 82a and 82b are stacked on the substrate 8. Thus, the magnetic field can be enhanced by the multi-layer coils 80, and the interference of the magnetic fields between the coils 80 can be suppressed by the multi-layer magnetic shields 82a and 82b. Therefore, the key information can be detected with good accuracy.

[0057] When the coils 80a to 80d or the magnetic shields 82a and 82b are stacked in multiple layers, for example, the magnetic shields 82a and 82b may be provided on all the conductor layers of the substrate 8. That is, the magnetic shields 82a and 82b of the present embodiment are formed on the upper surface of the stacked plate 81a and the lower surface of the stacked plate 81c. In addition, the magnetic shields 82a and 82b may also be formed on the inner layer between the stacked plates 81a to 81c.

[0058] However, when the magnetic shields 82a and 82b are formed on all layers of the substrate 8, the detection accuracy of the key information tends to decrease (the mutual inductance of each coil 80 increases). This is believed to be because the magnetic shields 82a and 82b also generate magnetic fields due to the induced current, so if the magnetic shields 82a and 82b are excessively formed in multiple layers, the magnetic fields of the magnetic shields 82a and 82b are likely to interfere with the magnetic fields of the adjacent coils 80.

[0059] Therefore, in the present embodiment, a structure is adopted in which the magnetic shielding parts 82a and 82b are not stacked in the inner layer between each stacked plate 81a to 81c. That is, the number of stacking layers of the magnetic shielding parts 82a and 82b (two layers) is made less than the number of stacking layers of the coils 80a to 80d (four layers). As a result, the key information can be detected with good accuracy (the mutual inductance of each coil 80 is reduced). It is believed that the reason is that compared with the case where the magnetic shielding parts 82a and 82b are set on all layers of the substrate 8 as described above, the magnetic field generated by the magnetic shielding parts 82a and 82b is not easy to interfere with the magnetic field of the adjacent coil 80.

[0060] In this way, it is considered that the detection accuracy of the key information is also affected by the magnetic field generated by the magnetic shielding members 82a and 82b. Figure 4If the magnetic shields 82a (magnetic shields 82b) adjacent to each other in the musical scale direction are stacked in different layers as in (a), the interference of the magnetic field from the magnetic shields 82a and 82b is received differently in each coil 80. Therefore, in each coil 80 arranged in the musical scale direction, the increase or decrease of the inductance accompanying the pressing or releasing of a key may cause a deviation.

[0061] In contrast, in the present embodiment, the magnetic shields 82a arranged in the musical scale direction are stacked on the same layer (the upper surface of the laminated plate 81a), and the magnetic shields 82b arranged in the musical scale direction are also stacked on the same layer (the lower surface of the laminated plate 81c). As a result, the manner in which the interference of the magnetic field from the magnetic shields 82a and 82b is received becomes consistent in the coils 80 arranged in the musical scale direction. Therefore, the increase or decrease in inductance caused by key pressing or key release in the coils 80 arranged in the musical scale direction can be suppressed.

[0062] In addition, for example, as in the fifth embodiment described later (see Figure 5 (a)) It is also possible to arrange a through hole such as the through hole 510 in the formation area of ​​the magnetic shield 82a and the magnetic shield 82b, but in the case of such a structure, the detection accuracy of the key information may be reduced. It is believed that the reason is that the magnetic field generated by the coil 80 (or the magnetic field generated by the magnetic shield 82a and the magnetic shield 82b due to the induced current) is distorted by the through hole 510.

[0063] Therefore, in the present embodiment, a structure is adopted in which the through hole 510 is not formed in the formation area of ​​the magnetic shield 82a and the magnetic shield 82b. In addition, not only the through hole 510 but also other holes (not shown) constituting the substrate 8 are formed at positions that do not overlap with the magnetic shield 82a and the magnetic shield 82b. As other holes constituting the substrate 8, flat holes (through holes without plating on the wall surface), through holes (through holes or holes connecting layers), through-holes (holes (recesses) for exposing the connection pads provided on the inner layer of the substrate 8), component holes (holes for mounting components), reference holes (through holes for positioning the substrate 8), etc. can be exemplified.

[0064] By not forming a hole (through hole or recess) that divides the magnetic shield 82a, 82b or cuts off a part of the magnetic shield 82a, 82b in the substrate 8, the magnetic field distortion of the coils 80a to 80d as described above can be suppressed. Therefore, the key information can be detected with good accuracy.

[0065] Then, refer to Figure 4 The second to fourth embodiments are described. Note that the same reference numerals are given to the same parts as those in the first embodiment, and description thereof will be omitted. Figure 4(a) is a partially enlarged cross-sectional view of the substrate 208 of the second embodiment, Figure 4 (b) is a partially enlarged cross-sectional view of the substrate 308 of the third embodiment. Figure 4 (c) is a partially enlarged cross-sectional view of the substrate 408 of the fourth embodiment. The magnetic shields 82a and 82b of the second to fourth embodiments have the same structure as the magnetic shields 82a and 82b of the first embodiment except for the difference in the stacked layers.

[0066] like Figure 4 As shown in (a), the first coil 80 ( Figure 4 The left coil 80 of (a) is surrounded by magnetic shields 82a and 82b stacked on the outer layers of the laminated plates 81a and 81c. Figure 4 The right coil 80 of (a) is surrounded by magnetic shields 82a and 82b as inner layers stacked between the laminated plates 81a to 81c. The first coil 80 and the second coil 80 are arranged alternately in the scale direction.

[0067] That is, in the substrate 208 of this embodiment, the magnetic shields 82a and 82b adjacent in the scale direction are stacked on different layers. Such magnetic shields 82a and 82b prevent the magnetic fields of the coils 80 adjacent in the scale direction from interfering with each other.

[0068] like Figure 4 (b) shows the first coil 80 ( Figure 4 (b) The left coil 80) is surrounded by the magnetic shield 82a which is the inner layer stacked between the laminated plates 81a and 81b and the magnetic shield 82b which is the outer layer stacked on the laminated plates 81c. On the other hand, the second coil 80 ( Figure 4 The coil 80 on the right side of (b) is surrounded by a magnetic shield 82a stacked on the outer layer of the laminated plate 81a and a magnetic shield 82b stacked on the inner layer between the laminated plates 81b and 81c. Moreover, these first coils 80 and second coils 80 are arranged alternately in the scale direction.

[0069] That is, in the substrate 308 of this embodiment, the magnetic shields 82a and 82b adjacent in the scale direction are also stacked on different layers. Such magnetic shields 82a and 82b prevent the magnetic fields of the coils 80 adjacent in the scale direction from interfering with each other.

[0070] In addition, the stacking methods of the second embodiment and the third embodiment may be combined (combining Figure 4The stacking method of the magnetic shield 82a and the magnetic shield 82b shown in (a) is the same as Figure 4 (b) shows a structure in which the magnetic shields 82a and 82b are stacked in a manner that is repeated alternately in the scale direction.

[0071] like Figure 4 As shown in (c), the substrate 408 of the fourth embodiment is a multilayer substrate having four laminated plates 481a to 481d stacked. Each of these laminated plates 481a to 481d is a copper-clad laminated plate having its upper surface (single side) covered with copper foil, and coils 80a to 80d are formed on the upper surface of each laminated plate 481a to 481d by a conductor pattern.

[0072] On the upper surface of the laminated plate 481a, magnetic shields 82a are arranged in the scale direction, and in the inner layer between the laminated plates 481c and 481d, magnetic shields 82b are arranged in the scale direction. That is, the magnetic shields 82a or 82b arranged in the scale direction are stacked on the same layer. As a result, the way in which the interference of the magnetic field from the magnetic shields 82a and 82b is received becomes the same in each coil 80 arranged in the scale direction.

[0073] Then, refer to Figure 5 and Figure 6 The fifth to eighth embodiments will be described below. However, in the fifth to eighth embodiments described below, the same components as those in the first to fourth embodiments are denoted by the same reference numerals and description thereof will be omitted. Figure 5 (a) is a top view of a substrate 508 according to the fifth embodiment. Figure 5 (b) is a top view of the substrate 608 of the sixth embodiment. Figure 6 (a) is a top view of a substrate 708 according to the seventh embodiment. Figure 6 (b) is a top view of the substrate 808 of the eighth embodiment.

[0074] like Figure 5 As shown in (a), the substrate 508 of the fifth embodiment is a substrate obtained by forming a through hole 510 in the substrate 8 of the first embodiment. The through hole 510 is a through hole that passes through the front and back of the substrate 508, and the inner wall of the through hole 510 is plated.

[0075] A plurality of through holes 510 are formed at the four corners and each side (long side and short side) of the four-sided annular magnetic shield 82a (not shown magnetic shield 82b). In addition, in the present embodiment, all of the plurality of through holes 510 are arranged to divide the magnetic shield 82a (the magnetic shield 82a becomes intermittent), but the present invention is not limited thereto. For example, a part (or all) of these through holes 510 may also be arranged to cut off a part of the magnetic shield 82a.

[0076] Even when such through holes 510 are provided, magnetic interference between adjacent coils 80 can be suppressed by the magnetic shield 82 a (magnetic shield 82 b not shown).

[0077] like Figure 5 As shown in (b), the substrate 608 of the sixth embodiment is a substrate that forms a magnetic shield 682 that divides the coil 80 by directly grounding (connecting to the ground). In addition, although not shown in the figure, the magnetic shield 682 is stacked on the outer layer of the front and back of the substrate 608, similar to the magnetic shield 82a and the magnetic shield 82b of the first embodiment.

[0078] The magnetic shield 682 has a plurality of blank portions (blanks) for providing linear gaps 683 between the coils 80 arranged in the scale direction, and the substrate 608 has a plurality of through holes 510 surrounding the gaps 683. The magnetic shield 682 can also suppress interference of magnetic fields between adjacent coils 80.

[0079] In addition, the magnetic shield 682 is formed continuously in the scale direction except for the blank part forming the gap 683 between the coil 80 and the area where the through hole 510 is formed. That is, each coil 80 is divided by the magnetic shield 682 formed by a single conductive pattern, but for example, the magnetic shield 682 can also be divided into a plurality of parts in the scale direction. In addition, the magnetic shield 682 can be configured not to be connected to the ground, and the through hole 510 can be omitted.

[0080] like Figure 6 As shown in (a), the substrate 708 of the seventh embodiment is obtained by replacing the substrate 608 of the sixth embodiment (see Figure 5 (b) A substrate in which the plurality of through holes 510 arranged along the long sides of the coil 80 among the through holes 510 are replaced with long through holes 710 .

[0081] The through holes 710 are formed into a pair with each coil 80 arranged in the scale direction, and each of the through holes 710 extends in a direction orthogonal to the scale direction. In addition, two through holes 710 are formed between each coil 80 arranged in the scale direction, but one or more than three through holes 710 may be formed between each coil 80. In addition, the two (or more) through holes 710 formed between each coil 80 may be connected in the scale direction.

[0082] In addition, for example, when the through hole 710 is set as a hole such as a through hole or a via hole (a hole that does not penetrate the substrate 708), the hole can also be formed into a continuous ring shape (a quadrilateral ring shape) to surround the coil 80.

[0083] like Figure 6As shown in (b), the substrate 808 of the eighth embodiment is formed with only the through hole 510 of the sixth embodiment (see Figure 5 (b)) has a through hole 510 along the long side of the coil 80 (through holes 510 other than these are omitted), and a substrate having a plurality of rectangular holes 684 formed in the magnetic shield 682. The plurality of holes 684 are distributed substantially uniformly throughout the formation area of ​​the magnetic shield 682. That is, the magnetic shield 682 is a direct ground provided with so-called cross hatching.

[0084] By providing cross hatching in the magnetic shield 682, the magnetic shield 682 is different from the sixth embodiment (see Figure 5 (b)) The porosity of the magnetic shield 682 is higher than that of the magnetic shield 682. This can prevent the magnetic field of the magnetic shield 682 from interfering with the magnetic field of each coil 80.

[0085] Although the above description has been given based on the above embodiment, it can be easily inferred that the present invention is not limited to the above embodiment at all, and various improvements and modifications can be made within the scope not departing from the gist of the present invention.

[0086] Part or all of the above-described embodiments may be combined with part or all of other embodiments, or may be replaced. Thus, for example, the magnetic shield 682 (directly grounded) of the sixth to eighth embodiments may be formed on the outer peripheral side of the magnetic shield 82a, 82b of the first or fifth embodiment, or the magnetic shield 82a, 82b (magnetic shield separated by the through hole 510) of the fifth embodiment may be formed on the outer peripheral side of the magnetic shield 82a, 82b of the first embodiment.

[0087] In the above-described embodiments, a synthesizer is illustrated as an example of the keyboard device 1, but the present invention is not necessarily limited to this. For example, when the keyboard device 1 is an electronic organ, the structure can detect the displacement of the foot keyboard (operating member) caused by the player's operation based on the increase or decrease of the inductance of the coil 80. When the keyboard device 1 is an electronic piano, the structure can detect the displacement of the three pedals (operating members) caused by the player's operation based on the increase or decrease of the inductance of the coil 80. In any structure, the structures of the magnetic shield 82a, the magnetic shield 82b, and the magnetic shield 682 of the above-described embodiments can be applied.

[0088] In the above-described embodiments, the case where the displacement of the displacement member 7 linked to the key 2 (white key 2a) is detected based on the increase or decrease of the inductance of the coil 80 is described, but the present invention is not necessarily limited to this. For example, the following structure may be adopted: the displacement member 7 is omitted, and the displacement of the hammer (a hammer that links with the key 2 to give a tactile sensation when the key is pressed) or other displacement members such as the key 2 is detected based on the increase or decrease of the inductance of the coil 80. In addition, for example, the following structure may be adopted: the displacement of the displacement member 7 linked to the hammer, the foot keyboard of the electronic organ, or the three pedals of the electronic piano is detected based on the increase or decrease of the inductance of the coil 80. In these structures, the structures of the magnetic shield 82a, the magnetic shield 82b, and the magnetic shield 682 of the above-described embodiments may also be applied.

[0089] In the above-mentioned embodiments, the displacement member 7 is described as rotating around the shaft portion 92, but the displacement member 7 may be slidably displaced (rotation of an operating member such as the key 2 is converted into direct motion), and the sliding displacement of the displacement member 7 may be detected based on an increase or decrease in the inductance of the coil 80.

[0090] In the above-described embodiments, the description of the method of forming the detected portion 75 is omitted. However, examples of the method of forming the detected portion 75 include a method of attaching a metal plate to the outer surface of the displacement member 7 or a method of plating the surface of the displacement member 7.

[0091] In the above-described embodiments, the three-layer laminated boards 81a to 81c or the four-layer laminated boards 481a to 481d (the substrate is a multilayer printed wiring board) are stacked, but the substrate may be a single layer, two layers, or five or more layers.

[0092] In the above-mentioned embodiments, the structure in which the substrate 8 is directly supported on the bottom plate 3 is described. However, for example, when the bottom plate 3 is a conductor such as a steel plate, it is preferable to make the substrate 8 float relative to the bottom plate 3 (for example, the structure is such that the substrate 8 is supported on the chassis 4 made of synthetic resin, and the bottom plate 3 and the substrate 8 are not in contact). In this way, the influence of the conductive bottom plate 3 on the magnetic field of the coil 80 can be suppressed. In addition, similarly, when the chassis 4 is a conductor such as a steel plate, it is preferable to support the substrate 8 on the bottom plate 3 formed of a non-conductor such as synthetic resin or wood. In this way, the influence of the conductive chassis 4 on the magnetic field of the coil 80 can be suppressed.

[0093] In the first to fifth embodiments, the magnetic shields 82a and 82b are described as being formed in a quadrilateral ring shape, but the present invention is not necessarily limited to this. For example, the portion extending in the scale direction of the quadrilateral ring-shaped magnetic shields 82a and 82b may be omitted, and each coil 80 may be divided by a linear magnetic shield 82a and 82b extending in a direction orthogonal to the scale direction. In addition, a portion of the magnetic shield 82a and 82b may have a bent or curved portion, and the magnetic shield 82a and 82b may be formed in a circular ring shape or other polygonal shape. That is, as long as each coil 80 arranged in the scale direction can be divided, the shape of the magnetic shield 82a and 82b may be appropriately set, and may not necessarily correspond to the shape of the coil 80 (for example, a circular coil 80 may be surrounded by a quadrilateral ring-shaped magnetic shield 82a and 82b).

[0094] Furthermore, when the magnetic shields 82a and 82b are formed into an annular shape, it is preferable that the width of the magnetic shields 82a and 82b is substantially constant over the entire circumference thereof. The so-called substantially constant width means that the minimum and maximum values ​​of the width are within a range of ±30% relative to the average value of the width of the magnetic shields 82a and 82b over the entire circumference.

[0095] By making the width dimensions of the magnetic shields 82 a and 82 b constant over the entire circumference, the manner in which the interference of the magnetic field from the magnetic shields 82 a and 82 b is received becomes uniform over the entire circumference of the coil 80 .

[0096] However, the following structure may be adopted: the width dimension of the magnetic shield 82a, 82b varies in a part or all of the circumferential region of the magnetic shield 82a, 82b (for example, the width dimension of a part of the magnetic shield 82a, 82b is thinner or thicker than that of other parts).

[0097] In the first to fifth embodiments, the magnetic shields 82a and 82b arranged in the scale direction are described as being of the same shape (quadrilateral ring shape), but the present invention is not necessarily limited to this. For example, magnetic shields of different shapes such as quadrilateral ring-shaped magnetic shields or circular ring-shaped magnetic shields may be combined to divide each coil 80.

[0098] In the first to fifth embodiments, the magnetic shields 82a and 82b are stacked on the same layer as any of the coils 80a to 80d, but the present invention is not limited thereto. For example, the magnetic shields 82a and 82b may be stacked on a layer different from the coils 80a to 80d.

[0099] In the first to fifth embodiments, the magnetic shields 82a and 82b are not connected to the circuits constituting the substrate, such as the ground (a portion (layer) that becomes a reference potential when the electronic circuit of the substrate operates), and the adjacent magnetic shields 82a and 82b are not connected to each other, but the present invention is not necessarily limited to this. For example, the magnetic shields 82a and 82b may be connected to the ground, or a part or all of the magnetic shields 82a and 82b arranged in the scale direction may be connected by a conductor (copper foil).

[0100] In the first to fifth embodiments, the case where multiple layers (four or two layers) of coils 80a to 80d and magnetic shields 82a and 82b are stacked is described, but it is not necessarily limited to this. For example, the coil 80a, the coil 80d and either or both of the magnetic shields 82a and 82b may be single-layered. In addition, the number of layers of the coil and the magnetic shield may be the same, or the magnetic shield may be stacked with more layers than the coil.

[0101] In the fifth to eighth embodiments, the case where the through holes 510 and 710 are formed in the substrate is described. However, in addition to the through holes 510 and 710 (or in place of the through holes 510 and 710), other holes such as flat holes, through holes, through-holes, part holes, or reference holes may be formed at positions overlapping with the magnetic shields 82a, 82b, and 682. In addition, these other holes or the through holes 510 and 710 may be formed in the region between the coil 80 and the magnetic shields 82a, 82b, and 682. In addition, the method for manufacturing the holes in which the inner walls are plated can be a known method, so detailed description is omitted. As a known method, a method of drilling a hole in a laminated board using a cutting tool such as a drill and plating both surfaces of the laminated board including the inner peripheral surface of the hole to form copper foil can be exemplified.

[0102] Description of Figure Numbers

[0103] 1: Keyboard device

[0104] 7: Displacement Components

[0105] 8, 208, 308, 408, 508, 608, 708, 808: substrate

[0106] 80, 80a~80d: Coil

[0107] 81a~81c, 481a~481d: Laminated plates

[0108] 82a: Magnetic shield (first magnetic shield)

[0109] 82b: Magnetic shield (second magnetic shield)

[0110] 682: Magnetic shielding

[0111] 510, 710: through hole (hole)

Claims

1. A keyboard device, characterized in that: include: A plurality of displacement components are arranged in the scale direction and are displaced along with the operation of the performer; and a substrate having a coil for generating a magnetic field for detecting displacement of the plurality of displacement members, The substrate includes: a plurality of the coils, provided for each of the plurality of displacement members; and a magnetic shield that divides the plurality of coils from each other and is formed by the conductive pattern of the substrate.

2. The keyboard device according to claim 1, characterized in that: A plurality of annular magnetic shields surrounding the entire circumference of the coil are arranged in a scale direction.

3. The keyboard device according to claim 2, characterized in that: The plurality of magnetic shields are not connected to the circuit constituting the substrate.

4. The keyboard device according to claim 2, characterized in that: No hole is formed in the substrate at a position where the magnetic shield is formed.

5. The keyboard device according to claim 1, characterized in that: The substrate is a multi-layer substrate in which a plurality of laminated plates are stacked. The coil and the magnetic shield are stacked in multiple layers together with the stacked plates.

6. The keyboard device according to claim 5, characterized in that: The number of stacked layers of the magnetic shield is smaller than the number of stacked layers of the coil.

7. The keyboard device according to claim 1, characterized in that: The magnetic shield comprises: a first magnetic shield; and a second magnetic shield, which is stacked at a lower layer than the first magnetic shield. A plurality of the first magnetic shielding members arranged in the scale direction are stacked on the same layer, The plurality of second magnetic shields arranged in the scale direction are stacked on the same layer.

8. The keyboard device according to claim 1, characterized in that: The magnetic shield comprises: a first magnetic shield; and a second magnetic shield, which is stacked at a lower layer than the first magnetic shield. The first magnetic shielding members adjacent to each other in the scale direction are stacked in different layers, The second magnetic shields adjacent to each other in the scale direction are stacked in different layers.

9. A method for forming a magnetic shielding member, which is a method for forming a magnetic shielding member in a keyboard device, the keyboard device comprising: A plurality of displacement components are arranged in the scale direction and are displaced along with the operation of the performer; and a substrate having a coil for generating a magnetic field for detecting displacement of the plurality of displacement members, the substrate comprising: a plurality of the coils provided for each of the plurality of displacement members; and a magnetic shield for dividing the plurality of coils from each other, wherein the method for forming the magnetic shield is characterized in that: The magnetic shield is formed by the conductive pattern of the substrate.

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