JP2007003562A - Electronic keyboard instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic keyboard instrument capable of preventing influence from magnetic force of a speaker to a hammer in a simple structure, without separating the hammer and the speaker in distance and without using the magnetic proof type speaker. <P>SOLUTION: In an electronic piano in which, when a key 2 provided so as to be rotated on a keyboard chassis 1 is pressed, key touch feeling similar to an acoustic piano by applying action weight on the key 2 by the hammer 3 is obtained, a magnetic proof sheet 6 is provided on the key board chassis 1 at a position between the hammer 3 located near the speaker 5 and the speaker 5. Consequently, when musical tone is generated from the speaker 5 by pressing the key 2, even if the speaker generates magnetic field, a magnetic line of the magnetic field does not pass through the magnetic proof sheet 6. Thereby, even if the hammer 3 is made of iron metal material in consideration of environment, influence from the magnetic field generated in the speaker 5 to the hammer 3 located near the speaker 5 is prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic keyboard instrument such as an electronic piano or an electronic organ.

2. Description of the Related Art Conventionally, in an electronic piano, as described in Patent Document 1, a keyboard chassis, a key arranged on the keyboard chassis so as to be pivotable in the vertical direction, and a key that is rotated in accordance with a key pressing operation. A hammer that dynamically displaces and applies an action load to the key is provided, and when the key is pressed, the hammer applies an action load to the key so that a key touch feeling similar to an acoustic piano can be obtained. is there. In this type of electronic piano, the switch outputs an ON signal in response to a key pressing operation, and the speaker generates a musical sound based on the ON signal of the switch.
JP-A-11-305759

  However, in such a conventional electronic piano, in consideration of the environment, the hammer that applies an action load to the key is made of an iron-based metal material instead of lead. A magnetic field is generated in the loudspeaker, and the operation of the hammer is affected by the magnetic force of the magnetic field, so that the desired action load is not accurately applied to the key, and a key touch feeling similar to an acoustic piano is obtained. There is no problem.

  That is, in this electronic piano, when the hammer rotates and applies an action load to the key, the speaker generates a musical sound. Therefore, the hammer made of an iron-based metal material is caused by the magnetic force of the magnetic field generated in the speaker. It is sucked and the desired action load is not accurately applied to the key. In particular, when the pressed key is released, the hammer does not quickly return to the initial position, and the hammer's return action is hindered by the magnetic force of the speaker. Cause trouble.

  In order to avoid such problems, it has been studied to increase the distance between the hammer and the speaker or to use a magnetic shield type speaker. However, if the distance between the hammer and the speaker is increased, the instrument There arises a problem that the whole is enlarged, and when a magnetic-shield type speaker is used, there is a problem that the cost is increased.

  The problem to be solved by the present invention is that the electronic keyboard can prevent the influence of the magnetic force of the speaker on the hammer with a simple structure without separating the distance between the hammer and the speaker or using a magnetic shield type speaker. Is to provide a musical instrument.

In order to solve the above problems, the present invention includes the following components.
In addition, the reference numerals of the drawings attached to the respective components described in the section of the embodiment described later are attached to the respective components together with parentheses.

  As shown in FIGS. 1 and 2, the invention described in claim 1 includes a keyboard chassis (1), a plurality of keys (2) arranged on the keyboard chassis so as to be rotatable in the vertical direction, A plurality of hammers (3) made of an iron-based metal material that is rotationally displaced in accordance with a key pressing operation of a plurality of keys and applies an action load to each of the plurality of keys, and a key pressing operation of the plurality of keys. In response, a plurality of switches (rubber switches 4) for outputting ON signals, a speaker (5) for generating a musical sound based on the ON signals of the plurality of switches, the hammer located at least in the vicinity of the speakers, An electronic keyboard instrument comprising a magnetic shielding sheet (6) disposed between the speaker and the speaker.

  As shown in FIGS. 1 and 2, the invention according to claim 2 is a place where the magnetic shield sheet (6) is located between the speaker (5) and the hammer (3) located in the vicinity thereof. The electronic keyboard instrument according to claim 1, wherein the electronic keyboard instrument is provided on the keyboard chassis.

  According to the first aspect of the present invention, since the magnetic shielding sheet is disposed between at least the hammer located near the speaker and the speaker, the key is operated to press the key and the hammer is rotated to apply an action load to the key. When a magnetic field is generated in the speaker when the musical sound is generated from the speaker, the magnetic field lines of the magnetic field do not pass through the magnetic shielding sheet so that the magnetic force of the speaker does not affect the hammer near the speaker. Can be. For this reason, even if the hammer is made of an iron-based metal material instead of lead in consideration of the environment, the influence of the magnetic field generated by the speaker on the hammer located near the speaker can be prevented.

  For this reason, the hammer can be rotated and displaced well without being affected by the magnetic field generated by the speaker when the key is pressed, and the desired action load can be applied to the key, thereby approximating that of an acoustic piano. The key touch feeling can be obtained well, and it is easy to place a magnetic-shielding sheet between the speaker and the hammer without particularly separating the hammer and the speaker or using a magnetic-shield type speaker. With a simple structure, it is possible to reduce the overall size of the musical instrument and to reduce the cost.

  According to the second aspect of the present invention, since the magnetic-shielding sheet is provided in the keyboard chassis at a location located between the speaker and the hammer located in the vicinity thereof, a special space for providing the magnetic-shielding sheet or A special installation member is not required, and the magnetic-shielding sheet can be easily attached only to a necessary portion of the keyboard chassis. For this reason, even if a normal speaker is used, the overall size of the musical instrument can be prevented, and the speaker is not particularly limited by the installation location, so that the speaker can be freely installed at a desired location.

Hereinafter, an embodiment in which the present invention is applied to an electronic piano will be described with reference to FIGS. 1 and 2.
As shown in FIGS. 1 and 2, the electronic piano includes a synthetic resin keyboard chassis 1 and a plurality of synthetic resin keys 2 (white) provided on the keyboard chassis 1 so as to be rotatable in the vertical direction. A key and a black key (in this embodiment, a white key will be described)), a plurality of hammers 3 for applying an action load to each of the plurality of keys 2, and an ON signal in accordance with the key pressing operation of each key 2. Are output between the plurality of rubber switches 4, the speaker 5 that generates a musical tone based on the ON signal from the plurality of rubber switches 4, and the magnetic shield disposed between the speaker 5 and the hammer 3 located in the vicinity thereof. And a sheet 6.

  The keyboard chassis 1 also serves as a musical instrument case. As shown in FIGS. 1 and 2, a front cover portion 7 corresponding to the front end portion of the key 2 is provided at the front end portion (right end portion in the figure). It protrudes upward from the bottom. A key guide 9 is provided on the middle step 8 at the rear portion (left side in the figure) of the front cover portion 7 so as to protrude upward. Further, as shown in FIGS. 1 and 2, a front placement portion 10 is formed in the middle portion of the keyboard chassis 1, and the hammer 3 can be rotated on the front placement portion 10. A hammer support portion 11 for supporting is formed at substantially the same height as the middle step portion 8.

  Further, at the rear portion of the front mounting portion 10 in the keyboard chassis 1, as shown in FIGS. 1 and 2, the rear mounting portion 12 is substantially the same as the front cover portion 7 with the front rising portion 13 being supported. It is formed at a height. A switch board 14 is attached to the upper part of the front side of the rear mounting portion 12 along the arrangement direction of the keys 2 (in FIG. 1, the front and back surfaces of the paper surface). A rubber switch 4 is provided for each key 2. Further, a key support portion 15 is formed on the rear end upper portion of the rear placement portion 12. The key support portion 15 is provided with a key support shaft 16 for rotatably supporting the rear end portion of the key 2.

  As shown in FIGS. 1 and 2, the key 2 has key attachment holes 17 formed on both side surfaces of a rear end portion (left end portion in the figure), and the key attachment holes 17 serve as a key support for the keyboard chassis 1. It is rotatably attached to the key support shaft 16 of the section 15, and is thereby configured to rotate in the vertical direction about the key support shaft 16. A switch pressing portion 18 is formed on the rear side of the intermediate portion of the key 2 so as to correspond to the rubber switch 4 of the switch board 14 provided on the rear mounting portion 12 of the keyboard chassis 1. Further, on the front side of the intermediate portion of the key 2, a hammer connecting portion 19 that holds a hammer contact portion 23, which will be described later, formed at the tip portion (right end portion in FIG. 1) of the hammer 3 is provided on the keyboard chassis 1. It is formed to extend downward on the front mounting portion 10.

  By the way, as shown in FIGS. 1 and 2, the rubber switch 4 includes a rubber sheet disposed on the upper surface of the switch substrate 14, and a dome-like bulge portion is provided on the rubber sheet, and the switch pressing portion 18 of each key 2. A pair of movable contacts having different heights are provided in the dome-shaped bulge, and the pair of movable contacts can be brought into contact with and separated from the pair of fixed contacts provided on the switch substrate 14. Are configured to be opposed to each other. As a result, as shown in FIG. 2, when the dome-shaped bulging portion is pressed by the switch pressing portion 18 of the key 2 in accordance with the key pressing operation, the rubber switch 4 is elastically deformed. The pair of movable contacts are configured to output an ON signal corresponding to the strength of the key touch by sequentially contacting the pair of fixed contacts with a time difference.

  On the other hand, as shown in FIGS. 1 and 2, the hammer 3 includes a hammer body 20 made of an iron-based metal material, and a synthetic resin bearing portion 21 is provided at a front side of the intermediate portion of the hammer body 20. The bearing portion 21 is provided on a hammer support portion 11 formed on the front mounting portion 10 of the keyboard chassis 1 so as to be rotatable by a support shaft 22. That is, as shown in FIGS. 1 and 2, the hammer body 20 has a rear end portion (left end portion in FIG. 1) disposed below the rear placement portion 12 in the keyboard chassis 1 and a front end portion (FIG. 1). The right end portion of the keyboard chassis 1 protrudes upward from the front mounting portion 10 through an opening 13 a provided in the front rising portion 13 of the rear mounting portion 12, and the protruding bearing portion 21 extends to the hammer support portion 11. The support shaft 22 is rotatably attached.

  In this case, as shown in FIG. 1 and FIG. 2, the hammer body 20 is provided with a hammer contact portion 23 at the tip, that is, the end located on the front side (right side in FIG. 1) of the bearing portion 21, The hammer contact portion 23 is inserted and held in the hammer connecting portion 19 of the key 2, whereby the hammer body 20 is centered on the support shaft 22 supported by the hammer support portion 11 in conjunction with the key pressing operation of the key 2. By rotating in the vertical direction, an action load is applied to the key 2.

  The hammer body 20 is normally urged counterclockwise in FIG. 1 by its own weight, and the rear end portion (left end portion in FIG. 1) of the hammer body 20 is provided at the bottom portion of the keyboard chassis 1. The lower limit position of the hammer body 20 is regulated by abutting against a lower limit stopper portion 24 such as a felt disposed on the bottom plate 1a. Further, as shown in FIG. 2, the hammer main body 20 has a felt disposed on the lower surface of the rear end of the rear mounting portion 12 of the keyboard chassis 1 when it rotates clockwise against its own weight. The upper limit position of the hammer body 20 is regulated by contacting the upper limit stopper portion 25.

  By the way, at the rear of the rear end of the hammer body 20, as shown in FIG. 1 and FIG. 2, a click feeling that gives the key 2 a key touch feeling that approximates the key touch feeling that can be obtained with an acoustic piano. An imparting member 26 is provided. The click feeling imparting member 26 includes a synthetic resin roller support 27 fixed to the bottom of the rear end of the keyboard chassis 1. In the roller support 27, a leaf spring portion 28 is formed in a substantially L shape at a position corresponding to each key 2 and extends upward. A roller 30 is attached to an attachment frame 29 formed at the upper end portion of the leaf spring portion 28. It is configured to be rotatably mounted.

  As a result, the click feeling imparting member 26 is formed when the hammer body 20 of the hammer 3 rotates clockwise around the support shaft 21 of the hammer support portion 11 when the key is depressed, as shown in FIGS. 1 and 2. The tip of the protrusion 20 a provided at the rear end of the hammer body 20 abuts against the roller 30, and the tip of the protrusion 20 a of the hammer body 20 resists the spring force of the leaf spring portion 28 of the roller support 27. Thus, when the roller 30 is passed over, a key touch feeling that makes the key 2 come out is given.

  On the other hand, an upper case 31 is attached above the rear portion of the keyboard chassis 1 as shown in FIGS. The upper case 31 includes an upper surface portion 32 located above the rear portion of the rear side of the keyboard chassis 1 from above the rear portion of the key 2 and a rear surface portion 33 suspended from the rear end portion of the upper surface portion 32. Thus, the keys 2 are elongated along the arrangement direction of the keys 2 (the front and back directions of the paper in FIG. 1), and the lower portion of the rear surface portion 33 is attached to an attachment portion 34 provided at the bottom rear end of the keyboard chassis 1.

  As shown in FIGS. 1 and 2, speakers 5 that generate musical sounds are exposed upward at both ends in the longitudinal direction of the upper surface portion 32 of the upper case 31 (both ends in the front and back direction of the paper surface in FIG. 1). Each is attached in the state. The speaker 5 is configured to generate a musical sound based on ON signals of a plurality of rubber switches 4 provided on the switch board 14. Further, a magnetic shielding sheet 6 is provided on the rear surface of the keyboard chassis 1 at a position located between the rear end portion of the hammer 3 located in the vicinity of the speaker 5 and the speaker 5.

  The magnetic shield sheet 6 is configured to prevent the magnetic field generated by the speaker 5 from affecting the hammer body 20 made of an iron-based metal material. That is, in the magnetic shielding sheet 6, the magnetic field lines of the magnetic field generated by the speaker 5 enter only the surface of the magnetic shielding sheet 6, and eddy currents are generated only on the surface, and do not enter the magnetic shielding sheet 6. It is guided along the surface, and as a result, it has a function as a magnetic shielding effect by preventing the passage of magnetic lines of force, so that the influence of the magnetic force of the speaker 5 does not reach the hammer body 20.

Next, the operation of such an electronic piano will be described.
Normally, as shown in FIG. 1, the hammer 3 is urged counterclockwise around the support shaft 22 of the hammer support portion 11 by the weight of the hammer body 20, so that the rear end portion of the hammer body 20 is moved to the lower limit stopper. The hammer 3 is in contact with the portion 24 and is restricted to the lower limit position. At this time, since the hammer contact portion 23 at the tip of the hammer body 20 is inserted and held in the hammer connection portion 19 of the key 2, the hammer connection portion of the key 2 is connected by the hammer contact portion 23 of the hammer body 20. The part 19 is pushed up, whereby the key 2 is restricted to the upper limit position.

  In this state, when the key 2 is pressed against the weight of the hammer body 20 of the hammer 3, the key 2 rotates clockwise in FIG. 1 about the key support shaft 16 at the rear end. At this time, since the key 2 is guided by the key guide 8, it does not swing sideways and smoothly rotates to move the hammer connecting portion 19 of the key 2 downward and is inserted into the hammer connecting portion 19. The hammer contact portion 23 of the hammer body 20 is pushed down.

  Along with this, the hammer body 20 rotates clockwise around the support shaft 21 of the hammer support portion 11, so that a load corresponding to the weight of the hammer body 20 is applied to the key 2 and the key load becomes heavy. Thereby, since the action load according to operation | movement of the hammer main body 20 is provided to the key 2, the key touch feeling approximated to an acoustic piano is obtained. When the key 2 is further pressed, the switch pressing portion 18 of the key 2 presses the rubber switch 4 of the switch board 14 and elastically deforms the bulging portion of the rubber switch 4, so that the rubber switch 4 is strong in key touch. An ON signal corresponding to the sound is output, and the speaker 5 generates a musical sound.

  In this state, when the key 2 is further pressed and the hammer body 20 of the hammer 3 further rotates clockwise, the protrusion 20a at the rear end of the hammer body 20 comes into contact with the roller 30 of the click feeling imparting member 26. Although the key load becomes heavier, if the protrusion 20a at the rear end of the hammer body 20 climbs over the roller 30 against the spring force of the leaf spring portion 28 of the click feeling imparting member 26, the key load is suddenly lightened. Thus, a key touch feeling that approximates the key touch feeling that can be obtained with the acoustic piano on the key 2 is obtained. When the key is released, the hammer 3 rotates counterclockwise in FIG. 2 due to its own weight and returns to the initial position, and the key 2 also returns to the initial position.

  Thus, according to this electronic piano, when the key 2 is depressed, the hammer body 20 of the hammer 3 rotates to apply an action load to the key 2 and the rubber switch 4 presses the switch of the key 2. It is pressed by the unit 18 to output an ON signal, and thereby the speaker 5 generates a musical sound. At this time, the speaker 5 generates a magnetic field. Since the magnetic-shielding sheet 6 is provided on the keyboard chassis 1 located between the hammer 3 and the speaker 5 located in the vicinity of the speaker 5, the speaker 5. It is possible to prevent the influence of the magnetic force generated by the magnetic field generated on the hammer 3 by the magnetic shield sheet 6.

  That is, in consideration of the environment, even if the hammer body 20 of the hammer 3 is made of an iron-based metal material instead of lead, the magnetic field lines of the magnetic field generated by the speaker 5 do not pass through the magnetic shielding sheet 6. It is possible to prevent the magnetic force of the magnetic field generated in the above from affecting the hammer main body 20 located in the vicinity of the speaker 5, and thus the magnetic shield 6 prevents the magnetic force of the speaker 5 from affecting the hammer main body 20. it can. For this reason, the hammer body 20 of the hammer 3 can be suitably rotated and displaced in accordance with the key pressing operation of the key 2, and a desired action load can be applied to the key 2, so that a key touch feeling similar to an acoustic piano can be obtained. Can be obtained satisfactorily.

  In this case, in particular, the hammer body 20 of the hammer 3 is not affected by the magnetic force of the speaker 5, so that the click feeling imparting member 26 approximates the key touch feeling that can be obtained by the acoustic piano to the key 2. A delicate key touch feeling can be surely given. Further, when the key that has been pressed returns to the initial position, the returning operation of the hammer body 20 of the hammer 3 is not hindered by the magnetic force of the speaker 5, so that the hammer body 20 of the hammer 3 can be quickly moved to the initial position. In this way, there is no hindrance in the case of a continuous shot in which the same key is continuously pressed, and a good continuous shot can be achieved.

  Moreover, in this electronic piano, since the magnetic-shielding sheet 6 is provided in the keyboard chassis 1 of the location located between the speaker 5 and the hammer 3 located in the vicinity thereof, a special space for providing the magnetic-shielding sheet 6 or The magnetic shield sheet 6 can be easily attached only to a necessary portion of the keyboard chassis 1 without requiring a special installation member or the like. For this reason, the distance between the hammer 3 and the speaker 5 is not increased, or a magnetic-shield type speaker is not used, and the entire instrument can be reduced in size with a simple structure, and the normal speaker 5 is used. In addition, the cost can be reduced and the speaker 5 is not particularly limited by the installation location, so that the speaker 5 can be freely installed at a desired location.

  In the above-described embodiment, the case where the magnetic shield sheet 6 is provided only in a necessary portion of the keyboard chassis 1 located between the speaker 5 and the hammer 3 located in the vicinity thereof is described. The magnetic shield sheet 6 may be provided on the entire keyboard chassis 1 located between the hammer 5 and the hammer 3.

It is sectional drawing at the time of the non-key pressing of the electronic piano to which this invention is applied. It is sectional drawing at the time of key pressing of the electronic piano in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Keyboard chassis 2 Key 3 Hammer 4 Rubber switch 5 Speaker 6 Magnetic-shield sheet 11 Hammer support part 15 Key support part 20 Hammer main body

Claims (2)

Keyboard chassis,
A plurality of keys arranged on the keyboard chassis so as to be rotatable in the vertical direction,
A plurality of hammers made of an iron-based metal material that is rotationally displaced in accordance with a key pressing operation of the plurality of keys and applies an action load to each of the plurality of keys,
A plurality of switches each outputting an on signal in response to a key pressing operation of the plurality of keys;
A speaker for generating a musical sound based on the ON signals of the plurality of switches;
An electronic keyboard instrument comprising: at least the hammer located in the vicinity of the speaker; and a magnetic shielding sheet disposed between the speaker. The electronic keyboard instrument according to claim 1, wherein the magnetic shield sheet is provided on the keyboard chassis at a location located between the speaker and the hammer located in the vicinity thereof.

Images