JPH06214569A - Electronic musical instrument keyboard device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a keyboard device for an electronic musical instrument in which sound emitted from the back side of a speaker is prevented from leaking to the outside of the housing and has excellent acoustic characteristics. [Structure] The casing 1 has a structure that substantially seals sound, and the entire casing 1 serves as a speaker box.
The sound emitted from the back side of the speaker 41 does not interfere with the sound emitted from the front side of the speaker 41.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard device for electronic musical instruments such as electronic pianos and electric tones.

[0002]

2. Description of the Related Art Conventionally, in a keyboard device of an electronic musical instrument in which a speaker is mounted inside a housing including a keyboard chassis, slit-shaped long holes are formed in the keyboard chassis in correspondence with each key.
A protrusion protruding from the lower surface of the key is vertically slidably inserted into the elongated hole to guide the key so as not to roll laterally.

[0003]

In the above-mentioned conventional device, the sound emitted from the back side of the speaker leaks to the outside of the housing through the long hole of the keyboard chassis and is emitted from the front side of the speaker. There is a problem that the acoustic characteristics deteriorate due to the interference.

By sealing the portion of the housing near the back side of the speaker, it is possible to prevent sound emitted from the back side of the speaker from leaking to the outside of the housing. Since the capacity of is small, the acoustic characteristics deteriorate.

The present invention has been made in view of the above circumstances, and an object thereof is a keyboard of an electronic musical instrument having good acoustic characteristics by preventing sound emitted from the back side of the speaker from leaking to the outside of the housing. To provide a device.

[0006]

In order to achieve the above-mentioned object, a keyboard device for an electronic musical instrument according to the present invention has a structure in which a housing is substantially sealed to prevent sound from being formed into a speaker box. The sound emitted from the back side of the speaker does not interfere with the sound emitted from the front side of the speaker.

[0007]

The housing including the keyboard chassis has a structure that substantially seals sound, and the entire housing serves as a speaker box.
Sound emitted from the back side of the speaker does not interfere with sound emitted from the front side of the speaker. Therefore, the acoustic characteristics are good.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical cross-sectional view of a keyboard device for an electronic musical instrument according to the present embodiment. In FIG. 1, reference numeral 1 is a housing which substantially has a structure for hermetically sealing sound and which is a speaker box. It is composed of a case body 2 and a keyboard chassis 3.

The housing body 2 comprises an upper case 4 and a lower case 5. In the upper case 4, a front side (left side in FIG. 1) portion 6 is approximately one step lower than a rear (right side in FIG. 1) portion 6 from a substantially middle portion in the front-rear direction (left and right direction in FIG. 1). The lower case 5 has a thin box shape, and the upper end surface of the peripheral side wall is joined and fixed to the lower end surface of the peripheral side wall of the upper case 4.

An opening 9 is provided in the upper surface wall 8 of the front portion 6 of the upper case 4. This opening 9 is formed in the upper case 4
It is provided between a lower end portion of the front wall 10 of the rear portion 7 and a rear wall 12 that faces the front wall 11 of the front portion 6 with a predetermined gap. The entire opening 9 is closed by the keyboard chassis 3.

The keyboard chassis 3 is made of metal or synthetic resin and has a main body 14 and a sub body 15. The front and rear portions 16 and 17 of the main body 14 are horizontal, and the intermediate portion 18 is gradually inclined upward as it goes from the front portion 16 side to the rear portion 17 side. A key guide 19 is provided at the front end of the main body 14.
Are provided at intervals in the left-right direction. The key guide 19 has a comb-teeth shape protruding in the vertical direction so as to be orthogonal to the front portion 16 of the main body 14. The front portion 16 of the main body 14 is provided with a slit (not shown) communicating with the gap between the key guides 19. The rear portion 17 of the main body 14 is one step higher than the middle portion 18. The sub body 15 is the vertical wall 2
An upper side wall 21 is provided so as to project rearward at the upper end of 0, and a lower side wall 22 is provided so as to project upward at the lower end of the vertical wall 20 to form a crank shape in cross section.

The upper surface of the upper side wall 21 of the sub body 15 is fixed to the lower surface of the intermediate portion 18 of the main body 14 on the front portion 16 side so that the main body 14 and the sub body 15 are integrated. The rear end portion of the rear portion 17 of the main body 14 is fixed to the lower end portion of the front wall 10 of the rear portion 7 of the upper case 4 by a plurality of (for example, five) screws 23a. Each of these screws 23a is a screw hole 25 of a boss portion 24 having a circular cross section, which is integrally projectingly provided on the rear side surface of the front wall 10 of the rear portion 7 of the upper case 4 at predetermined intervals in the left-right direction.
It is screwed to.

The front end portion of the lower side wall 22 of the sub body 15 is fixed to the lower end portion of the rear surface wall 12 of the front side portion 6 of the upper case 4 by a plurality of (for example, five) screws 23b. These screws 23 b are provided on the rear wall 12 of the front part 6 of the upper case 4.
Is screwed into a screw hole 27 of a boss portion 26 having a circular cross section, which is integrally formed on the front side surface of the boss at predetermined intervals in the left-right direction.

On the keyboard chassis 3, a plurality of white keys 28 and black keys 29 are mounted side by side in the left-right direction. Each white key 28
Is attached to the upper surface of the rear portion 17 of the main body 14 of the keyboard chassis 3 via the common base end portion 30 on the rear end side thereof and via the common base end portion 31 on the rear end side thereof. Each common base end portion 30, 31 is attached to the upper surface of the rear portion 17 of the main body 14 by a plurality of screws 32. Each of these screws 32 is screwed into a screw hole 34 of a boss portion 33 having a circular cross section which is provided on the lower surface of the rear portion 17 of the main body 14.

Protrusions 35 protruding from predetermined positions on both side walls of the white key 28 are fitted between the key guides 19 so as to be vertically movable,
The key guide 19 prevents the white key 28 from rolling laterally. In addition, like the white key 28, the black key 29 is also prevented from rolling by the key guide 19.

Stoppers 36 and 37 are provided on the upper and lower surfaces of the front portion 16 of the main body 14 of the keyboard chassis 3. White key 2
When the 8 and black keys 29 are pressed, the lower end surfaces of both side walls abut the stoppers 36 on the upper surface, whereby the lower limit positions of the white keys 28 and the black keys 29 are regulated. Also, white key 28 and black key 29
Is urged upward by a spring (not shown), the lower end abutting portion 35a of the projection 35 of each key 28, 29 abuts the stopper 37 on the lower surface, so that the white key 28 and the black key 2
The upper limit position of 9 is not pressed.

A circuit board 38 is attached to the upper surface of the intermediate portion 18 of the main body 14 of the keyboard chassis 3. A key switch 39 is attached to the upper surface of the circuit board 38. The key switch 39 is a normally open switch and is provided corresponding to the white key 28 and the black key 29. And
When the white key 28 and the black key 29 are pressed, the elastic member 39a of the key switch 39 is pressed by the actuator 40 (the actuator of the black key 29 is not shown) 40 provided on the white key 28 and the black key 29 to close them. Sound is produced from the speaker 41.

The speaker 41 is mounted on the upper wall 42 of the rear portion 7 of the upper case 4 with the front side facing upward. Corresponding to the speaker 41, a hole 43 is formed in the upper surface wall 42 of the rear part 7 of the upper case 4. The sound emitted from the front side of the speaker 41 is output to the outside of the housing 1 through the hole 43.

In FIG. 1, reference numeral 44 denotes an eaves-shaped cover wall projecting from the upper end of the front wall 10 of the rear side portion 7 of the upper case 4. The cover wall 44 allows the white key 28 and the black key to be provided. The upper surfaces of the common proximal end portions 30 and 31 of 29 are covered.

Next, the operation of the keyboard device of the electronic musical instrument having the above structure will be described.

FIG. 1 shows a state in which no key is pressed.
The black key 29 is held at the upper limit position because the lower end abutting portion 35a of the protrusion 35 is in contact with the stopper 37 on the lower surface, and the key switch 39 is in the open state.

When the white key 28 or the black key 29 is pressed downward from this state, the projection 35 is guided by the key guide 19 and the intermediate body 12 of the front part 6 of the upper chassis 4 and the sub body 15 of the keyboard chassis 3. It goes into the inside of the concave portion 45 defined by and. The white key 28 or the black key 29 is held at the lower limit position by contacting the lower ends of both side walls with the stoppers 36 on the upper surface, and the actuator 40 causes the key switch 3 to operate.
9 is closed, and sound is output from the speaker 41. At this time, the sound emitted from the front side of the speaker 41 is emitted to the outside of the housing 1 through the hole 43 of the upper surface wall 42 of the rear side portion 7 of the upper case 4, but the sound emitted from the back side of the speaker 41 is changed to the housing. Since the body 1 has a structure that substantially seals sound, it does not go out of the housing 1.

When the white key 28 or the black key 29 is released from the pressing force, the white key 28 or the black key 29 is rotated upward by the biasing force of the spring, and the key switch 39 is turned on.
Opens and returns to the state shown in FIG.

[0025]

As described in detail above, according to the keyboard device for an electronic musical instrument of the present invention, the housing including the keyboard chassis has a structure that substantially seals sound, and the sound emitted from the back side of the speaker is the front side of the speaker. Since it does not interfere with the sound emitted from the housing and the entire casing serves as a speaker box, the acoustic characteristics are improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a keyboard device for an electronic musical instrument according to an embodiment of the present invention.

[Explanation of symbols]

 1 case 3 keyboard chassis 41 speaker

Claims (1)

[Claims] 1. A keyboard device for an electronic musical instrument, wherein a speaker is mounted inside a casing including a keyboard chassis, and the casing is formed as a speaker box so that the casing is substantially acoustically sealed. A keyboard device for an electronic musical instrument, wherein a sound emitted from a back side of the speaker does not interfere with a sound emitted from a front side of the speaker.