JPH0233276Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a keyboard device for an electronic musical instrument that can control the volume of a sound by using a timing difference between two circuits.

A recent keyboard device for an electronic musical instrument has been constructed as shown in FIG.

That is, the engaging part 5 at one end of the key 4 is engaged with the engaging hole 3 of the bent part 2 at one end of the chassis 1 made of a metal plate, and the spring 6 is interposed between the chassis 1 and the key 4. Press the other end of the key 4 upward, and press the key 4.
An operating piece 7 is provided on the lower surface of the intermediate portion of the key 4, and an L-shaped stopper piece 8 is provided on the lower surface of the other end of the key 4, and this stopper piece 8 is made to protrude from the lower surface of the chassis 1 and is attached to the lower surface of the chassis 1. A key guide piece 11 is provided at the other end of the chassis 1 to restrict the upward movement of the key 4 by coming into contact with the cushioning material 9, and a board holder 12 is provided on the bottom surface of the chassis 1. , a printed circuit board 15 is attached using spacers 13 and screws 14, an inverted cup-shaped operating elastic body 16 is provided at the contact portion of this printed circuit board 15, and a movable contact is mounted within this operating elastic body 16. .

With this configuration, by moving the key 4 under pressure against the spring 6, the operating piece 7 of the key 4 presses and deforms the operating elastic body 16, and the movable contact contacts the contact portion of the printed circuit board 15. Let me touch you and switch
When the pressing force of the key 4 is released, the elastic force of the spring 6 causes the key 4 to be turned on.
returns to its upward movement, and the operating elastic body 16 returns to its normal inverted cup shape due to its own elasticity, turning the switch OFF.

In such a keyboard device for an electronic musical instrument, the conventional operating elastic body 16 has a conductive rubber contact 18 provided on the lower surface of a downwardly projecting portion 17 at the center of the interior, as shown in FIG. .

With this configuration, it is not possible to control the volume of sound using the timing difference between the two circuits.

As shown in Figure 3, two circuits that control the volume of sound using the timing difference between these two circuits are
There is a structure in which an actuator 20 is attached to a step-type movable contact piece 19 and is pressed and controlled by the operating piece 7 of the key 4, but this requires a large operating force and is complicated and costly. Even when a timing difference between the ON stroke of the 1st circuit and the 2nd circuit is required, it is difficult to achieve accuracy, and therefore, a great deal of effort is required for adjustment.

The purpose of the present invention is to eliminate the above-mentioned conventional drawbacks, and to provide a keyboard device for musical instruments that has a simple structure and can control the volume of sound by setting a timing difference in the reliable ON of two circuits. It is something to do.

In order to achieve the above object, the present invention provides two protrusions with different heights inside the inverted cup-shaped operating elastic body, and provides conductive rubber contacts on these two protrusions to connect the two protrusions on the printed circuit board. The structure is such that switching between the sets of contacts can be performed with a timing difference.

Hereinafter, an embodiment of the present invention will be explained with reference to FIG. 4 of the drawing.

The overall structure of the keyboard device for an electronic musical instrument is the same as that shown in FIG. 1, and the specific structure of the operating elastic body 16 as a switch section will be explained here.

This operating elastic body 16 has an inverted cup shape with a cap-shaped portion 16a made of rubber or the like, and a cylindrical portion 16b provided at the center upper surface of the cap-shaped portion 16a. A downward protruding portion 17a is provided, and a cylindrical portion 16b is provided on the outer periphery of the protruding portion 17a.
A protruding portion 17b having approximately the same diameter as that of the conductive rubber contact 18 is provided on the lower surface of the protruding portions 17a and 17b.
a, 18b are provided.

Note that the protrusion 17a is dimensioned to protrude more downward than the protrusion 17b.

With this configuration, by moving the key 4 under pressure against the spring 6, the operating piece 7 of the key 4 comes into contact with the cylindrical part 16b of the operating elastic body 16, deforming the cap-shaped part 16a, and first When the conductive rubber contacts 18a of the protrusion 17a are brought into contact between the contacts of the printed circuit board 15 and the key 4 is further moved down, the cap-shaped portion 16a is greatly bent, and the conductive rubber 18b of the protrusion 17b is connected to the other side of the printed circuit board 15. contact between the contacts.

When the operating force on the key 4 is released, the spring 6 causes the key 4 to return to its upward movement, and the operating elastic body 16 also returns to its original state due to its own elasticity.

As the keyboard device for an electronic musical instrument of the present invention is configured as described above, it is possible to perform ON/OFF control with a timing difference between two circuits with a simple configuration, and to perform performances that can control the volume of the sound. Timing differences can be adjusted by adjusting the height of the protruding part of the operating elastic body, and the operating force can be reduced, the fingers will not feel fatigued, and it has the advantage of being cost-effective, making it practical. It is of great value.

Further, the operating elastic body is provided with a first downward protrusion in the center of the cap-shaped part, and a second protrusion having approximately the same diameter as the cylindrical part on the key side of the cap-shaped part is provided on the outer periphery of the first protrusion. Since the structure is such that a contact point is provided on the lower surface of the first and second protrusions,
When operating this operation elastic body by pressing the key, the contact of the first protrusion in the center comes into contact with the contact of the printed circuit board, and then the cap-shaped part on the outer periphery is deformed and the second protrusion The contacts of the first and second protrusions contact the contact parts of the printed circuit board, that is, the contacts of the first and second protrusions contact the contact parts in order as the cap-shaped part descends from the center. This reduces the so-called two-stage pressing sensation caused by the different heights of the parts, resulting in a better operating feel.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view of a typical keyboard device for electronic musical instruments, Fig. 2 is a sectional view of the main parts of a conventional keyboard device for electronic musical instruments, and Fig. 3 is another conventional keyboard device for electronic musical instruments. FIG. 4 is a partially cutaway side view showing an embodiment of the keyboard device for an electronic musical instrument according to the present invention. DESCRIPTION OF SYMBOLS 1... Chassis, 2... Bending part, 3... Engaging hole, 4... Key, 5... Engaging part, 6... Spring, 7... Operation piece, 8... Stopper piece, 9... ...Buffer material, 10...Elastic material, 11...Key guide piece,
12...Substrate holder, 13...Spacer, 14...
... Screw, 15 ... Printed circuit board, 16 ... Operation elastic body, 16a ... Cap-shaped part, 16b ... Cylindrical part, 17a, 17b ... Projection part, 18a, 18b
...Conductive rubber contacts.

Claims (1)

[Scope of utility model registration request] An operating piece is provided on the underside of the key which is rotatably incorporated with one end pivotally attached to the chassis, and an operating piece made of an elastic body is provided below the operating piece and corresponds to the contact part of the printed circuit board attached to the chassis. Provide an elastic body,
This operating elastic body has a structure having a cap-shaped part and a cylindrical part provided on the key side of the cap-shaped part, and a first downward protrusion part is provided in the center of the cap-shaped part. A second protrusion having approximately the same diameter as the cylindrical part is provided on the outer periphery of the protrusion so that the amount of protrusion is smaller than the amount of downward protrusion of the first protrusion. 2. A keyboard device for an electronic musical instrument, in which contacts are provided on the lower surfaces of the two protruding parts, and these contacts correspond to the contact parts.