JPH0447751Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an after-control device for an electronic keyboard instrument that has a simplified structure and improved assembly workability.

Conventionally, in electronic keyboard instruments, so-called after-controls such as tremolo effects, vibrato effects, and tremolo speed control are added to the musical tones generated by key presses to obtain various slightly changing musical tones. This after-control device generally involves manually operating various control switches such as a tremolo switch placed on the operation panel surface to obtain a desired performance effect, or by using the key when the key is pressed to achieve a similar effect. I'm trying to get results. Among these, as an after-control device that uses a key, for example, a key press pressure detection device for an electronic musical instrument disclosed in Japanese Utility Model Application Publication No. 121726/1983 is known. As shown in FIG. 1, this consists of an electrode substrate 1 and an elastic conductor 2 that face each other vertically, and a pair of elastic insulators 3a and 3a interposed between them along both edges in the longitudinal direction.
3b, and a flexible electrode plate 4 that is conductively fixed to the elastic conductor 2, and when a key is pressed, the elastic conductor 2 is bent downward to increase the contact area with the electrode substrate 1. And the contact pressure is changed according to the pressing force, and the electrode substrate 1 and the flexible electrode plate 4 are changed accordingly.
This was designed to add after-control by changing the resistance value between the two, but there were problems with manufacturing, assembly, etc.

That is, since a pair of elastic insulators 3a and 3b are required, the number of parts increases, manufacturing and installation work are troublesome, and if the elastic insulators 3a and 3b are installed at different positions, even with the same pressing force, the elastic electrode Since the amount of deflection of the plate 2 is different, the resistance value changes and the quality tends to vary.

This idea was made in view of the above-mentioned points, and consists of a bottom surface extending in the key arrangement direction, both side surfaces of the bottom surface standing at both ends in the longitudinal direction of the keys, and extensions of both sides bent outward. a case having a cross-sectional shape uniformly approximately in the shape of a letter "H" in the direction in which the keys are arranged; and a conductive sheet and a pressure-sensitive conductive sheet laminated inside the case. It consists of a pressure-sensitive conductive part and a buffer member that covers the top surface of the case across both inclined receiving parts after the pressure-sensitive conductive part is housed in a case, and the key presses the buffer member when the key is pressed. By changing the resistance value of the pressure-sensitive conductive part according to the pressing force, manufacturing and assembly are easy;
An after-control device for electronic keyboard instruments that prevents injuries from burrs or the sensor sheet from getting stuck when attaching shock absorbers, is suitable for unmanned assembly such as by robots, and reduces manufacturing costs. This is what we provide.

This invention will be described in detail below based on embodiments shown in the drawings.

FIG. 2 is a perspective view of a main part of an embodiment of the after-control device according to the invention, and FIGS. 3 and 4 are an exploded perspective view and a vertical sectional view of the sensor in an assembled state. In FIG. 2, reference numeral 10 denotes a keyboard frame arranged almost horizontally on a shelf board (not shown) of the main body of the musical instrument, and a keyboard 11 consisting of a plurality of white keys 11a and black keys 11b is mounted on the top surface of the frame. The end portion is supported and is arranged to be freely rotatable in the vertical direction. A stopper 12 is integrally provided on the lower surface of the front end of each key 11a, 11b, and the lower end thereof is vertically movable into a through hole 14 bored in a vertical wall 13a that constitutes the stepped portion 13 of the keyboard frame 10. This restricts the vertical and horizontal rotation of the keys 11a and 11b. Further, each key 11a, 11b is always given a return habit in the counterclockwise direction in FIG. The front end portion is configured to rotate and lower when a key is pressed. Then, as the keys are pressed, each key 11a, 1
When the key 1b rotates and descends, the actuator 16 vertically disposed at the center of its lower surface also descends to operate the key switch 17 disposed on the back of the keyboard frame 10, thereby producing the musical tone corresponding to the key. It is electrically formed and produced. In this case, when each of the keys 11a, 11b is operated with a pressing force during normal performance, the lower surface of the stopper 12 comes into contact with the upper surface of a buffer member 21, which will be described later, to restrict downward rotation.

On the upper surface 13b of the stepped portion 13, a sensor 20 constituting an after-control device is disposed in common for the plurality of keys 11a and 11b.
As shown in FIGS. 3 and 4, this sensor 20 is integrally formed of plastic or the like.
It is housed in a case 22 that is integrally provided with side walls 22a and 22b on both sides in the longitudinal direction, and includes a pair of upper and lower conductive plates (conductive sheets) 23, 2.
4, a resistor (pressure-sensitive conductive sheet) 25 made of an elastic material such as pressure-sensitive conductive rubber, interposed between the pair of conductive plates 23 and 24, and a pair disposed on both sides of the resistor 25 in the longitudinal direction. The resistor 25 and the end spacers 26a, 26b form a resistor part, and the buffer member 21 is laminated on the upper surface of the upper conductive plate 24. There is. The widths W ₁ of the pair of conductive plates 23 and 24, the resistor 25 and the pair of end spacers 26A and 26B are all the same and are set approximately equal to the distance W between the inner surfaces of the side walls 22a and 22b of the case 22. This prevents displacement in the width direction when attached to the case 22. Terminal portions 28 and 29 projecting to the sides of the case 22 are integrally provided on one end surface of the pair of conductive plates 23 and 24, respectively, with their positions shifted back and forth. The lead wires are connected to each.
Further, the lower conductive plate 23 has approximately the same length as the case 23 and is fixed to the upper surface of the case 23,
The upper conductive plate 24 is 2a smaller than the lower conductive plate 23.
It is formed short. The pair of conductive plates 23 and 24 and the resistor 25 form a pressure-sensitive conductive section.

On the other hand, the resistor 25 is connected to the upper conductive plate 24.
A pair of end face spacers 26A and 26B are arranged on both sides of the lower conductive plate 23 with their outer end faces aligned with each side surface of the lower conductive plate 23,
This prevents the pair of conductive plates 23 and 24 from coming into contact with each other. Moreover, by stacking the upper conductive plate 24 together with the resistor 25 so that its center coincides with the center of the lower conductive plate 23, both ends are retracted from the lower conductive plate 23 by the dimension a, respectively.
The insulation from the conductive plate 23 is made perfect.

The case 22 includes a bottom surface 22A extending in the key arrangement direction, both side surfaces (side walls) 22a and 22b standing at both ends of the bottom surface 22A in the key longitudinal direction, and the both side walls 22A.
By being composed of inclined receiving parts (hereinafter simply referred to as receiving parts) 30a and 30b formed by bending the upper ends of a and 22b outward so that the tips thereof face obliquely downward, the cross-sectional shape is key. The receiving portions 30a,
Both ends of the short side of the buffer member 21 are adhesively fixed to the upper surface of the buffer member 30b. The sensor 20 configured in this way has the receiving portion 30a connected to the vertical wall 1.
3a and placed on the upper surface 13b of the stepped portion 13, the key is located below the stopper 12 of each key 11a, 11b, and detects the pressing force of the key pressed during after-control.

In other words, when a key is pressed with a pressure greater than that during normal performance, the stopper 1 of the key is pressed.
2 contacts and presses the buffer member 21, the pressed portion of the buffer member 21 is recessed in accordance with the pressing force, changing the contact pressure between the conductive plates 23, 24 and the resistor 25. As a result, the conductive plate 23,
A change occurs in the resistance value between the two terminals 24, and by taking out this change from the terminal sections 28 and 29 and applying it to the sound generation control circuit, after control is applied to the generated musical tone.

Thus, according to the after-control device configured as described above, the side walls 22a, 22
Since the sensor 20 is placed and fixed on the upper surface of the case 22 having ,24
Since the lengths are changed, there is no chance of accidental contact, which improves reliability. Further, a receiving portion 30 is provided on each side wall 22a, 22b of the case 20.
a and 30b are provided integrally, and one of them is connected to the stepped portion 13.
Since it is in contact with the vertical wall 13a of case 2,
0 is easy to position, and even if the lower end of the vertical wall 13a is formed into a curved surface as shown in FIG. 4, if the length l of the receiving part 30a is set sufficiently long, the case 20 will not tilt. or positioning becomes inaccurate. In addition, case 20 is
Since it is formed in an approximately "H" shape when viewed from the side, there is less chance of injury from burrs etc. when installing the buffer member 21 (if done by hand) than when the buffer member 21 is simply U-shaped. In addition, when assembling unattended, it is possible to prevent the sensor sheet from getting caught by burrs, etc. Moreover, the sensor (including electrodes) can be simply stacked and inserted from above, and finally covered with the buffer member 21. This structure makes it suitable for assembly by robots. Moreover, the buffer member 21 is
In addition to buffering function, it also has dustproof function. Further, the resistor 25 is formed into a plate shape and has a pair of conductive plates 23,
Since it is interposed over almost the entire length between the 24
Upper conductive plate 2 compared to the conventional structure shown in Figure 1.
4 can be held stably, and the distance between both conductive plates 23 and 24 can be kept constant.

As explained above, the after control device for an electronic keyboard instrument according to this invention comprises a sensor consisting of a pair of electrode plates and a resistor made of an elastic material interposed between these electrode plates, and the sensor and the buffer Because the components are stacked in a case with side walls, manufacturing and assembly are easy.
Productivity can be improved. In addition, since the electrode plate, resistor, etc. are positioned by the side wall of the case, manufacturing and assembly are easy, and there is no risk of injury from burrs or the sensor sheet getting stuck when attaching the buffer member, making it easier for robots to etc., it is suitable for unattended assembly, so it is possible to reduce manufacturing costs and perform high-precision assembly, making it possible to obtain sensors of uniform quality.Moreover, by changing the length of a pair of conductors, it is possible to Since both ends are retracted from the ends of the resistor, the conductors do not come into contact with each other unexpectedly, improving reliability, and this has great practical effects.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an example of a key press pressure detection device used in a conventional electronic musical instrument, Fig. 2 is a perspective view showing an embodiment of an after-control device according to this invention, and Fig. 3 is a sensor. Fig. 4 is a longitudinal sectional view of the sensor in its assembled state;
FIG. 5 is a diagram for explaining the effect of the receiving part of the case. 10... Keyboard frame, 11a... White key, 11
b...Black key, 12...Stopper, 20...Sensor, 21...Buffer member, 22...Case, 23,
24... Conductive plate, 25... Resistor.

Claims (1)

[Claims for Utility Model Registration] A bottom surface extending in the key arrangement direction, both side surfaces of the bottom surface standing at both ends in the longitudinal direction of the keys, and an inclined receiver formed by bending the extensions of the both side surfaces outward, respectively. a case having a cross-sectional shape uniformly in the shape of a letter "H" in the direction in which the keys are arranged; a pressure-sensitive conductive section made of a conductive sheet and a pressure-sensitive conductive sheet laminated inside the case; after the piezoconductive part is housed in the case, a buffer member covers the upper surface of the case across both inclined receiving parts, and when the key presses the buffer member when the key is pressed, the pressure-sensitive conductor An after-control device for an electronic keyboard instrument, characterized in that a resistance value of the portion changes in accordance with the pressing force.