JPH0438395Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] This invention is a pedal for an electronic musical instrument that has a simple structure, allows smooth operation of the foot keys, improves operability, and prevents the generation of noise. Regarding the keyboard.

[Prior art]

Conventionally, in electronic musical instruments such as electronic organs, which control the opening and closing of key switches by pressing keys on a manual keyboard to electrically generate musical tones of a predetermined pitch, musical tones are output from tone forming circuits, etc. It is also controlled by a pedal keyboard to generate musical sounds with rich playability. The pedal keyboard is usually placed on the bottom of the instrument body so that it can move up and down, but in this case, the structure must be simple and easy to install, the operation must be smooth, crisp, and easy to operate, and there must be no noise. Since it is required to minimize the occurrence of , the structure of the rotation fulcrum is particularly important when designing, and various proposals have been made in the past.
As an example, the conventional structure of the most common rotation fulcrum part (for example, Utility Model Publication No. 47-10213) is shown in Fig. 1. 1 is a frame forming the bottom of the instrument body, 2
3 is a foot key arranged along the bottom surface of frame 1;
is a bolt as a support shaft that supports the foot key 2 so as to be able to freely rotate in the vertical direction. 1 with a nut 6. Reference numerals 7 and 8 denote a pair of elastic members made of rubber or the like, and these elastic members 7 and 8 are fitted into the spacer 5 and disposed on the upper and lower surfaces of the foot key 2, respectively. When the foot key 2 is depressed, the foot key 2 is rotated as shown by the chain line by the compression of the elastic members 7 and 8, and the effect of musical sound output is controlled in accordance with this rotation angle.

However, in the structure of the rotation fulcrum in such a conventional pedal keyboard, although noise can be prevented from occurring by the pair of upper and lower elastic members 7 and 8, when the foot key 2 is depressed, the upper elastic member 7 (on the right side in the figure) and the front half of the lower elastic member 8 are compressed, so the reaction force acts to prevent the foot key from rotating, resulting in smooth and crisp movement. The drawback was that there was no.

Other structures of the rotation fulcrum include
As seen in No. 11584, it is also known that an engagement piece provided on the frame is engaged with an engagement recess provided on the foot key, and this engagement part is used as a pivot point. However, since the foot key cannot be completely prevented from moving away from the engagement piece, the foot key cannot be held securely, and as a result, rattling and noise are likely to occur. Further, there are drawbacks such as restrictions on how to attach the spring that gives the foot key a return habit.

[Summary of the idea]

This idea was made in view of the above-mentioned points, and includes an insertion hole formed in the foot key, a support shaft that is inserted into the insertion hole via a spacer and fixed to the frame, and a support shaft that is fixed to the frame. , a pair of upper and lower elastic members respectively disposed at the opening of the insertion hole on the lower surface constitute a rotation fulcrum of the foot key, and the key tip side of the lower elastic member and the tip of the lower opening of the insertion hole. This is a pedal keyboard for an electronic musical instrument that has an extremely simple structure of creating a space between the two sides, which prevents interference between the foot keys and the elastic member below when stepping on them, and allows the foot keys to operate smoothly. This is what we provide.

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

〔Example〕

FIG. 2 is a sectional view showing an embodiment of the pedal keyboard according to the invention, FIG. 3 is an enlarged sectional view of the main part when not in operation, and FIG. 4 is an enlarged sectional view of the main part when the pedal keyboard is depressed. In these figures, 10 is a front plate of the main body of the musical instrument, 11 is a bottom plate, and the lower end of the front plate 10 and the front end of the bottom plate 11 are connected by a frame 1.
The foot key 2 is integrally formed of metal, plastic, etc., and has a substantially U-shaped cross-section with a hollowed out bottom, and its rear end is rotated by a support shaft 3 on the bottom surface of the frame 1. It is held movably and is given a clockwise return habit by a spring 12.

The spring 12 is made of a compression coil spring, and a spring storage recess 13 is provided at the rear end of the upper surface of the foot key 2 behind the insertion hole 4 through which the support shaft 3 is passed.
The lower end portion is housed in the frame 1, and the upper end is pressed against the lower surface of the frame 1. The spring storage recess 13 is formed in a tapered shape, and the diameter of the bottom is set to be approximately equal to the outer diameter of the spring 12, thereby preventing the lower end of the spring 12 from moving in the front-rear and left-right directions during a depressing operation. are doing. On the other hand, the spring 12
Movement of the upper end is regulated and prevented by a movement prevention protrusion 14 protruding from the lower surface of the frame 1.
As shown in FIG. 5, this movement prevention protrusion 14 includes an arcuate protrusion 14a having a trapezoidal cross-sectional shape and an inner diameter approximately equal to the outer diameter of the spring 12;
a and a semi-truncated conical protrusion 14b located on the inside of the protrusion 14b.

The spring storage recess 1 is located at the rear end of the upper surface of the foot key 2.
An actuator 15 is integrally protruded from behind the actuator 15, and a through hole 16 is formed in the frame 1 corresponding to the actuator 15, and a switch 17 is provided. The switch 17 is operated by the actuator 15 when the foot key 2 is depressed, and the circuit is configured such that the volume of the musical tone output is controlled by a signal from the switch 17.

A protrusion 19 is integrally provided on the rear end surface of the foot key 2, and a hook-shaped lower limit stopper 20 is integrally provided on the lower surface of the frame 1 in correspondence with the protrusion 19. The protrusion 19 is normally pressed against the lower limit stopper 20 from above by the force of the spring 12, thereby restricting clockwise rotation of the foot key 2 and holding the foot key 2 substantially horizontally. ing. A cushioning member 21 such as felt is fixed to the lower surface of the frame 1 in correspondence with the protrusion 19, and the foot key 2
constitutes an upper limit stopper.

Now, the rotation fulcrum part 25 of the foot key 2 that characterizes this invention is arranged on the support shaft 3 which is inserted into the insertion hole 4 from below through the spacer 5, and on the upper and lower surfaces of the foot key 2. A pair of upper and lower elastic members 7 and 8 are provided. The support shaft 3 is composed of a bolt, the tip of which protrudes toward the surface of the frame 1, and is fixed with a nut 6. A cylindrical portion 26 is integrally formed on the lower surface of the foot key 2, and the center hole of this cylindrical portion 26 constitutes the insertion hole 4. The insertion hole 4 is formed into a tapered hole in which the hole diameter on the upper end opening side is larger than the hole diameter on the lower end opening side. The lower end opening (surface) of the insertion hole 4, that is, the tip side of the foot key 2 from the center of the lower end surface 26a of the cylindrical portion 26 is cut off diagonally at an appropriate angle as shown in FIG. A slope 27 is formed. Further, as shown in FIGS. 3 and 6, a protruding strip 28 extending in a direction perpendicular to the longitudinal direction of the foot key 2 is provided at the center of the lower end surface 26a in the front-rear direction to sandwich the insertion hole 4 therebetween. There is. This protrusion 28 has a substantially semicircular cross-sectional shape. Note that this protrusion 28 reduces the surface area of the fulcrum, prevents the elastic body 27 and the fulcrum from getting caught, and improves the operating feel of the pedal keyboard; otherwise, when operating the pedal keyboard, It feels sticky and sticky, which is not desirable.

As shown in FIG. 7, the upper elastic member 7 has a rectangular cross-sectional shape and a substantially C-shape, and is connected to the frame 1 so as to surround the outer peripheral surface of the front end side of the foot key 2 at the upper end of the spacer 5. It is interposed between the key 2. The lower surfaces of both ends of the elastic member 7 are cut off diagonally to form slopes 7a and 7b. Note that the elastic member 7 is integrally formed with the frame 1 by outsert molding.

On the other hand, the lower elastic member 8 constitutes a ring having a rectangular cross-sectional shape, is fitted into the spacer 5, and is interposed between the lower end surface 26a of the cylindrical portion 26 and the flange portion 5a of the spacer 5. Therefore, a wedge-shaped gap 30 is formed between the slope 27 of the lower end surface 26a and the front half of the upper surface of the elastic member 8, thereby providing elasticity between the foot key 2 and the lower side when the foot key 2 is depressed. Interference with member 8 is prevented.

That is, as shown in FIG. 4, when the front end of the foot key 2 rotates downward and tilts at the maximum angle due to the depressing operation, the slope 27 becomes almost horizontal and the first half of the upper surface of the lower elastic member 8 There is almost no interference by just being in close opposition to or in slight contact with.
Therefore, the elastic member 8 is not compressed and does not have any adverse effect on the rotation of the foot key 2.

Further, the upper elastic member 7 is formed into a substantially C-shape, and the lower surfaces of both ends form slopes 7a and 7b, thereby preventing interference with the foot key 2. It does not have any negative effect on the rotation.

As a result, the foot key 2 is not subjected to the reaction force due to the compression of the elastic members 7 and 8, and moreover, when it starts to tilt, it comes into approximately linear contact with the elastic members 7 and 8, so that it can be operated crisply and smoothly.

In addition, although the above-mentioned Example explained the case where the foot key 2 was arrange|positioned along the lower surface of the frame 1, this invention is not limited to this, and may be arrange|positioned along the upper surface.

Further, in the above embodiment, the lower end surface 26a of the cylindrical portion 26 is
Although the first half of the upper surface of the elastic member 8 is formed as a slope 27 to form a gap 30 between the elastic member 8 and the lower elastic member 8, it goes without saying that the front half of the upper surface of the elastic member 8 may be formed as a slope.

[Effect of idea]

As explained above, the pedal keyboard of the electronic musical instrument according to the present invention has elastic members disposed at the upper and lower openings of the tapered insertion hole formed in the foot key, and the rear end of the key of the upper elastic member. a gap is provided between the upper end opening of the insertion hole and the rear end of the key, a gap is provided between the front end of the key of the lower elastic member and the front end of the lower end of the insertion hole, and Since the foot key is configured not to compress the upper and lower elastic members when the key is depressed, the elastic members do not restrict the foot key, ensuring smooth operation of the foot key, and improving operability. In addition, the structure is simple, and the above effects can be easily obtained by simply replacing some parts of a conventional pedal keyboard, so existing products can be easily improved, and its practical effects are extremely large. be.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of the rotation fulcrum of a conventional pedal keyboard, Fig. 2 is a sectional view showing an embodiment of this invention, Fig. 3 is an enlarged sectional view of the main part when not in operation, Figure 4 is an enlarged cross-sectional view of the main parts during pedal operation,
FIG. 5 is a perspective view of the movement prevention protrusion, FIG. 6 is a bottom view of the cylindrical portion, and FIG. 7 is a perspective view of the upper elastic member. 1... Frame, 2... Foot key, 3... Support shaft,
4...Insertion hole, 5...Spacer, 6...Nut,
7... Upper elastic member, 8... Lower elastic member,
25...Rotation fulcrum portion, 27...Slope, 28...Protrusion body, 30...Gap.

Claims (1)

[Scope of utility model registration request] A foot lock is provided on a frame so as to be freely rotatable in the vertical direction, and a spring is provided for imparting a return habit to the foot key, and a rotation fulcrum portion of the foot key is provided on the foot key. A tapered insertion hole, a pair of upper and lower elastic members disposed in each opening of the insertion hole, and a support shaft passing through the pair of elastic members and the insertion hole and disposed on the frame. configure,
A gap is provided between the key rear end side of the upper elastic member and the key rear end side of the upper end opening of the insertion hole, and the key front end side of the lower elastic member and the key front end side of the lower end opening of the insertion hole. An electronic musical instrument pedal keyboard characterized by having a space between the two.