JPS638944Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a key drive device for a self-playing piano that drives keys by a solenoid.

Generally, a player piano is equipped with a key driving device that drives the keys using an electrical signal obtained by reproducing a prerecorded electrical signal. A solenoid is used as the key drive device, and is energized by the above-mentioned electric signal. The magnetic flux generated by the excitation of the solenoid drives in the axial direction an iron core, that is, a plunger, which is slidably disposed through the solenoid with a small gap, and the plunger pushes the key upward. It operates as if the keys were pressed by hand. In this case, the solenoid is normally installed on the underside of the shelf, with the plunger protruding above the shelf from a through hole drilled in the shelf, and its protruding end attached to the underside of the rear end of the key. They are kept close together.

However, in such a conventional mounting structure, it is necessary to drill the same number of through holes in the shelf board as the number of keys to allow the plunger of each solenoid to pass through, which may significantly reduce the strength of the shelf board or make it difficult to penetrate the shelf board. It becomes necessary to change the mounting position of the pedal ejection bar, etc., which is arranged as a pedestal. Further, since the piano body is tilted down when drilling the through holes, the work is large-scale and not only is it unsuitable for use in a general household, but also cutting waste remains inside the piano body and is difficult to remove. In addition, it is difficult to drill holes from the bottom surface of the shelf board with high precision for the key. Furthermore, in a grand piano type player piano, the keyboard reed is arranged on the shelf so that it can be taken out freely, so if the plunger protrudes above the shelf, it takes time to put in and take out the keyboard reed. There were many inconveniences, such as bending.

This idea was made in view of the above-mentioned points, and is extremely unique in that a solenoid is installed vertically on the rear end of the shelf, and the downward movement of the plunger is converted into upward movement by a rotary lever, which is then transmitted to the key. It is an object of the present invention to provide a key drive device for a player piano that has a simple configuration and solves the above-mentioned conventional problems at once.

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

FIG. 1 is a sectional side view of an action mechanism showing an embodiment of an upright automatic performance piano equipped with a key drive device according to the invention, and FIG. 2 is a plan view of the main part of the device. In these figures, a keyboard reed 2 is disposed on a shelf board 1, and on top of the keyboard reed 2, a plurality of keys 4 corresponding to strings 3 of each pitch are respectively movable in the vertical direction. supported and arranged in parallel. That is, the key 4 is supported at its middle by a balance key pin 6 implanted on the reed center 5, and the front end 4a is normally lifted off the reed front 8 by the load of an action mechanism 7, which will be described later. The rear end portion 4b is placed on the rear reed 9 via the felt 10. Like a general piano, the keyboard reed 2 is formed in a lattice shape by the above-mentioned middle 5, front 8, and back 9, and a plurality of keyboard joists 11 that integrally connect these three members. has been done. In addition,
An oval key pin 12 is installed on the front part 8 of the key 4, and the upper end of the oval key pin 12 is always engaged in a recess (not shown) formed on the lower surface of the front end of the key 4.
Movement of the key 4 in the left and right direction is restricted and prevented.

A frame 13 made of cast iron or the like is disposed almost vertically behind the shelf board 1, and the strings 3 are secured to the top and bottom ends of the frame 13 by pins. It is stretched.

The action mechanism 7 is disposed above the rear end of the key 4, and includes a wippen 14 that is rotationally driven by the key 4. This uipen 14
One end of the key 4 is rotatably supported on the center rail 15 via a wippen flange 16, and a wippen heel 14A is integrally fixed to the lower surface of the free end side.
It is normally placed on a capstan 17 planted on the upper surface of the rear end. In addition, a jack flange 19 is provided on the upper surface of the approximately central portion of the wippen 14.
A substantially L-shaped jack 18 is provided, the lower end of which is rotatably supported via a jack spring 20, and which is always given a counterclockwise rotational tendency in the drawings. The wippen 14 is pushed up by the capstan 17 which rises as the key 4 is driven, and the jack 18 moves the movement of the wippen 14 to the center rail 1.
The power is transmitted to a butt 22 which is rotatably supported on the shoulder portion of the arm 5 via a butt flange 21. Therefore, the butt 22 rotates counterclockwise, and the hammer 23 disposed on the butt 22 rotates counterclockwise.
hits string 3. The jack 18 is rotated clockwise against the jack spring 20 as the small jack 18A comes into contact with the regulation retching button 24 and its upward movement is blocked during its ascent. The jack 1
The upper end of 8 is temporarily escaped from the lower part of butt 22. After the string-striking operation, this jack 18 rotates and returns in conjunction with the lowering of the wippen 14 as the key 4 returns, so that its upper end enters the lower part of the butt 22 again, enabling the next string-striking operation. Make it.

A back check wire 25 and a bridle wire 2 are further provided on the upper surface of the free end side of the wippen 14.
6 are installed at an angle to the right in the figure, that is, toward the front end of the key 4, and at the upper end of the back checker wire 25 there is a string that bounces back after the string is struck by the reaction and the force of the butt spring 28. Back check 27 to catch the coming bat 22
is fixed. On the other hand, a catch 29 is fixed to the butt 22 via a catch shank 30, and is configured to collide with the buck check 27 and be elastically received when the butt 22 returns to rotation. The bridle wire 26 and catcher 29 are connected by a bridle tape 31, and this connection causes the return of rotation of the butt 22, in other words the hammer 23, to follow the return of rotation of the wippen 14.
This prevents the string 3 from being struck twice after the string is struck, and also speeds up the return of the hammer 23 to its initial position. Note that the hammer 23 comes into contact with the hammer rail 32 and is locked at the initial position.

A damper mechanism 33 is further disposed on the center rail 15. This damper mechanism 33
The damper lever 36 has an intermediate portion rotatably supported on a damper lever flange 34 fixed to the upper surface of the center rail 15, and is always given a counterclockwise rotational habit by a damper lever spring 35. The damper 38 is fixed to the upper end of the damper lever 36 via a damper wire 37, and the damper 38 is normally pressed against the string 3 by the force of the damper lever spring 35. This prevents the string 3 from vibrating freely. When the key 4 is driven, as the wippen 14 rotates upward, the damper spoon 39 installed on the upper surface of the wippen 14 on the rotational fulcrum side comes into contact with the lower end of the damper lever 36, causing the damper lever to move. By pressing and rotating against the spring 35, the damper 38 is separated from the string 3, and the string 3 after the damper 38 is struck by the hammer 23.

A key drive device 40 is disposed on the rear end surface of the shelf board 1, that is, the surface facing the frame 13. This key drive device 40 has a solenoid 42 whose lower end is rotatably supported by a solenoid mounting member 41 attached to the rear end surface of the shelf board 1, and a plunger is provided in a hole provided at the center of the solenoid 42. The lower end of 43 is inserted so as to be vertically movable with a slight gap maintained. The solenoid mounting member 4
1 further has a lower end portion of a lever mounting member 44 fixed integrally or separately, an intermediate portion is rotatably supported at the upper end of the lever mounting member 44, and one end is rotatably supported at the upper end of the plunger 43. A rotary lever 45 is provided which is movably connected and whose other end abuts and engages the lower surface of the capstan 17. In this case, the engagement between the capstan 17 and the rotating lever 45 is achieved by inserting a cushioning member 47, such as rubber, into a U-shaped groove 46 formed at the other end of the rotating lever 45, as shown in FIG.
This is done by adhering the post wire 48 and inserting the post wire 48 therethrough, and bending the other end in the vertical direction to abut the lower surface of the capstan 17.

In such a configuration, when the solenoid 42 is excited by applying a voltage pulse and the plunger 43 is momentarily pulled down, the rotating lever 45 rotates counterclockwise and pushes up the capstan 17, so that the key 4 appears as if it were It operates as if a key was pressed by hand to drive the action mechanism 7.

Thus, the key drive device 40 with such a configuration
According to the above, the solenoid 42 is disposed on the rear end surface of the shelf board 1 by utilizing the space provided between the rear end of the shelf board 1 and the frame 13, so that the space between the shelf board 1 and the keyboard reed is There is no need to form a through hole for the plunger in 11, so the strength of the shelf board 1 and the keyboard reed 11 is not impaired, and the key drive device 4
0 can be easily made into a unit, its installation,
Position adjustment work is also easy.

FIG. 3 is a side view of main parts showing another embodiment of this invention. In this embodiment, a rotating lever 45 is pivotally supported by a flange 50, and the tip of the rotating lever 45 is inserted between the rear end 4b of the key 4 and the rear reed 9, and is attached to the lower surface of the rear end 4b. This is what they were brought into contact with. It will be obvious that the key 4 can be operated in this configuration as well in the same manner as in the above embodiment.

It should be noted that although the above embodiments have all been described with reference to the case where the invention is applied to an upright type automatic performance piano, the present invention is of course not limited to this and can also be applied to a grand type.

As explained above, the key drive device for a player piano according to this invention has a solenoid arranged vertically on the rear end surface of the shelf board, and converts the descending motion of the plunger into an ascending motion using a rotary lever. Since the driving force is configured to be transmitted to the key, the loss due to the weight load on the plunger is extremely small, and a large driving force can be obtained compared to a plunger of the same size. In addition, the installation and adjustment of the plunger is easy, and there is no need to modify the shelf board or keyboard reed. Therefore, the strength of the shelf board, etc. is maintained well, and when used on a grand type piano, it is easy to insert and remove the keyboard reed. The practical effects are very large.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of the action mechanism of an embodiment of an upright automatic performance piano equipped with a key drive device according to this invention, Fig. 2 is a plan view of the main part of the device, and Fig. 3 is a plan view of the main part of the device. FIG. 7 is an enlarged side view of main parts showing another embodiment of the invention. 1... Shelf board, 4... Key, 7... Action mechanism, 13... Frame, 40... Key drive device, 4
1... Solenoid mounting member, 42... Solenoid, 43... Plunger, 45... Rotating lever.

Claims (1)

[Scope of utility model registration request] a key disposed on the shelf so as to be swingable in the vertical direction and driving an action mechanism; a mounting member provided on the rear end surface of the shelf; and a key disposed vertically via the mounting member; a solenoid that drives the plunger by being excited by an electric signal; an intermediate portion is rotatably supported by the mounting member; one end is connected to the plunger; the other end is engaged with the key; A key drive device for a self-playing piano, comprising a rotary lever that converts a downward movement of a plunger into an upward movement and transmits the same to the key.