JPH0521114Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a self-playing piano, more specifically, a self-playing piano in which an actuator is driven by reproducing a pre-stored electric signal and keys are driven based on the signal. This invention relates to improvements in key drive devices.

(Prior Art) As a conventional key drive device for this type of player piano, for example, the one shown in Fig.
55-113584) is known.

In this device, a solenoid 9 is arranged in a player piano 1 at a position below and further back from a fulcrum 5 for the swing of each key 3, that is, directly below a key action mechanism 7. The solenoid 9 drives the key 3 and is attached to the mounting plate 11.

That is, when each solenoid 9 is excited by the drive signal, the plunger 13 pushes up the back part of the key 3 from below. As a result, the key 3 swings around the fulcrum 5 in the clockwise direction in the figure, thereby operating the key action mechanism 7.

(Problem to be solved by the invention) However, in the case of such a conventional key drive device for a player piano, the solenoid for driving the key was disposed further back than the fulcrum of the key.
Since different types of pianos have different configurations (structure, dimensions, etc.) of their key action mechanisms, solenoid units for driving the keys with different configurations had to be manufactured and installed separately. That is, a problem has arisen in that the solenoid unit for driving the keys cannot be shared by different types of pianos.

(Means for solving the problem) Therefore, the present invention provides a keyboard reed 25 and a shelf board 23.
A player piano includes a plurality of keys 21 and a plurality of key drive units 33, and the keyboard reed 25 has a front reed 31 and a middle reed 27,
The plurality of keys 21 are supported so as to be able to swing around the middle of the reed 27, and the plurality of key drive units 33 are arranged between the front of the reed 31 and the middle of the reed 27 corresponding to each key 21. The key drive unit 33 is arranged in a space defined below each key 21 and above the shelf board 23 to swing each key 21. The actuator 50 includes a plunger 55 and a solenoid coil 57. The plunger 55 is provided to be movable up and down with respect to the shelf board 23, and the solenoid coil 57
aims to solve the above problems by providing a self-playing piano that is wrapped around a plunger 55.

(Operations and Effects) In the automatic performance piano according to the present invention, each key 21 is supported so as to be swingable about the reed center 27 of the keyboard reed 25 as a fulcrum. However, these keys 21
A key drive unit 33 for driving the keys 21 is disposed below the keys 21 and between the middle 27 of the reed and the front 31 of the reed.

As a result, the space between the reed middle 27 and the reed front 31 has almost the same structure even when the pianos are of different types (for example, an upright piano and a grand piano with different string-striking mechanisms), so the keys are The drive units 33 may have the same configuration, ie, size, etc. Even for different types of pianos, the key drive unit 33 as a whole can be used in common. That is, the key drive unit 33 and, in turn, the actuator 5
It is now possible to share 0. Therefore, the automatic performance piano according to the present invention has wider versatility than conventional pianos.

(Example) Hereinafter, an example of a key drive device for a player piano according to the present invention will be described with reference to the drawings.

1 to 3 show an embodiment of the present invention.

In FIG. 1, 21 is a key, and a balance key pin 29 is attached to the middle 27 of the keyboard reed 25 on the shelf board 23.
It is supported so as to be able to swing vertically using this as a fulcrum. Keyboard reto 25, rekomae 31 and rekochu 2
7, below the key 21 and above the shelf board 23,
A predetermined flat space is defined, and a key drive unit 33 is arranged within this space.
A sensor unit 35 is also installed in this space in front of the key drive unit 33. Incidentally, both of these units 33 and 35 may be arranged and attached to an integrated key frame.

Incidentally, in FIG. 1, an I/O board 39 is fixed on the shelf board 23 between the middle 27 of the reed and the rear 37 of the reed. In addition, in the same figure, the rear end of the key 21 is supported on the upper surface of the rear reed 37 via a felt 41,
A capstan screw 43 is provided on the upper surface of the rear end of the key 21 and projects upwardly. This capstan screw 43 constitutes a part of a key action mechanism (not shown). Also, Yokoshimae 31
An oval key pin 45 is embedded in the key 21, and the front end of the key 21 is guided by the oval key pin 45.

Here, as shown in detail in FIG. 2, the key drive unit 33 has a plurality of electromagnetic actuators 50 provided corresponding to each key 21. That is, the unit 33 includes a yoke 51 which is bent into a U-shape, a plunger 55 which is held vertically movably in a holder 53 between an upper yoke 51A and a lower yoke 51B of this yoke 51, and a plunger 55. (See FIG. 3), and a solenoid coil 57 wound around the outer surface of the holder (bobbin) 53 between the upper and lower yokes 51A and 51B. Note that cushion members 61 and 63 made of felt are attached to both the upper and lower surfaces of the plunger 55, and exert a shock-reducing and noise-muffling effect. In addition, the yoke 51 is attached to the fixing base 65 by screws 67.
The screw hole 69 of the lower yoke 51B is formed as an elongated hole, so that the position of the lower yoke 51B can be adjusted in the extending direction of the key 21 (front-back direction).

Furthermore, these plungers 55 (electromagnetic actuators 50) are arranged below each key 21, and are arranged in a staggered manner, alternating back and forth with respect to the yoke 51 (for effective use of space). ). Each plunger head 5
5A protrudes from the hole 71 of the upper yoke 51A, and each abuts one end of a lever 73 provided to be swingable in a vertical plane. The lever 73 is formed of a thin leaf spring, and is supported by a flange 75 (fulcrum) at its longitudinally intermediate portion so as to be movable up and down, and the other end (front end) 73A is formed in a fork shape. Note that the flange 75 is screwed to the front end surface of the upper yoke 51A.

A fork 73A at the other end of the lever 73 engages with a horizontal piece 77A of a hook 77 that projects downward from the lower surface of the key 21. That is,
When the lever 73 swings and the fork 73A descends, the hook 7 engages with the fork 73A.
7, the key 21 is pulled down (depressed). Note that a sound-insulating cushion is attached to the fork 73A, and the thickness of this cushion can be changed by appropriately interposing a spacer or the like to finely adjust the vertical position.

Further, a plate-shaped shutter 79 protruding downward from the horizontal piece 77A of the hook 77 constitutes a part of the sensor unit 35. That is,
The shutter 79 is disposed so as to move up and down within a slit 83 formed in the main body 81 of the sensor unit 35 and extending along the vertical direction, and one or more pairs of photocouplers 85 (light emitting) are provided on both sides of the slit 83. element and light receiving element) are respectively arranged. The sensor unit 35 detects whether or not a key is pressed and the speed at which the key is pressed.

Further, the stroke, which is the amount of protrusion of the plunger 55, differs between the rear side and the front side, and is about 2 mm and about 3 mm, and the vertical stroke of the key drive part (hook part 77) is different. Approximately 7mm~8mm
It is said that Note that the hook portion 77 is arranged substantially in a straight line in the direction in which the keys 21 are arranged. Further, the hook 77 and the fork 73A are engaged by shifting the entire key drive unit 33 on the fixing base 65 in the front-rear direction.

In the key drive device for a player piano having the above configuration, the key drive unit 33 is connected to the key 21.
Because it is placed between the reed center 27 and the reed front 31, which are the fulcrum of the reed, and also on the shelf board 23, it is convenient for playing regardless of the upright or grand type, and even if the overall size of the piano is different. Therefore, since the distance between the middle 27 of the reed and the front 31 of the reed is constant for almost all pianos, the key drive unit 3
The size of 3 can also be made constant. That is, it is possible to share the unit 33, the electromagnetic actuator 50, etc.

Furthermore, in this embodiment, the electromagnetic actuator 50
Since the key 21 is driven via the lever 73 instead of being driven directly by the plunger 55, manufacturing errors, assembly errors, etc. can be easily absorbed by fine adjustment. can. For example, the dimensional error in the longitudinal direction of the key 21 and the installation error in the same direction can be adjusted when the screw 67 is fastened to the elongated hole 69. Further, errors in the vertical direction can be absorbed by changing the thickness of the cushion 73A.

Furthermore, by using the lever 73, the plunger 55
It goes without saying that a boosting effect on the output may also occur. Therefore, it is also possible to employ an inexpensive electromagnetic actuator 50 in which the number of turns of the solenoid coil 57 is reduced.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the key drive device for a player piano according to the present invention, FIG. 2 is a schematic exploded perspective view showing the main parts of the key drive device according to the embodiment, and FIG. FIG. 4 is a cross-sectional view showing a mounting portion of an actuator according to one embodiment, and FIG. 4 is a schematic vertical cross-sectional view showing a conventional key drive device for a player piano. 21...key, 25...keyboard reed, 27...reed middle,
31... Before the reed, 35... Sensor unit, 50...
...Electromagnetic actuator.

Claims (1)

[Scope of claims for utility model registration] (1) Keyboard reed 25, shelf board 23, and multiple keys 21
and a plurality of key drive units 33, the keyboard reed 25 has a front reed 31 and a middle reed 27, and the plurality of keys 21 have the middle reed 27 as a fulcrum. The plurality of key drive units 33 are supported so as to be able to swing freely, and each key drive unit 33 is
1, each of the keys 21 is disposed in a space defined between the front of the reed 31 and the middle of the reed 27, below each key 21 and above the shelf board 23. The key drive unit 33 has an actuator 50, the actuator 50 has a plunger 55,
A solenoid coil 57, the plunger 55 is provided to be movable up and down with respect to the shelf board 23, and the solenoid coil 57 is wound around the plunger 55. playing piano. (2) Information accompanying the key press operation of each key 21 is
A plurality of sensors 3 respectively provided corresponding to
5. The self-playing piano according to claim 1 of the utility model registration claim detected by 5.