JPH01217398A - Key driving device for musical instrument with keyboard - Google Patents

Abstract

PURPOSE:To realize smooth key depressing operations by fitting iron cores to keys through automatic core adjusting mechanisms provided on the back of the keys and allowing the relative movement between the keys and iron cores, and inclinations of the iron cores against the keys by means of the mechanisms. CONSTITUTION:An iron core 19 is fitted to a key 1 through an automatic core adjusting mechanisms 37 provided on the back of the key 1 and a degree of freedom is given to the fitting position of the iron core 19, namely, provided position of an electromagnetic actuator 20 without giving any influences to the appearance of the key 1. The iron core 19 fitted to the key 1 is allowed to move in a plane which is almost perpendicular to the key depressing direction and to incline against the key 1 by means of the mechanism 37. Therefore, even if a little error is produced in the front-back and right-left directions when the iron core 19 is fitted to the key 1 or due to an environment change after fitting, the error is automatically corrected and the core 19 is adjusted to the state where the axial center is aligned to the solenoid 17 of the actuator 20. Accordingly, smooth key depressing operations can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION By attaching the iron core of an electromagnetic actuator that performs a key pressing operation so that it can move and swing relative to the key, the present invention provides a key driving device that can be attached to an existing keyboard instrument without requiring major modification. It is designed so that it can be easily installed.

[Prior Art] Conventionally, a self-playing piano has been known in which an electromagnetic actuator operates the keys of the piano to perform key depression operations to achieve automatic performance.

As a self-playing piano of this kind, the
The automatic playing piano shown in FIG. 8, for example, has a plurality of keys 1, and a hammer 3 and a damper based on the movement of the keys 1. A controller 13 is built into the main body of the piano, which has an action mechanism 7 that drives each of the hammers 5 and a string 9 that is struck by the hammer 3. , and a solenoid 17 that applies one inch of force to the key 1.

A player piano having such a configuration functions as a recording mode and a playback mode, and when in the recording mode, a plurality of sensors 15 arranged on the trajectory of the hammer 3 detect the movement of the hammer 3 when the player strikes a string with a key operation. The string-striking force of the hammer 3 was estimated by calculating the speed i of the hammer 3 based on the detection result.

Once the string-striking force of the hammer 3 is estimated in this way, this string-striking force is stored in the storage section of the controller 13 along with key information that specifies the operated key 1 as string-striking information, and is stored until the end of the performance. The above operation is repeated.

Next, when the player piano is set to playback mode, the controller 13 specifies the key 1 to be driven based on the key information, and excites the lunoid 17 provided corresponding to the key 1 to drive the key 1. Attach the iron core 19 to 1 by suction,
A predetermined attraction force (key pressing force) is applied to the key 1. At this time 1, the force applied to the key 1 from the solenoid 17 is of a magnitude that causes the hammer 3 to generate a string-striking force of the magnitude represented by the string-striking information, so the hammer 3 is in the same state as in the recording mode. A string-striking force is generated, and the continuous movement of the hammer 3 reproduces the same performance as in the recording mode.

Here, there is a problem that if there is even a slight error in the mounting position between the solenoid 17 and the iron core 19 that constitute the electromagnetic actuator 20, the movement of the key 1 will be hindered due to friction between the two. When fixing the iron core 19 to the key 1, extremely high precision is required. In response to these demands, in order to provide an automatic performance function from the beginning, the trajectory of the iron core 19, which is determined from the position and size of the key 1, was made to match the axis of the solenoid 17 during the manufacturing stage of the piano. If arranged, it is possible to configure a player piano so that not even the slightest error occurs for all the keys.

However, it is difficult to completely eliminate these errors even at the piano manufacturing stage. Furthermore, even if it were possible to eliminate this error, since the keys are made of wood, for example, the keys may warp or bend due to aging or changes in humidity. The heat generated by the actuator coil causes the yoke to fall off the keyboard, causing misalignment with the keyboard, making it difficult to play.

Furthermore, if a key drive device for automatic performance is to be retrofitted to an existing piano, the iron core 19 must be installed and fixed in alignment with the axis of the solenoid 17 for all keys. There was a problem in that not only was it extremely difficult to maintain the mounting accuracy, but the modification became extensive and the cost increased.

A structure as shown in Fig. 9 (see Japanese Utility Model Application Publication No. 5゜8-38194 ) has been known for a long time.

In this player piano, a shaft 23 is loosely inserted into a through hole 21 provided in a key 1, and its head 23a is locked to the key 1, and an iron core 19 is attracted to the shaft 23 by a solenoid 17.
is attached.

Therefore, according to this structure, the iron core 19 is connected to the solenoid 17.
Since the lateral position and inclination of the iron core 19 can be freely changed, errors in the mounting positions of the iron core 19 and the solenoid 17 can be absorbed, and the requirement to maintain the mounting accuracy of the iron core 19 can be satisfied.

[Problems to be Solved by the Invention] However, even with the conventional player piano shown in FIG. There are new issues with functionality, such as:

Drilling the through hole 21 in the key 1 would spoil the appearance and damage the product value, so it is unavoidable to open the through hole 21 in the vicinity of the balance bin 25 located inside the piano. The electromagnetic actuator 20 is required to generate an extremely large attraction force because a force must be applied from the vicinity of the balance pin 25, which serves as a fulcrum, to cause the key press operation. For this reason, the amount of heat generated from the solenoid 17 increases, and the solenoid 17 also becomes large, and it has to be arranged for each key 1, making it difficult to layout the large number of electromagnetic actuators 20. was there.

Also, due to the structure of the keyboard on the pull side, the balance bin performer f!
1.11 There is no regularity in the horizontal pitch of each steel amount between the vicinity (front side) and the action side, and this pitch also varies depending on the manufacturer and the size of the piano. The problem was that it was impossible to create a yoke that could be shared.

Therefore, especially when installing a key drive device that achieves automatic performance on an existing piano, the size of the electromagnetic actuator and the arrangement method should be determined individually after checking the keyboard's splitting structure, etc. However, there was a problem in that converting existing pianos to automatic performance required a large amount of money and extensive work.

The present invention has been made in view of the above-mentioned conventional circumstances, and is a key for a keyboard instrument that can be easily retrofitted to an existing keyboard instrument and can achieve automatic performance of the keyboard instrument. The purpose is to provide a driving device.

[Means for Solving the Problems] The key driving device for a keyboard instrument of the present invention includes a solenoid provided on a shelf board, and an iron core provided on the key and constituting an electromagnetic actuator together with the solenoid. In a key drive device for a keyboard instrument, in which the iron core is attracted toward the shelf board by energizing a solenoid and a key is pressed, the iron core is attached to the key via an automatic alignment mechanism installed on the back of the key. installation,
The present invention is characterized in that the iron core is provided around the key while allowing relative movement between the key and the iron core and the inclination of the iron core with respect to the key within a plane substantially perpendicular to the key depression direction by an automatic centering mechanism.

[Function] In the key drive device for a keyboard instrument of the present invention, the iron core is attached to the key via the self-aligning mechanism provided on the back side of the key, and the iron core can be attached to the key from here on without affecting the appearance of the key. Give flexibility in the mounting position, that is, the placement position of the electromagnetic actuator. The iron core, which is placed one inch into the key, is allowed to move in a plane approximately perpendicular to the key pressing direction and tilt with respect to the key due to the self-aligning mechanism, allowing for slight longitudinal and horizontal errors during installation. Even if the electromagnetic actuator's solenoid and shaft center are aligned, this is automatically corrected even if the environment changes after installation.

[Example] The key drive device for a keyboard instrument of the present invention will be specifically described based on an example. Incidentally, the same parts as those in the conventional example described above are denoted by the same reference numerals (overlapping explanations will be omitted).

As shown in FIGS. 1 to 3, an electromagnetic actuator 20 according to an embodiment of the present invention is provided between a front reed 31 and a liquid 33, and presses a key by applying an attractive force to the key 1. Compared to the conventional structure shown in FIG. 9, this arrangement position is on the front 31 side of the reed, that is, on the back side of the key pressing part of the key 1. The solenoid 17 of the electromagnetic actuator 20 is fixed on a shelf board 35, and the iron core 19 of the electromagnetic actuator 20 is attached to the back surface of the key 1 via a bracket 37 forming a self-aligning mechanism.

A small-diameter shaft portion 19a is provided protruding from the upper end of the iron core 19, and a large-diameter head portion 19b is further provided at the upper end of the shaft portion 19a.As a result, the iron core 19 has an overall shape similar to that of the shaft portion 19a.
It has a shape with a constricted part at.

The bracket 37 is attached to the back surface of the key 1 with a screw 39, and its tip 37a is bent and formed to be parallel to the back surface of the key 1 and spaced apart from it at a distance larger than the thickness of the head 19b of the iron core. A rectangular hole 41 is formed in the tip end 37a of the bracket.
The shaft portion 19a of the iron core is of such a size that it cannot be inserted loosely or straightly in the vertical direction when the head 19b is located at the center. The size of the hole 41 is such that it can be moved by a predetermined amount with respect to horizontal displacement, and is allowed to be tilted up to a predetermined angle.

A notch 43 is formed from the tip of the bracket 37 to the hole 41, and the width of this notch 430 is such that the shaft portion 19a of the iron core can pass therethrough.

From the above structure, the iron core 19 has a notch 43 in the shaft portion 19a.
is attached to the key 1 via the bracket 37 by passing through the hole 41 and positioning the head 19b on the edge of the hole 41. Therefore, the shaft portion 19a can move laterally within the hole 41, and the head portion 19a can move laterally within the hole 41.
Since b can swing within the gap between the back of the key 1 and the bracket 37 without any downward play, the iron core 1
Movement in a plane approximately perpendicular to the key pressing direction of 9 and key 1
A tilt with respect to is allowed. That is, even if the core 19 attached to the key 1 via the bracket 37 is axially misaligned with the solenoid 17 fixed to the shelf board 35, Then, the iron core 19 moves back and forth, left and right, or the inclination of the iron core 19 is changed, so that the axes of the iron core 19 and the solenoid 17 automatically align.

Here, in this embodiment, since the hole 41 is rectangular, the range of movement of the iron core 19 in the front, back, left, and right directions can be widened, compared to, for example, a circular hole.

In addition, between the back surface of the key 1 and the top surface of the iron core head 19b and the hole 4
Cushion materials 45, 46 are interposed between the upper surface of the edge of the iron core 19 and the lower surface of the core head I9b, and these cushions 45, 46 bend themselves to allow the iron core 19 to tilt. 19, the key 1, and the bracket 37, the generation of noise is prevented.

In this embodiment, the cushion material 45 is
While the cushion material 46 is pre-attached to the b side,
is pre-attached to the bracket 37 side, and by subassembling the parts, the work when attaching the key drive device to the rear elbow with respect to the existing beer chisel is facilitated.

After locking the core 19 to the bracket 37, screw the screw 47 into the back of the key 1 through the spacer 47a to position it within the notch 43, and remove the core shaft 19a from the notch 43. Since the lock and the bracket 37a are securely fixed to the key 1, and the iron core 19 is attached to the back of the key via the bracket 37 as described above, the iron core, that is, the electromagnetic actuator 20 can be fixed without damaging the appearance of the keyboard. It can be arranged at a position away from the balance pin 25 between the front of the reed 31 and the liquid submersion 33.

Therefore, as shown in FIG. 5, the electromagnetic actuators 20 can be disposed in the parts that are regularly arranged in every octave between the keys regardless of the structure of the keyboard on the pull side, so that they can be used in common for all pianos. By creating a yoke, it is possible to retrofit the key drive device at low cost and with easy work.

The electromagnetic actuators 20 provided for each key 1 are arranged in a staggered manner, thereby avoiding mutual interference and increasing the diameter of the solenoid as much as possible.

Depending on the player piano equipped with the key drive device as described above,
When the solenoid 17 is excited and the iron core 19 is attracted,
Key 1 engaged with iron core head 19b via bracket 37
is pulled down to perform a key press operation.

FIG. 6 is a drawing according to another embodiment of the present invention.

In this embodiment, the self-aligning mechanism is constructed from a ball joint. That is, a shaft 53 is swingably connected to the upper end of the iron core 19 via a ball joint 51.
This shaft 53 is swingably connected to a bracket 55 provided on the back surface of the key 1 via a ball joint 57, thereby allowing movement in a plane substantially perpendicular to the key pressing direction.
The iron core 19 is provided in the key 1 while allowing the inclination with respect to the lock.

Even in this embodiment, since the key press operation is performed by the pull-down operation due to the suction force of the solenoid 17, the key press operation force can be transmitted without any problem even through the hole joint.

FIG. 7 is a drawing according to still another embodiment of the present invention.

In this embodiment, the self-aligning mechanism is composed of a string 61 and a spring 63 that assists the string.

That is, a bracket 65 provided on the back side of the key and the upper end of the iron core 19 are swingably connected via a string 61, and a spring 63 is interposed between the bracket 65 and the upper end of the iron core 19 to connect the iron core. 19 is held in a constant position without vertical play, thereby allowing movement in a plane substantially perpendicular to the key pressing direction and tilting with respect to the key I, while allowing the iron core to be attached to the key I. There are 19.

Even in this embodiment, since the key press operation is performed by the pulling down operation by the suction force of the solenoid 17, the key press operation force can be transmitted even by the flexible string 61 without any problem.

[Effect] According to the key drive device for a keyboard instrument of the present invention, an iron core is attached to the key via an automatic alignment mechanism provided on the back side of the key, and this automatic alignment mechanism controls the relative movement between the key and the iron core and the key. By allowing the iron core to tilt relative to the angle of view, the positional relationship between the iron core and the solenoid of the electromagnetic actuator is maintained in a normal state, preventing abnormal friction between the two and achieving smooth key press operation. can do. The position of the iron core, that is, the electromagnetic actuator, can be set relatively freely, so the electromagnetic actuator can be placed at a substantially constant position regardless of the piano manufacturer or piano model. Cost reduction is achieved by sharing electromagnetic actuators, and an existing piano can be easily converted into a self-playing piano.

[Brief explanation of the drawing]

FIG. 1 is a side view showing one embodiment of the present invention, and FIG. 2 is a side view showing one embodiment of the present invention.
3 is an exploded perspective view of the self-aligning mechanism, FIGS. 4(a) and 4(b) are explanatory diagrams of the function of the self-aligning mechanism, and FIG. 5 is an exploded perspective view of the self-aligning mechanism. A plan view of the keyboard showing the arrangement of the electromagnetic actuators, FIG. 6 is a side view showing one embodiment of the pond of the present invention, FIG. 7 is a side view showing yet another embodiment of the present invention, and FIG. Side view of conventional example FIG. 9 is a side view of a conventional example of a pond. 1... Key, ]7... Solenoid, 19... Iron core, 20... Electromagnetic actuator, 35... Shelf board, 37... Bracket, 41... Hole, 51.57... Hole join), 61... String, 63... Spring. Patent applicant Kiyoshi Kuwai, agent for Yamaha Corporation, patent attorney - Figure 2 Self-aligning M& Action explanatory diagram Figure 5 Plan view of the plow board

Claims (1)

[Claims] A keyboard that has a solenoid provided on a shelf board and an iron core that is provided on a key and constitutes an electromagnetic actuator together with the solenoid, and when the solenoid is energized, the iron core is attracted toward the shelf board and a key press operation is performed. In a musical instrument key drive device, the iron core is attached to the key via an automatic alignment mechanism provided on the back of the key, and the automatic alignment mechanism allows the relative movement of the key and the iron core in a plane approximately perpendicular to the direction in which the key is pressed. A key drive device for a keyboard instrument, characterized in that an iron core is provided in the key while allowing the inclination of the iron core with respect to the key.